JP3543775B2 - Transmission device, reception device, transmission system using them, transmission method and reception method, and transmission method using these - Google Patents

Description

【０２９０】
ここで、信号の形態はカラーバーを使用し、送信装置側で付加するジッタは周波数１ＭＨｚ〜６ＭＨｚであり、ジッタ量は０．７ｎｓ以下であり、信号振幅は９０％又は１００％のものを使用した。すなわち、ジッタは図２８に示す範囲内のジッタを採用して行った。図２８はＳＭＰＴＥ２５９Ｍで規定されている伝送条件の一部を示している。
【０２９１】
ここで、ジッタとはデジタル信号の伝送の理想的な位置（タイミング）に対する時間変動であり、タイミングジッタとはある特定の周波数（一般的には１０Ｈｚあるいはそれ以下）より大きな周波数で起きるデジタル信号の伝送の位置（タイミング）的変動をいう。また、アライメントジッタとはデジタル信号の伝送の信号から抽出（再生）されたクロックに対する位置（タイミング）的な変動をいい、ユニットインターバル（Ｕｎｉｔ Ｉｎｔｅｒｖａｌ：以下ＵＩという。）とは１クロックサイクル時間をいい、シリアル信号の伝送間の名目上の最短時間に相当する。これら発明者が本実験で使用した有線の伝送路上に伝送する信号の伝送方法はＳＭＰＴＥ２５９Ｍ規格あるいはＳＭＰＴＥ２９２Ｍ規格で規定されているものの範囲内である。
【０２９２】
誤り測定器でフィールド単位における誤り検出を行い誤り数をカウントアップした。また、測定時間と誤り数からエラーレートと誤り発生間隔を算出した。なお、フィールド単位の誤り検出を行っているので、フィールド単位での誤り数が１ビット以上であっても測定結果として１フィールドに１回の誤りがあったものとしている。従って、実際のエラーレートはデスクランブルによる誤り波及や１フィールド内で複数個の誤りが発生することも考えられることから、以下に示すエラーレートの測定結果よりも、さらに悪くなる可能性がある。
【０２９３】
上記条件に沿って発明者が実験を行った結果を（表２）〜（表７）に示す。
【０２９４】
【表２】

【０２９５】
【表３】

【０２９６】
【表４】

【０２９７】
【表５】

【０２９８】
【表６】

【０２９９】
【表７】

【０３００】
ここで、エラーレートは
エラーレート＝誤り数／（測定時間×２７０Ｍｂｐｓ）
で計算している。
【０３０１】
以上のような条件であっても、厳しい伝送環境では誤り率が１×１０^-8程度になる場合がある。この誤り率は従来の非圧縮のデジタル映像信号を伝送する場合は、肉眼でほとんど検出できないため、実用上問題なかった。
【０３０２】
しかし、ＭＰＥＧ（Ｍｏｖｉｎｇ Ｐｉｃｔｕｒｅ Ｅｘｐｅｒｔｓ Ｇｒｏｕｐ）やＤＶＣ（Ｄｅｇｉｔａｌ Ｖｉｄｅｏ Ｃａｓｓｅｔｔｅ）のような圧縮信号を伝送する場合、図５に示すように１ビットのエラーがＤＣＴのエリア単位、スライス単位、あるいはＧＯＰ（Ｇｒｏｕｐ ｏｆ Ｐｉｃｔｕｒｅ）単位で誤り波及を引き起こし、大きな画質劣化になる。画質劣化の影響度合いは、圧縮アルゴリズムやビット誤りの発生した場所により異なるが、いずれにしても何らかの誤り対策を講じなければ実用上問題となる。
【０３０３】
例えば、伝送速度２７Ｍｂｐｓ（ｂｉｔ ｐｅｒ ｓｅｃｏｎｄ）の圧縮信号をクロック周波数２７０ＭＨｚの条件で伝送する場合、ビット誤り率が「１×１０^-11」で平均誤り発生間隔は約１時間、ビット誤り率が「１×１０^-10」で平均誤り発生間隔は約６分、ビット誤り率が「１×１０^-9」で平均誤り発生間隔は約３７秒、ビット誤り率が「１×１０^-8」で平均誤り発生間隔は約３．７秒となるので、伝送パラメータが以上のような条件であっても実用に耐えることができない。
【０３０４】
ここで、誤り対策の手段として、誤りのあったパケットを再送するという方法があるが、これでは再送による伝送時間が遅延するとともに片方向伝送システム（例えば、ＳＭＰＴＥ ２５９Ｍ）では再送メカニズムを実現するのが困難である。
【０３０５】
一方、誤り訂正符号を付加する方法では、伝送する信号に含まれる情報信号の割合が減少するため伝送効率が低下する。付加情報を少なくするために誤り訂正符号の符号長を短くすれば、誤り訂正能力は低くなる。従って、どの程度の符号長の誤り訂正符号を付加すれば、伝送効率をあまり減少させることなく十分な誤り訂正能力を保つことができるかが課題となっている。
【０３０６】
本実施の形態は、かかる課題を解決するものであり、以下にどの程度の符号長の誤り訂正符号を付加すればよいかをその理由とともに詳細に説明する。
【０３０７】
図２９はリードソロモン符号の誤り訂正能力を示す図である。ここで、図２９の横軸に示すＢＥＲ（Ｂｉｔ Ｅｒｒｏｒ Ｒａｔｅ）はビットエラーレート、すなわち、伝送路上でのビット誤りの発生率を表しており、図９の縦軸に示すＰｂｅ（Ｂｌｏｃｋ ｅｒｒｏｒ ｒａｔｅ）はブロックエラーレート、すなわち、誤り訂正を行っても訂正できなかったブロックの発生率を表している。
【０３０８】
図２９においてブロック長Ｎ＝２５５バイト（１バイト＝８ビット）であり、８ビットのリードソロモン符号を付加する場合の最大のブロック長である。また、図２９はスクランブルドＮＲＺＩ符号による誤り波及をも考慮した図である。すなわち、この方式は伝送路上でデジタル信号の１と０が平均的に発生するようにランダマイズを行うものである。この方式では誤りが発生すると次に続く１１ビットの内６ビットに誤りが伝播する。従って、１ビットのエラーが発生すると必ず２ワード（１ワード＝１０ビットである）にわたって誤りが波及する。従って、リードソロモン符号の誤り訂正能力は、Ｔ＝２以上（すなわち誤り訂正符号は、最小でも４バイト以上）でなければならない。
【０３０９】
なお、誤り訂正符号自身もブロックの中に含んでいる。誤り訂正符号を一定にした場合、ブロック長が長くなるほど訂正能力は低くなるから、図２９は、最も誤り訂正能力の低い場合の訂正能力を示したものということになる。
【０３１０】
ここで、Ｔは、１ブロック中訂正可能なシンボル（バイト）の数を表しており、例えば、４バイトのリードソロモン（誤り訂正）符号をブロックに付加した場合、１ブロック中に２シンボル（バイト）までのシンボル（バイト）エラーが訂正可能（Ｔ＝２）であり、２バイトのリードソロモン（誤り訂正）符号を付加した場合、１ブロック中に１シンボル（バイト）までのシンボル（バイト）エラーが訂正可能（Ｔ＝１）である。 また、Ｔ＝０は、誤り訂正符号が付加されていない場合を示している。
【０３１１】
つぎに、（表２）〜（表７）及び図９からどの程度の符号長の誤り訂正符号を付加すればよいかをその理由とともに詳細に説明する。
【０３１２】
（表２）〜（表７）に示した誤り率の測定結果から、伝送パラメータが以上のような条件（ＳＭＰＴＥ ２５９Ｍ規格内の条件）内であっても厳しい条件のもとでは、ビットエラーレートが１×１０^-8程度になる場合が存在する。従って、図２９を用い２ｎバイト（Ｔ＝ｎ）（ｎは１以上の自然数）のリードソロモン（誤り訂正）符号を付加した場合に十分な誤り訂正能力を保つことができるかを検討する。
【０３１３】
（１）２バイト（Ｔ＝１）のリードソロモン（誤り訂正）符号を付加した場合ビットエラーレートが１×１０^-8とすると２バイト（Ｔ＝１）のリードソロン符号を付加し、これを用いて誤り訂正を行うことによりブロックエラーレートが約１×１０^-9まで改善される。この値は、伝送速度２７Ｍｂｐｓの圧縮信号を伝送する場合を想定するとブロックの誤りが２６時間に１回に発生という誤り発生間隔に相当する。従って、２バイト（Ｔ＝１）のリードソロモン符号を用いて誤り訂正を行うことにより充分な誤り訂正を行うことは難しい。
【０３１４】
なお、本実施の形態ではスクランブルドＮＲＺＩ符号による誤り波及をも考慮しているため、上記したようにリードソロモン符号の誤り訂正能力は、Ｔ＝２以上（すなわち誤り訂正符号は、最小でも４バイト以上）でなければならず、２バイト（Ｔ＝１）のリードソロモン（誤り訂正）符号は本実施の形態では意味をなさない。
【０３１５】
（２）４バイト（Ｔ＝２）のリードソロモン（誤り訂正）符号を付加した場合ビットエラーレートが１×１０^-8とすると４バイト（Ｔ＝２）のリードソロモン符号を付加し、これを用いて誤り訂正を行うことによりブロックエラーレートが３×１０^-13まで改善される。この値は、伝送速度２７Ｍｂｐｓの圧縮信号を伝送する場合を想定するとブロックの誤りが約１０年に1回に発生という誤り発生間隔に相当する。従って、４バイト（Ｔ＝２）のリードソロモン符号を用いて誤り訂正を行うことにより充分な誤り訂正を行うことができる。
【０３１６】
上述したように、リードソロモン符号を誤り訂正符号とし、その長さを４ワード（Ｔ＝２）とすることにより、付加情報を少なくし、かつ十分な誤り訂正能力を得るという両方の条件を満たすことができる。
【０３１７】
なお、リードソロモン符号と情報信号の各バイト毎に付加されているパリティビットとを併用する場合、誤りの発生したシンボル（バイト）位置がわかる。これにより受信装置若しくは受信方法においてパリティビットにより誤り箇所を検出し、その後リードソロモン符号により誤り訂正を行うことで誤り訂正能力は以下のようになる。
【０３１８】
パリティエラーの検出で１ブロック中４箇所のエラーバイトが検出された場合は、その４バイトのエラーについて訂正可能であり、パリティエラー検出で１ブロック中３箇所のエラーバイトが検出された場合は、その３バイトのエラーについて訂正可能であり、パリティエラー検出で１ブロック中２箇所のエラーバイトが検出された場合は、その２バイトのエラーとその他の位置不明な１バイトについて誤り訂正可能であり、パリティエラー検出で１ブロック中１箇所のエラーバイトが検出された場合は、その１バイトのエラーとその他の位置不明な１バイトについて誤り訂正可能であり、パリティエラー検出で１ブロック中エラーバイトが検出されなかった場合は、１ブロック中位置不明な２バイトの誤り訂正可能である。
【０３１９】
以上、上記した構成により、リードソロモン（誤り訂正）符号を付加して、実質的なエラーフリーを実現することができる。
【０３２０】
また、上記構成によれば、圧縮方式に関係なく共通の誤り訂正符号を付加することでエラーフリーの環境を保証することができる。
【０３２１】
さらに、誤り訂正を共通のパケットフォーマットにすることにより相互接続のためのトータルコストを安くすることができる。すなわち、圧縮手段が種々のものに変わっても共通のリードソロモン（誤り訂正）符号とすることで、これを構成する装置の構成を共通にでき、コストを安くおさえることができる。
【０３２２】
（実施の形態１４）
図３０は本発明の第１４の実施の形態である伝送システム若しくは伝送方法及びこれを構成する送信装置若しくは送信方法と受信装置若しくは受信方法とを示した図である。なお、上記実施の形態において既に説明したものは同じ符号を用い、その説明を省略する。
【０３２３】
ここで、本実施の形態において一定の情報単位であるブロックはＮ行×Ｊ列（本実施の形態においてはＮ＝８、Ｊ＝１７０とし、（８×１７０）ビット＝１７０バイトである。）で構成されている。また所定の単位であるラインは一定の情報量以下の情報信号で構成可能であり、それを構成する各ワードはＮ行（Ｎビットの行）（Ｎは１以上の自然数であり、本実施の形態ではＮ＝８としている。）でありかつ実質的な情報信号である映像信号が配置される第１の領域とＭ行（Ｍビットの行）（Ｍは１以上の自然数であり、本実施の形態ではＭ＝２である。）でありかつ冗長な信号であるパリティ信号が配置される第２の領域とを有している（Ｎ＋Ｍ＝１０ビット）。例えば、送受信間の伝送速度が２７０Ｍｂｐｓの場合、１４４０ワード、３６０Ｍｂｐｓの場合、１９２０ワードである（１ワード＝１０ビット）。また、ここで所定の単位であるラインが構成可能な最大情報量すなわち一定の情報量とは、（Ｎ行×Ｉ列）ビットであり、本実施の形態ではＮ＝８であり、Ｉ＝１４４０（伝送速度が２７０Ｍｂｐｓの場合）又は１９２０（伝送速度が３６０Ｍｂｐｓの場合）である。
【０３２４】
図３０において、７０はＥＣＣエンコーダ１２の出力信号が各一定の情報単位であるブロック（Ｎ行×Ｊ列、本実施の形態では８×１７０）を単位に入力された情報信号の情報量に応じて、すなわち入力された情報信号の情報量が所定の単位であるラインを構成する各ワードのうち実質的な情報信号が配置されるＮ行（Ｎビットの行）の第１の領域を構成可能な一定の情報量（すなわち、Ｎ行×Ｉ列、本実施の形態では８×１４４０（伝送速度が２７０Ｍｂｐｓの場合）又は８×１９２０（伝送速度が３６０Ｍｂｐｓの場合））を超える場合にＥＣＣエンコーダ１２の（Ｍ行×Ｊ列）で構成される出力信号の映像信号の少なくとも一部を第２の領域に配置できるＸ−Ｙ変換手段である８−９変換手段である。この８−９変換手段７０の出力信号は同期信号付加手段１３に出力される。
【０３２５】
一方、ＥＣＣエンコーダ１２を用いない場合は、圧縮手段４の出力信号（Ｎ行×Ｊ列）を入力された情報信号の情報量に応じて、すなわち入力された情報信号の情報量が所定の単位であるラインを構成する各ワードのうち実質的な情報信号が配置されるＮ行（Ｎビットの行）の第１の領域を構成可能な一定の情報量を超える場合に圧縮手段４の出力信号の映像信号の少なくとも一部を第２の領域に配置できるＸ−Ｙ変換手段である８−９変換手段とし、この８−９変換手段７０の出力信号を同期信号付加手段１３に出力する構成とすればよい。
【０３２６】
７１は同期信号除去手段７の出力信号のうち第２の領域に渡って配置されている映像信号を第１の領域に再配置できる、すなわち、Ｎ行×Ｊ列（本実施の形態では８×１７０）の一定の情報単位であるブロックに復元できる構成としたＹ−Ｘ変換手段である９−８変換手段である。この９−８変換手段７１の出力信号はＥＣＣデコーダ１４に出力する。
【０３２７】
一方、ＥＣＣデコーダ１４を用いない場合は、同期信号除去手段７の出力信号のうち第２の領域に配置されている映像信号を第１の領域のみに再配置できる、すなわち、Ｎ行×Ｊ列（本実施の形態では８×１７０）の一定の情報単位であるブロックに復元できる構成としたＹ−Ｘ変換手段である９−８変換手段とし、この９−８変換手段７１の出力信号を伸張手段１１に出力する構成とすればよい。
【０３２８】
すなわち、送信装置若しくは送信方法においては、上記に記載した（実施の形態１）又は（実施の形態２）において、一定の情報単位であるブロックはＮ行（Ｎビットの行）（本実施の形態においてはＮ＝８とし、８ビットの行である。）×Ｊ列で構成されている。また所定の単位であるラインは一定の情報量以下の情報信号で構成可能であり、それを構成する各ワードはＮ行であるＮビット（Ｎは１以上の自然数）でありかつ実質的な情報信号である映像信号が配置される第１の領域とＭ行（Ｍは１以上の自然数）でありかつ冗長な信号であるパリティ信号などが配置される第２の領域とを有している場合であって、入力された情報信号の情報量に応じて、すなわち入力された情報信号の情報量が所定の単位であるラインを構成する各ワードのうち実質的な情報信号が配置されるＮビットの第１の領域を構成可能な一定の情報量を超える場合に実質的な情報信号である映像信号の少なくとも一部を第２の領域に配置可能な構成としている。
【０３２９】
一方、受信装置若しくは受信方法においては、上記に記載した（実施の形態１）又は（実施の形態２）において、一定の情報単位であるブロックはＮ行（Ｎビットの行）（本実施の形態においてはＮ＝８である。）×Ｊ列で構成されている。また所定の単位であるラインは一定の情報量以下の情報信号で構成可能であり、それを構成する各ワードはＮ行（Ｎビットの行）（Ｎは１以上の自然数）でありかつ実質的な情報信号である映像信号が配置される第１の領域とＭ行（Ｍは１以上の自然数）でありかつ冗長な信号であるパリティ信号などが配置される第２の領域とを有する場合であって、第２の領域に渡って配置された実質的な情報信号である映像信号を第１の領域のみに再配置できる、すなわち、Ｎ行（Ｎビットの行）（本実施の形態では８ビットの行）×Ｊ列の一定の情報単位であるブロックに復元できる構成としている。
【０３３０】
このような送信装置若しくは送信方法と受信装置若しくは受信方法とにより伝送路を介して伝送システム又は伝送方法を構成している。
【０３３１】
以上のような伝送システムにおいて図３１を用いてその動作を説明する。
【０３３２】
図３１は本発明の第１４の実施の形態である伝送システムの一定の情報単位であるブロックにおけるデータ形式を表した図である。
【０３３３】
図３０において、送信装置若しくは送信方法では、デジタル映像入力信号は圧縮手段４に入力されて情報量が圧縮される。圧縮手段４の出力信号はＥＣＣエンコーダ１２に入力され、ＥＣＣエンコーダ１２において各々の情報信号に誤り訂正符号が付される。ＥＣＣエンコーダ１２の出力信号はＸ−Ｙ変換手段である８−９変換手段７０に入力され、ここで、入力された情報信号の情報量に応じて、すなわち入力された情報信号の情報量が所定の単位であるラインを構成する各ワードのうち実質的な情報信号が配置されるＮ行（Ｎビットの行）の第１の領域を構成可能な一定の情報量を超える場合には、図３１に示すようにＥＣＣエンコーダ１２の出力信号の各ブロックにおいて、第１の領域（Ｂ０〜Ｂ７の領域に相当する）にのみ存在する映像信号（図３１（ａ）参照）の少なくとも一部を第２の領域（Ｂ８又はＢ８、Ｂ９に相当する）のパリティ信号が存在する領域に配置する（図３１（ｂ）参照）。この際、第２の領域に存在しているパリティ信号は破棄する。 また、パリティ信号が存在する領域に配置した際に第１の領域に空きが生じた場合は擬似信号（ダミー信号）を挿入する。この後、同期信号付加手段１３に信号が出力される。
【０３３４】
一方、入力された情報信号の情報量が所定の単位であるラインを構成する各ワードのうち実質的な情報信号が配置されるＮ行（Ｎビットの行）の第１の領域を構成可能な一定の情報量を超えない場合にはＥＣＣエンコーダ１２の出力信号をそのまま同期信号付加手段１３に出力する。
【０３３５】
一方、受信装置若しくは受信方法では、受信信号のうち同期信号除去手段７で同期信号が除去された後、同期信号除去手段７の出力信号は９−８変換手段７１において、第２の領域に渡って配置されている映像信号があれば第１の領域に再配置できる、すなわち、Ｎ行（Ｎビットの行、本実施の形態では８ビット）×Ｊ列の一定の情報単位であるブロックに復元できる構成、すなわち、送信側で８−９変換する際の規則に従って逆変換を行い、８−９変換が行われる前の状態と同様の状態に復元する。９−８変換手段７１の出力信号はＥＣＣデコーダ１４でブロック毎に付加された誤り訂正符号に基づいて信号の誤り訂正が行われる。この後、ＥＣＣデコーダ１４の出力信号は、伸張手段１１によって伸張されてデジタル映像出力信号となる。
【０３３６】
このような構成にすることにより、入力される情報信号が多い場合であって、所定の単位で送受信不可能な場合にもある程度対応することができる。
【０３３７】
ここで、図３１においてＴＹＰＥとは、圧縮データのタイプを表しおり、例えば、ＤＶＣＰＲＯは２２１ｈとなっている。また、ＭＰＥＧはＭＰＥＧ用のタイプが付される。。つぎに、ＲＥＶは、Ｒｅｓｅｒｖｅｄ（リザーブ）の略であり、規格上将来のために新たなビット定義を行えるように、またユーザーが勝手に使用しないようにリザーブしているエリアである。つぎに、ＳＴとは、Ｓｉｇｎａｌ Ｔｙｐｅの略であり、信号形式を表している。ＤＶＣＰＲＯでもフィールド周波数が５０Ｈｚ／６０Ｈｚ（５９．９４Ｈｚ）の形式のものや、輝度信号と色信号のサンプル数による違いなど、同じＤＶＣＰＲＯでも様々な信号形式を識別するためのものである。ＴＴとは、Ｔｒａｎｓｍｉｓｓｉｏｎ Ｔｙｐｅの略であり、転送形式を表している。通常再生の１倍速転送だけでなく４倍速転送や８倍速転送など様々な転送形式を識別するとともに、フレームの識別を行うためのものである。
【０３３８】
なお、本実施の形態では（実施の形態１）又は（実施の形態２）にＸ−Ｙ変換手段７０及びＹ−Ｘ変換手段７１を設けたものであるが、他の実施の形態に設けても同様の効果が得られる。
【０３３９】
また、本実施の形態では、Ｘ−Ｙ変換手段７０及びＹ−Ｘ変換手段７１はＸ−Ｙ変換及びＹ−Ｘ変換するかしないかを切り替えられる構成としているが、常にＸ−Ｙ変換及びＹ−Ｘ変換する構成としてもよい。
【０３４０】
【発明の効果】
以上のような構成にすることにより、１つの集合情報単位に多数の情報信号を含めることができ信号の伝送を効率よく行うことができる。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図
【図２】本発明の第１の実施の形態である伝送システムの１つの集合情報単位におけるデータ形式を表した図
【図３】本発明の第２の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図
【図４】本発明の第２の実施の形態である伝送システムの１つの集合情報単位におけるデータ形式を表した図
【図５】（ａ）は非圧縮系において１カ所で誤りが起きた場合を表した概念図
（ｂ）は圧縮系において１カ所で誤りが起きた場合であって、画素の正方形の領域を１つのエリアとして扱った場合を示す概念図
（ｃ）は圧縮系において１カ所で誤りが起きた場合であって、画素の１ラインの領域を１つのエリアとして扱った場合を示す概念図
（ｄ）は圧縮系において１カ所で誤りが起きた場合であって、画面全体の領域を１つのエリアとして扱った場合を示す概念図
【図６】本発明の第３の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図
【図７】本発明の第３の実施の形態である伝送システムの１つの集合情報単位におけるデータ形式を表した図
【図８】本発明の第４の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図
【図９】本発明の第４の実施の形態である伝送システムの１つの集合情報単位におけるデータ形式を表した図
【図１０】本発明の第５の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図（時間情報付加手段２８においてＥＣＣエンコーダ１２に入力された入力信号の時間情報を扱う場合）
【図１１】本発明の第５の実施の形態である伝送システムの１つの集合情報単位におけるデータ形式を表した図
【図１２】本発明の第６の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図（時間情報付加手段３９においてＥＣＣエンコーダ１２が出力した出力信号の時間情報を扱う場合）
【図１３】本発明の第６の実施の形態である伝送システムの１つの集合情報単位におけるデータ形式を表した図
【図１４】本発明の第７の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図（時間情報付加手段２８においてＥＣＣエンコーダ１２に入力された入力信号の時間情報を扱う場合）
【図１５】本発明の第７の実施の形態である伝送システムの送信側の１つの集合情報単位におけるデータ形式を表した図
【図１６】本発明の第８の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図（時間情報付加手段３９においてＥＣＣエンコーダ１２が出力した出力信号の時間情報を扱う場合）
【図１７】本発明の第８の実施の形態である伝送システムの受信側の１つの集合情報単位におけるデータ形式を表した図
【図１８】本発明の第７の実施の形態又は第８の実施の形態である伝送システムの別の１つの集合情報単位におけるデータ形式を表した図
【図１９】本発明の第９の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図（時間情報付加手段２８においてＥＣＣエンコーダ１２に入力された入力信号の時間情報を扱う場合）
【図２０】本発明の第９の実施の形態である伝送システムの送信側の１つの集合情報単位におけるデータ形式を表した図
【図２１】本発明の第１０の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図（時間情報付加手段３９においてＥＣＣエンコーダ１２が出力した出力信号の時間情報を扱う場合）
【図２２】本発明の第１０の実施の形態である伝送システムの受信側の１つの集合情報単位におけるデータ形式を表した図
【図２３】本発明の第１１の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図
【図２４】（ａ）本発明の第１１の実施の形態の圧縮信号のデータ形式を示す図
（ｂ）本発明の第１１の実施の形態の非圧縮信号のデータ形式を示す図
【図２５】本発明の第１２の実施の形態である伝送システムの１つの集合情報単位におけるデータ形式を表した図
【図２６】一般的に使用される５Ｃ２Ｖ同軸ケーブルのケーブル長と減衰量との関係を示す図
【図２７】本発明の第１３の実施の形態で用いた送信装置及び受信装置を示す図
【図２８】本発明の第１３の実施の形態で用いた信号のジッタの詳細な内容を示す図
【図２９】リードソロモン符号の誤り訂正能力を示す図
【図３０】本発明の第１４の実施の形態である伝送システム及びこれを構成する送信装置と受信装置とを示した図
【図３１】本発明の第１４の実施の形態である伝送システムの受信側の１つの集合情報単位におけるデータ形式を表した図
【図３２】従来の伝送システムを示す図
【符号の説明】
１ 離散コサイン変換手段
２ 量子化手段
３ 可変長符号化手段
４ 圧縮手段
５、１３ 同期信号付加手段
６ 伝送路
７ 同期信号除去手段
８、１５、１９、２５ 可変長復号化手段
９ 逆量子化手段
１０ 離散コサイン逆変換手段
１１ 伸張手段
１２、１７、２２ ＥＣＣエンコーダ
１４ ＥＣＣデコーダ
１６、２１、２３ 合成手段
１８ 分配手段
２０ シャフリング手段
２４ デシャフリング手段
２６ 非圧縮手段
２７ 非伸張手段
２８ 時間情報付加手段
２９、３１ バッファ
３０ 時間情報再生手段[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a transmitting device and a receiving device that handle digital signals for transmitting digital video and audio signals, and a transmission system including the same.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a transmitter and a receiver for transmitting signals such as digital video and audio have been described in Japanese Patent Application Laid-Open No. 2-270430.
[0003]
FIG. 31 is a schematic block diagram showing a transmission system using a conventional digital signal transmitting apparatus and receiving apparatus. In FIG. 31, reference numeral 103 denotes a synthesizing circuit, which is a 16-bit signal supplied to a digital audio signal input terminal 101. The bit data of the long data and the plurality of control signals supplied to the control signal input terminal 102 are rearranged in a predetermined order. Reference numeral 104 denotes an encoding circuit. The encoding circuit 104 generates an 8-bit error detection and correction code for a total of 17 bits of data, and adds it to a predetermined area to generate 25-bit serial data. Reference numeral 105 denotes a modulation / synchronization adding circuit. The above-mentioned 25-bit serial data is input. The modulation / synchronization adding circuit 105 first generates and adds a parity check bit P, and then performs biphase mark modulation. Further, a preamble SYNC as a synchronizing signal is added and the data is output as formatted data. The above-mentioned terminals 101 and 102 and each of the circuits 103, 104 and 105 constitute a digital signal transmitting apparatus A.
[0004]
A transmission line 106 uses a coaxial cable or an optical fiber cable. Reference numeral 107 denotes a synchronization detection / demodulation circuit to which data transmitted via the transmission path 106 is input. Here, a synchronous preamble signal SYNC is detected and a clock is extracted, and demodulation is performed using this clock. The demodulated data is subjected to error detection using the parity check bit P. Reference numeral 108 denotes a decoding circuit which corrects an error generated on the transmission line 106 by using an error correction code check, and interpolates an error which can be detected but cannot be corrected as necessary. Output a flag for performing such processing.
[0005]
Reference numeral 109 denotes a separation circuit, which separates the digital audio sample and the control signal and outputs the separated signals from output terminals 110 and 111. The above-described circuits 107, 108, 109 and terminals 110, 111 constitute a digital signal receiving apparatus B.
[0006]
[Problems to be solved by the invention]
However, in the above-mentioned conventional transmission system, a large number of information signals cannot be included in one set information unit, and the information signals cannot be transmitted efficiently.
[0007]
Therefore, the transmission apparatus or the transmission method, the reception apparatus or the reception method, and the transmission system or the transmission method including the transmission apparatus or the transmission method according to the present invention can include a large number of information signals in one aggregate information unit, and efficiently transmit the information signals. The purpose is to:
[0008]
[Means for Solving the Problems]
In order to solve the above problem, a transmitting device of the present invention compresses an information amount of an input information signal and outputs the information signal for each fixed information unit, and collects and outputs a plurality of output signals of the compression unit. A synchronizing signal adding means for adding one synchronizing signal; and transmitting an output signal of the synchronizing signal adding means.
[0009]
On the other hand, the receiving apparatus of the present invention receives one synchronization signal and a plurality of units of compressed information signals as one aggregate information unit, and removes a synchronization signal from the received signals. And a decompression means for decompressing the compressed video signal among the output signals of the signal removal means for each unit.
[0010]
A transmission system was constructed with such a transmitting device and a receiving device.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0012]
(Embodiment 1)
FIG. 1 is a diagram illustrating a transmission system according to a first embodiment of the present invention, and a transmission device and a reception device that constitute the transmission system.
[0013]
In FIG. 1, reference numeral 1 denotes a discrete cosine transform (spatial space), which is a type of orthogonal transform, of an input digital video input signal in units of one block (one block = 77 bytes in the present embodiment) as a fixed information unit. Discrete Cosine Transform (DCT) means for converting coordinate values into frequencies and outputting the converted values. The pixel values (for example, luminance values) of video signals randomly distributed before the transform by the means. ) Makes it possible to perform an information compression operation by an operation of removing a high-frequency term later, utilizing the property that large terms are concentrated on a low-frequency term after conversion. Numeral 2 denotes quantization means for quantizing (terminating the word length) the input output signal of the discrete cosine transform means 1 for each block, and divides each coefficient of the output signal of the discrete cosine transform means 1 by a certain divisor (quantum). ), And performs an operation of rounding the remainder. Reference numeral 3 denotes a variable-length encoding unit that converts an input output signal of the quantization unit 2 into a variable-length code. The variable-length encoding unit 3 determines the output signal of the quantization unit 2 in advance based on an appearance probability or the like. Convert to a variable length code with an inconsistent length. A compression unit 4 for compressing the information amount of the digital video signal input by the discrete cosine transformation unit 1, the quantization unit 2, and the variable length encoding unit 3 and outputting the compressed information amount for each block which is a constant information unit. I have. Reference numeral 5 denotes a synchronizing signal adding means for collecting the input output signals of the variable-length coding means for a plurality of blocks and adding a synchronizing signal to the collected signals. The information is output (transmitted) to the coaxial cable 6, which is a transmission path, as an aggregate information unit.
[0014]
Reference numeral 7 denotes a synchronization signal removing unit that removes a synchronization signal from the input (received) signal of one set information unit. Reference numeral 8 denotes a variable-length decoding unit that decodes the input output signal (variable-length code) of the synchronization signal removing unit 7 into a digital signal before being subjected to variable-length encoding. (Long code) is decoded into a digital video signal before being subjected to variable length coding in accordance with a rule determined in advance based on an appearance probability or the like.
[0015]
Numeral 9 denotes an inverse quantization means for performing an inverse quantization (returning the word length to the original) of the input output signal of the variable length decoding means 8 for each block. A quantization step is applied to each coefficient for each block. Reference numeral 10 denotes an inverse discrete cosine transform (IDCT) unit that performs an inverse discrete cosine transform (converts a frequency to a spatial coordinate value) on the input output signal of the inverse quantization unit 9 and outputs the result. The variable length decoding means 8, the inverse quantization means 9, and the inverse discrete cosine transform means 10 constitute a decompression means 11.
[0016]
That is, in the transmitting apparatus or the transmitting method of the present invention, one synchronous signal and a plurality of video signals, which are information signals of one block, which is a constant information unit, are collected and output (transmitted) as one aggregate information unit. are doing. In the transmitting apparatus or the transmitting method according to the present embodiment, a digital video signal is used as an information signal, and the information amount of the digital video signal is compressed.
[0017]
On the other hand, in the receiving apparatus or the receiving method of the present invention, one synchronization signal and a plurality of video signals, which are information signals of one block, which is a fixed information unit, are collected and input (received) as one set information unit. are doing. In the receiving apparatus or the receiving method according to the present embodiment, a digital video signal is used as an information signal, and the digital video signal is expanded.
[0018]
Such a transmission device or transmission method and a reception device or reception method constitute a transmission system or transmission method via a transmission path.
[0019]
The transmission system or transmission method as described above, and the data format transmitted and received by the transmission device or transmission method and the reception device or reception method that constitute the transmission system or transmission method will be described with reference to FIG.
[0020]
FIG. 2 is a diagram showing a data format in one set information unit. In FIG. 2A, the information signal a (video signal a), the information signal b (video signal b), the information signal c (video signal c), and the information signal d (video signal d) represent the information amount of the video input signal. It is compressed and divided into blocks, and represents an information signal of one block. A plurality of information signals of this one block are collected, and one synchronization signal is added thereto to form a signal of one set information unit. In FIG. 2 (a), the synchronization signal and the information signal do not occupy all of one set information unit, but as shown in FIG. 2 (b), the synchronization signal and the information signal form one set information unit. You may make it occupy all. Further, as shown in FIG. 2C, a synchronization signal, an information signal, and other necessary information that is not a video signal itself but are required as an auxiliary data signal are included in one set information unit, and are transmitted and received for each set information unit. It doesn't matter.
[0021]
With such a configuration, a large number of information signals can be included in one set information unit, and signal transmission can be performed efficiently.
[0022]
In the present embodiment, the compression means 4 is constituted by the discrete cosine transform means 1, the quantization means 2, and the variable length coding means 3, but any other means may be used as long as it can compress the information signal.
[0023]
Further, in the present embodiment, a coaxial cable is used as the transmission path, but it may be another cable such as an optical fiber, a parallel feeder, another conductor, or a wireless cable such as a communication cable.
[0024]
Further, in the present embodiment, a video signal is used as an information signal, but similar effects can be obtained with other information signals.
[0025]
(Embodiment 2)
FIG. 3 is a diagram showing a transmission system or a transmission method according to a second embodiment of the present invention, and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system or the transmission method. Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0026]
In FIG. 3, reference numeral 12 denotes an ECC (error correction code) encoder for adding an error correction code to a video signal for each block, which is a constant information unit of the input output signal of the variable length coding unit 3. The receiving apparatus detects or corrects a code error based on the error correction code. In this embodiment, a Reed-Solomon code is used as an error correction code. Reference numeral 13 denotes a synchronizing signal adding means for collecting the input output signals of the ECC encoder 12 for a plurality of blocks and adding a synchronizing signal to the collected signals. The signal is output (transmitted) to the coaxial cable 6, which is a transmission line, as a unit.
[0027]
An ECC (error correction code) decoder 14 detects and corrects an error of a coded video signal based on an error correction code for each block, which is a constant information unit of the input output signal of the synchronization signal removing means 7. It is. Reference numeral 15 denotes a variable-length decoding unit that decodes the input output signal (variable-length code) of the ECC decoder 14 into a digital signal before being subjected to variable-length coding, and converts the output signal (variable-length code) of the ECC decoder 14 into a digital signal. The digital video signal is decoded into a digital video signal before being subjected to variable-length coding according to a rule determined based on an appearance probability or the like in advance.
[0028]
That is, in the transmitting apparatus or the transmitting method of the present invention, a compression unit 4 for compressing the information amount of a video signal which is an input information signal and outputting the compressed information amount for each fixed information unit, and an output signal of the compression unit 4 in n units (N is a natural number of 1 or more, and n = 1 in the present embodiment). An ECC encoder 12 that collects and adds an error correction code and a plurality of output signals of the ECC encoder 12 are collected and synchronized with one unit. And a synchronizing signal adding means 13 for adding a signal. The output signal of the synchronizing signal adding means 13 is transmitted. In further summary, a predetermined unit of information signal (a video signal of one block in the present embodiment) is changed every n units (n is a natural number of 1 or more, and n = 1 in the present embodiment). An error correction signal is added to form a small set information unit, and one synchronization signal and a plurality of information signals of the small set information unit are transmitted as one set information unit.
[0029]
On the other hand, in the receiving apparatus or the receiving method of the present invention, one synchronization signal and a video signal which is a plurality of units of compressed information signals are received as one aggregate information unit, and the synchronization signal among the received signals is A synchronous signal removing unit for removing, and an ECC decoder for correcting an error of a video signal based on the error correcting code for each small set information unit to which an error correcting code is added among output signals of the synchronous signal removing unit. And an expansion means 11 for expanding the compressed video signal among the output signals of the ECC decoder 14 for each unit. In more detail, one synchronization signal and a plurality of information signals of a predetermined information unit are received as one aggregate information unit, and an information signal of a predetermined unit (in this embodiment, one block of one block) is received. The video signal) is configured to perform signal error correction based on the error correction code for each unit to which the error correction signal is added (in the present embodiment, for each block).
[0030]
Such a transmission device or transmission method and a reception device or reception method constitute a transmission system or transmission method via a transmission path.
[0031]
The transmission system or transmission method as described above, and the data format transmitted and received by the transmission device or the transmission method and the reception device or the reception method constituting the transmission system or the transmission method will be described with reference to FIG.
[0032]
FIG. 4 is a diagram showing a data format in one set information unit. 4A, the information signal a (video signal a), the information signal b (video signal b), the information signal c (video signal c), and the information signal d (video signal d) represent the information amount of the video input signal. It is compressed and divided into blocks, and represents an information signal of one block. A plurality of signals obtained by adding an error correction signal (error correction code) to each of the information signals of one block are collected, and one synchronizing signal is added thereto to form a signal of one aggregate information unit. In FIG. 4A, the signal information signal obtained by adding the synchronization signal and the error correction signal does not occupy all of one set information unit, but as shown in FIG. May be made to occupy all of one set information unit. Further, as shown in FIG. 4 (c), even if a synchronization signal, an information signal, an error correction signal, and other necessary information other than the video signal itself are included and transmitted as an auxiliary data signal in one collective information unit, I don't care.
[0033]
With such a configuration, when the frequency of occurrence of errors is reduced and a signal is output (transmitted) without compressing the information signal (hereinafter, referred to as an uncompressed system), some errors are hardly noticeable visually. However, when an information signal is compressed and a signal is output (transmitted) (hereinafter, referred to as a compression system), the frequency of occurrence of a non-negligible error can be reduced.
[0034]
For example, when an error occurs in one location in one area, the error location is one point in the non-compression system as shown in FIG. 5A, and this error is hardly noticeable visually. As shown in (b) to FIG. 5 (d), the error location extends over the entire area, and the error cannot be ignored. FIG. 5A is a conceptual diagram showing a case where an error occurs in one place in the non-compression system, and FIG. 5B shows a case where an error occurs in one place in the compression system. FIG. 5C is a conceptual diagram showing a case where a square area is treated as one area. FIG. 5C shows a case where an error occurs in one place in the compression system, and an area of one line of pixels is regarded as one area. FIG. 5D is a conceptual diagram showing a case where an error has occurred at one place in the compression system, and a case where the entire screen area is treated as one area. In each case, a black point indicates a portion where an error has occurred, and a hatched portion indicates a region affected by an image due to a portion where an error has occurred (a black point portion).
[0035]
In particular, in a coaxial cable or an optical cable representing a system for transmitting a signal by wire (hereinafter, referred to as a wire system), the frequency of occurrence of an error in a transmission path is generally 1 × 10 ^-12 Conventionally, it has been considered that no error occurs visually in an uncompressed system (error-free). However, in the present invention, one error is generated as described above when an error occurs in a compressed signal. In view of the fact that errors affect other areas, the frequency of occurrence of errors can be further reduced to such an extent that such effects can be substantially ignored.
[0036]
In this embodiment, an error correction code is added to the video signal for each block, but as shown in FIGS. 4D and 4E, an error occurs every two blocks of the information signal (two units, that is, n = 2). The same effect can be obtained by adding an error correction code to a video signal of a plurality of units, such as adding a correction signal.
[0037]
(Embodiment 3)
FIG. 6 is a diagram showing a transmission system or a transmission method according to a third embodiment of the present invention, and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system or the transmission method. Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0038]
In FIG. 6, reference numerals 1a, 1b and 1c denote discrete cosine transform means, 2a, 2b and 2c denote quantization means, and 3a, 3b and 3c denote variable length coding means. Is configured. Reference numeral 16 denotes a synthesizing unit for temporarily storing the output signals of the variable length encoding units 3a, 3b, and 3c, sequentially selecting the output signals of the variable length encoding units 3a, 3b, and 3c, and serially outputting the output signals. . Reference numeral 17 denotes an ECC (error correction code) encoder for adding an error correction code to a video signal for each block, which is a constant information unit, of the output signal of the synthesizing unit 16, and is based on the error correction code. Thus, the receiving device detects or corrects a code error. In this embodiment, a Reed-Solomon code is used as an error correction code.
[0039]
19a, 19b and 19c are variable length decoding means, 9a, 9b and 9c are inverse quantization means, 10a, 10b and 10c are inverse discrete cosine transform means, and these constitute expansion means 11a to 11c. Is done. Reference numeral 18 denotes distribution means for distributing the input output signal of the ECC decoder 14 to each expansion means in accordance with the rule selected by the synthesis means 16. Reference numerals 19a to 19c denote variable-length decoding means for decoding the input output signal (variable-length code) of the distributing means 18 into a digital signal before being subjected to variable-length encoding, and output signals (variable signals) of the distributing means 19a to 19c. (Long code) is decoded into a digital video signal before being subjected to variable length coding in accordance with a rule determined in advance based on an appearance probability or the like.
[0040]
That is, in the transmitting apparatus or the transmitting method of the present invention, the transmitting device or the transmitting method includes a plurality of compressing units 4a to 4c for compressing the information amount of the input video signal and outputting the compressed information amount for each block as a constant information unit. A selecting means for selecting each of the output signals of each block to 4c and outputting the signals in series, and an ECC encoder for collecting the output signals of the combining means in n units (n is a natural number of 1 or more) and adding an error correction signal thereto And a synchronizing signal adding means for collecting a plurality of units of the output signal of the ECC encoder and adding one synchronizing signal thereto, and transmitting the output signal of the synchronizing signal adding means. There are a plurality of types of video signals as information signals.
[0041]
On the other hand, in the receiving apparatus or the receiving method of the present invention, a synchronization signal for receiving one synchronization signal and a plurality of units of compressed video signals as one aggregate information unit and removing the synchronization signal from the received signals Removing means 7, an ECC decoder 14 for performing error correction of the signal based on the error correction signal for each unit to which the error correction signal is added among the output signals of the synchronization signal removing means 7, and a combined output signal of the ECC decoder 14 Receiving means or a receiving method comprising a distributing means 18 for distributing according to the set rules, and decompressing means 11a to 11c for decompressing the video signal of which the information amount is compressed among the output signals of the distributing means 18 for each information unit. There are a plurality of types of information signals that are information signals.
[0042]
Such a transmission device or transmission method and a reception device or reception method constitute a transmission system or transmission method via a transmission path.
[0043]
The operation of the above transmission system or transmission method will be described below.
[0044]
That is, in the transmission apparatus or the transmission method of the present invention, the digital video input signals a to c are input to the compression units 4a to 4c in parallel, respectively, and the information amount is compressed and output for each block. The output signals of the compression units 4a to 4c are temporarily stored by the synthesizing unit 16, sequentially selected for each block, and output to the ECC encoder 17 in series. An error correction code is added to the output signal of the synthesizing unit 16 for each block of n units by the ECC encoder 17, and a synchronizing signal is added by the synchronizing signal adding unit 13.
[0045]
On the other hand, according to the receiving apparatus or the receiving method of the present invention, the synchronization signal is removed from the received signal by the synchronization signal removing unit 7, and the ECC decoder 14 performs error correction of the signal based on the error correction code. The output signal of the ECC decoder 14 is distributed by the distributing means 18 to each decompressing means in accordance with the rule selected by the synthesizing means 16, and is input to the decompressing means 11a to 11c in parallel. Thereby, the output signal of the distribution means 18 is expanded to become digital video output signals a to c.
[0046]
The transmission system or transmission method as described above, and the data format transmitted and received by the transmission device or transmission method and the reception device or reception method constituting the transmission system or transmission method will be described with reference to FIG.
[0047]
FIG. 7 is a diagram showing a data format in one set information unit. In FIG. 7A, information signal a (video signal a), information signal b (video signal b), and information signal c (video signal c) are information of video input signal a, video input signal b, and video input signal c. It is a signal obtained by compressing the amount and blocking, and represents an information signal of one block. A plurality of signals obtained by adding an error correction signal (error correction code) to each of the information signals of one block are collected, and one synchronizing signal is added thereto to form a signal of one aggregate information unit. In FIG. 7 (a), the information signal obtained by adding the synchronization signal and the error correction signal does not occupy all the one set of information units, but as shown in FIG. The added information signal may occupy all of one set information unit. Further, as shown in FIG. 7 (c), even when a synchronization signal, an information signal, an error correction signal, and other necessary information other than the video signal itself are included and transmitted as an auxiliary data signal in one set information unit, I don't care.
[0048]
With such a configuration, a plurality of information (signal) sources can be included in one aggregate information unit, and signal transmission can be performed efficiently.
[0049]
Note that the synthesizing unit 16 is configured to attach an identification signal for identifying which video input signal of the digital video input signals a to c corresponds to each block, which is a predetermined unit. The video signals a to c may be distributed based on the attached identification signal.
[0050]
In this embodiment, an error correction code is added to a video signal for each block. However, as shown in FIGS. 7D and 7E, an error correction signal is added for every two blocks (two units) of an information signal. The same effect can be obtained even if an error correction code is added to a video signal for each of a plurality of units.
[0051]
Further, in this embodiment, an example in which an error correction code is used based on (Embodiment 2) has been described. However, a similar effect can be obtained by using an error correction code (Embodiment 1).
[0052]
(Embodiment 4)
FIG. 8 is a diagram showing a transmission system or a transmission method according to a fourth embodiment of the present invention, and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system or the transmission method. Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0053]
In FIG. 8, reference numeral 20 denotes a shuffling means for outputting a digital audio input signal per frame unit in a time-series arrangement within the frame unit and outputting the signal. Reference numeral 21 denotes a synthesizing unit that temporarily stores the output signal of the variable length encoding unit 3 and the output signal of the shuffling unit 20 that are input, sequentially selects the serial signals, and outputs the signals in series.
[0054]
Reference numeral 23 denotes a distribution unit that distributes the input output signal of the ECC decoder 14 to the deshuffling unit 24 or the expansion unit 11 in accordance with the rule selected by the combining unit 21. Reference numeral 24 denotes an input output signal of the distribution unit 23, which is a deshuffling unit for returning the digital audio input signal per frame unit to audio data in which the time-series arrangement has been replaced in the frame unit. , Constitute the non-expansion means 27.
[0055]
That is, in the transmission device or the transmission method, the compression means 4 for compressing the information amount of the video signal which is the input information signal and outputting the information signal for each fixed information unit, and compressing the audio signal which is the input information signal. And a synthesizing unit 21 for selecting each output signal of the compressing unit 4 and the non-compressing unit 26 for each block as a certain information unit, outputting the signals in series, and outputting the signals in series. And an ECC encoder 22 for collecting output signals of the synthesizing means 21 in units of n (n is a natural number of 1 or more) and adding an error correction signal thereto, and collecting a plurality of blocks of output signals of the ECC encoder 22 and adding one synchronizing signal thereto. It has a synchronizing signal adding means 13 for transmitting the output signal of the synchronizing signal adding means 13. In that the compressed information signal and the information of the block is a multi-address unit is composed of the non-compressed information signals of the block which is a constant information unit that has not been compressed.
[0056]
On the other hand, in the receiving apparatus or the receiving method, the synchronous signal removing means 7 receives one synchronous signal and a plurality of blocks of compressed information signals as one collective information unit and removes the synchronous signal from the received signals. And an ECC decoder 14 for performing error correction of the signal based on the error correction signal for each unit to which the error correction signal is added among the output signals of the synchronization signal removing means 7, and a rule in which the output signal of the ECC decoder 14 is synthesized. , An expansion unit 11 for expanding the information signal of the output signal of the distribution unit 23 in which the information amount is compressed in units, and an information amount of the output signal of the distribution unit 23 in which the information amount is compressed. And a non-expansion means 27 for outputting an unvoiced audio signal. The information signal is characterized in that the information signal is a compressed information signal of a fixed information unit and the information amount is reduced. There is to be composed of a non-compressed information signals of a predetermined information unit which has not been reduced.
[0057]
Such a transmission device or transmission method and a reception device or reception method constitute a transmission system or transmission method via a transmission path.
[0058]
The operation of the above transmission system or transmission method will be described below.
[0059]
That is, in the transmission device or the transmission method, the digital video input signal is input to the compression unit 4 and the amount of information is compressed. On the other hand, the digital audio input signal is output from the shuffling means without compressing the information amount. Output signals from the compression means 4 and the shuffling means 20 are temporarily stored by the synthesizing means 21, sequentially selected, and output to the ECC encoder 22 in series. An error correction code is added to the output signal of the synthesizing unit 21 by the ECC encoder 22, and a synchronizing signal is added by the synchronizing signal adding unit 13.
[0060]
On the other hand, in the receiving apparatus or the receiving method, the synchronization signal is removed from the received signal by the synchronization signal removing unit 7, and the ECC decoder 14 performs signal error correction based on the error correction code. The output signal of the ECC decoder 14 is distributed by the distribution unit 23 to the expansion unit 11 or the deshuffling unit 24 according to the rule selected by the synthesizing unit 21, and is input to the expansion unit 11 or the deshuffling unit 24 in parallel. Thereby, the video signal among the output signals of the distribution unit 23 is expanded to become a digital video output signal, and the audio signal is not expanded and becomes a digital audio output signal.
[0061]
The transmission system or the transmission method as described above, and the data format transmitted and received by the transmission device or the transmission method and the reception device or the reception method constituting the transmission system or the transmission method will be described using FIG.
[0062]
FIG. 9 is a diagram showing a data format in one set information unit. In FIG. 9A, a compressed information signal a (video signal a), a compressed information signal b (video signal b), and a compressed information signal c (video signal c) are signals obtained by compressing the information amount of a video input signal into blocks. And the uncompressed information signal (audio signal) is a signal obtained by blocking the audio input signal without compression, and represents one block of the information signal. A plurality of information signals obtained by adding an error correction signal (error correction code) to each of the information signals of one block are collected, and one synchronization signal is added thereto to form a signal of one aggregate information unit. In FIG. 9A, the information signal to which the synchronization signal and the error correction signal are added does not occupy all of one set information unit, but as shown in FIG. The added information signal may occupy all of one set information unit. Further, as shown in FIG. 9 (c), even if a synchronization signal, an information signal, an error correction signal, and other information that is not a video signal itself but are required are included and transmitted as an auxiliary data signal in one collective information unit. I don't care.
[0063]
With such a configuration, a plurality of information (signal) sources can be included in one aggregate information unit, and signal transmission can be performed efficiently.
[0064]
Note that the synthesizing unit 21 is configured to attach an identification signal for identifying which video input signal of the digital video input signals a to c corresponds to each block as a predetermined unit. The video signals a to c may be distributed based on the attached identification signal.
[0065]
In this embodiment, the error correction code is added to the video signal for each block. However, as shown in FIGS. 9D and 9E, the error correction signal is added for every two blocks (two units) of the information signal. The same effect can be obtained even if an error correction code is added to the video signal or the audio signal for each of a plurality of units.
[0066]
Further, in this embodiment, an example in which an error correction code is used based on (Embodiment 2) has been described. However, a similar effect can be obtained by using an error correction code (Embodiment 1).
[0067]
(Embodiment 5)
FIG. 10 is a diagram showing a transmission system or a transmission method according to a fifth embodiment of the present invention, and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system or the transmission method. Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0068]
In FIG. 10, reference numeral 28 denotes information indicating the time when the input signal to the ECC encoder 12 was input to the ECC encoder 12 (hereinafter, referred to as time information (Time Stamp) (hereinafter, abbreviated as TS)) in a fixed information unit (hereinafter, referred to as TS). , A block), and adds time information to the input signal of the ECC encoder 12 for each block and inputs the signal to the ECC encoder 12. Here, the ECC encoder 12 adds time information to each block of the input signal of the ECC encoder 12, and outputs a signal to which an error correction code is added to each block to which the time information is added, to the buffer 29. Reference numeral 29 denotes a buffer provided between the ECC encoder 12 and the synchronizing signal adding means 13 and provided for temporarily storing the output signal of the ECC encoder 12. The buffer 29 stores the output signal of the ECC encoder 12, The information accumulated within a certain time is output to the synchronization signal adding means 13 as one set unit. In this embodiment, the fixed time is one line cycle. It should be noted that the buffer 29 may be configured such that, when an amount of information corresponding to one collective information unit is accumulated, the collective information unit is collected and output to the synchronization signal adding means 13.
[0069]
On the other hand, when the ECC encoder 12 is not used, the time information adding means 28 is configured to recognize, for each block, the time information (TS) at which the output signal of the compression means 4 is output. Is added to the time information and output to the buffer 29. The buffer 29 is provided between the compression means 4 and the synchronizing signal adding means 13, temporarily stores the output signal of the compression means 4, and the buffer 29 stores the output signal of the buffer 29, and stores the information stored within a predetermined time. What is necessary is just to set it as the structure which outputs to the synchronous signal addition means 13 as one set unit.
[0070]
Reference numeral 30 denotes time information reproducing means for recognizing the time information added by the time information adding means 28 for each block. In accordance with the instruction from the time information reproducing means 30, the buffer 31 outputs the stored information signal to the expansion means 11 at a timing corresponding to the time information for each block. Reference numeral 31 denotes a buffer provided between the ECC decoder 14 and the expansion means 11 and provided for temporarily storing the output signal of the ECC decoder 14.
[0071]
On the other hand, when the ECC decoder 14 is not used, the time information reproducing means 30 recognizes the time information added by the time information adding means 28 for each block. The buffer 31 storing the output signal of the synchronizing signal removing means 7 in accordance with the instruction of the time information reproducing means 30 outputs the stored information signal at a timing corresponding to the time information for each block. The buffer 31 may be provided between the synchronizing signal removing means 7 and the decompressing means 11 to temporarily store the output signal of the synchronizing signal removing means 7.
[0072]
That is, in the transmission apparatus or the transmission method, the time when the signal is output from the compression unit 4 (when the ECC encoder 12 is not used) in the above-described (Embodiment 1) or (Embodiment 2) or the ECC encoder 12 (when the ECC encoder 12 is used), the information indicating the time at which the signal was input is recognized for each block, and the output signal of the compression means 4 (when the ECC encoder 12 is not used) or the ECC encoder 12 (when the ECC encoder 12 is used). (When used), the time information is added to the input signal for each block, and the most characteristic feature is that the time information is added to each block.
[0073]
On the other hand, in the receiving apparatus or the receiving method, the synchronization signal removing means 7 (when the ECC decoder 14 is not used) or the ECC decoder 14 (the ECC decoder 14) in the first or second embodiment described above. Is used, the information representing the time included in the output signal of each block is recognized for each block, and the synchronization signal removing means 7 (when the ECC decoder 14 is not used) or the ECC decoder 14 (the ECC decoder 14 is used) based on the time information. ) Is delayed for each block. The most characteristic feature is that the synchronization signal removing means 7 (when the ECC decoder 14 is not used) or the ECC is used based on the time information added for each block. The output signal of the decoder 14 (when the ECC decoder 14 is used) is output after being delayed for each block. It is configuration and the fact that.
[0074]
Such a transmission device or transmission method and a reception device or reception method constitute a transmission system or transmission method via a transmission path.
[0075]
The operation of the above transmission system will be described with reference to FIG.
[0076]
FIG. 11 is a diagram showing a data format in one set information unit of the transmission system according to the fifth embodiment of the present invention.
[0077]
In FIG. 11, in the transmitting apparatus or the transmitting method, the digital video input signal is input to the compression means 4 to compress the amount of information, and is output after being blocked into a certain information unit. The output signal of the compression means 4 (see FIG. 11A) is input to the ECC encoder 12. The time information adding means 28 adds time information (TS) at that time, that is, the time when the input signal of the ECC encoder 12 is input, for each block (FIG. 11B). Here, time information 1 (TS1) to time information 3 (TS3) are added to each of the information signals 1 to 3.
[0078]
Next, the ECC encoder 12 applies an error correction code to each of the information signals 1 to 3 and the time information 1 (TS1) to 3 (TS3). The output signal of the ECC encoder 12 (see FIG. 11C) is stored in the buffer 29, and the information stored within a fixed time (corresponding to one line cycle in this embodiment) is synchronized as one set unit. The signal is output to the signal adding means 13. The output signal (FIG. 11D) of the buffer 29 is output to the synchronizing signal adding means 13 and transmitted via the transmission line after the synchronizing signal is added.
[0079]
On the other hand, in the receiving apparatus or the receiving method, after the synchronization signal is removed by the synchronization signal removing unit 7 from the received signal, the output signal (FIG. 11E) of the synchronization signal removing unit 7 is output by the ECC decoder 14 for each block. The error correction of the signal is performed based on the error correction code added to. The time information reproducing means 30 transmits the information signals 1 to 3 by the buffer 31 based on the time information 1 (TS1) to the time information 3 (TS3) in the output signal (FIG. 11 (f)) of the ECC decoder 14. Each block is delayed and output so as to have the same time interval as that input to the ECC encoder 12 (FIG. 11 (g)). Thereafter, the output signal of the buffer 31 is expanded by the expansion means 11 to become a digital video output signal.
[0080]
By adopting such a configuration, the time interval at the position of the time information adding means 28 can be included in one set information unit while the time interval at the position of the time information adding means 28 is reproduced from the information transmitted in bursts on the receiving side. Can be performed efficiently.
[0081]
In the present embodiment, the time information adding means 28 is provided in (Embodiment 1) or (Embodiment 2), but the same applies to the case where the time information adding means is provided in other embodiments. The effect is obtained.
[0082]
(Embodiment 6)
FIG. 12 is a diagram illustrating a transmission system or a transmission method according to a sixth embodiment of the present invention, and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system or the transmission method. Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0083]
In FIG. 12, reference numeral 39 denotes time information adding means for recognizing and adding time information (TS) at which an output signal of the ECC encoder 12 is output for each predetermined information unit (hereinafter referred to as a block). Time information is added to each block of the output signal and output to the buffer 29. Reference numeral 29 denotes a buffer provided between the ECC encoder 12 and the synchronizing signal adding means 13 for temporarily storing the output signal of the ECC encoder 12, and the buffer 29 stores the output signal of the ECC encoder 12 and keeps the output signal within a predetermined time. Is output to the synchronization signal adding means 13 as one set unit. In this embodiment, the fixed time is one line cycle. Note that the buffer 29 may be configured so that when a certain amount of information corresponding to one set information unit is accumulated, the set information unit is collected and output to the synchronization signal adding unit 13.
[0084]
On the other hand, when the ECC encoder 12 is not used, the time information adding unit 39 is configured to recognize the time information (TS) at which the output signal of the compression unit 4 is output for each block. Is added to the time information and output to the buffer 29. The buffer 29 may be provided between the compression means 4 and the synchronization signal adding means 13 to temporarily store the output signal of the compression means 4.
[0085]
Reference numeral 40 denotes time information reproducing means for recognizing the time information added by the time information adding means 39 for each block. The buffer 31 storing the output signal of the synchronizing signal removing unit 7 in accordance with the instruction of the time information reproducing unit 40 outputs the stored information signal to the ECC decoder 14 at a timing corresponding to the time information for each block. Reference numeral 31 denotes a buffer provided between the synchronization signal removing unit 7 and the ECC decoder 14 for temporarily storing the output signal of the synchronization signal removing unit 7.
[0086]
On the other hand, when the ECC decoder 14 is not used, the time information reproducing means 40 recognizes the time information added by the time information adding means 39 for each block. The buffer 31 storing the output signal of the synchronizing signal removing unit 7 in accordance with the instruction of the time information reproducing unit 40 outputs the stored information signal at a timing corresponding to the time information for each block. The buffer 31 may be provided between the synchronizing signal removing means 7 and the decompressing means 11 to temporarily store the output signal of the synchronizing signal removing means 7.
[0087]
That is, in the transmitting apparatus or the transmitting method, the compression unit 4 (when the ECC encoder 12 is not used) or the ECC encoder 12 (when the ECC encoder 12 is used in the first embodiment or the second embodiment described above) ), The information indicating the time at which the output signal was output is recognized for each block, and time information is added to the output signal of the compression means 4 (when the ECC encoder 12 is not used) or the output signal of the ECC encoder 12 (when the ECC encoder 12 is used). Is added for each block. The most characteristic feature is that the information signal is output from the compression means 4 (when the ECC encoder 12 is not used) or the ECC encoder 12 (when the ECC encoder 12 is used) for each block. That is, the time information is added.
[0088]
On the other hand, in the receiving apparatus or the receiving method, the output signal of the synchronizing signal removing means 7 is delayed for each block based on the time information in (Embodiment 1) or (Embodiment 2) described above, and the synchronizing signal is The information representing the time included in the output signal of the removing means 7 is recognized for each block. The most characteristic feature is that the output signal of the synchronizing signal removing means 7 is based on the time information added for each block. Is output with a delay for each block.
[0089]
Such a transmission device or transmission method and a reception device or reception method constitute a transmission system or transmission method via a transmission path.
[0090]
The operation of the above-described transmission system or transmission method will be described below.
[0091]
In the transmitting apparatus or the transmitting method, the digital video input signal is input to the compression means 4 to compress the amount of information, and is output after being blocked into a certain information unit. The output signal of the compression means 4 (see FIG. 13A) is output to the ECC encoder 12. In the output signal of the compression means 4, an error correction code is added to each of the information signals 1 to 3 in the ECC encoder 12. Next, the output signal of the ECC encoder 12 (see FIG. 13B) is added by the time information adding means 39 at that time, that is, the time information (TS) at which the output signal of the ECC encoder 12 is output is added for each block ( (FIG. 13C) The data is input to the buffer 29. Here, time information 1 (TS1) to time information 3 (TS3) are added to each of the information signals 1 to 3.
[0092]
The output signal of the ECC encoder 12 is stored in the buffer 29, and is output to the synchronization signal adding unit 13 with the information stored within a fixed time (corresponding to one line cycle in this embodiment) as one set unit. (FIG. 13D). The output signal of the buffer 29 is output to the synchronizing signal adding means 13 and is transmitted via the transmission line after the synchronizing signal is added.
[0093]
On the other hand, in the receiving apparatus or the receiving method, after the synchronization signal is removed by the synchronization signal removing means 7 from the received signal, the output signal (FIG. 13E) of the synchronization signal removing means 7 is the time in the output signal. Based on the information 1 (TS1) to the time information 3 (TS3), the information signals 1 to 3 are delayed by the buffer 31 at the time of transmission so that each block has the same time interval as that output from the ECC encoder 12. Is output. The output signal (FIG. 13 (f)) of the buffer 31 is input to the ECC decoder 14, where the signal is corrected based on the error correction code. The output signal (FIG. 13 (g)) of the ECC decoder 14 is expanded by the expansion means 11 to become a digital video output signal.
[0094]
By adopting such a configuration, the time interval in the time information adding means 28 can be included in one set information unit while the time information is reproduced from the information sent in a burst manner on the receiving side, so that signal transmission can be efficiently performed. Can do well.
[0095]
In addition, since the time information is transmitted without being compressed, it can be used immediately after receiving without decompression operation.
[0096]
In the present embodiment, the time information adding means 28 is provided in (Embodiment 1) or (Embodiment 2), but the same applies to the case where the time information adding means is provided in other embodiments. The effect is obtained.
[0097]
(Embodiment 7)
FIG. 14 is a diagram showing a transmission system or a transmission method according to a seventh embodiment of the present invention, and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system or the transmission method. Is added for each fixed information unit (hereinafter, referred to as a block). Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0098]
In particular, the present embodiment (FIGS. 14 and 15) provides a more detailed embodiment of the time information adding means 28, the time information reproducing means 30, and the time information adding / reproducing method of (Embodiment 5). Is what you do.
[0099]
The time information adding unit 28 includes a predetermined unit counting unit 50a and a predetermined unit counting unit 51a. Here, the information signal handled by the transmission device or the reception device of the present invention according to the present embodiment is a video signal, and a plurality of pieces form a predetermined unit.
[0100]
The predetermined unit counting means 50a counts the number of line cycles, counts the number of line cycles of a block input to the ECC encoder 12 from a predetermined reference, and counts the value. Output with N bits. Here, the predetermined criterion is a time criterion, and may have a configuration in which a clock is commonly used between transmission and reception, and may be based on a specific time, a block previously transmitted from the transmission side to the reception side, or the like. A specific signal such as a synchronization signal may be used as a reference.
[0101]
When the predetermined unit counting unit 50a counts a frame, the predetermined unit counting unit 50a can count the frame based on the head of the frame or the rising or falling of the vertical synchronization signal. When the predetermined unit counting unit 50a counts a field, the predetermined unit counting unit 50a can count the field based on the head of the field or the rising or falling of the vertical synchronization signal. Further, when the predetermined unit counting unit 50a counts the lines, the predetermined unit counting unit 50 can count the lines based on the head of the line or the rising or falling of the horizontal synchronization signal. That is, it is only necessary that a common time period between transmission and reception and a certain time period can be counted.
[0102]
Here, a frame is a period during which an image is formed on one screen, and a period during which two vertical scans are performed in the NTSC system. A field is a period during which one vertical scan is performed in a television signal. Means a period for one horizontal scan.
[0103]
The predetermined unit counting means 51a counts the time from the position (timing) serving as the reference of the line cycle to the present, that is, the timing when the block of the video signal is input to the encoder 12, and uses the counted value as time information. It is output in M bits.
[0104]
When the predetermined unit counting unit 50a counts a frame, the predetermined unit counting unit 51a sets the head (starting or falling) position (timing) of the frame or the vertical synchronization signal as a fixed position (timing). The time from the fixed position (timing) to the present time, that is, the position (timing) at which the block of the video signal is input to the encoder 12 can be counted. When the predetermined unit counting means 50a counts a field, the predetermined unit counting means 51a sets the head (heading) of the field or the rising or falling position (timing) of the vertical synchronization signal as a fixed position (timing). The time from the fixed position (timing) to the present time, that is, the position (timing) at which the block of the video signal is input to the encoder 12 can be counted. Further, when the predetermined unit counting means 50a counts the lines, the predetermined unit counting means 51a sets the head (heading) of the line or the rising or falling position (timing) of the horizontal synchronization signal as a fixed position (timing). The time from the fixed position (timing) to the present time, that is, the position (timing) at which the block of the video signal is input to the encoder 12 can be counted.
[0105]
Therefore, as a whole, the time information adding means 28 sets the N-bit signal output from the predetermined unit counting means 50a as the high order and the M-bit signal output from the predetermined unit counting means 51a as the low order, so that the total (N + M) bits Information is added to the input signal of the ECC encoder 12.
[0106]
On the other hand, when the ECC encoder 12 is not used, the time information adding unit 28 is configured to recognize and add the time information (TS) to which the output signal of the compression unit 4 is output for each block. , And adds time information for each block, and outputs the result to the buffer 29a. The buffer 29a is provided between the compression means 4 and the synchronization signal addition means 13, temporarily stores the output signal of the compression means 4, and outputs the information accumulated within a certain time to the synchronization signal addition means 13 as one set unit. The configuration may be such that
[0107]
Next, the time information reproducing means 30 is constituted by a predetermined unit delay means 52a and a predetermined unit delay means 53a. The predetermined unit delay unit 52a receives the N-bit predetermined unit time information supplied by the predetermined unit counting unit 50a (when the block of the video signal input to the ECC encoder 12 is at what line period from a predetermined reference, Recognition).
[0108]
The predetermined intra-unit delay means 53a outputs the M-bit predetermined intra-unit time information supplied from the predetermined intra-unit counting means 51a (the position of the line period as a reference, for example, from the head position (timing) of the line) to the ECC encoder. 12 (information indicating a time until a position (timing) is input).
[0109]
The buffer 31a in which the output signal of the ECC decoder 14 is stored is stored in the predetermined unit delay unit 53a based on the time timing corresponding to the time information represented by the predetermined unit time information recognized by the predetermined unit delay unit 52a. For each time corresponding to the time information represented by the time information within the predetermined unit recognized by the above, the stored video signal is delayed and output for each block.
[0110]
On the other hand, when the ECC decoder 14 is not used, the time information reproducing means 30 recognizes the time information added by the time information adding means 28 for each block. The buffer 31a in which the output signal of the synchronizing signal removing means 7 is stored according to the instruction of the time information reproducing means 30 outputs the stored information signal at a timing corresponding to the time information for each block. The buffer 31a may be provided between the synchronizing signal removing means 7 and the decompressing means 11, and may temporarily store the output signal of the synchronizing signal removing means 7.
[0111]
That is, the transmission device or the transmission method of the present invention is the case where the line cycle of the video signal is a predetermined unit, the number of blocks that are constant information units of the video signal that is an information signal occurs in the line cycle, That is, when a plurality of lines form a predetermined unit, the time information described in (Embodiment 5) uses the information signal (video signal output from the compression unit 4 (when the ECC encoder 12 is not used)). ) Or when the information signal (video signal) input to the ECC encoder 12 (when the ECC encoder 12 is used) is a predetermined unit (line cycle) from a predetermined reference, the output from the compression means 4 or the ECC encoder 12 and a fixed unit time information indicating whether the information signal has been input to the unit 12 and its information signal (video signal) being a reference of a predetermined unit (line cycle). And time information from the head position (timing) of the line, which is the position (timing), to the present time, that is, the time from the compression means 4 to the position (timing) output or input to the ECC encoder 12. I have.
[0112]
On the other hand, when the receiving apparatus or the receiving method of the present invention uses a line cycle of a video signal as a predetermined unit, the number of blocks that are constant information units of the video signal that is an information signal occurs in the line cycle, In the case where a unit is collected to form a predetermined unit, the time information described in (Embodiment 5) is an information signal (video signal) or an ECC encoder output from the compression unit 4 (when the ECC encoder 12 is not used). 12 (when the ECC encoder 12 is used), the information signal (video signal) is output from the compression means 4 or input to the ECC encoder 12 at what number of predetermined units (line periods) from a predetermined reference. And a fixed position (time) at which the information signal (video signal) becomes a reference of a predetermined unit (line cycle). And a predetermined unit of time information representing the time from the head position (timing) of the line, which is the current position, that is, the position (timing) output from the compression means 4 or input to the ECC encoder 12 (timing). Based on the time information added to each information signal (video signal) of the information unit (block) of the information unit (block), output from the compression unit 4 (when the ECC encoder 12 is not used) A timing corresponding to a time corresponding to information indicating the number of a line cycle of a video signal block input to the encoder 12 (when the ECC encoder 12 is used) from a predetermined reference) In addition, as a configuration for delaying a constant time information unit (block) represented by time information within a predetermined unit from the timing, That.
[0113]
The operation of the above transmission system will be described with reference to FIG.
[0114]
FIG. 15 is a diagram illustrating operations of the transmission side and the reception side in one set information unit of the transmission system or the transmission method according to the seventh embodiment of the present invention.
[0115]
In the transmission device or the transmission method, the digital video input signal is input to the compression means 4 and the amount of information is compressed. The output signal of the compression means 4 (FIG. 15 (a)) is output to the ECC encoder 12, and the predetermined unit counting means 50a and the predetermined unit counting means 51a, which are the time information adding means 28, are input to the ECC encoder 12 at that time. The time information (TS) to which the signal is input is added for each block (FIG. 15B). Here, the time information output by the time information adding means 28 is an N-bit signal output from the predetermined unit counting means 50a (in FIG. 15, N is described as a line number: 2, 3,...). An M-bit signal (M is shown as T1, T2,... In FIG. 15) output from the predetermined unit counting means 51a is configured as a lower bit. The N-bit signal output from the predetermined unit counting means 50a is predetermined unit time information indicating the number of a line indicating the number of a line cycle of the block from a predetermined reference and input to the ECC encoder 12. The M-bit signal output from the predetermined unit counting means 51a is output from the head of a line at a fixed position (timing) serving as a reference of a line cycle to which the block input to the ECC encoder 12 belongs, Is time information in a predetermined unit indicating a time until a position (timing) of the video signal input to the ECC encoder 12. In this case, each of the video signals has time information (TS21 to TS33, where TSnm is a natural number of 1 or more for both n and m, and n is input to the ECC encoder 12 when the block period of what number of blocks is reached. Represents the line number (corresponding to the predetermined unit time information) indicating the length of the line, and m is a fixed position (timing) which is a reference of a line cycle to which the block input to the ECC encoder 12 belongs, from the beginning of the line. Represents the time until the position (timing) of the video signal whose block is currently input to the ECC encoder 12, and represents the number of the in-line time (corresponding to the number of the information in the predetermined unit). ) Is added. Next, the ECC encoder 12 attaches an error correction code to each video signal and time information (TS21 to TS33).
[0116]
The output signal of the ECC encoder 12 (see FIG. 15C) is temporarily stored in the buffer 29a, and is output to the synchronization signal adding means 13 using the information stored within the fixed time as one set unit. The output signal of the buffer 29a is output to the synchronization signal adding means 13 and is transmitted via the transmission path after the synchronization signal is added (FIG. 15D).
[0117]
On the other hand, in the receiving apparatus or the receiving method, after the synchronization signal is removed by the synchronization signal removing unit 7 from the received signal (FIG. 15E), the output signal (FIG. 15F) of the synchronization signal removing unit 7 becomes The ECC decoder 14 performs signal error correction based on the error correction code. Next, based on the time information (TS21 to TS33) in the output signal (FIG. 15 (g)) of the ECC decoder 14, the block of the video signal is set for each block at the same time interval as when the video signal was input at the time of transmission. The data is output after being delayed by the buffer 31a (FIG. 15 (h)). That is, the predetermined unit delay means 52a recognizes the line number which is the predetermined unit time information (N bits) added by the predetermined unit counting means 50a, and the predetermined unit delay means 53a is supplied by the predetermined unit counting means 51a. Recognized M-bit time information (information within a predetermined unit from the head of the line to the position (timing) at which the video signal block is input to the ECC encoder 12). The block of the video signal stored in the buffer 31a in accordance with the instructions of the predetermined unit delay unit 52a and the predetermined unit delay unit 53a has N bits of predetermined unit time information (to what order from a predetermined reference the line belongs. Based on the timing corresponding to the time information (T1 to T5) (the fixed position (timing) of the line to which the block of the video signal belongs) (the beginning of the video signal) , A time information unit (block) corresponding to a time (time information indicating the time from the current input signal to the position (timing) of the video signal) is output with a delay. Thereafter, the output signal of the buffer 31a is expanded to become a digital video output signal.
[0118]
With this configuration, the same effect as that of the fifth embodiment can be obtained.
[0119]
In the present embodiment, the time information adding means 28 is provided in (Embodiment 2), but the same effect can be obtained by providing the time information adding means in other embodiments.
[0120]
Here, in the present embodiment, a video signal is used as the information signal, and a predetermined unit of the video signal is one line of the video signal. However, a signal other than the video signal may be used, and the predetermined unit may be a constant interval. Therefore, the predetermined unit may be n frames (n is a natural number of 1 or more) of the video signal, or the predetermined unit may be n fields and n lines of the video signal (n is a natural number of 1 or more).
[0121]
Further, in the present embodiment, one set information unit is constituted by blocks which are constant information units generated within one line period, but one set information unit is composed of n lines (n is 1 or more) of a video signal. Can be constituted by a block, which is a constant information unit generated within a period of (a natural number) of a video signal, and one set of information units is generated within a period of n fields and n frames (n is a natural number of 1 or more) of a video signal. It may be constituted by a block which is a fixed information unit.
[0122]
Further, the fixed position (timing) serving as a reference of a predetermined unit of the video signal may be any position as long as it is synchronized with any one of the line, field, and frame periods. Therefore, it does not necessarily have to be the head of any of the line, field, and frame. For example, the same can be applied to the rising or falling part of the vertical synchronizing signal or the horizontal synchronizing signal, as long as it is a fixed position (timing) (timing) of a fixed cycle.
[0123]
Further, when the predetermined unit is one line, a line counter can be used as a predetermined unit counting means, and when it is one field, a field counter can be used as a predetermined unit. Because it is possible, the cost of the apparatus can be reduced.
[0124]
Also, as shown in FIG. 18, a predetermined identification number for each predetermined unit (in the present embodiment, a line number assigned to each line, and in FIG. 18, identification numbers 1... Identification number n (N is a natural number of 1 or more, where 1 to n correspond to the line number) in the synchronization signal or together with the synchronization signal to transmit the information, the predetermined unit counting means 50a and the predetermined unit counting means 50a in the present embodiment. The unit delay unit 52a can be dispensed with.
[0125]
That is, on the transmitting side, when a plurality of certain information units of the information signal are collected to form a predetermined unit and the predetermined unit has an identification code for identifying each predetermined unit, the time information adding means A predetermined unit counting means for counting a time from a fixed position (timing) serving as a reference of a predetermined unit of the information signal to a position (timing) to which time information (TS) is added; The feature is that time information within a predetermined unit indicating a time from a fixed position (timing) where the time information (TS) is a reference of a predetermined unit of the information signal to a position (timing) where the time information (TS) is added. It is composed of
[0126]
On the other hand, on the receiving side, when a plurality of certain information units of the information signal are collected to form a predetermined unit and the predetermined unit has an identification code for identifying each predetermined unit, the predetermined unit of the information signal is Of the predetermined unit representing the time from the fixed position (timing) as a reference to the position (timing) to which the time information (TS) is added, and is added for each information signal of this fixed information unit. According to the time information set, a constant time information unit (block) represented by the time information within the predetermined unit of the information signal is delayed for each information signal of the predetermined information unit. Time in a predetermined unit indicating a time from a fixed position (timing) where information (TS) is a reference of a predetermined unit of the information signal to a position (timing) to which time information (TS) is added Time information unit (block) represented by time information within a predetermined unit of the information signal for each information signal of the certain information unit in accordance with the time information added to each information signal of the certain information unit. ) Is delayed.
[0127]
When one set of information units is assumed to be information accumulated within a certain period of time, for example, the number of blocks generated as a certain information unit within one line cycle of a video signal is collected to form one set of information units. In this case, the predetermined unit counting unit 50a and the predetermined unit delay unit 52a in the present embodiment can be omitted.
[0128]
In other words, on the transmitting side, when a plurality of certain information units of the information signal are collected to form a predetermined unit having a certain time length, the time information adding means sets the fixed unit serving as a reference of the predetermined unit of the information signal. A predetermined unit counting means counts the time from the position (timing) to the position (timing) to which the time information (TS) is added. This is configured from time information within a predetermined unit representing a time from a fixed position (timing) serving as a reference of a predetermined unit to a position (timing) to which time information (TS) is added.
[0129]
On the other hand, on the receiving side, when a plurality of certain information units of the information signal are collected to form a predetermined unit having a certain time length, the information unit is obtained by counting the number of the certain information signal or the predetermined unit. This fixed information unit is constituted by time information in a predetermined unit indicating a time from a fixed position (timing) serving as a reference of a predetermined unit of the information signal to a position (timing) to which the time information (TS) is added. In accordance with the time information added to each of the information signals, a constant time information unit (block) represented by the time information in the predetermined unit of the information signal is delayed for each information signal of the predetermined information unit. The feature is that when the time information (TS) is from a fixed position (timing) as a reference of a predetermined unit of the information signal to a position (timing) where the time information (TS) is added. The time represented by the predetermined unit time information of the information signal for each information signal of the certain information unit according to the time information added to each information signal of the certain information unit. It is configured to delay a certain information unit (block).
[0130]
Further, in the present embodiment, the same buffer 31a is used, and the buffer 31a simultaneously delays a block of the video signal by a time corresponding to (predetermined unit information + information in a predetermined unit). After delaying an information unit (block) having a fixed time corresponding to the predetermined time, an information unit (block) having a fixed time corresponding to the information in the predetermined unit may be delayed, or a constant time corresponding to the information in the predetermined unit may be delayed. After the information unit (block) is delayed, a constant time information unit (block) corresponding to the predetermined unit information may be delayed.
[0131]
(Embodiment 8)
FIG. 16 is a diagram showing a transmission system or a transmission method according to an eighth embodiment of the present invention and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system or the transmission method. In the case of adding the time information of the output signal output from each block. Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0132]
In particular, the present embodiment (FIGS. 16 and 17) is another embodiment in which the time information adding means 39, the time information reproducing means 40, and the time information adding / reproducing method of (Embodiment 6) are further detailed. Is provided.
[0133]
The time information adding unit 39 includes a predetermined unit counting unit 50b and a predetermined unit counting unit 51b. Here, the information signal handled by the transmitting device or the receiving device of the present invention according to the present embodiment is a video signal, and a plurality of certain information units are collected to form a predetermined unit.
[0134]
The predetermined unit counting means 50b counts the number of line cycles, counts the number of line cycles at which a block output from the ECC encoder 12 is output from a predetermined reference, and determines the value. Output with N bits. Here, the predetermined criterion is a criterion of time, and may be configured to have a common clock between transmission and reception and may be based on a specific time, or may be a block previously transmitted from the transmission side to the reception side. Or a specific signal such as a synchronization signal.
[0135]
When the predetermined unit counting unit 50b counts a frame, the predetermined unit counting unit 50b can count the frame based on the start of the frame or the rising or falling of the vertical synchronization signal. When the predetermined unit counting unit 50b counts a field, the predetermined unit counting unit 50b can count the field based on the head of the field or the rising or falling of the vertical synchronization signal. Further, when the predetermined unit counting unit 50b counts a line, the predetermined unit counting unit 50 can count the line based on the head of the line or the rising or falling of the horizontal synchronization signal. That is, it is only necessary that a common time period between transmission and reception and a certain time period can be counted.
[0136]
Here, a frame is a period during which an image is formed on one screen, and a period during which two vertical scans are performed in the NTSC system. A field is a period during which one vertical scan is performed in a television signal. Means a period for one horizontal scan.
[0137]
The predetermined unit counting means 51b counts a time from a position (timing) serving as a reference of a line cycle to a present time, that is, a timing at which a block of a video signal is output from the encoder 12, and the counted value is represented by time information. As M bits.
[0138]
When the predetermined unit counting unit 50b counts a frame, the predetermined unit counting unit 51b sets the beginning (starting or falling) position (timing) of the frame or the vertical synchronization signal as a fixed position (timing). The time from the fixed position (timing) to the present, that is, the position (timing) at which the block of the video signal is output from the encoder 12 can be counted. When the predetermined unit counting unit 50b counts a field, the predetermined unit counting unit 51b sets the start (starting) or falling (falling) position (timing) of the field or the vertical synchronization signal as a fixed position (timing). The time from the fixed position (timing) to the present time, that is, the position (timing) at which the block of the video signal is input to the encoder 12 can be counted. Further, when the predetermined unit counting means 50b counts a line, the in-predetermined-unit counting means 51b sets the head (starting) or the rising (falling) position (timing) of the line or the horizontal synchronization signal as a fixed position (timing). The time from the fixed position (timing) to the present, that is, the position (timing) at which the block of the video signal is output from the encoder 12 can be counted.
[0139]
Therefore, as a whole, the time information adding means 39 sets the N-bit signal output from the predetermined unit counting means 50b as the high order, and sets the M-bit signal output from the predetermined unit counting means 51b as the low order, so that the total (N + M) bits Information is added to the output signal of the ECC encoder 12.
[0140]
On the other hand, when the ECC encoder 12 is not used, the time information adding means 39 is configured to recognize and add, for each block, the time information (TS) to which the output signal of the compression means 4 is output. Is added to the time information for each block and output to the buffer 29b. The buffer 29b is provided between the compression means 4 and the synchronization signal addition means 13, temporarily stores the output signal of the compression means 4, and outputs the stored information to the synchronization signal addition means 13 as one aggregate information unit. And it is sufficient.
[0141]
Next, the time information reproducing means 30 is constituted by a predetermined unit delay means 52b and a predetermined unit delay means 53b. The predetermined unit delay unit 52b receives the N-bit predetermined unit time information supplied by the predetermined unit counting unit 50b (when the block of the video signal output from the ECC encoder 12 is at what line cycle from a predetermined reference, Recognition).
[0142]
The predetermined intra-unit delay means 53b outputs the M-bit predetermined intra-unit time information supplied from the predetermined intra-unit counting means 51b (from the reference position of the line cycle, for example, from the position (timing) at the head of the line, that is, Recognize the time until the block is output from the ECC encoder 12 (timing).
[0143]
The buffer 31b in which the output signal of the synchronizing signal removing means 7 has been stored is based on a time timing corresponding to the time information represented by the predetermined unit time information recognized by the predetermined unit delay means 52b, and is further delayed from the timing by a predetermined intra-unit delay. The accumulated video signal is output with a delay for each block corresponding to the time information represented by the time information in the predetermined unit recognized by the means 53b.
[0144]
On the other hand, when the ECC decoder 14 is not used, the time information reproducing means 40 recognizes the time information added by the time information adding means 39 for each block. The buffer 31b in which the output signal of the synchronizing signal removing means 7 is stored in accordance with the instruction of the time information reproducing means 40 outputs the stored information signal at a timing corresponding to the time information for each block. The buffer 31b may be provided between the synchronizing signal removing means 7 and the decompressing means 11 and may temporarily store the output signal of the synchronizing signal removing means 7.
[0145]
In other words, the transmission device or the transmission method of the present invention uses the line cycle of a video signal as a predetermined unit, and a block that is a constant information unit of the video signal as an information signal is included in one line cycle of the video signal. In the case where a predetermined unit is formed by gathering a plurality of pieces of information, the time information described in (Embodiment 6) uses the compression means 4 (when the ECC encoder 12 is not used) or the ECC encoder 12 (the ECC encoder 12). Is a predetermined unit time indicating the number of a predetermined unit (line cycle) of the information signal (video signal) output from the compression unit 4 or the ECC encoder 12 from a predetermined reference. Information and the top position of a line where the information signal (video signal) is a fixed position (timing) serving as a reference for a predetermined unit (line cycle) Is constituted by the current from the (timing), that is, within a predetermined unit representing a time until position information signal output from the compressing means 4 or the ECC encoder 12 (video signal) (timing) time information.
[0146]
On the other hand, the receiving apparatus or the receiving method of the present invention uses the line cycle of a video signal as a predetermined unit, and a block that is a constant information unit of the video signal as an information signal is included in one line cycle of the video signal. In the case where a predetermined unit is formed by gathering a plurality of pieces of information, the time information described in (Embodiment 6) uses the compression means 4 (when the ECC encoder 12 is not used) or the ECC encoder 12 (the ECC encoder 12). A predetermined unit time indicating the number of a predetermined unit (line cycle) of the information signal (video signal) output from the compression unit 4 or the ECC encoder 12 from a predetermined reference. Information and the head position (line) of the line where the information signal (video signal) is a fixed position (timing) serving as a reference for a predetermined unit (line cycle) ) To the current time, that is, the time information from the compression means 4 or the position (timing) output from the ECC encoder 12 within a predetermined unit, and an information signal (video) of this fixed information unit (block). Video output from the time represented by the predetermined unit time information (compressor 4 (when not using ECC encoder 12) or ECC encoder 12 (when using ECC encoder 12)) based on the time information added for each signal) The time corresponding to the information indicating the number of the line cycle of the signal block output from the predetermined reference) is used as a reference, and the time represented by the time information within the predetermined unit from the timing is constant. The information unit (block) is configured to be delayed.
[0147]
The operation of the above transmission system will be described with reference to FIG.
[0148]
FIG. 17 is a diagram illustrating operations of the transmission side and the reception side in one set of information units of the transmission system or the transmission method according to the eighth embodiment of the present invention.
[0149]
In the transmission device or the transmission method, the digital video input signal is input to the compression means 4 and the amount of information is compressed. The output signal (FIG. 17 (a)) of the compression means 4 is output to the ECC encoder 12, and the ECC encoder 12 applies an error correction code to each video signal. Next, the predetermined unit counting means 50b and the predetermined unit counting means 51b, which are the time information adding means 39, output the time information (TS) at which the output signal (see FIG. 17B) from the ECC encoder 12 was output. ) Is added for each block (FIG. 17C).
[0150]
Here, the time information output by the time information adding means 39 is based on an N-bit signal output from the predetermined unit counting means 50b (in FIG. 17, N is described as a line number: 2, 3,...) As upper bits. An M-bit signal (M is described as T1, T2,... In FIG. 17) output from the predetermined unit counting means 51b is configured as a lower bit.
[0151]
The N-bit signal output from the predetermined unit counting means 50b is predetermined unit time information indicating a line number indicating the number of a line cycle of the block from the ECC encoder 12 from a predetermined reference. The M-bit signal output from the predetermined unit counting means 51b is output from the head of a line at a fixed position (timing) serving as a reference of a line cycle to which the block output from the ECC encoder 12 belongs, from the head of the block. Is time information in a predetermined unit indicating the time until the position (timing) of the video signal output from the ECC encoder 12. In this case, each of the video signals has time information (TS21 to TS33, where TSnm is a natural number of 1 or more for both n and m, and n is output from the ECC encoder 12 at what line cycle of the block. Represents a line number (corresponding to predetermined unit time information) indicating the number of lines, and m is a fixed position (timing) which is a reference of a line cycle to which a block output from the ECC encoder 12 belongs, from the beginning of the line. Represents the time until the position (timing) of the video signal whose block is currently output from the ECC encoder 12, and represents the number of the in-line time (corresponding to the number of the information in the predetermined unit). ) Is added.
[0152]
The output signal of the ECC encoder 12 is temporarily stored in the buffer 29b, and is output to the synchronization signal adding unit 13 using the information stored within a certain time as one set unit.
[0153]
The output signal of the buffer 29b is output to the synchronization signal adding means 13 and is transmitted via the transmission path after the synchronization signal is added (FIG. 17D).
[0154]
On the other hand, in the receiving device or the receiving method, after the synchronization signal is removed by the synchronization signal removing unit 7 in the received signal (FIG. 17E), the output signal of the synchronization signal removing unit 7 (FIG. 17F) becomes On the basis of the time information (TS21 to TS33) in the output signal of the synchronization signal removing means 7, the block of the video signal is delayed by the buffer 31b so as to have the same time interval as the video signal was input at the time of transmission for each block. Further output is performed (FIG. 17 (g)). Thereafter, the ECC decoder 14 performs error correction of the signal based on the error correction code (FIG. 17 (h)). That is, the predetermined unit delay unit 52b recognizes the line number which is the predetermined unit time information (N bits) added by the predetermined unit counting unit 50b, and the predetermined unit delay unit 53b is supplied by the predetermined unit counting unit 51b. Recognized M-bit time information (information in a predetermined unit from the head of the line to the current block, ie, the block at the position (timing) where the video signal is output from the ECC encoder 12). The block of the video signal stored in the buffer 31b in accordance with the instructions of the predetermined unit delay means 52b and the predetermined unit delay means 53b has N bits of predetermined unit time information (to what number line from a predetermined reference belongs. Based on the timing corresponding to the time information (time information representing the time), the time information within the predetermined unit (T1 to T5) (the fixed position (timing) of the line to which the block of the video signal belongs) (the beginning of the video signal) , A time information unit (block) corresponding to a time (time information indicating the time from the current input signal to the position (timing) of the video signal) is output with a delay. Thereafter, the output signal of the buffer 31b is subjected to error correction of the signal by the ECC decoder 14 based on the error correction code, and is further expanded to a digital video output signal.
[0155]
With this configuration, the same effect as that of the sixth embodiment can be obtained.
[0156]
In the present embodiment, the time information adding means 28 is provided in (Embodiment 2), but the same effect can be obtained by providing the time information adding means in other embodiments.
[0157]
Here, in the present embodiment, a video signal is used as the information signal, and a predetermined unit of the video signal is one line of the video signal. However, a signal other than the video signal may be used, and the predetermined unit may be a constant interval. Therefore, the predetermined unit may be n frames (n is a natural number of 1 or more) of the video signal, or the predetermined unit may be n fields and n lines of the video signal (n is a natural number of 1 or more).
[0158]
Further, in the present embodiment, one set information unit is constituted by blocks which are constant information units generated within one line period, but the set information unit is defined as n lines (n is a natural number of 1 or more) of a video signal. ) It can be composed of blocks which are constant information units generated within a period, and a set information unit is a fixed information unit generated within a period of n fields of an image signal and n frames (n is a natural number of 1 or more). May be constituted by the following block.
[0159]
The fixed position (timing) of the predetermined unit of the video signal may be any position as long as it is synchronized with any one of the line, field, and frame periods.
[0160]
Therefore, it does not necessarily have to be the head of any of the line, field, and frame. For example, the same can be applied to the rising or falling portion of the vertical synchronizing signal or the horizontal synchronizing signal, as long as it is a fixed position (timing) having a fixed cycle.
[0161]
Further, when the predetermined unit is one line, a line counter can be used as a predetermined unit counting means, and when it is one field, a field counter can be used as a predetermined unit. Because it is possible, the cost of the apparatus can be reduced.
[0162]
Also, as shown in FIG. 18, a predetermined identification number for each predetermined unit (in the present embodiment, a line number assigned to each line, and in FIG. 18, identification numbers 1... Identification number n (N is a natural number of 1 or more, where 1 to n correspond to the line number) in the synchronization signal or together with the synchronization signal to transmit information, the predetermined unit counting means 50b and the predetermined unit counting means 50b in the present embodiment. The unit delay means 52b can be dispensed with.
[0163]
That is, on the transmitting side, when a plurality of certain information units of the information signal are collected to form a predetermined unit and the predetermined unit has an identification code for identifying each predetermined unit, the time information adding means A predetermined unit counting means for counting a time from a fixed position (timing) serving as a reference of a predetermined unit of the information signal to a position (timing) to which time information (TS) is added; The feature is that time information within a predetermined unit indicating a time from a fixed position (timing) where the time information (TS) is a reference of a predetermined unit of the information signal to a position (timing) where the time information (TS) is added. It is composed of
[0164]
On the other hand, on the receiving side, when a plurality of certain information units of the information signal are collected to form a predetermined unit and the predetermined unit has an identification code for identifying each predetermined unit, the predetermined unit of the information signal is Of the predetermined unit representing the time from the fixed position (timing) as a reference to the position (timing) to which the time information (TS) is added, and is added for each information signal of this fixed information unit. According to the time information set, a constant time information unit (block) represented by the time information within the predetermined unit of the information signal is delayed for each information signal of the predetermined information unit. Time in a predetermined unit indicating a time from a fixed position (timing) where information (TS) is a reference of a predetermined unit of the information signal to a position (timing) to which time information (TS) is added Time information unit (block) represented by time information within a predetermined unit of the information signal for each information signal of the certain information unit in accordance with the time information added to each information signal of the certain information unit. ) Is delayed.
[0165]
When one set of information units is assumed to be information accumulated within a certain period of time, for example, the number of blocks generated as a certain information unit within one line period of a video signal is collected to form one set of information units. In this case, the predetermined unit counting unit 50a and the predetermined unit delay unit 52a in the present embodiment can be omitted.
[0166]
In other words, on the transmitting side, when a plurality of certain information units of the information signal are collected to form a predetermined unit having a certain time length, the time information adding means sets the fixed unit serving as a reference of the predetermined unit of the information signal. A predetermined unit counting means counts the time from the position (timing) to the position (timing) to which the time information (TS) is added. This is configured from time information within a predetermined unit representing a time from a fixed position (timing) serving as a reference of a predetermined unit to a position (timing) to which time information (TS) is added.
[0167]
On the other hand, on the receiving side, when a plurality of certain information units of the information signal are gathered to form a predetermined unit having a certain time length, the information unit is obtained by counting the number of the certain information signal or the predetermined unit. This fixed information unit is constituted by time information in a predetermined unit indicating a time from a fixed position (timing) serving as a reference of a predetermined unit of the information signal to a position (timing) to which the time information (TS) is added. In accordance with the time information added to each of the information signals, a constant time information unit (block) represented by the time information in the predetermined unit of the information signal is delayed for each information signal of the predetermined information unit. The feature is that when the time information (TS) is from a fixed position (timing) as a reference of a predetermined unit of the information signal to a position (timing) where the time information (TS) is added. The time represented by the predetermined unit time information of the information signal for each information signal of the certain information unit according to the time information added to each information signal of the certain information unit. It is configured to delay a certain information unit (block).
[0168]
Further, in the present embodiment, the same buffer 31b is used, and the buffer 31b simultaneously delays a block of the video signal by a time corresponding to (predetermined unit information + information in a predetermined unit). After delaying an information unit (block) having a fixed time corresponding to the predetermined time, an information unit (block) having a fixed time corresponding to the information within the predetermined unit may be delayed, or a fixed time unit corresponding to the information within the predetermined unit may be delayed. After the information unit (block) is delayed, a constant time information unit (block) corresponding to the predetermined unit information may be delayed.
[0169]
(Embodiment 9)
FIG. 19 is a diagram showing a transmission system or a transmission method according to a ninth embodiment of the present invention and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system (the ECC encoder 12 in the time information adding means 28). In the case where the time information when the signal is input to the block is added for each block). Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0170]
The present embodiment provides another embodiment that is more detailed with respect to the time information adding unit 28, the time information reproducing unit 30, and the method of adding and reproducing the time information, in particular (Embodiment 5). is there.
[0171]
The time information adding means 28 includes an N-bit counter 54a as the predetermined unit counting means 50a and an M-bit counter 55a as the predetermined unit counting means 51a.
[0172]
Here, the information signal handled by the transmitting device or the receiving device of the present invention according to the present embodiment is a video signal that is a signal that needs to preserve the time relationship between transmission and reception, and the line period of the video signal is set to a predetermined value. It is a unit. Therefore, the number of blocks, which are constant information units of the video signal, generated within one line period of the video signal, that is, a plurality of blocks form a predetermined unit.
[0173]
The N-bit counter 54a counts the number of line periods in the input video signal, and determines at what line period the block input to the ECC encoder 12 is input from a predetermined reference. It counts and outputs the value in N bits. Here, the predetermined criterion is a criterion of time, and may be configured to have a common clock between transmission and reception and may be based on a specific time, or may be a block previously transmitted from the transmission side to the reception side. Or a specific signal such as a synchronization signal.
[0174]
That is, the N-bit counter 54a counts the number of lines of the video signal input from the CE terminal based on the timing of the head of the line in synchronization with the basic clock input to the Clock terminal, and outputs the video input from the OE terminal. Based on the timing at which the signal block occurs, that is, an N-bit count value indicating the number of line cycles of the block input to the ECC encoder 12 from a predetermined reference is output.
[0175]
The M-bit counter 55a determines whether a block of a video signal to which a signal is input to the ECC encoder 12 is present from a position serving as a reference of a line cycle, for example, a head position (timing) of a line to which the block belongs, that is, the block of the video signal is an ECC encoder. The time to the position (timing) input to the counter 12 is counted, and the counted value is output as time information in M bits.
[0176]
That is, the M-bit counter 55a synchronizes with the basic clock input to the Clock terminal and resets its count value at the head timing (reset start timing signal) of the line of the video signal input from the Reset terminal. The time from the beginning to the present is continuously counted, and based on the timing at which the block of the video signal input from the OE terminal occurs, the count value, that is, from the head position (timing) of the line, the current, that is, the block of the video signal is A count value representing the time until the position (timing) input to the ECC encoder 12 is output in M bits.
[0177]
Here, in this embodiment, a basic clock of 27 MHz or 36 MHz is used as the basic clock. The information of the basic clock may be reproduced from the carrier transmitted from the transmitting device in the receiving device, or may be transmitted from the transmitting device to the receiving device through a transmission path different from the transmission path transmitting the video signal. Is also good. Similarly to the basic clock, the M-bit counter 55a reproduces a reset start timing signal (RST), which is a signal used as a reference when measuring time information (TS), from a video signal sent from the transmission side to the reception side. Alternatively, the video signal may be transmitted from the transmission side to the reception side on a transmission path different from the transmission path transmitting the video signal.
[0178]
Therefore, as a whole, the N-bit signal output from the N-bit counter 54a is set as the upper bit and the M-bit signal output from the M-bit counter 55a is set as the lower bit, and the time information of a total of (N + M) bits is ECC. It is added to the input signal of the encoder 12.
[0179]
On the other hand, when the ECC encoder 12 is not used, the time information adding means 28 is configured to recognize, for each block, the time information (TS) at which the output signal of the compression means 4 is output. To the buffer 29a. The buffer 29a is provided between the compression means 4 and the synchronization signal addition means 13, and temporarily stores the output signal of the compression means 4, and the buffer 29a uses the information stored within a certain time as one set unit for the synchronization signal addition means. 13 may be used.
[0180]
Next, in the time information reproducing means 30, the predetermined unit delay means 52a includes a time information reading means 56a, a time information accumulating means 57a, an N-bit counter 58a as a first counter, and a comparing means 60a. The delay means 53a comprises a time information reading means 56a, a time information accumulating means 57a, an M-bit counter 59a as a second counter, and a comparing means 60a.
[0181]
The time information reading means 56a is a means for extracting and outputting only the time information assigned to each block from the output signal of the ECC decoder 14.
[0182]
The time information accumulating means 57a sequentially accumulates the value of the time information (TS) extracted by the time information reading means 56a with N bits being higher and M bits being lower, and is sequentially stored. The value of (TS) is output with N bits being higher and M bits being lower. Further, in accordance with an instruction from the time information comparing means 60a to be described later, an output signal of the time information comparing means 60a is input to the buffer 61a, and the time information is stored every time the oldest block stored in the buffer 61a is output from the buffer 61a. The means 57a outputs the oldest time information (TS) next to the currently output time information (TS).
[0183]
The N-bit counter 58a outputs a value from the value (L) of the upper bit (N bit) of the time information (TS) of the block received first to the Load terminal of the N-bit counter 58a to K (K is a natural number of 1 or more). , Which is determined in advance by the time interval between blocks.) (L−K) is loaded. Thereafter, every time the reset start timing signal (RST) supplied from the transmission side is input to the CE terminal, the N-bit counter 58a synchronizes with the reference clock (F) supplied from the transmission side to reset the (LK). It counts (counts up) one by one from the value and outputs the current count value.
[0184]
The M-bit counter 59a resets the count value of the M-bit counter 59a every time a reset start timing signal (RST) supplied from the transmission side is input to the Reset terminal, and the reference clock (F) supplied from the transmission side. ), The M-bit counter 59a counts (counts up) from the reset value (for example, “0”) and outputs the current count value.
[0185]
The time information comparing means 60a outputs the value of the upper bit (N bit) of the time information (TS) which is the output signal of the time information storing means 57a, the output value of the N-bit counter 58a, and the time which is the output signal of the time information storing means 57a. The value of the lower-order bit (M bits) of the information (TS) is compared with the output value of the M-bit counter 59a, and when both of them reach the same value, the buffer 61a is stored in the buffer 61a. It outputs a signal instructing to output the oldest block, and outputs the time information (TS) next to the oldest stored time information (TS) to the time information storage means 57a. And outputs a signal for instructing.
[0186]
The buffer 61a temporarily stores the output signal of the ECC decoder 14, and stores the oldest block stored in the buffer 61a in the expansion unit 11 (variable length decoding unit 15) in accordance with the output signal of the time information comparison unit 60a. Output. The buffer 61a outputs the oldest block stored in the buffer 61a to the decompression unit 11 (variable length decoding unit 15), and then treats the oldest block next to the output block as the oldest block. In this manner, the buffer 61a treats the next oldest block after the sequentially output block as the oldest block every time the oldest block is output.
[0187]
In the present embodiment, a FIFO (First In First Out) memory is used for the time information storage unit 57a and the buffer 61a.
[0188]
On the other hand, when the ECC decoder 14 is not used, the time information reproducing means 30 recognizes the time information added by the time information adding means 28 for each block. The buffer 31a in which the output signal of the synchronizing signal removing means 7 is stored according to the instruction of the time information reproducing means 30 outputs the stored information signal at a timing corresponding to the time information for each block. The buffer 31a may be provided between the synchronizing signal removing means 7 and the decompressing means 11, and may temporarily store the output signal of the synchronizing signal removing means 7.
[0189]
That is, in the transmission device or the transmission method of the present invention, when the line cycle of the video signal is set to the predetermined unit, a block that is a constant information unit of the video signal that is the information signal occurs within one line cycle of the video signal. In the case where the number, that is, a plurality of units form a predetermined unit, the time information described in (Embodiment 5) is output from the compression unit 4 (when the ECC encoder 12 is not used) or the ECC encoder 12 (the ECC encoder 12). 12) when the block of the input information signal (video signal) is output or input at a cycle of a predetermined unit (line) from a predetermined reference, and , From a head position (timing) which is a fixed position (timing) serving as a reference of a predetermined unit (line cycle) of an information signal (video signal) To the position (timing) of the information signal (video signal) output from the compression means 4 (when the ECC encoder 12 is not used) or input to the ECC encoder 12 (when the ECC encoder 12 is used). And time information in a predetermined unit representing time.
[0190]
On the other hand, in the receiving apparatus or the receiving method of the present invention, when the line cycle of the video signal is a predetermined unit, a block which is a constant information unit of the video signal as the information signal occurs within one line cycle of the video signal. In the case where the number, that is, a plurality of units form a predetermined unit, the time information described in (Embodiment 5) is output from the compression unit 4 (when the ECC encoder 12 is not used) or the ECC encoder 12 (the ECC encoder 12). 12, when the block of the input information signal (video signal) is output or input at a predetermined unit (line cycle) from a predetermined reference, and From a head position (timing) which is a fixed position (timing) serving as a reference of a predetermined unit (line cycle) of an information signal (video signal), That is, the time until the position (timing) of the information signal (video signal) output from the compression unit 4 (when the ECC encoder 12 is not used) or input to the ECC encoder 12 (when the ECC encoder 12 is used). Based on the time information added to each information signal (video signal) of this fixed information unit (block) based on the timing corresponding to the time represented by the predetermined unit time information. The information unit (block) having a fixed time represented by the time information within the predetermined unit is delayed from the timing.
[0191]
The operation of the above transmission system will be described below.
[0192]
In the transmission device or the transmission method, the digital video input signal is input to the compression means 4 and the amount of information is compressed. The output signal (FIG. 20 (a)) of the compression means 4 is output to the ECC encoder 12, and at that time, that is, the time information (TS) at which the output signal was output from the compression means 4 or the input signal was input to the ECC encoder 12. Time information (TS) is added to each block as a fixed information unit (FIG. 20B). Here, the time information output by the time information adding means 28 is an N-bit signal output by the N-bit counter 54a, and the block of the video signal is determined by what line cycle the block is based on a predetermined reference. At this time, predetermined unit time information (shown as line numbers: 2, 3,... In FIG. 20) indicating a line number indicating whether the data is output from the compression means 4 or input to the ECC encoder 12 is set as upper bits. A fixed position that is an M-bit signal output by the M-bit counter 55a, where a block of a video signal is output from the compression unit 4 or is a reference of a line cycle to which a block input to the ECC encoder 12 belongs ( From the beginning of the line at (timing), the block is output from the compression means 4 or from the ECC encoder 12 Time information (T1, T2 in FIG. 20) representing the time from the beginning to the position (timing) of the input video signal, that is, the time from the beginning to the position (timing) of the currently input video signal. .. Are written as lower bits. Here, time information (TS21 to TS33, TS (line number) (in-line time)) is added to each of the video signals. In the present embodiment, the basic clock and the reset start timing signal (RST) are transmitted from the transmission side to the reception side via another transmission line.
[0193]
Next, the ECC encoder 12 attaches an error correction code to each video signal and time information (TS21 to TS33) (see FIG. 20C). The output signal of the ECC encoder 12 is temporarily stored in the buffer 29a, and is output to the synchronization signal adding unit 13 using the information stored within a certain time as one set unit. The output signal of the buffer 29a is output to the synchronizing signal adding means 13 and is transmitted via the transmission line after the synchronizing signal is added (FIG. 20 (d)).
[0194]
On the other hand, in the receiving apparatus or the receiving method, after the synchronization signal is removed by the synchronization signal removing means 7 of the received signal (FIG. 20 (e)), the output signal (FIG. 20 (f)) of the synchronization signal removing means 7 becomes The ECC decoder 14 performs signal error correction based on the error correction code. Next, based on the time information (TS21 to TS33) in the output signal (FIG. 20 (g)) of the ECC decoder 14, the video signal is transmitted by the buffer 61a at the same time as when the video signal was input to the ECC encoder 12 at the time of transmission. It is delayed so as to become an interval (FIG. 20 (h)).
[0195]
That is, the block that is the output signal of the ECC decoder 14 is stored in the buffer 61a. On the other hand, the time information (TS) assigned to the block is read by the time information reading means 56a, and the value is stored in the time information storage means 57a. Further, when a new block is output from the ECC decoder 14, the new block is stored in the buffer 61a, time information (TS) corresponding to the block is read, and the value is sequentially stored in the time information storage means 57a. .
[0196]
On the other hand, the value obtained by subtracting K (K is a natural number of 1 or more) from the value (L) of the upper N bits of the time information (TS) of the first received block is stored in the N-bit counter 58a as the first counter. (LK) is loaded, and thereafter, every time a reset start timing signal (RST) supplied from the transmission side is input to the N-bit counter 58a, the output signal of the N-bit counter 58a is counted up by one.
[0197]
The M-bit counter 59a, which is the second counter, is reset every time a reset start timing signal (RST) is supplied from the transmission side, and the output signal of the M-bit counter 59a is reset to a reset value (for example, "0"). Count up one by one.
[0198]
Next, the value of the upper bits (N bits) of the oldest time information (TS), the output value of the N-bit counter 58a, and the lower bits (M) of the oldest time information (TS) stored in the time information storage means 57a. The value of the bit information) and the output value of the M-bit counter 59a are compared by the time information comparing means 60a, and when the two reach an equal value, the output signal of the time information comparing means 60a is stored in the buffer 61a. The buffer 61a instructs to output the oldest block, and outputs the oldest block in accordance with the instruction. The time information accumulating means 57a sends the time information (TS) of the oldest block next to the oldest accumulated time information (TS). The time information (TS) is instructed to be output, and the time information storage means 57a outputs the time information next to the oldest stored time information (TS). And it outputs the (TS).
[0199]
Thereafter, the value of the upper bit (N bit) of the time information of the oldest block next to the oldest block, the output value of the N-bit counter 58a, the value of the lower bit (M bit) of the time information, and the output of the M bit counter 59a The values are compared with each other, and when both reach the same value, a signal is output to the time information storage unit 57a and the buffer 61a, and the buffer 61a outputs the oldest block next to the oldest block (current oldest block). ), And the time information storage means 57a outputs the next oldest time information (TS) next to the oldest stored time information (TS) (the time information (TS) of the oldest block next to the current oldest block). Is output.
[0200]
The same operation as described above is repeated, and the output signal of the buffer 61a is thereafter expanded to become a digital video output signal.
[0201]
Also, as shown in FIG. 18, a predetermined identification number for each predetermined unit (in the present embodiment, a line number assigned to each line, and in FIG. 18, identification numbers 1... Identification number n In a method of transmitting information by adding (where n is a natural number of 1 or more, 1 to n corresponding to a line number) in a synchronization signal or together with a synchronization signal, the N-bit counters 54a and 58a in the present embodiment are used. It can be unnecessary.
[0202]
That is, on the transmitting side, when a plurality of certain information units of the information signal are collected to form a predetermined unit and the predetermined unit has an identification code for identifying each predetermined unit, the time information adding means An M-bit counter 55a, which is a counting unit within a predetermined unit, counts a time from a fixed position (timing) serving as a reference of a predetermined unit of the information signal to a position (timing) to which time information (TS) is added. The feature is that the time information (TS) is a time from a fixed position (timing) that is a reference of a predetermined unit of the information signal to a position (timing) where the time information (TS) is added. It is composed of information of lower bits (M bits), which is time information within a predetermined unit.
[0203]
On the other hand, on the receiving side, when a plurality of certain information units of the information signal are collected to form a predetermined unit and the predetermined unit has an identification code for identifying each predetermined unit, the predetermined unit of the information signal is The lower bits (M bits), which are time information within a predetermined unit, represent the time from a fixed position (timing) serving as a reference to a position (timing) to which time information (TS) is added. Time information reading for delaying a fixed time information unit (block) represented by time information within a predetermined unit of the information signal for each fixed information unit information signal in accordance with the time information added to each information signal of the information unit It comprises a means 56a, a time information accumulating means 57a, an M-bit counter 59a as a second counter, and a comparing means 60a. The lower bits (M bits) of time information in a predetermined unit representing time from a fixed position (timing) serving as a reference of a predetermined unit of the information signal to a position (timing) to which time information (TS) is added, A constant time information unit (block) represented by time information within a predetermined unit of the information signal for each information signal of the constant information unit in accordance with the time information added to the information signal of the constant information unit. ) Is delayed.
[0204]
When one set of information units is assumed to be information accumulated within a certain period of time, for example, the number of blocks generated as a certain information unit within one line cycle of a video signal is collected to form one set of information units. In this case, the N-bit counters 54a and 58a in this embodiment can be omitted.
[0205]
In other words, on the transmitting side, when a plurality of certain information units of the information signal are collected to form a predetermined unit having a certain time length, the time information adding means sets the fixed unit serving as a reference of the predetermined unit of the information signal. An M-bit counter 55a is a counting unit within a predetermined unit for counting the time from the position (timing) that has been set to the position (timing) to which the time information (TS) is added. The lower bits (M), which are time information within a predetermined unit, represent time from a fixed position (timing) where TS) is a reference of a predetermined unit of the information signal to a position (timing) to which the time information (TS) is added. Bit).
[0206]
On the other hand, on the receiving side, when a plurality of certain information units of the information signal are collected to form a predetermined unit having a certain time length, the information unit is obtained by counting the number of the certain information signal or the predetermined unit. The lower bits (M bits), which are time information in a predetermined unit, representing time from a fixed position (timing) serving as a reference of a predetermined unit of an information signal to a position (timing) to which time information (TS) is added, A time-constant information unit (block) represented by time information within a predetermined unit of the information signal for each information signal of the certain information unit in accordance with the time information added for each information signal of the certain information unit And a time information accumulating means 57a, an M-bit counter 59a as a second counter, and a comparing means 60a. Is that the time information (TS) is added from a fixed position (timing) as a reference of a predetermined unit of the information signal in which the time information (TS) is a constant information signal or an information signal obtained by counting the number of predetermined units. The lower bits (M bits), which are time information within a predetermined unit, indicating the time to a position (timing) to be performed, and a certain amount of information according to the time information added to each information signal of this certain information unit In this configuration, a constant time information unit (block) represented by time information within a predetermined unit of the information signal is delayed for each information signal of the unit.
[0207]
With this configuration, the same effect as that of the fifth embodiment can be obtained.
[0208]
In the present embodiment, the time information adding means 28 and the time information reproducing means 30 are provided in (Embodiment 2), but the same effect can be obtained by providing the time information adding means in other embodiments. Is obtained.
[0209]
Although the predetermined unit is one line of the video signal in the present embodiment, the predetermined unit may be any constant interval. Therefore, the predetermined unit may be n lines of the video signal (n is a natural number of 1 or more), or the predetermined unit may be n fields of the video signal and n frames (n is a natural number of 1 or more).
[0210]
Further, the fixed position (timing) of the predetermined unit of the video signal may be any position as long as it is synchronized with one of the line, the field, and the frame.
[0211]
Therefore, it does not necessarily have to be the head of any of the line, field, and frame.
[0212]
Further, when the predetermined unit is one line, a line counter can be used as a number counter, and when a predetermined unit is one field, a field counter is used.
[0213]
(Embodiment 10)
FIG. 21 is a diagram showing a transmission system or a transmission method according to a tenth embodiment of the present invention, and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system or the transmission method. Is a case where the time information at which the signal is output is added for each block). Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0214]
The present embodiment provides another embodiment which is more detailed with respect to the time information adding means 39, the time information reproducing means 40, and the method of adding and reproducing the time information, in particular (Embodiment 6). is there.
[0215]
The time information adding means 39 is composed of an N-bit counter 54b as a predetermined unit counting means 50b and an M-bit counter 55b as a predetermined unit counting means 51b.
[0216]
Here, the information signal handled by the transmitting device or the receiving device of the present invention according to the present embodiment is a video signal that is a signal that needs to preserve the time relationship between transmission and reception, and the line period of the video signal is set to a predetermined value. It is a unit. Therefore, the number of blocks, which are constant information units of the video signal, generated within one line period of the video signal, that is, a plurality of blocks form a predetermined unit line.
[0219]
The N-bit counter 54b counts the number of line cycles in the input video signal, and counts the number of line cycles of the block output by the ECC encoder 12 from a predetermined reference. Then, the value is output in N bits. Here, the predetermined criterion is a criterion of time, and may be configured to have a common clock between transmission and reception and may be based on a specific time, or may be a block previously transmitted from the transmission side to the reception side. Or a specific signal such as a synchronization signal.
[0218]
That is, the N-bit counter 54b counts the number of lines based on the timing of the head of the line of the video signal input from the CE terminal in synchronization with the basic clock input to the Clock terminal, and outputs the video input from the OE terminal. Based on the timing at which the signal block occurs, that is, an N-bit count value representing the number of line cycles of the block output from the ECC encoder 12 from a predetermined reference is output.
[0219]
The M-bit counter 55b outputs the block of the video signal output from the ECC encoder 12 from the position serving as the reference of the line cycle, for example, the head position (timing) of the line to which the block belongs, that is, the block of the video signal is output from the ECC encoder 12. It counts the time until the position (timing) to be performed, and outputs this count value as time information in M bits.
[0220]
In other words, the M-bit counter 55b synchronizes with the basic clock input to the Clock terminal and resets the count value at the head timing (reset timing signal) of the video signal input from the Reset terminal, thereby resetting the line. The time from the beginning to the present is continuously counted, and based on the timing at which the block of the video signal input from the OE terminal occurs, the count value, that is, from the head position (timing) of the line, the current, that is, the block of the video signal is A count value representing the time until the position (timing) output from the ECC encoder 12 is output in M bits.
[0221]
Here, in this embodiment, a basic clock of 27 MHz or 36 MHz is used as the basic clock. The information of the basic clock may be reproduced from the carrier transmitted from the transmitting device in the receiving device, or may be transmitted from the transmitting device to the receiving device through a transmission path different from the transmission path transmitting the video signal. Is also good. Similarly to the basic clock, the M-bit counter 55b reproduces a reset start timing signal (RST), which is a signal used as a reference when measuring the time information (TS), from a video signal sent from the transmitting device to the receiving device. Alternatively, the video signal may be transmitted from the transmission side to the reception side on a transmission path different from the transmission path transmitting the video signal.
[0222]
Accordingly, as a whole, the time information adding means 28 sets the N-bit signal output from the N-bit counter 54b as the high order, and sets the M-bit signal output from the M-bit counter 55b as the low order, so that the total of (N + M) bits of the time information is ECC It is added to the output signal of the encoder 12.
[0223]
On the other hand, when the ECC encoder 12 is not used, the time information adding means 39 is configured to recognize, for each block, the time information (TS) from which the output signal of the compression means 4 is output. To the buffer 29b. The buffer 29b is provided between the compression means 4 and the synchronization signal addition means 13, temporarily stores the output signal of the compression means 4, and the buffer 29b uses the information stored within a certain period of time as one set unit as the synchronization signal addition means. 13 is output.
[0224]
Next, in the time information reproducing means 30, the predetermined unit delay means 52b is composed of a time information reading means 56b, a time information accumulating means 57b, an N-bit counter 58b as a first counter, and a comparing means 60b. The delay unit 53b includes a time information reading unit 56b, a time information storage unit 57b, an M-bit counter 59b as a second counter, and a comparing unit 60b.
[0225]
The time information reading means 56b is a means for extracting and outputting only the time information assigned to each block from the output signal of the synchronization signal removing means 7.
[0226]
The time information accumulating means 57b sequentially accumulates the value of the time information (TS) extracted by the time information reading means 56b every time the value is extracted with N bits being higher and M bits being lower, and the earliest accumulated time information is stored. The value of (TS) is output with N bits being higher and M bits being lower. In accordance with an instruction from the time information comparing means 60b, which will be described later, the output signal of the time information comparing means 60b is input to the buffer 61b, and the time information is stored every time the oldest block stored in the buffer 61b is output from the buffer 61b. The means 57b outputs the next oldest time information (TS) after the currently output time information (TS).
[0227]
The N-bit counter 58b is connected to the Load terminal of the N-bit counter 58b from the value (L) of the upper bit (N bit) of the time information (TS) of the first received block to K (K is a natural number of 1 or more. , Which is determined in advance by the time interval between blocks.) (L−K) is loaded. Thereafter, each time the reset start timing signal (RST) supplied from the transmitting side is input to the CE terminal, the N-bit counter 58b synchronizes with the reference clock (F) supplied from the transmitting side to reset the (LK). It counts (counts up) from the value and outputs the current count value.
[0228]
The M-bit counter 59b resets the count value of the M-bit counter 59b every time a reset start timing signal (RST) supplied from the transmission side is input to the Reset terminal, and outputs a reference clock (F) supplied from the transmission side. ), The M-bit counter 59b counts (counts up) from the reset value (for example, “0”) and outputs the current count value.
[0229]
The time information comparing unit 60b outputs the value of the upper bit (N bit) of the time information (TS) which is the output signal of the time information storing unit 57b, the output value of the N-bit counter 58b, and the time which is the output signal of the time information storing unit 57b. The value of the lower bit (M bit) of the information (TS) is compared with the output value of the M bit counter 59b, and when both of them reach the same value, the buffer 61b stores the value. It outputs a signal instructing to output the oldest block, and outputs the time information (TS) next to the oldest stored time information (TS) to the time information storage means 57a. And outputs a signal for instructing.
[0230]
The buffer 61b temporarily stores the output signal of the synchronizing signal removing means 7, and stores the oldest block stored in the buffer 61b in accordance with the output signal of the time information comparing means 60b, into the expanding means 11 (variable length decoding means 15). ) Is output. The buffer 61b outputs the oldest block stored in the buffer 61b to the decompression unit 11 (variable length decoding unit 15), and then treats the oldest block next to the output block as the oldest block. In this manner, the buffer 61b treats the next oldest block after the sequentially output block as the oldest block every time the oldest block is output.
[0231]
In the present embodiment, a FIFO (First In First Out) memory is used for the time information storage unit 57b and the buffer 61b.
[0232]
On the other hand, when the ECC decoder 14 is not used, the time information reproducing means 40 recognizes the time information added by the time information adding means 39 for each block. The buffer 31b in which the output signal of the synchronizing signal removing means 7 is stored in accordance with the instruction of the time information reproducing means 40 outputs the stored information signal at a timing corresponding to the time information for each block. The buffer 31b may be provided between the synchronizing signal removing means 7 and the decompressing means 11 to temporarily store the output signal of the synchronizing signal removing means 7.
[0233]
That is, in the transmission device or the transmission method of the present invention, when the line cycle of the video signal is set to the predetermined unit, a block that is a constant information unit of the video signal that is the information signal occurs within one line cycle of the video signal. In the case where the number, that is, a plurality of lines form a predetermined unit, the time information described in (Embodiment 6) is obtained by using the compression means 4 (when the ECC encoder 12 is not used) or the ECC encoder 12 (the ECC encoder 12). Is used), a predetermined unit time information indicating the number of a predetermined unit (line) cycle of the block of the information signal (video signal) output from the information signal (video signal), and a predetermined time of the information signal (video signal). From the head position (timing) which is a fixed position (timing) of the unit (line) of the current compression means 4 (using the ECC encoder 12 There case) or the ECC encoder 12 (which is constituted by a predetermined unit in time information indicating the time to the position (timing) of the information signal output from the case of using the ECC encoder 12) (video signal).
[0234]
On the other hand, in the receiving apparatus or the receiving method of the present invention, when the line cycle of the video signal is a predetermined unit, a block which is a constant information unit of the video signal as the information signal occurs within one line cycle of the video signal. In the case where the number, that is, a plurality of lines form a predetermined unit, the time information described in (Embodiment 6) is obtained by using the compression means 4 (when the ECC encoder 12 is not used) or the ECC encoder 12 (the ECC encoder 12). Is used), a predetermined unit time information indicating the number of a predetermined unit (line cycle) of the block of the information signal (video signal) output from the predetermined signal, and an information signal ( From a head position (timing) which is a fixed position (timing) serving as a reference of a predetermined unit (line cycle) of the video signal), Time information in a predetermined unit indicating the time from the compression unit 4 (when the ECC encoder 12 is not used) or the position (timing) of the information signal (video signal) output from the ECC encoder 12 (when the ECC encoder 12 is used) Based on time information added to each information signal (video signal) of this fixed information unit (block), based on the timing corresponding to the time represented by the predetermined unit time information, The information unit (block) having a constant time represented by the time information within the predetermined unit is delayed.
[0235]
The operation of the above transmission system will be described below.
[0236]
In the transmission device or the transmission method, the digital video input signal is input to the compression means 4 and the amount of information is compressed. The output signal of the compression means 4 (FIG. 22 (a)) is output to the ECC encoder 12, and the output signal of the compression means 4 is given an error correction code to each video signal in the ECC encoder 12. Next, the time information (TS) at which the output signal (see FIG. 22B) of the ECC encoder 12 is output is added to each block which is a fixed information unit (FIG. 22C). Here, the time information output by the time information adding means 29 is an N-bit signal output from the N-bit counter 54b, and the block of the video signal is determined by what line cycle the block has from a predetermined reference. , Predetermined unit time information (shown as line numbers: 2, 3,... In FIG. 22) indicating a line number indicating whether the line has been output to the compression means 4 or the ECC encoder 12 is set as an upper bit, and the M bit counter 55b From the top of a line that is a fixed position (timing) that is a reference of a line cycle to which the block output to the compression unit 4 or the ECC encoder 12 belongs. , Until the block reaches the position (timing) of the video signal output from the compression means 4 or the ECC encoder 12. Time information within a predetermined unit (denoted as T1, T2,... In FIG. 22) indicating a time interval, that is, a time from the beginning of the line to the position (timing) of the currently output video signal is set as lower bits. Make up. Here, time information (TS21 to TS33, TS (line number) (in-line time)) is added to each of the video signals. In the present embodiment, the basic clock and the reset start timing signal (RST) are transmitted from the transmission side to the reception side via another transmission line.
[0237]
The output signal of the ECC encoder 12 is temporarily stored in the buffer 29b, and is output to the synchronization signal adding unit 13 using the information stored within a certain time as one set unit. The output signal of the buffer 29b is output to the synchronizing signal adding means 13 and is transmitted via the transmission line after the synchronizing signal is added (FIG. 20 (d)).
[0238]
On the other hand, in the receiving apparatus or the receiving method, after the synchronization signal is removed by the synchronization signal removing unit 7 from the received signal (FIG. 22E), the output signal of the synchronization signal removing unit 7 (FIG. 22F) is On the basis of the time information (TS21 to TS33) in the output signal of the synchronization signal removing means 7, the video signal is delayed by the buffer 61b so as to have the same time interval as the video signal output from the ECC encoder 12 at the time of transmission. (FIG. 22 (g)). Next, the ECC decoder 14 performs signal error correction based on the error correction code (FIG. 22 (h)).
[0239]
That is, the block that is the output signal of the synchronization signal removing unit 7 is stored in the buffer 61b. On the other hand, the time information reading means 56b reads the time information (TS) given to the block, and stores the value in the time information storage means 57b. Further, when a new block is output from the synchronization signal removing means 7, the new block is stored in the buffer 61b, time information (TS) corresponding to the block is read, and the value is sequentially stored in the time information storing means 57b. accumulate.
[0240]
On the other hand, a value obtained by subtracting K (K is a natural number of 1 or more) from the value (L) of the upper N bits of the time information (TS) of the first received block is stored in the N-bit counter 58b as the first counter. (LK) is loaded, and thereafter, every time the reset start timing signal (RST) supplied from the transmission side is input to the N-bit counter 58b, the output signal of the N-bit counter 58b is counted up by one.
[0241]
The M-bit counter 59b, which is the second counter, is reset every time a reset start timing signal (RST) is supplied from the transmission side, and the output signal of the M-bit counter 59b is reset to a reset value (for example, “0”). ) Is incremented by one.
[0242]
Next, the value of the upper bits (N bits) of the oldest time information (TS), the output value of the N-bit counter 58b, and the lower bits (M) of the oldest time information (TS) stored in the time information storage means 59b. Bit) and the output value of the M-bit counter 59b are compared by the time information comparing means 60b, and when the two reach an equal value, the output signal of the time information comparing means 60b is stored in the buffer 61b. The buffer 61b outputs the oldest block in accordance with the instruction and outputs the oldest block to the time information storage means 57b. The time information (TS) is instructed to be output, and the time information storage unit 57b outputs the time information next to the oldest stored time information (TS). And it outputs the (TS).
[0243]
Thereafter, the value of the upper bit (N bit) of the time information of the oldest block next to the oldest block, the output value of the N bit counter 58b, the value of the lower bit (M bit) of the time information, and the output of the M bit counter 59b The values are compared with each other, and when both reach the same value, a signal is output to the time information storage means 57b and the buffer 61b, and the buffer 61b outputs the oldest block next to the oldest block (current oldest block). ), And the time information storage means 57b outputs the next oldest time information (TS) after the oldest stored time information (TS) (the time information (TS) of the oldest block next to the current oldest block). Is output.
[0244]
The same operation as above is repeated, and the output signal of the buffer 61b is thereafter expanded to become a digital video output signal.
[0245]
Also, as shown in FIG. 18, a predetermined identification number for each predetermined unit (in the present embodiment, a line number assigned to each line, and in FIG. 18, identification numbers 1... Identification number n In a method of transmitting information by adding (where n is a natural number of 1 or more, 1 to n corresponding to a line number) in a synchronization signal or together with a synchronization signal, the N-bit counters 54b and 58b in the present embodiment are used. It can be unnecessary.
[0246]
That is, on the transmitting side, when a plurality of certain information units of the information signal are collected to form a predetermined unit and the predetermined unit has an identification code for identifying each predetermined unit, the time information adding means An M-bit counter 55a, which is a counting unit within a predetermined unit, counts a time from a fixed position (timing) serving as a reference of a predetermined unit of the information signal to a position (timing) to which time information (TS) is added. The feature is that the time information (TS) is a time from a fixed position (timing) that is a reference of a predetermined unit of the information signal to a position (timing) where the time information (TS) is added. It is composed of information of lower bits (M bits), which is time information within a predetermined unit.
[0247]
On the other hand, on the receiving side, when a plurality of certain information units of the information signal are collected to form a predetermined unit and the predetermined unit has an identification code for identifying each predetermined unit, the predetermined unit of the information signal is The lower bits (M bits), which are time information within a predetermined unit, represent the time from a fixed position (timing) serving as a reference to a position (timing) to which time information (TS) is added. Time information reading for delaying a fixed time information unit (block) represented by time information within a predetermined unit of the information signal for each fixed information unit information signal in accordance with the time information added to each information signal of the information unit It comprises a means 56b, a time information accumulating means 57b, an M-bit counter 59b as a second counter, and a comparing means 60b, the feature of which is time information (TS). The lower bits (M bits) of time information in a predetermined unit representing time from a fixed position (timing) serving as a reference of a predetermined unit of the information signal to a position (timing) to which time information (TS) is added, A constant time information unit (block) represented by time information within a predetermined unit of the information signal for each information signal of the constant information unit in accordance with the time information added to the information signal of the constant information unit. ) Is delayed.
[0248]
When one set of information units is assumed to be information accumulated within a certain period of time, for example, the number of blocks generated as a certain information unit within one line cycle of a video signal is collected to form one set of information units. In this case, the N-bit counters 54b and 58b in this embodiment can be omitted.
[0249]
In other words, on the transmitting side, when a plurality of certain information units of the information signal are collected to form a predetermined unit having a certain time length, the time information adding means sets the fixed unit serving as a reference of the predetermined unit of the information signal. An M-bit counter 55b, which is a counting unit within a predetermined unit, that counts the time from the set position (timing) to the position (timing) where the time information (TS) is added, is characterized by the time information (TS). The lower bits (M), which are time information within a predetermined unit, represent time from a fixed position (timing) where TS) is a reference of a predetermined unit of the information signal to a position (timing) to which the time information (TS) is added. Bit).
[0250]
On the other hand, on the receiving side, when a plurality of certain information units of the information signal are collected to form a predetermined unit having a certain time length, the information unit is obtained by counting the number of the certain information signal or the predetermined unit. The lower bits (M bits), which are time information in a predetermined unit, representing time from a fixed position (timing) serving as a reference of a predetermined unit of an information signal to a position (timing) to which time information (TS) is added, A time-constant information unit (block) represented by time information within a predetermined unit of the information signal for each information signal of the certain information unit in accordance with the time information added for each information signal of the certain information unit And a time information storage means 57b, an M-bit counter 59b as a second counter, and a comparison means 60b. Is that the time information (TS) is added from a fixed position (timing) as a reference of a predetermined unit of the information signal in which the time information (TS) is a constant information signal or an information signal obtained by counting the number of predetermined units. The lower bits (M bits), which are time information within a predetermined unit, indicating the time to a position (timing) to be performed, and a certain amount of information according to the time information added to each information signal of this certain information unit In this configuration, a constant time information unit (block) represented by time information within a predetermined unit of the information signal is delayed for each information signal of the unit.
[0251]
With this configuration, the same effect as that of the sixth embodiment can be obtained.
[0252]
In the present embodiment, the time information adding means 39 and the time information reproducing means 40 are provided in (Embodiment 2), but the same effect can be obtained by providing the time information adding means in other embodiments. Is obtained.
[0253]
Although the predetermined unit is one line of the video signal in the present embodiment, the predetermined unit may be any constant interval. Therefore, the predetermined unit may be n lines of the video signal (n is a natural number of 1 or more), or the predetermined unit may be n fields of the video signal and n frames (n is a natural number of 1 or more).
[0254]
Further, the fixed position (timing) of the predetermined unit of the video signal may be any position as long as it is synchronized with one of the line, the field, and the frame.
[0255]
Therefore, it does not necessarily have to be the head of any of the line, field, and frame.
[0256]
Further, when the predetermined unit is one line, a line counter can be used as a number counter, and when a predetermined unit is one field, a field counter is used.
[0257]
(Embodiment 11)
FIG. 23 is a diagram showing a transmission system or a transmission method according to an embodiment of the present invention, and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system or the transmission method. Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0258]
In FIG. 23, reference numeral 32 denotes non-compression means for outputting a digital video signal without compressing the information amount. Reference numeral 33 identifies which of the output signal of the variable length encoding means 3 and the output signal of the non-compression means 32 is input, and a signal whose information amount is compressed (hereinafter referred to as a compressed signal) or whose information amount is compressed. Identification signal adding means for adding an identification signal for identifying whether there is no signal (hereinafter, referred to as an uncompressed signal). If the input signal is a compressed signal, the compressed signal block is divided into a plurality of blocks. Collect and output. Numeral 34 denotes a synchronizing signal adding means for adding a synchronizing signal to the output signal of the identification signal adding means 33. When the signal to be transmitted is a compressed signal, a signal obtained by adding one synchronizing signal to a plurality of blocks of video signals is converted into one. If the signal to be transmitted is an uncompressed signal as an aggregate information unit, a signal obtained by adding one synchronization signal to a video signal of one block is output to the coaxial cable 6 as a transmission line as one aggregate information unit (transmission). I do.
[0259]
Reference numeral 35 denotes a synchronization signal removing unit that removes a synchronization signal from the input (received) signal of one set information unit. 36 recognizes whether a compressed signal or an uncompressed signal has been input according to the signal added by the identification signal adding means 33 to the input output signal of the synchronizing signal removing means 35, and recognizes that the compressed signal has been input. When it recognizes that an uncompressed signal is input to an ECC decoder 37 described later, it outputs a signal to a non-decompressing means 38 described later. Numeral 38 denotes a non-expansion means for outputting the input output signal of the identification signal recognizing means 36 without expanding the information amount, and 37 denotes one block which is a predetermined unit of the input output signal of the identification signal recognizing means 36. The ECC decoder detects and corrects an error of a video signal encoded based on each error correction code.
[0260]
In other words, the transmitting device or the transmitting method compresses the information amount of the input video signal and outputs the compressed information amount for each fixed information unit, and collects n units (n is a natural number of 1 or more) of output signals of the compression unit 4. An ECC encoder 12 for adding an error correction signal to the input signal, an uncompressing means 32 for outputting the input information signal for each given set of information units without compressing the information signal, and an ECC encoder when the output signal of the ECC encoder 12 is input. A plurality of output signals of the encoder 12 are collected and output, and when an output signal of the non-compression means 32 is input, one set information unit is output and identification information for adding an identification code for identifying whether or not it is a compressed signal is added. A configuration including an adding unit 33 and a synchronizing signal adding unit 34 for adding one synchronizing signal to the output signal of the identification information adding unit 33, and transmitting the output signal of the synchronizing signal adding unit 34; It was. The feature is that the information signal is a transmission device that collects a plurality of units of a compressed signal of a block, which is a fixed information unit in which the information amount is compressed, and transmits it as one aggregate information unit, and the information amount of the fixed information unit is not compressed. A transmitting device for transmitting one of the information signals, that is, one of the uncompressed signals as one aggregated information unit, adding a signal for identifying which signal is output from which transmitting device, and further adding one synchronization signal Is added to the transmission device or the transmission method.
[0261]
On the other hand, the receiving apparatus or the receiving method receives one synchronization signal and a plurality of units of a compressed information signal or one uncompressed information signal as one aggregate information unit, and converts the synchronization signal among the received signals. A synchronizing signal removing means for removing, an identification signal recognizing means for distributing an output signal of the synchronizing signal removing means in accordance with an identification code for identifying whether or not the signal is a compressed signal; In this case, an ECC decoder 37 for performing error correction of the signal based on the error correction signal for each fixed information unit to which the error correction signal is added, and expansion means for expanding the output signal of the ECC decoder 37 for each predetermined information unit 11 and a non-expansion means 38 for inputting an uncompressed signal among the output signals of the identification signal recognizing means. A receiving device that collects a plurality of compressed signals of a block that is a fixed information unit and receives the same as one collective information unit, and one synchronization signal and one uncompressed signal of a certain information unit as one collective information unit. And a receiver for receiving the information as a set, and identifies whether one set of information signals includes one unit of information signal or a plurality of units of information signal, and selects the receiving apparatus based on the identification result. That is,
[0262]
The transmission system is configured via the transmission path by the transmission device or the transmission method and the reception device or the reception method.
[0263]
The transmission system as described above and the data format transmitted and received by the transmission device and the reception device that constitute the transmission system will be described with reference to FIG.
[0264]
FIG. 24 is a diagram showing a data format in one set information unit. FIG. 24A is a diagram showing the data format of a compressed signal according to the present embodiment, and includes a compressed information signal a (video signal a), a compressed information signal b (video signal b), and a compressed information signal c (video signal c). ) Is a signal obtained by compressing the amount of information of a video input signal into blocks, adding an error correction signal (error correction code) to each of the information signals of one block, collecting a plurality of signals, and adding one synchronization signal to this. In addition, a signal of one set information unit is formed. On the other hand, FIG. 24B is a diagram showing the data format of the uncompressed signal according to the present embodiment. The uncompressed information signal (video signal) is a signal obtained by blocking the information amount of the video input signal without compression. Thus, one information signal of one block and one synchronization signal are added thereto to form a signal of one set information unit.
[0265]
With such a configuration, a plurality of information (signal) sources can be included in one set information unit, and an uncompressed signal can be included by the identification signal, so that signal transmission can be performed efficiently. .
[0266]
In this embodiment, an error correction code is added to a video signal for each block, but an error correction code is added to a video signal for a plurality of units, such as adding an error correction signal for every two blocks (two units) of an information signal. The same effect can be obtained even if the same is performed.
[0267]
In this embodiment, an example is shown in which an apparatus or method for transmitting or receiving an uncompressed information signal is added to that of (Embodiment 2), but other embodiments (Embodiments 1 to A similar effect can be obtained by adding a device or a method for transmitting or receiving an uncompressed information signal to the configuration 5).
[0268]
(Embodiment 12)
FIG. 25 is a diagram showing a data format in one set information unit of the transmission system according to the twelfth embodiment of the present invention. Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted. In addition, the present embodiment is an application in which the (second embodiment) is a SDI standard (Serial Digital Interface) (SMPTE 259M (PROPOSED SMPTE STANDARD FOR TELEVISION 10 Bit 4: 2: 2 Component and 4fsc Composition). .
[0269]
FIG. 25A is a diagram illustrating a data format in one set information unit of the transmission system according to the seventh embodiment of the present invention. FIG. 25A (a) shows the entire data format in one collective information unit. In FIG. 25A (a), Ancillary Data Space is a signal other than the synchronization signal and the information signal, and the video signal itself is not used. This is an area where an auxiliary data signal, which is a necessary information signal, is provided. This Ancillary Data Space is provided with 268 words (1 word = 10 bits). The Active Video Line Space is an area for providing an information signal, and has 1440 words (corresponding to one line of component digital video information).
[0270]
EAV (End of Active Video) is one of the synchronization codes, and is a synchronization code provided immediately after PAYLOAD (Active Area). SAV (Start of Active Video) is one of the synchronization codes, and is a synchronization code provided immediately before PAYLOAD (Active Area). An ANC Data Packet (Ancillary Data Packet) is an area of a HANC (H (horizontal) ANC) between the EAV and the SAV, but refers to optional data supplementarily inserted therein. Here, audio data is inserted and used. The above is the outline of the data format defined by the SDI standard.
[0271]
Next, an embodiment in which the present invention is applied to the SDI standard will be described below. FIG. 25A (b) is a diagram showing the Active Video Line Space in the SDI standard in detail. In FIG. 25A (b), the fixed information unit is 174 words, and the fixed information unit is eight. Together, they form one Active Video Line Space. The remaining 48 words may be filled with blank data as an unused area, but can be used as an additional option such as using auxiliary data.
[0272]
Next, FIG. 25A (c) is a diagram showing in detail a certain information unit of the present embodiment. In FIG. 25A (c), Data Packet Payload is an area where compressed information is provided, and 162 Words are provided. ReedSolomon is an area where an ECC is provided, and is provided with 4 words. Time Stamp is information indicating time, and is provided with three words. The SAD (Source Address) is a device address on the sending side (transmitting side) and can be routed together with the DAD. DAD (Destination Address) is a device address of the receiving side (receiving side). This indicates what data (162 words in DVCPRO) in DT (Data Type) BLOCK is.
[0273]
PT (Packet Type) indicates the type of SDI data packet, and indicates, for example, whether TIME STAMP is valid or invalid. Indicates the effective data length in the WC (Word Count) SDI data packet payload.
[0274]
In this embodiment, the error correction code is added to the video signal for each block. However, as shown in FIGS. 4D and 4E, an error correction signal is added for every two blocks (two units) of the information signal. The same effect can be obtained even if an error correction code is added to a video signal for each of a plurality of units. That is, the transmitting apparatus or the transmitting method is characterized in a transmission system (SDI standard system) that transmits and receives an information signal of M bytes (1440 words in the present embodiment) as one aggregate information unit (Embodiment 1) To (Embodiment 6), the constant information unit of the transmission device or the transmission method is N bytes (M> N, where M and N are natural numbers) (174 words in the present embodiment). .
[0275]
On the other hand, in a receiving apparatus or a receiving method, a feature thereof is that in a transmission system (SDI standard system) for transmitting and receiving an M-byte (1440 words in the present embodiment) information signal as one aggregate information unit (Embodiment 1) -A certain information unit of the receiving device or the receiving method described in (Embodiment 6) is N bytes (M> N, where M and N are natural numbers) (174 words in the present embodiment). .
[0276]
With the above-described configuration, for example, in an existing transmitting apparatus or receiving apparatus in which a data area for providing an information signal is set to be sufficiently large, such as an apparatus using the existing SDI standard, existing equipment is used. Up to this point, a large number of information signals can be included in one set information unit, and signal transmission can be performed efficiently.
[0277]
Next, FIG. 25B is a diagram showing another data format in one set information unit of the transmission system according to the seventh embodiment of the present invention.
[0278]
Here, FIG. 25B (a) is a data format defined by the SDI standard and is the same as FIG. 25A (a).
[0279]
Next, an embodiment in which the present invention is applied to the SDI standard will be described below. FIG. 25B (b) is a diagram showing the Active Video Line Space in the SDI standard in detail. In FIG. 25B (b), the fixed information unit is 171 words, and the fixed information unit is eight. Together, they form one Active Video Line Space. The remaining 72 words may be filled with blank data as an unused area, but can be used as an additional option such as using auxiliary data.
[0280]
Next, FIG. 25B (c) is a diagram showing in detail a certain information unit of the present embodiment. In FIG. 25B (C), DIF Block Data is an area where compressed information is provided. The Block ID is identification information for identifying the content of the compressed information, and is provided with two areas each. TYPE is information indicating a compression method or a stream format, TT (Transmission Type) is information indicating a transfer speed or a video frame number, and ST (Signal Type) is an area in which information indicating a signal format is provided. Data is an information area reserved for a future purpose so that time information can be added, for example, and ECC is an area provided with a 4-byte Reed Solomon code.
[0281]
In this embodiment, the error correction code is added to the video signal for each block. However, as shown in FIGS. 4D and 4E, an error correction signal is added for every two blocks (two units) of the information signal. The same effect can be obtained even if an error correction code is added to a video signal for each of a plurality of units. That is, the transmitting apparatus or the transmitting method is characterized in a transmission system (SDI standard system) that transmits and receives an information signal of M bytes (1440 words in the present embodiment) as one aggregate information unit (Embodiment 1) To (Embodiment 6) is to use a fixed information unit of N bytes (M> N, where M and N are natural numbers) (171 words in the present embodiment). .
[0282]
On the other hand, in a receiving apparatus or a receiving method, a feature thereof is that in a transmission system (SDI standard system) for transmitting and receiving an M-byte (1440 words in the present embodiment) information signal as one aggregate information unit (Embodiment 1) To (Embodiment 6) is to use a fixed information unit of N bytes (M> N, where M and N are natural numbers) (171 words in the present embodiment). .
[0283]
With the above-described configuration, for example, in an existing transmitting apparatus or receiving apparatus in which a data area for providing an information signal is set to be sufficiently large, such as an apparatus using the existing SDI standard, existing equipment is used. Up to this point, a large number of information signals can be included in one set information unit, and signal transmission can be performed efficiently.
[0284]
In this embodiment, the case where the one of the second embodiment is applied to the SDI standard is shown, but the one of the other embodiments (the first to the eleventh embodiments) is applied to the SDI standard. The same effect can be obtained even if the same is performed.
[0285]
(Embodiment 13)
Next, a description will be given of how much code length of an error correction code should be added when a digital signal is transmitted over a coaxial cable to maintain sufficient error correction capability without significantly reducing transmission efficiency.
[0286]
First, as a transmission path, a coaxial cable having a length of attenuation not exceeding 20 dB to 30 dB at a half frequency of the clock (half the carrier frequency) of the digital signal to be transmitted is used.
[0287]
That is, FIG. 26 shows the relationship between the cable length and the amount of attenuation of a 5C2V coaxial cable generally used in a broadcasting station or a studio. In the present embodiment, since the transmission clock frequency of the signal is 270 MHz, the transmission distance (cable length) corresponding to a signal attenuation of 20 dB to 30 dB at half the frequency is 200 m or more when the transmission clock frequency is 270 MHz. It is 280 m, and in the case of 360 MHz, it is 170 m to 250 m. That is, the transmission distance (cable length) corresponding to the range where the signal attenuation amount at half the frequency does not exceed 30 dB is 280 m or less (about 300 m or less) when the transmission clock frequency is 270 MHz and 250 m or less when the transmission clock frequency is 360 MHz. It becomes. The experiment was performed with the length of the 5C2V coaxial cable used in the error rate measurement of the present embodiment set to 200 m and 150 m. The clock frequency was 270 MHz.
[0288]
Using the transmission path as described above, signals under the six conditions shown in (Table 1) were transmitted from a transmitting apparatus as shown in FIG. 27, received by the receiving apparatus, and the error rate was measured.
[0289]
[Table 1]

[0290]
Here, the form of the signal uses a color bar, the jitter added on the transmitting device side has a frequency of 1 MHz to 6 MHz, the jitter amount is 0.7 ns or less, and the signal amplitude is 90% or 100%. did. That is, the jitter was determined by adopting the jitter within the range shown in FIG. FIG. 28 shows a part of the transmission conditions defined by SMPTE259M.
[0291]
Here, the jitter is a time variation with respect to an ideal position (timing) of digital signal transmission, and the timing jitter is a digital signal generated at a frequency larger than a specific frequency (generally, 10 Hz or less). This refers to a change in transmission position (timing). The alignment jitter refers to a positional (timing) variation with respect to a clock extracted (reproduced) from a transmission signal of a digital signal, and a unit interval (hereinafter, referred to as UI) refers to one clock cycle time. , Corresponds to the nominal minimum time between transmissions of the serial signal. The transmission method of the signal transmitted on the wired transmission path used by the inventors in this experiment is within the range specified by the SMPTE259M standard or SMPTE292M standard.
[0292]
Error detection was performed on a field unit by an error measuring instrument, and the number of errors was counted up. The error rate and error occurrence interval were calculated from the measurement time and the number of errors. Since error detection is performed in units of fields, it is assumed that even if the number of errors in units of fields is 1 bit or more, there is one error in one field as a measurement result. Therefore, the actual error rate may be further worse than the error rate measurement result described below, because error propagation due to descrambling and a plurality of errors occurring in one field can be considered.
[0293]
The results of experiments performed by the inventor under the above conditions are shown in (Table 2) to (Table 7).
[0294]
[Table 2]

[0295]
[Table 3]

[0296]
[Table 4]

[0297]
[Table 5]

[0298]
[Table 6]

[0299]
[Table 7]

[0300]
Where the error rate is
Error rate = number of errors / (measurement time × 270 Mbps)
Is calculated.
[0301]
Even under the above conditions, the error rate is 1 × 10 in a severe transmission environment. ^-8 In some cases. When transmitting a conventional uncompressed digital video signal, this error rate is hardly detectable with the naked eye, so there is no practical problem.
[0302]
However, when a compressed signal such as MPEG (Moving Picture Experts Group) or DVC (Digital Video Cassette) is transmitted, as shown in FIG. 5, a 1-bit error is generated in a DCT area unit, a slice unit, or a GOP (Group of). This causes error propagation in units of Picture, resulting in large image quality deterioration. The degree of influence of the image quality degradation differs depending on the compression algorithm and the place where the bit error has occurred, but in any case, there is a practical problem unless any error countermeasures are taken.
[0303]
For example, when transmitting a compressed signal having a transmission rate of 27 Mbps (bit per second) under the condition of a clock frequency of 270 MHz, the bit error rate is “1 × 10 ^-11 ”, The average error occurrence interval is about 1 hour, and the bit error rate is“ 1 × 10 ^-Ten , The average error occurrence interval is about 6 minutes, and the bit error rate is “1 × 10 ^-9 ”, The average error occurrence interval is about 37 seconds, and the bit error rate is“ 1 × 10 ^-8 , The average error occurrence interval is about 3.7 seconds, so that the transmission parameters cannot be put to practical use even under the above conditions.
[0304]
Here, as a countermeasure against errors, there is a method of retransmitting an erroneous packet. However, in this method, a transmission time due to retransmission is delayed and a one-way transmission system (for example, SMPTE 259M) realizes a retransmission mechanism. Is difficult.
[0305]
On the other hand, in the method of adding an error correction code, the ratio of information signals included in a signal to be transmitted is reduced, so that transmission efficiency is reduced. If the code length of the error correction code is reduced in order to reduce the additional information, the error correction capability will be reduced. Therefore, the problem is how much code length of an error correction code can be added to maintain sufficient error correction capability without significantly reducing transmission efficiency.
[0306]
The present embodiment solves such a problem, and the following describes in detail how much code length of an error correction code should be added together with the reason.
[0307]
FIG. 29 is a diagram illustrating the error correction capability of the Reed-Solomon code. Here, BER (Bit Error Rate) shown on the horizontal axis of FIG. 29 represents a bit error rate, that is, a bit error occurrence rate on a transmission path, and Pbe (Block error rate) shown on the vertical axis of FIG. Represents the block error rate, that is, the rate of occurrence of blocks that could not be corrected even after error correction.
[0308]
In FIG. 29, the block length N is 255 bytes (1 byte = 8 bits), which is the maximum block length when an 8-bit Reed-Solomon code is added. FIG. 29 is a diagram in which error propagation by a scrambled NRZI code is also taken into consideration. That is, in this system, randomization is performed so that digital signals 1 and 0 are generated on the transmission path on average. In this method, when an error occurs, the error propagates to 6 bits out of the following 11 bits. Therefore, every time a 1-bit error occurs, the error propagates over 2 words (1 word = 10 bits). Therefore, the error correction capability of the Reed-Solomon code must be T = 2 or more (that is, the error correction code is at least 4 bytes or more).
[0309]
Note that the error correction code itself is also included in the block. When the error correction code is fixed, the correction capability decreases as the block length increases, and FIG. 29 shows the correction capability when the error correction capability is the lowest.
[0310]
Here, T represents the number of symbols (bytes) that can be corrected in one block. For example, when a 4-byte Reed-Solomon (error correction) code is added to a block, two symbols (bytes) in one block ) Can be corrected (T = 2), and when a 2-byte Reed-Solomon (error correction) code is added, a symbol (byte) error of up to one symbol (byte) in one block is obtained. Are correctable (T = 1). Also, T = 0 indicates a case where no error correction code is added.
[0311]
Next, from Tables 2 to 7 and FIG. 9, how much error correction code should be added will be described in detail together with the reason.
[0312]
From the error rate measurement results shown in (Table 2) to (Table 7), even if the transmission parameters are within the above-mentioned conditions (the conditions in the SMPTE 259M standard), the bit error rate can be obtained under severe conditions. Is 1 × 10 ^-8 There are cases when it becomes. Therefore, with reference to FIG. 29, it will be examined whether a sufficient error correction capability can be maintained when a 2n-byte (T = n) (n is a natural number of 1 or more) Reed-Solomon (error correction) code is added.
[0313]
(1) When a 2-byte (T = 1) Reed-Solomon (error correction) code is added, the bit error rate is 1 × 10 ^-8 Then, a 2-byte (T = 1) read Solon code is added, and error correction is performed using the code. As a result, the block error rate becomes about 1 × 10 ^-9 To be improved. This value corresponds to an error occurrence interval that a block error occurs once every 26 hours assuming that a compressed signal having a transmission speed of 27 Mbps is transmitted. Therefore, it is difficult to perform sufficient error correction by performing error correction using a 2-byte (T = 1) Reed-Solomon code.
[0314]
In this embodiment, since the error propagation by the scrambled NRZI code is also considered, the error correction capability of the Reed-Solomon code is T = 2 or more (that is, the error correction code has a minimum of 4 bytes). ), And a 2-byte (T = 1) Reed-Solomon (error correction) code has no meaning in the present embodiment.
[0315]
(2) When a 4-byte (T = 2) Reed-Solomon (error correction) code is added, the bit error rate is 1 × 10 ^-8 Then, a 4-byte (T = 2) Reed-Solomon code is added, and error correction is performed using the code. ^-13 To be improved. This value corresponds to an error occurrence interval that a block error occurs about once every ten years when a compressed signal having a transmission rate of 27 Mbps is transmitted. Therefore, sufficient error correction can be performed by performing error correction using a 4-byte (T = 2) Reed-Solomon code.
[0316]
As described above, the Reed-Solomon code is used as an error correction code, and its length is set to four words (T = 2), thereby satisfying both conditions of reducing additional information and obtaining sufficient error correction capability. be able to.
[0317]
When the Reed-Solomon code and the parity bit added for each byte of the information signal are used together, the symbol (byte) position where the error has occurred can be known. As a result, the error location is detected by the parity bit in the receiving apparatus or the receiving method, and then the error is corrected by the Reed-Solomon code, so that the error correction capability is as follows.
[0318]
When four error bytes in one block are detected by the detection of the parity error, the error of the four bytes can be corrected. When three error bytes in one block are detected by the parity error detection, If the error of three bytes can be corrected, and if two error bytes in one block are detected by the parity error detection, the error of the two bytes and the other one byte whose position is unknown can be corrected. When one error byte in one block is detected by the parity error detection, the error of the one byte error and the other one byte whose position is unknown can be corrected, and the error byte in one block is detected by the parity error detection. If not, it is possible to correct an error of 2 bytes whose position is unknown in one block.
[0319]
As described above, according to the above-described configuration, it is possible to add a Reed-Solomon (error correction) code and realize substantial error-free.
[0320]
Further, according to the above configuration, an error-free environment can be guaranteed by adding a common error correction code regardless of the compression method.
[0321]
Furthermore, by making the error correction a common packet format, the total cost for interconnection can be reduced. That is, even if the compression means is changed to various types, by using a common Reed-Solomon (error correction) code, the configuration of the device constituting the code can be made common, and the cost can be reduced.
[0322]
(Embodiment 14)
FIG. 30 is a diagram illustrating a transmission system or a transmission method according to a fourteenth embodiment of the present invention, and a transmission device or a transmission method and a reception device or a reception method constituting the transmission system or the transmission method. Note that components already described in the above embodiment use the same reference numerals, and description thereof will be omitted.
[0323]
Here, a block which is a fixed information unit in the present embodiment is N rows × J columns (in the present embodiment, N = 8, J = 170, and (8 × 170) bits = 170 bytes). It is composed of A line as a predetermined unit can be constituted by an information signal having a predetermined information amount or less, and each word constituting the line is N rows (N-bit rows) (N is a natural number of 1 or more, and the present embodiment) In the embodiment, it is assumed that N = 8), and a first region in which a video signal as a substantial information signal is arranged and M rows (M-bit rows) (M is a natural number of 1 or more, and this embodiment In the embodiment, M = 2.) And a second area in which a redundant parity signal is arranged (N + M = 10 bits). For example, when the transmission speed between transmission and reception is 270 Mbps, it is 1440 words, and when it is 360 Mbps, it is 1920 words (1 word = 10 bits). Here, the maximum information amount that can constitute a line, which is a predetermined unit, that is, a constant information amount is (N rows × I columns) bits, and in this embodiment, N = 8 and I = 1440. (When the transmission rate is 270 Mbps) or 1920 (when the transmission rate is 360 Mbps).
[0324]
In FIG. 30, reference numeral 70 denotes an output signal of the ECC encoder 12 according to the information amount of an information signal input in units of blocks (N rows × J columns, 8 × 170 in the present embodiment) each being a constant information unit. That is, it is possible to configure a first region of N rows (N-bit rows) in which substantial information signals are arranged among words forming a line in which the information amount of an input information signal is a predetermined unit. If the amount of information exceeds a certain amount of information (ie, N rows × I columns, 8 × 1440 (when the transmission rate is 270 Mbps) or 8 × 1920 (when the transmission rate is 360 Mbps) in this embodiment), the ECC encoder 12 8-9 conversion means, which is an XY conversion means capable of arranging at least a part of the video signal of the output signal composed of (M rows × J columns) in the second area. The output signal of the 8-9 conversion means 70 is output to the synchronization signal adding means 13.
[0325]
On the other hand, when the ECC encoder 12 is not used, the output signal (N rows × J columns) of the compression means 4 is changed according to the information amount of the input information signal, that is, the information amount of the input information signal is set to a predetermined unit. The output signal of the compression means 4 when the amount of information exceeds a certain amount of information that can constitute a first region of N rows (rows of N bits) where a substantial information signal is arranged in each word constituting a line 8-9 conversion means, which is an XY conversion means capable of arranging at least a part of the video signal in the second area, and outputting the output signal of the 8-9 conversion means 70 to the synchronization signal adding means 13. do it.
[0326]
Reference numeral 71 denotes a signal which can be rearranged in the first area from among the output signals of the synchronizing signal removing means 7 over the second area, ie, N rows × J columns (8 × in the present embodiment). 170-8) is a 9-8 conversion means which is a YX conversion means configured to be able to restore to a block which is a fixed information unit. The output signal of the 9-8 conversion means 71 is output to the ECC decoder 14.
[0327]
On the other hand, when the ECC decoder 14 is not used, the video signal arranged in the second area among the output signals of the synchronization signal removing means 7 can be rearranged only in the first area, that is, N rows × J columns 9-8 conversion means, which is a YX conversion means configured to be able to be restored to a block (8 × 170 in this embodiment), which is a constant information unit, and expands the output signal of the 9-8 conversion means 71 What is necessary is just to make it the structure output to the means 11.
[0328]
That is, in the transmitting apparatus or the transmitting method, in the above-described (Embodiment 1) or (Embodiment 2), the block that is a fixed information unit has N rows (N-bit rows) (this embodiment , N = 8, and is an 8-bit row.) × J columns. A line, which is a predetermined unit, can be constituted by an information signal having a predetermined information amount or less, and each word constituting the line is composed of N rows, N bits (N is a natural number of 1 or more) and a substantial information signal. When there is a first area in which a video signal as a signal is arranged and a second area in which M rows (M is a natural number of 1 or more) and a parity signal as a redundant signal are arranged N bits in which a substantial information signal is arranged according to the information amount of the input information signal, that is, in each word constituting a line in which the information amount of the input information signal is a predetermined unit. When at least a certain amount of information that can configure the first area is used, at least a part of a video signal, which is a substantial information signal, can be arranged in the second area.
[0329]
On the other hand, in the receiving apparatus or the receiving method, in the above (Embodiment 1) or (Embodiment 2), the block which is a fixed information unit has N rows (N-bit rows) (this embodiment , N = 8.) × J columns. Further, a line as a predetermined unit can be constituted by an information signal having a predetermined information amount or less, and each word constituting the line is N rows (N-bit row) (N is a natural number of 1 or more) and substantially. And a second area where M rows (M is a natural number of 1 or more) and a parity signal or the like, which is a redundant signal, are arranged. Thus, a video signal, which is a substantial information signal arranged over the second region, can be rearranged only in the first region, that is, N rows (N-bit rows) (in the present embodiment, 8 rows). The configuration is such that it can be restored to a block which is a constant information unit of (row of bits) × J columns.
[0330]
Such a transmission device or transmission method and a reception device or reception method constitute a transmission system or transmission method via a transmission path.
[0331]
The operation of the above transmission system will be described with reference to FIG.
[0332]
FIG. 31 is a diagram showing a data format in a block as a fixed information unit of the transmission system according to the fourteenth embodiment of the present invention.
[0333]
In FIG. 30, in the transmission device or the transmission method, the digital video input signal is input to the compression means 4 to compress the information amount. The output signal of the compression means 4 is input to the ECC encoder 12, where the ECC encoder 12 applies an error correction code to each information signal. The output signal of the ECC encoder 12 is input to an 8-9 conversion means 70, which is an XY conversion means, where the information amount of the input information signal is predetermined. If the amount of information exceeds a certain amount that can form the first region of N rows (N-bit rows) in which substantial information signals are arranged among the words constituting the line that is a unit of FIG. As shown in (2), in each block of the output signal of the ECC encoder 12, at least a part of the video signal (see FIG. 31A) existing only in the first area (corresponding to the areas B0 to B7) is converted to the second area. (Corresponding to B8 or B8 and B9) in the area where the parity signal exists (see FIG. 31B). At this time, the parity signal existing in the second area is discarded. Further, when a space is generated in the first area when the dummy signal is arranged in the area where the parity signal exists, a pseudo signal (dummy signal) is inserted. Thereafter, a signal is output to the synchronization signal adding means 13.
[0334]
On the other hand, a first region of N rows (N-bit rows) in which a substantial information signal is arranged among words constituting a line in which the information amount of the input information signal is a predetermined unit can be configured. If the information amount does not exceed a certain amount, the output signal of the ECC encoder 12 is output to the synchronization signal adding means 13 as it is.
[0335]
On the other hand, in the receiving apparatus or the receiving method, after the synchronization signal is removed by the synchronization signal removing unit 7 from the received signal, the output signal of the synchronization signal removing unit 7 is passed through the 9-8 conversion unit 71 to the second area. If there is a video signal that is arranged in the first area, it can be rearranged in the first area, that is, restored to a block that is a fixed information unit of N rows (N-bit rows, 8 bits in the present embodiment) × J columns. Inverse configuration is performed according to a configuration that can be performed, that is, a rule at the time of 8-9 conversion on the transmission side, and the state is restored to the same state as before the 8-9 conversion is performed. The error correction of the output signal of the 9-8 conversion means 71 is performed by the ECC decoder 14 based on the error correction code added for each block. Thereafter, the output signal of the ECC decoder 14 is expanded by the expansion unit 11 to become a digital video output signal.
[0336]
By adopting such a configuration, it is possible to cope with a case where there are many input information signals and a case where transmission and reception cannot be performed in a predetermined unit.
[0337]
Here, in FIG. 31, TYPE represents the type of compressed data, and for example, DVCPRO is 221h. In addition, MPEG has a type for MPEG. . REV is an abbreviation of Reserved (reserved), and is an area reserved so that a new bit can be defined for the future in the standard and that the user does not use it without permission. Next, ST is an abbreviation of Signal Type and represents a signal format. The DVCPRO has a field frequency of 50 Hz / 60 Hz (59.94 Hz) or a difference in the number of samples of a luminance signal and a chrominance signal. TT is an abbreviation of Transmission Type, and represents a transfer format. It is used to identify various transfer formats such as 4 × speed transfer and 8 × speed transfer as well as 1 × speed transfer of normal reproduction, and to identify frames.
[0338]
Note that in this embodiment, the XY conversion means 70 and the YX conversion means 71 are provided in (Embodiment 1) or (Embodiment 2), but they are provided in other embodiments. Has the same effect.
[0339]
In the present embodiment, the XY conversion means 70 and the YX conversion means 71 are configured to be able to switch between XY conversion and YX conversion or not. -X conversion may be adopted.
[0340]
【The invention's effect】
With the above configuration, a large number of information signals can be included in one set information unit, and signal transmission can be performed efficiently.
[Brief description of the drawings]
FIG. 1 is a diagram showing a transmission system according to a first embodiment of the present invention, and a transmission device and a reception device constituting the transmission system.
FIG. 2 is a diagram showing a data format in one set information unit of the transmission system according to the first embodiment of the present invention;
FIG. 3 is a diagram showing a transmission system according to a second embodiment of the present invention, and a transmission device and a reception device constituting the transmission system.
FIG. 4 is a diagram showing a data format in one set information unit of the transmission system according to the second embodiment of the present invention;
FIG. 5A is a conceptual diagram illustrating a case where an error occurs in one place in an uncompressed system.
(B) is a conceptual diagram showing a case where an error has occurred at one place in the compression system, in which a square area of pixels is treated as one area.
(C) is a conceptual diagram showing a case where an error occurs in one place in the compression system, and shows a case where an area of one line of pixels is treated as one area.
(D) is a conceptual diagram showing a case where an error has occurred at one place in the compression system, in which the entire screen area is treated as one area.
FIG. 6 is a diagram showing a transmission system according to a third embodiment of the present invention, and a transmission device and a reception device constituting the transmission system.
FIG. 7 is a diagram showing a data format in one set information unit of the transmission system according to the third embodiment of the present invention;
FIG. 8 is a diagram showing a transmission system according to a fourth embodiment of the present invention, and a transmission device and a reception device constituting the transmission system.
FIG. 9 is a diagram showing a data format in one set information unit of the transmission system according to the fourth embodiment of the present invention.
FIG. 10 is a diagram showing a transmission system according to a fifth embodiment of the present invention and a transmission device and a reception device that constitute the transmission system (the time of an input signal input to the ECC encoder 12 in the time information adding means 28); When dealing with information)
FIG. 11 is a diagram showing a data format in one set information unit of the transmission system according to the fifth embodiment of the present invention.
FIG. 12 is a diagram showing a transmission system according to a sixth embodiment of the present invention and a transmission device and a reception device that constitute the transmission system (time information of an output signal output by the ECC encoder 12 in the time information addition means 39); When dealing with
FIG. 13 is a diagram showing a data format in one set information unit of the transmission system according to the sixth embodiment of the present invention.
FIG. 14 is a diagram showing a transmission system according to a seventh embodiment of the present invention and a transmission device and a reception device that constitute the transmission system (the time of an input signal input to the ECC encoder 12 by the time information adding unit 28); When dealing with information)
FIG. 15 is a diagram showing a data format in one set information unit on the transmission side of the transmission system according to the seventh embodiment of the present invention.
FIG. 16 is a diagram showing a transmission system according to an eighth embodiment of the present invention and a transmission device and a reception device that constitute the transmission system (time information of an output signal output from the ECC encoder 12 in the time information adding means 39); When dealing with
FIG. 17 is a diagram showing a data format in one set information unit on the receiving side of the transmission system according to the eighth embodiment of the present invention;
FIG. 18 is a diagram showing a data format in another aggregate information unit of the transmission system according to the seventh embodiment or the eighth embodiment of the present invention.
FIG. 19 is a diagram showing a transmission system according to a ninth embodiment of the present invention and a transmission device and a reception device constituting the transmission system (the time of the input signal input to the ECC encoder 12 in the time information adding means 28); When dealing with information)
FIG. 20 is a diagram showing a data format in one set information unit on the transmission side of the transmission system according to the ninth embodiment of the present invention;
FIG. 21 is a diagram showing a transmission system according to a tenth embodiment of the present invention, and a transmission device and a reception device constituting the transmission system (time information of an output signal output by the ECC encoder 12 in the time information adding means 39); When dealing with
FIG. 22 is a diagram showing a data format in one set information unit on the receiving side of the transmission system according to the tenth embodiment of the present invention.
FIG. 23 is a diagram showing a transmission system according to an eleventh embodiment of the present invention, and a transmission device and a reception device constituting the transmission system.
FIG. 24A shows a data format of a compressed signal according to the eleventh embodiment of the present invention.
(B) A diagram showing a data format of an uncompressed signal according to the eleventh embodiment of the present invention.
FIG. 25 is a diagram showing a data format in one set information unit of the transmission system according to the twelfth embodiment of the present invention.
FIG. 26 is a diagram showing the relationship between the cable length and attenuation of a commonly used 5C2V coaxial cable.
FIG. 27 is a diagram showing a transmitting device and a receiving device used in the thirteenth embodiment of the present invention.
FIG. 28 is a diagram showing details of jitter of a signal used in the thirteenth embodiment of the present invention.
FIG. 29 is a diagram showing an error correction capability of a Reed-Solomon code.
FIG. 30 is a diagram illustrating a transmission system according to a fourteenth embodiment of the present invention, and a transmission device and a reception device included in the transmission system.
FIG. 31 is a diagram showing a data format in one set information unit on the receiving side of the transmission system according to the fourteenth embodiment of the present invention.
FIG. 32 is a diagram showing a conventional transmission system.
[Explanation of symbols]
1 discrete cosine transform means
2 Quantization means
3 Variable length coding means
4 Compression means
5, 13 synchronization signal adding means
6 Transmission line
7 Synchronous signal removal means
8, 15, 19, 25 Variable length decoding means
9 Inverse quantization means
10 Discrete cosine inverse transformation means
11 Extension means
12, 17, 22 ECC encoder
14 ECC decoder
16, 21, 23 synthesis means
18 Distribution means
20 Shuffling means
24 Deshuffling means
26 Non-compression means
27 Non-expansion means
28 Time information adding means
29, 31 buffers
30 hour information reproducing means

Claims (42)

Compression means for compressing the information amount of the input information signal and outputting the information signal for each fixed information unit, and an ECC encoder for collecting n units (n is a natural number of 1 or more) of the output signals of the compression means and adding an error correction signal And one or more of the predetermined information units form a predetermined unit, and the predetermined unit is N rows (N is a natural number of 1 or more) and a first information unit in which a substantial information signal is arranged. A second area in which an area and M rows (M is a natural number of 1 or more) and redundant signals are arranged, and wherein the predetermined unit can be constituted by an information signal having a predetermined information amount or less. X-Y conversion means having a configuration in which at least a part of a substantial information signal of the output signal of the ECC encoder can be arranged in the second area according to the information amount of the input information signal; A plurality of output signals of the XY conversion means And a synchronizing signal adding means for adding one synchronizing signal thereto with collecting position, transmitting apparatus configured to transmit an output signal of the synchronizing signal adding means. It has a plurality of compression means for compressing the information amount of the input information signal and outputting it for each fixed information unit, and selects output signals of each of the plurality of compression means for each fixed information unit and outputs them in series. Synthesizing means, an ECC encoder that collects n units (n is a natural number of 1 or more) of output signals of the synthesizing means and adds an error correction signal, and one or more of the certain information units to form a predetermined unit The predetermined unit is N rows (N is a natural number of 1 or more), and the first area in which a substantial information signal is arranged and M rows (M is a natural number of 1 or more) and a redundant signal And the predetermined unit can be configured with an information signal of a certain information amount or less, and the ECC encoder of the ECC encoder according to the information amount of the input information signal. The output signal has a substantial information signal XY conversion means having at least a part of which can be arranged in the second area, and a synchronization signal addition means for collecting a plurality of output signals of the XY conversion means and adding one synchronization signal thereto Means for transmitting an output signal of the synchronization signal adding means. Compression means for compressing the information amount of the input information signal and outputting the information signal for each fixed information unit; non-compression means for outputting the input information signal for each fixed information unit without compressing the information signal; A combining means for selecting each output signal of the non-compressing means for each predetermined information unit and outputting the selected signal in series, and an n-unit (n is a natural number of 1 or more) output signals of the combining means for collecting an error correction signal And an ECC encoder that adds one or more of the predetermined information units to form a predetermined unit, wherein the predetermined unit is N rows (N is a natural number of 1 or more) and a substantial information signal is allocated. And a second area in which M rows (M is a natural number of 1 or more) and redundant signals are arranged, and the predetermined unit is constituted by an information signal of a certain information amount or less. Where possible, the information entered XY conversion means having a configuration in which at least a part of a substantial information signal of the output signal of the ECC encoder can be arranged in the second area according to the information amount of the signal; A transmitting apparatus comprising: a synchronizing signal adding unit that collects a plurality of output signals and adds one synchronizing signal thereto, and transmits an output signal of the synchronizing signal adding unit. Compression means for compressing the information amount of the input information signal and outputting the information signal for each fixed information unit, and an ECC encoder for collecting n units (n is a natural number of 1 or more) of the output signals of the compression means and adding an error correction signal A non-compressing means for outputting the input information signal for each fixed information unit without compressing the information signal; and collecting and outputting a plurality of units of the output signal of the ECC encoder when the output signal of the ECC encoder is input. And when the output signal of the non-compression means is input, identification information adding means for outputting one set information unit and adding an identification code for identifying whether the information amount is a compressed signal or not, One or more fixed information units are gathered to form a predetermined unit, the predetermined unit is N rows (N is a natural number of 1 or more), and a first area in which a substantial information signal is arranged and M Line (M is 1 or more And a second area in which a redundant signal is arranged, and the predetermined unit can be constituted by an information signal having a certain amount of information or less. XY conversion means having a configuration in which at least a part of a substantial information signal of the output signal of the identification information addition means can be arranged in the second area in accordance with the amount of information; A transmitting device comprising: a synchronizing signal adding means for adding one synchronizing signal to an output signal; and transmitting an output signal of the synchronizing signal adding means. A compression unit for compressing the information amount of the input information signal and outputting the information unit for each fixed information unit; collecting n units (n is a natural number of 1 or more) of output signals of the compression unit to form a predetermined unit; The predetermined unit is N rows (N is a natural number of 1 or more), a first area where substantial information signals are arranged, and M rows (M is a natural number of 1 or more) and redundant signals are arranged. And the predetermined unit can be composed of an information signal having a predetermined information amount or less, and the output unit of the compression unit outputs the information signal in accordance with the information amount of the input information signal. XY conversion means having a configuration in which at least a part of a substantial information signal can be arranged in the second area; and a plurality of output signals of the XY conversion means are collected and one synchronizing signal is added thereto. Synchronizing signal adding means for adding the synchronizing signal. Configuration and the transmitter for transmitting the output signal of the pressurizing means. It has a plurality of compression means for compressing the information amount of the input information signal and outputting it for each fixed information unit, and selects output signals of each of the plurality of compression means for each fixed information unit and outputs them in series. Synthesizing means, and an output signal of the synthesizing means is collected into n units (n is a natural number of 1 or more) to form a predetermined unit, and the predetermined unit is N rows (N is a natural number of 1 or more) and substantially And a second area where M rows (M is a natural number of 1 or more) and redundant signals are arranged, and the predetermined unit is a fixed amount of information. In the case where the information signal can be constituted by the following information signals, at least a part of a substantial information signal of the output signal of the compression unit can be arranged in the second area according to the information amount of the input information signal. XY conversion means having the above configuration, and the XY conversion means And a synchronizing signal adding means for adding one synchronizing signal thereto with an output signal collect multiple units, transmitting apparatus configured to transmit an output signal of the synchronizing signal adding means. Compression means for compressing the information amount of the input information signal and outputting the information signal for each fixed information unit; non-compression means for outputting the input information signal for each fixed information unit without compressing the information signal; A synthesizing means for selecting each output signal of the non-compressing means for each predetermined information unit and outputting the information in series; and a unit which collects the output signals of the synthesizing means into n units (n is a natural number of 1 or more) and Where the predetermined unit is N rows (N is a natural number of 1 or more), and the first area where a substantial information signal is arranged and M rows (M is a natural number of 1 or more) and redundant. And a second area in which a predetermined signal is arranged, and the predetermined unit can be constituted by an information signal of a certain information amount or less, and the compression is performed in accordance with the information amount of the input information signal. At least part of the substantial information signal of the output signal of the means XY conversion means configured to be arranged in the second area, and synchronization signal addition means for collecting a plurality of units of output signals of the XY conversion means and adding one synchronization signal thereto. A transmitting device configured to transmit an output signal of the synchronization signal adding means. Compression means for compressing the information amount of an input information signal and outputting the information signal for each fixed information unit; non-compression means for outputting the input information signal for each fixed information unit without compressing the information signal; When the output signal is input, a plurality of output signals of the compression means are collected and output, and when the output signal of the non-compression means is input, one set information unit is output and the amount of information is compressed. Identification information adding means for adding an identification code for identifying whether or not the signal is a given signal, and one or more of the predetermined information units are collected to form a predetermined unit, and the predetermined unit is N rows (N is 1 or more). And a second area in which M information (M is a natural number equal to or greater than 1) and a redundant signal are arranged, and the first area in which a substantial information signal is arranged and the second area in which redundant signals are arranged. Is an information signal of a certain amount of information or less. A configuration in which at least a part of a substantial information signal of an output signal of the identification information adding means can be arranged in the second area according to an information amount of the input information signal. And a synchronizing signal adding means for adding one synchronizing signal to the output signal of the XY converting means, and transmitting the output signal of the synchronizing signal adding means. 9. The transmission device according to claim 1, wherein the redundant signal is constituted by a parity signal. One synchronous signal and a compressed information signal of a fixed information unit are added as an error correction signal for every n units (n is a natural number of 1 or more) and transmitted as one collective information unit, and the fixed information unit is transmitted. Are gathered to form a predetermined unit, wherein the predetermined unit is N rows, and a first area where substantial information signals are arranged and M rows (M is a natural number of 1 or more) ) And a second area in which a redundant signal is arranged, and the predetermined unit can be constituted by an information signal having a predetermined information amount or less, and the information amount of the input information signal is A transmission device configured to be able to arrange at least a part of the substantial information signal in the second area in accordance with One synchronizing signal and a compressed information signal of a certain information unit are collected as n units (n is a natural number of 1 or more) and transmitted as one set information unit. Where the predetermined unit is N rows, the first area in which a substantial information signal is arranged, and M rows (M is a natural number of 1 or more) and a redundant signal. And the second unit is arranged and the predetermined unit can be constituted by an information signal of a certain information amount or less, and the substantial unit is formed according to the information amount of the input information signal. A transmission device having a configuration in which at least a part of an information signal can be arranged in the second area. The transmission device according to claim 10, wherein there are a plurality of types of information signals. One synchronous signal, a compressed information signal of a certain information unit and an uncompressed information signal of which the information amount of the certain information unit is not compressed are converted into error correction signals for every n units (n is a natural number of 1 or more). Are added to the signal to form one set of information units, the predetermined unit is N rows, and a first area where substantial information signals are arranged and M rows (M is a natural number of 1 or more) And a second area in which redundant signals are arranged, and the predetermined unit can be constituted by an information signal having a certain information amount or less, and the information amount of the input information signal is A transmission device having a configuration in which at least a part of the substantial information signal can be arranged in the second area in response. One synchronization signal and a compressed information signal in which the information amount of a certain information unit is compressed or an uncompressed information signal in which the information amount of a certain information unit is not compressed are divided into n units (n is a natural number of 1 or more) for every n units. An error correction signal is added to the signal to form one aggregate information unit, an identification code for identifying whether or not the information amount is a compressed signal is added, and the predetermined unit is N rows and the actual information is A first area in which signals are arranged, a second area in which M rows (M is a natural number of 1 or more) and redundant signals are arranged, and the predetermined unit is information having a predetermined information amount or less. A transmission device, which can be configured by a signal, wherein at least a part of the substantial information signal can be arranged in the second area according to the information amount of the input information signal. One set of one synchronizing signal, a compressed information signal of a certain information unit and an uncompressed information signal of a certain information unit whose amount of information is not compressed, one set for every n units (n is a natural number of 1 or more) In addition to the information unit, the predetermined unit is N rows, a first area where substantial information signals are arranged, and M rows (M is a natural number of 1 or more) and redundant signals are arranged. A second area and the predetermined unit can be constituted by an information signal of a certain information amount or less, and at least the substantial information signal according to the information amount of the input information signal. A transmission device having a configuration in which a part can be arranged in the second area. One synchronization signal and a compressed information signal in which the information amount of a certain information unit is compressed or an uncompressed information signal in which the information amount of a certain information unit is not compressed are divided into n units (n is a natural number of 1 or more) for every n units. An identification code for identifying whether the information amount is a compressed signal is added as one set of information units, and the predetermined unit is N rows, and a first area in which a substantial information signal is arranged is provided. A second area in which M rows (M is a natural number of 1 or more) and redundant signals are arranged, and wherein the predetermined unit can be constituted by an information signal having a certain information amount or less; A transmitting device having a configuration in which at least a part of the substantial information signal can be arranged in the second area according to the information amount of the input information signal. 17. The transmission device according to claim 13, wherein the redundant signal is configured by a parity signal. One synchronous signal and a compressed information signal of a fixed information unit are added with an error correction signal every n units (n is a natural number of 1 or more), and the signal is transmitted as one aggregate information unit. In a case where one or more fixed information units are collected to form a predetermined unit, the predetermined unit is N rows, and a first area where a substantial information signal is arranged and M rows (M is A second area in which a redundant signal is arranged and the predetermined unit can be constituted by an information signal having a predetermined information amount or less. A transmission method in which at least a part of the substantial information signal can be arranged in the second area according to the information amount of the signal. One synchronization signal and a compressed information signal of a certain information unit are transmitted as one set information unit for every n units (n is a natural number of 1 or more), and one or more of the certain information units are collected. In the case where a predetermined unit is formed, the predetermined unit is N rows, a first area in which a substantial information signal is arranged, and M rows (M is a natural number of 1 or more) and redundant. A second area in which a signal is arranged, and the predetermined unit can be constituted by an information signal having a predetermined information amount or less, and the substantial unit is configured in accordance with the information amount of the input information signal. A transmission method in which at least a part of a simple information signal can be arranged in the second area. 20. The transmission method according to claim 18, wherein the information signal includes a plurality of types. One synchronous signal, a compressed information signal of a certain information unit and an uncompressed information signal of which the information amount of the certain information unit is not compressed are converted into error correction signals for every n units (n is a natural number of 1 or more). Are added to the signal to form one set of information units, the predetermined unit is N rows, and a first area where substantial information signals are arranged and M rows (M is a natural number of 1 or more) And a second area in which redundant signals are arranged, and the predetermined unit can be constituted by an information signal having a certain information amount or less, and the information amount of the input information signal is A transmission method in which at least a part of the substantial information signal can be arranged in the second area in response to the request. One synchronization signal and a compressed information signal in which the information amount of a certain information unit is compressed or an uncompressed information signal in which the information amount of a certain information unit is not compressed are divided into n units (n is a natural number of 1 or more) for every n units. An error correction signal is added to the signal to form one aggregate information unit, an identification code for identifying whether or not the information amount is a compressed signal is added, and the predetermined unit is N rows and the actual information is A first area in which signals are arranged, a second area in which M rows (M is a natural number of 1 or more) and redundant signals are arranged, and the predetermined unit is information having a predetermined information amount or less. A transmission method in which a signal can be configured, and at least a part of the substantial information signal can be arranged in the second area according to an information amount of the input information signal. One set of one synchronizing signal, a compressed information signal of a certain information unit and an uncompressed information signal of a certain information unit whose amount of information is not compressed, one set for every n units (n is a natural number of 1 or more) In addition to the information unit, the predetermined unit is N rows, a first area where substantial information signals are arranged, and M rows (M is a natural number of 1 or more) and redundant signals are arranged. A second area and the predetermined unit can be constituted by an information signal of a certain information amount or less, and at least the substantial information signal according to the information amount of the input information signal. A transmission method in which a part can be arranged in the second area. One synchronization signal and a compressed information signal in which the information amount of a certain information unit is compressed or an uncompressed information signal in which the information amount of a certain information unit is not compressed are divided into n units (n is a natural number of 1 or more) for every n units. An identification code for identifying whether the information amount is a compressed signal is added as one set of information units, and the predetermined unit is N rows, and a first area in which a substantial information signal is arranged is provided. A second area in which M rows (M is a natural number of 1 or more) and redundant signals are arranged, and wherein the predetermined unit can be constituted by an information signal having a certain information amount or less; A transmission method in which at least a part of the substantial information signal can be arranged in the second area according to the information amount of the input information signal. The transmission method according to any one of claims 21 to 24, wherein the redundant signal includes a parity signal. A synchronizing signal removing means for removing a synchronizing signal from a signal received by using one synchronizing signal and a plurality of units of compressed information signals as one collective information unit; In the case where a unit is formed, the predetermined unit is N rows, a first area where a substantial information signal is arranged, and M rows (M is a natural number of 1 or more), and a redundant signal is formed. A second area to be arranged, and wherein the predetermined unit can be constituted by an information signal having a predetermined information amount or less, wherein the predetermined unit is arranged in the second area among output signals of the synchronization signal removing means. YX conversion means having a configuration capable of rearranging the converted substantial information signal in the first area, and an error in each unit to which an error correction signal is added among output signals of the YX conversion means. E that performs signal error correction based on the correction signal Receiver including a C decoder, and a decompression means for decompressing the information signal compressed the output signals for each one unit of the ECC decoder. A synchronizing signal removing means for removing a synchronizing signal from a signal received by using one synchronizing signal and a plurality of units of compressed information signals as one collective information unit; In the case where a unit is formed, the predetermined unit is N rows, a first area where a substantial information signal is arranged, and M rows (M is a natural number of 1 or more), and a redundant signal is formed. A second area to be arranged, and wherein the predetermined unit can be constituted by an information signal having a predetermined information amount or less, wherein the predetermined unit is arranged in the second area among output signals of the synchronization signal removing means. YX conversion means having a configuration capable of rearranging the converted substantial information signal in the first area, and an error in each unit to which an error correction signal is added among output signals of the YX conversion means. E that performs signal error correction based on the correction signal A C decoder; a distribution unit that distributes an output signal of the ECC decoder according to a synthesized rule; and a decompression unit that decompresses, for each unit, an information signal whose information amount has been compressed among the output signals of the distribution unit. Receiving device. A synchronizing signal removing means for removing a synchronizing signal from a signal received by using one synchronizing signal and a plurality of units of compressed information signals as one collective information unit; In the case where a unit is formed, the predetermined unit is N rows, a first area where a substantial information signal is arranged, and M rows (M is a natural number of 1 or more), and a redundant signal is formed. A second area to be arranged, and wherein the predetermined unit can be constituted by an information signal having a predetermined information amount or less, wherein the predetermined unit is arranged in the second area among output signals of the synchronization signal removing means. YX conversion means having a configuration capable of rearranging the converted substantial information signal in the first area, and an error in each unit to which an error correction signal is added among output signals of the YX conversion means. E that performs signal error correction based on the correction signal A C decoder, distribution means for distributing an output signal of the ECC decoder in accordance with a synthesized rule, expansion means for expanding, on a unit-by-unit basis, an information signal of which information amount is compressed among output signals of the distribution means, A non-expansion means for outputting an information signal whose information amount is not compressed among output signals of the distribution means. A synchronizing signal removing means for removing a synchronizing signal from a signal received by using one synchronizing signal and a plurality of units of compressed information signals as one collective information unit; In the case where a unit is formed, the predetermined unit is N rows, a first area where a substantial information signal is arranged, and M rows (M is a natural number of 1 or more), and a redundant signal is formed. A second area to be arranged, and wherein the predetermined unit can be constituted by an information signal having a predetermined information amount or less, wherein the predetermined unit is arranged in the second area among output signals of the synchronization signal removing means. A Y-X converter configured to be capable of rearranging the extracted substantial information signal in the first area, and expanding a compressed information signal among output signals of the Y-X converter in units of one unit. A receiving device comprising: A synchronizing signal removing means for removing a synchronizing signal from a signal received by using one synchronizing signal and a plurality of units of compressed information signals as one collective information unit; In the case where a unit is formed, the predetermined unit is N rows, a first area where a substantial information signal is arranged, and M rows (M is a natural number of 1 or more), and a redundant signal is formed. A second area to be arranged, and wherein the predetermined unit can be constituted by an information signal having a predetermined information amount or less, wherein the predetermined unit is arranged in the second area among output signals of the synchronization signal removing means. A YX conversion unit configured to be able to rearrange the obtained substantial information signal in the first area, a distribution unit that distributes an output signal of the YX conversion unit according to a synthesized rule, The amount of information in the output signal of the Receiving device and a decompressing means for decompressing the information signal for each one unit. A synchronizing signal removing means for removing a synchronizing signal from a signal received by using one synchronizing signal and a plurality of units of compressed information signals as one collective information unit; In the case where a unit is formed, the predetermined unit is N rows, a first area where a substantial information signal is arranged, and M rows (M is a natural number of 1 or more), and a redundant signal is formed. A second area to be arranged, and wherein the predetermined unit can be constituted by an information signal having a predetermined information amount or less, wherein the predetermined unit is arranged in the second area among output signals of the synchronization signal removing means. A YX conversion unit configured to be able to rearrange the obtained substantial information signal in the first area, a distribution unit that distributes an output signal of the YX conversion unit according to a synthesized rule, The amount of information in the output signal of the Receiver including a decompressing means for decompressing each one unit of information signal, and a non-decompression means for outputting an information signal quantity information is not compressed the output signals of the distribution means. The receiving device according to any one of claims 26 to 31, wherein the redundant signal includes a parity signal. One synchronization signal and a plurality of information signals obtained by compressing a predetermined information unit are received as one set information unit, and one or more predetermined information units are collected to form a predetermined unit. In the case, the predetermined unit is N rows, a first area in which substantial information signals are arranged, and M rows (M is a natural number of 1 or more) and a second area in which redundant signals are arranged. And the predetermined unit can be composed of an information signal having a certain information amount or less, and a substantial information signal arranged in the second area can be rearranged in the first area. A receiving device having a configuration. The receiving device according to claim 33, wherein there are a plurality of types of information signals to be received. One synchronous signal, a plurality of information signals including a compressed information signal of a certain information unit in which the information amount is compressed and an uncompressed information signal of a certain information unit in which the information amount is not compressed are collected as one. Receiving one set of information units and collecting at least one of the certain information units to form a predetermined unit, wherein the predetermined unit is N rows and a substantial information signal is arranged. It has a first area and a second area having M rows (M is a natural number of 1 or more) and in which redundant signals are arranged, and the predetermined unit can be constituted by an information signal having a certain information amount or less. A receiving device having a configuration in which a substantial information signal arranged in the second area can be rearranged in the first area; The receiving device according to any one of claims 33 to 35, wherein the redundant signal includes a parity signal. One synchronization signal and a plurality of information signals obtained by compressing a predetermined information unit are received as one set information unit, and one or more predetermined information units are collected to form a predetermined unit. In the case, the predetermined unit is N rows, a first area in which substantial information signals are arranged, and M rows (M is a natural number of 1 or more) and a second area in which redundant signals are arranged. And the predetermined unit can be composed of an information signal having a certain information amount or less, and a substantial information signal arranged in the second area can be rearranged in the first area. The configured receiving method. The receiving method according to claim 37, wherein there are a plurality of types of information signals to be received. One synchronous signal, a plurality of information signals including a compressed information signal of a certain information unit in which the information amount is compressed and an uncompressed information signal of a certain information unit in which the information amount is not compressed are collected as one. Receiving one set of information units and collecting at least one of the certain information units to form a predetermined unit, wherein the predetermined unit is N rows and a substantial information signal is arranged. It has a first area and a second area having M rows (M is a natural number of 1 or more) and in which redundant signals are arranged, and the predetermined unit can be constituted by an information signal having a certain information amount or less. And a receiving method in which a substantial information signal arranged in the second area can be rearranged in the first area. The receiving method according to any one of claims 37 to 39, wherein the redundant signal is configured by a parity signal. A transmission / reception device comprising the transmission device according to any one of claims 1 to 17 and the reception device according to any one of claims 26 to 36. A transmission / reception method comprising the transmission method according to any one of claims 18 to 25 and the reception method according to any one of claims 37 to 40.

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