JPS619090A - Still picture transmission system - Google Patents
Still picture transmission systemInfo
- Publication number
- JPS619090A JPS619090A JP59130582A JP13058284A JPS619090A JP S619090 A JPS619090 A JP S619090A JP 59130582 A JP59130582 A JP 59130582A JP 13058284 A JP13058284 A JP 13058284A JP S619090 A JPS619090 A JP S619090A
- Authority
- JP
- Japan
- Prior art keywords
- line
- residual
- order
- value
- line buffer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N19/00—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
- H04N19/50—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding
- H04N19/593—Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving spatial prediction techniques
Abstract
Description
【発明の詳細な説明】
[技術分野]
本発明は濃淡画像を公衆電話回線などを利用して伝送す
る静止画像伝送方式に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a still image transmission system for transmitting grayscale images using public telephone lines or the like.
[背景技術1
一般に文字コードの伝送路は8ビット単位で構成される
が、コントロールフードを除くと7ビツトとなり、した
がって画像情報を伝送する場合に1画素のデータ(6〜
7ビツト)を3ビツトに圧縮できれば1文字に2画素の
データを伝送できる・が、通常行われる前値予測<Dp
c=)で非線形量子化された予測残差は、実用的な復元
画像を得るためにはどうしても4ビツト以上必要とされ
るので、1文字に1画素のデータしか乗せることができ
ず圧縮効果が低いという問題があった。[Background technology 1 Generally, character code transmission paths are configured in 8-bit units, but if the control hood is excluded, the number becomes 7 bits. Therefore, when transmitting image information, one pixel of data (6 to 6 bits) is used.
If 7 bits) can be compressed to 3 bits, it is possible to transmit 2 pixels of data per character.However, the previous value prediction <Dp
Since the prediction residual non-linearly quantized with c=) is required to have at least 4 bits in order to obtain a practical restored image, it is possible to carry only one pixel of data per character, which reduces the compression effect. The problem was that it was low.
本発明者等は特願昭59−s314e号において、階調
が6ビツトの画素データのうち上位4ビツトを圧縮符号
化して先に伝送し、残り2ビツトを後で伝送する方式を
提案し、圧縮符号化方式として前値予測DPCM方式、
前値予測残差のライン間の差をとる複合差分符号化方式
あるいは可変標本密度符号化方式を使用した。この方式
によれit、+:位4ビットの画像は3ビツト以下に圧
縮でトるので、1文字に2画素分を伝送することにより
必要最小限の情報が迅速に得られるという利点があるが
、画像情報を2回に分けて伝送するために全体の伝送文
字数が多くなるという欠点があった。In Japanese Patent Application No. 59-S314E, the present inventors proposed a method in which the upper 4 bits of pixel data with 6-bit gradation are compressed and encoded and transmitted first, and the remaining 2 bits are transmitted later. Previous value prediction DPCM method as compression encoding method,
A composite differential encoding method or a variable sampling density encoding method was used, which takes the difference between lines of the previous prediction residual. With this method, an image with 4 bits of it, +: can be compressed to 3 bits or less, so it has the advantage that the minimum necessary information can be quickly obtained by transmitting 2 pixels per character. However, since the image information is transmitted twice, the total number of characters to be transmitted increases.
[発明の目的1
本発明は上記の問題点に鑑み為されたものであり、通常
6〜8ビツトの階調が必要とされる画像情報を1画素当
り3ビツト以下に圧縮符号化できる静止画像伝送方式を
提供することを目的とするものである゛。[Objective of the Invention 1 The present invention has been made in view of the above problems, and provides a still image in which image information that normally requires 6 to 8 bits of gradation can be compressed and encoded to 3 bits or less per pixel. The purpose is to provide a transmission method.
[発明の開示1
本発明方式は、まず原画から水平方向(あるいは垂直方
向)の前値予測を行ない、その残差(1次残差)の1ラ
イン分をラインバッフ7に記憶させ、このラインバッフ
ァと次のラインの1次残差を用いて順次垂直方向(ある
いは水平方向)の前値予測を行ない、その残差(2次残
差)を圧縮符号化して伝送するものであり、1次残差パ
ターンに残っている走査方向と直角な方向の相関性を抽
出して2次残差の分布をゼロ付近に集中させることによ
り・ダ データの圧縮効率を高め、1画
素3ビツト以下の符号化を可能にしたものである。[Disclosure 1 of the Invention The method of the present invention first predicts the previous value in the horizontal direction (or vertical direction) from the original image, stores one line of the residual (primary residual) in the line buffer 7, and The previous value prediction in the vertical direction (or horizontal direction) is performed sequentially using the buffer and the first-order residual of the next line, and the residual (secondary residual) is compressed and encoded and transmitted. By extracting the correlation in the direction perpendicular to the scanning direction that remains in the residual pattern and concentrating the distribution of secondary residuals around zero, data compression efficiency can be improved, and codes of 3 bits or less per pixel can be compressed. This is what made it possible.
第1図は本発明方式を実施する装置の1例を示したもの
である。同図において、モノクロカメラ1から出力され
るフンポジットビデオ信号は同期分離回路2で同期信号
を分離されたのち、A/Dフンバータ3でディジタル化
され、データセレクタ4によりフレームメモリ5に記憶
される。このデータは自動的にマイクロフンピユータ6
によって圧縮符号化され、モデム7を介して公衆電話器
・線に送り出される。本装置はたとえば店舗
と住宅との間で相互に異常を監視する保安システムなど
に用いられるもので、受信側では同図と同様な装置を使
用してD/Aフンバータ8および合成回路9により画像
の復元を行ない、モニタTVIOに表示する。11はモ
ード切換回路である。フレームメモリ5は1画面分、す
なわち256X2S6画素、8ビット階調の場合は64
にバイトで構成され、A/D、D/A変換も含めて1画
素当り200nSecT読み書外を行う。CPUにはイ
ンチ″°0°iZl、−i”f4o7Z8000”((
51!JfH、アれる。FIG. 1 shows an example of a device implementing the method of the present invention. In the same figure, a sync signal is separated from a sync signal output from a monochrome camera 1 by a sync separator 2, digitized by an A/D converter 3, and stored in a frame memory 5 by a data selector 4. . This data is automatically transferred to the microcomputer 6.
It is compressed and encoded by the modem 7 and sent to the public telephone line. This device is used, for example, in a security system that mutually monitors abnormalities between a store and a residence.On the receiving side, a device similar to the one shown in the figure is used to transmit an image using a D/A frequency converter 8 and a synthesis circuit 9. is restored and displayed on the TVIO monitor. 11 is a mode switching circuit. Frame memory 5 is for one screen, that is, 256 x 2 S 6 pixels, 64 pixels for 8-bit gradation
It consists of bytes, and reads and writes 200nSecT per pixel, including A/D and D/A conversion. The CPU has inches ″°0°iZl, -i″f4o7Z8000″((
51! JfH, it's possible.
第2図は第1図の装置による送信および受信の処理手順
をブロック図で示したものである。送信側において、イ
が1次の前値予測回路、口が2次の前値予測回路であり
、水平走査を行なっている場合には1*残差の水平1ラ
イン分が2次の前値予測回路のラインバッファに記憶さ
れ、次の1ラインの1次残差との間で垂直方向の前値予
測を行ない、その残差信号を圧縮して伝送する。受信側
では、2次前値予測回路ハに水平1ライン分の2次残差
を記憶するラインバッファが設けられており、このライ
ンバッフ7を用いて次の1ラインとの間で1次残差が復
元され、さらに1次前値予測回路二で1次残差から原画
が復元される。1次の前値予測においては、前値の予測
値の0.97.5倍程度を現在の予測値としてそれに対
する残差を符号化しており、2次の前値予測では同様に
前ラインの予測値の0.977倍程度を現在の予測値と
している。一方2次元の線形予測である平面予測方式で
は、前値の予測値の0 、379倍と前ラインの予測値
の0.617倍を加えたものを現在の予測値としている
。次頁の表1は1次の前値予測残差、2次の前値予測残
差および平面子測残差表1
の例を、4ビット符号化(15区分)と3ビット符号化
(7区分)の場合について示したものである。FIG. 2 is a block diagram showing the processing procedure for transmission and reception by the apparatus shown in FIG. On the transmitting side, A is the first-order previous value prediction circuit, and A is the second-order previous value prediction circuit, and when horizontal scanning is performed, one horizontal line of 1*residual is the second-order previous value prediction circuit. This signal is stored in the line buffer of the prediction circuit, performs vertical previous value prediction between it and the primary residual of the next line, and compresses and transmits the residual signal. On the receiving side, the secondary previous value prediction circuit C is provided with a line buffer that stores the secondary residual for one horizontal line. The difference is restored, and a primary previous value prediction circuit 2 restores the original image from the primary residual. In the first-order previous value prediction, about 0.97.5 times the predicted value of the previous value is used as the current predicted value, and the residual error is encoded, and in the second-order previous value prediction, the previous line's predicted value is similarly The current predicted value is about 0.977 times the predicted value. On the other hand, in the plane prediction method, which is two-dimensional linear prediction, the current predicted value is the sum of 0.379 times the predicted value of the previous value and 0.617 times the predicted value of the previous line. Table 1 on the next page shows examples of first-order prior value prediction residuals, second-order prior value prediction residuals, and planar measurement residuals Table 1 for 4-bit encoding (15 categories) and 3-bit encoding (7 This shows the case of (category).
これを見れば、1次残差は分布の中心がプラス側に片寄
っているのに対して、2次残差はゼロを中心に分布して
おり、しかも平面予測残差と比べると2次残差のほうが
はるかにゼロへの集中度が高いことが示されている。こ
れは平面予測が単に2次元の予測であるのに対し、2次
前値予測では予測を2重に行なうので予測係数が高く相
関性を除く効果が大きいためである。If you look at this, you can see that the center of the distribution of the first-order residuals is biased toward the positive side, whereas the second-order residuals are distributed around zero, and compared to the planar prediction residuals, the second-order residuals are It is shown that the difference is much more concentrated towards zero. This is because, while plane prediction is simply a two-dimensional prediction, in quadratic previous value prediction, prediction is performed twice, so the prediction coefficient is high and the effect of removing correlation is great.
第3図(a)の実施例は第2図の2次前値予測回路口に
おける圧縮符号化を可変標本化密度符号化方式で行なっ
たものであり、予測ループ内に可変標本化密度の圧縮回
路と伸張回路を設けたら・のである。同図(1,)のハ
はその場合の受信側における可変標本化密度予測複合化
回路である。第4図はえ 可変標本化密
度符号北方・式の1例を図解したもので、標本化の周期
と標本値との関係を三角形で規定し、この三角形を図示
のように移動させて矢印で示した差分を伝送することに
より、受信側ではこの差分値と三角形とから標本化間隔
が求まり原波形が復元される。標本値の変動が小さい程
標本化間隔が伸びデータが圧縮されるようになっている
。In the embodiment shown in FIG. 3(a), the compression coding at the entrance of the secondary previous value prediction circuit shown in FIG. After installing a circuit and an expansion circuit... C in the figure (1,) is a variable sampling density prediction/complexing circuit on the receiving side in that case. Figure 4 Flies This is an illustration of an example of the variable sampling density code Kitakata formula, where the relationship between the sampling period and the sample value is defined by a triangle, and the triangle is moved as shown in the diagram and indicated by the arrow. By transmitting the indicated difference, the receiving side determines the sampling interval from this difference value and the triangle, and restores the original waveform. The smaller the variation in sample values, the longer the sampling interval becomes and the more compressed the data becomes.
[発明の効果]
上述のように本発明においては、原画から水平方向(あ
るいは垂直方向)の前値予測を行ない、得られた1次残
差の1ライン分をラインバッファに記憶させ、このライ
ンバッフ7と次のラインの1次残差を用いて順次垂直方
向(あるいは水平方向)の前値予測を行ない、こうして
得られた2次残差を圧縮符号化して伝送するものである
から、1次残差パターンに強く残っている走査方向と直
角な方向の相関性を抽出して2次残差の分布をゼロ付近
に集中さぜることにより伝送データの圧縮効率を高める
ことができ、そのために3ビツトの非線形量子化を用い
ても画質が良く、1文字中−に2画8ケ。アー、□6ユ
ゎ7.□1゜、1.カフ ずストを著しく低減し
得るという利点がある。[Effects of the Invention] As described above, in the present invention, a previous value is predicted in the horizontal direction (or vertical direction) from the original image, one line of the obtained primary residual is stored in a line buffer, and this line is The previous value prediction in the vertical direction (or horizontal direction) is performed sequentially using buffer 7 and the first-order residual of the next line, and the second-order residual thus obtained is compressed and encoded and transmitted. By extracting the strong correlation in the direction perpendicular to the scanning direction that remains in the secondary residual pattern and concentrating the distribution of secondary residuals around zero, it is possible to improve the compression efficiency of the transmitted data. Even when using 3-bit nonlinear quantization, the image quality is good, with 8 double strokes per character. Ah, □6yuゎ7. □1°, 1. It has the advantage of significantly reducing cuff strain.
第1図は本発明の一実施例を示すブロック回路図、第2
図は同上の要部のブロック回路図、第3図(、)(b)
は他の実施例を示す要部ブロック回路図、第4図は同上
の動作を示す説明図である。
1はモノクロカメラ、2は同期分離回路、3はl\/D
コンバータ、4はデータセレクタ、5はフレームメモリ
、6はマイクロプロセッサ、7はモデム、8はD/Aフ
ンバータ、9は合成回路、10はモニタT V、11は
モード切換回路。
代理人 弁理士 石 n] 艮 七
手続補正書(自発)
昭和59年10月8日
2、発 明の名称
静止画像伝送方式
3、補正をする者
事件との関係 特許出願人
任 所 大阪府門真市大字門真1048番地名 称
(583)松下電工株式会社
代表者小 林 郁
4、代理人
電話大阪(06)345−7777(代表〕第3図を別
紙の通り訂正する。FIG. 1 is a block circuit diagram showing one embodiment of the present invention, and FIG.
The figure is a block circuit diagram of the main part of the same as above, Figure 3(,)(b)
4 is a main block circuit diagram showing another embodiment, and FIG. 4 is an explanatory diagram showing the operation of the same. 1 is a monochrome camera, 2 is a synchronization separation circuit, 3 is l\/D
Converter, 4 is a data selector, 5 is a frame memory, 6 is a microprocessor, 7 is a modem, 8 is a D/A converter, 9 is a synthesis circuit, 10 is a monitor TV, and 11 is a mode switching circuit. Agent Patent Attorney Ishi n] Ai 7 Procedural Amendment (Spontaneous) October 8, 1982 2 Name of the invention Still image transmission method 3 Relationship with the case of the person making the amendment Appointment of patent applicant Office Kadoma, Osaka Prefecture Address: 1048 Kadoma, Ichi-Oza Name: (583) Matsushita Electric Works Co., Ltd. Representative: Iku Kobayashi 4, Agent: Osaka (06) 345-7777 (Representative) Figure 3 has been corrected as shown in the attached sheet.
Claims (1)
測を行ない、その残差(以下1次残差という)の1ライ
ン分をラインバッファに記憶させ、このラインバッファ
と次のラインの1次残差を用いて順次垂直方向(あるい
は水平方向)の前値予測を行ない、その残差(以下2次
残差という)を圧縮符号化して伝送することを特徴とす
る静止画像伝送方式。(1) Perform horizontal (or vertical) previous value prediction from the original image, store one line of the residual (hereinafter referred to as primary residual) in a line buffer, and store this line buffer and one line of the next line. A still image transmission system characterized by sequentially performing vertical (or horizontal) previous value prediction using second-order residuals, and compressing and encoding the residuals (hereinafter referred to as second-order residuals) before transmitting them.
Priority Applications (9)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP59130582A JPS619090A (en) | 1984-06-25 | 1984-06-25 | Still picture transmission system |
SE8501891A SE465347B (en) | 1984-04-25 | 1985-04-17 | PICTURE TRANSMISSION SYSTEM FOR SAMPLING AND COMPRESSING PICTURE DATA IN A TV PICTURE FIELD |
GB08509925A GB2158673B (en) | 1984-04-25 | 1985-04-18 | Picture transmission system |
CA000479755A CA1253958A (en) | 1984-04-25 | 1985-04-22 | Picture transmission system |
US06/726,717 US4703348A (en) | 1984-04-25 | 1985-04-24 | Picture transmission system using secondary differential variable sampling rate coding |
IT20464/85A IT1184231B (en) | 1984-04-25 | 1985-04-24 | IMAGE TRANSMISSION PROCEDURE |
DE19853514916 DE3514916A1 (en) | 1984-04-25 | 1985-04-25 | IMAGE TRANSFER SYSTEM |
FR8506342A FR2569074A1 (en) | 1984-04-25 | 1985-04-25 | METHOD AND SYSTEM FOR IMAGE TRANSMISSION |
US07/106,079 US4843465A (en) | 1984-04-25 | 1987-10-07 | Picture transmission system using secondary differential variable sampling rate coding |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP59130582A JPS619090A (en) | 1984-06-25 | 1984-06-25 | Still picture transmission system |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS619090A true JPS619090A (en) | 1986-01-16 |
Family
ID=15037657
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP59130582A Pending JPS619090A (en) | 1984-04-25 | 1984-06-25 | Still picture transmission system |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS619090A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62269581A (en) * | 1986-05-19 | 1987-11-24 | Matsushita Electric Ind Co Ltd | Electronic still camera |
JPS647715A (en) * | 1987-06-30 | 1989-01-11 | Canon Kk | Image data coder |
JP2012142886A (en) * | 2011-01-06 | 2012-07-26 | Kddi Corp | Image coding device and image decoding device |
-
1984
- 1984-06-25 JP JP59130582A patent/JPS619090A/en active Pending
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62269581A (en) * | 1986-05-19 | 1987-11-24 | Matsushita Electric Ind Co Ltd | Electronic still camera |
JPS647715A (en) * | 1987-06-30 | 1989-01-11 | Canon Kk | Image data coder |
JP2012142886A (en) * | 2011-01-06 | 2012-07-26 | Kddi Corp | Image coding device and image decoding device |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4764805A (en) | Image transmission system with line averaging preview mode using two-pass block-edge interpolation | |
EP0508351B1 (en) | Method and apparatus for the motion compensated predictive coding of an image signal | |
KR100292475B1 (en) | Device for compensating digital image shake | |
JPH0662387A (en) | Method and apparatus for spatial filtering of digital image decoded by block conversion | |
WO1988010051A1 (en) | Image transmission system with preview mode | |
CN1127055A (en) | Method and apparatus for providing scaleable compressed video signal | |
CN1064506C (en) | Method and apparatus for recovering an image in a video telephone system | |
US5691767A (en) | Video conferencing system with high resolution still image capability | |
JPH06125533A (en) | Error correction code additional device and error correcting device | |
JPS619090A (en) | Still picture transmission system | |
JPH06133284A (en) | Encoder and decoder | |
Monro et al. | Low bit rate colour fractal video | |
JPS619091A (en) | Still picture transmission system | |
JP2800269B2 (en) | Image signal encoding / decoding device and encoding device | |
JP2603274B2 (en) | Encoding device | |
JPH0220197B2 (en) | ||
JPH0690441A (en) | Optimum frame rate determining method | |
KR0125121B1 (en) | Apparatus for encoding the moving picture | |
JPS60227582A (en) | Still picture transmission system | |
JPS62266989A (en) | Highly efficient encoder | |
JPS61296864A (en) | Image transmission system | |
JPH0678305A (en) | Composite information transmitter | |
JPS61216583A (en) | Transmitting picture monitor system | |
CN117135315A (en) | Video data processing method and system | |
JPH0759112A (en) | Picture transmitter |