JPS6225318B2 - - Google Patents
Info
- Publication number
- JPS6225318B2 JPS6225318B2 JP55028942A JP2894280A JPS6225318B2 JP S6225318 B2 JPS6225318 B2 JP S6225318B2 JP 55028942 A JP55028942 A JP 55028942A JP 2894280 A JP2894280 A JP 2894280A JP S6225318 B2 JPS6225318 B2 JP S6225318B2
- Authority
- JP
- Japan
- Prior art keywords
- color difference
- signal
- color
- nonlinear transmission
- difference signal
- 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.)
- Expired
Links
- 230000005540 biological transmission Effects 0.000 claims description 13
- 238000010586 diagram Methods 0.000 description 14
- 230000000694 effects Effects 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/77—Circuits for processing the brightness signal and the chrominance signal relative to each other, e.g. adjusting the phase of the brightness signal relative to the colour signal, correcting differential gain or differential phase
Landscapes
- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Processing Of Color Television Signals (AREA)
Description
【発明の詳細な説明】
本発明は、カラーテレビジヨン画像の色の付い
た画像部分の画質を改善する装置に関するもの
で、特に色付部分の細かい画像を良好に再現する
ことのできる装置を提供しようとするものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for improving the image quality of colored image parts of color television images, and in particular provides an apparatus that can satisfactorily reproduce fine images of colored parts. This is what I am trying to do.
第１図は従来のカラーテレビジヨン受像機の一
部をブロツク図で表わしたものである。同図にお
いて、VIF信号（映像中間周波数信号）は映像検
波器１で検波され、輝度信号増幅器２および帯域
増幅器３に供給される。帯域増幅器３は複合カラ
ー映像信号に含まれる搬送色信号を取り出して増
幅し、３つの色差信号復調器４，５，６に供給す
る。 FIG. 1 is a block diagram showing a portion of a conventional color television receiver. In the figure, a VIF signal (video intermediate frequency signal) is detected by a video detector 1 and supplied to a luminance signal amplifier 2 and a band amplifier 3. The band amplifier 3 takes out the carrier color signal included in the composite color video signal, amplifies it, and supplies it to three color difference signal demodulators 4, 5, and 6.
上記色差信号復調器４，５，６は搬送色信号を
復調して３種類の色差信号（Ｒ―Ｙ），（Ｇ―
Ｙ），（Ｂ―Ｙ）を得、それらを３つの加算器７，
８，９に供給する。上記加算器７，８，９は、そ
れぞれに供給された色差信号と、輝度信号増幅器
２より伝送された輝度信号とを加算することによ
り３種の原色信号を作り、それらを受像管１０に
供給する。 The color difference signal demodulators 4, 5, and 6 demodulate the carrier color signal to generate three types of color difference signals (RY), (G-
Y), (BY) and add them to three adders 7,
Supply to 8 and 9. The adders 7, 8, and 9 create three types of primary color signals by adding the color difference signals supplied to each of them and the luminance signal transmitted from the luminance signal amplifier 2, and supply them to the picture tube 10. do.
以上に述べた様な従来のカラーテレビジヨン受
像機では、色差信号（例えば色差信号復調器４の
出力）の帯域幅は輝度信号増幅器２より伝送され
る輝度信号の帯域幅よりかなり狭い。例えば通常
のNTSC方式のカラーテレビジヨン受像機では、
輝度信号はＯHz〜3MHzの周波数成分を含んでい
るのに対し、色差信号は高々500KHzまでの周波
数成分までしか含んでいない。従つて、色の付い
た画像部分は狭帯域の色差信号が主として画像を
構成するので、鮮鋭度の低いぼけた画像になつて
しまう。 In the conventional color television receiver as described above, the bandwidth of the color difference signal (for example, the output of the color difference signal demodulator 4) is considerably narrower than the bandwidth of the brightness signal transmitted from the brightness signal amplifier 2. For example, in a normal NTSC color television receiver,
While the luminance signal includes frequency components of 0Hz to 3MHz, the color difference signal only includes frequency components of up to 500KHz. Therefore, since the colored image portion is mainly composed of narrow band color difference signals, the image becomes a blurred image with low sharpness.
そこで本発明では、従来にあつた上記のような
欠点をなくするため、色差信号の強度に応じて積
極的に輝度信号の高周波成分を混入させることに
より着色画像部分の解像度を改善するものであ
り、特に輝度信号の高周波成分抽出手段に特色を
有するものである。 Therefore, in the present invention, in order to eliminate the above-mentioned drawbacks of the conventional technology, the resolution of the colored image portion is improved by actively mixing the high frequency component of the luminance signal according to the intensity of the color difference signal. , in particular, the high frequency component extraction means of the luminance signal.
以下、第２図〜第８図を参照して詳細に説明す
る。 A detailed explanation will be given below with reference to FIGS. 2 to 8.
第２図は本発明の一実施例の構成を表わすブロ
ツク図である。色差信号源１１は色差信号を発生
するものであつて、例えば第１図の色差信号復調
器４〜６と同様のものである。輝度信号源１２は
輝度信号を発生するものであり、例えば第１図の
輝度信号増幅器２とする。色解像度補正回路１３
は本装置の特徴とする部分であり、輝度信号源１
２からの輝度信号Y′と色差信号源１１からの色
差信号（C′―Y′）を入力し、補正された色差信
号（C″―Y″）を出力して加算器１５に供給す
る。遅延回路１４は輝度信号Y′を遅延し色差信
号（C′―Y′）と時間を一致させる通常のテレビ
ジヨン受像機に具備されるものである。加算器１
５は輝度信号Y′と補正された色差信号（C″―
Y″）を加算しCRT等の表示装置１６に供給す
る。この加算器は上記の２信号を実質的に合成す
るものであればよい。 FIG. 2 is a block diagram showing the configuration of one embodiment of the present invention. The color difference signal source 11 generates color difference signals, and is similar to the color difference signal demodulators 4 to 6 in FIG. 1, for example. The luminance signal source 12 generates a luminance signal, and is, for example, the luminance signal amplifier 2 shown in FIG. Color resolution correction circuit 13
is the characteristic part of this device, and the luminance signal source 1
The luminance signal Y' from 2 and the color difference signal (C'-Y') from the color difference signal source 11 are input, and the corrected color difference signal (C''-Y'') is output and supplied to the adder 15. The delay circuit 14 is included in a normal television receiver and delays the luminance signal Y' to match the time with the color difference signal (C'-Y'). Adder 1
5 is the luminance signal Y′ and the corrected color difference signal (C″-
Y'') and supplies it to a display device 16 such as a CRT.This adder may be of any type as long as it substantially combines the above two signals.
第３図に第２図中の色解像度補正回路１３の部
分の詳細を示す。入力された輝度信号Y′は帯域
通過フイルター１７により高周波成分Y′Hのみが
抽出される。この高周波成分Y′Hの振幅・位相特
性は重要である。その理由は、１、色差信号
（C′―Y′）と乗算された後に色差信号に付加され
るものである、２、前述のように輝度信号Y′と
色差信号（C′―Y′）には時間の差があり乗算器
Ｅの時点で両者の時間が一致する必要があるから
である。 FIG. 3 shows details of the color resolution correction circuit 13 in FIG. 2. From the input luminance signal Y', only the high frequency component Y'H is extracted by the bandpass filter 17. The amplitude and phase characteristics of this high frequency component Y′ H are important. The reasons are: 1. It is added to the chrominance signal after being multiplied by the chrominance signal (C'-Y'); 2. As mentioned above, the luminance signal Y' and the chrominance signal (C'-Y') This is because there is a time difference between them, and the times of both must match at the time of multiplier E.
さて、この輝度信号の高周波成分Y′Hは第１の
非線形伝送回路１８に加えられ、出力信号Y′HN
は可変利得増幅器１９で振幅制御され、その後乗
算器２０に入力される。 Now, the high frequency component Y'H of this luminance signal is added to the first nonlinear transmission circuit 18, and the output signal Y'HN
is amplitude-controlled by a variable gain amplifier 19 and then input to a multiplier 20.
一方、色差信号（C′―Y′）は第２の非線形伝
送回路２１に加えられて出力信号（C′―Y′）Nと
なされ、乗算器２０に入力される。 On the other hand, the color difference signal (C'-Y') is applied to the second nonlinear transmission circuit 21 to form an output signal (C'-Y') N , which is input to the multiplier 20.
乗算器２０の出力信号（C″―Y″）HはY′HNCと
（C′―Y′）Nの積であり、加算器２２で元の色差信
号（C′―Y′）と加算される。従つて、加算器２
２の出力信号は補正された色差信号（C″―Y″）
となる。 The output signal (C″-Y″) H of the multiplier 20 is the product of Y′ HNC and (C′-Y′) N , and is added to the original color difference signal (C′-Y′) in the adder 22. Ru. Therefore, adder 2
The output signal of 2 is the corrected color difference signal (C″-Y″)
becomes.
第４図にこれら各信号の周波数帯域を示す。
Y′は元の輝度信号であり、ドツト妨害除去の為
クロマキヤリアの3.58MHzのところでは充分に減
衰されている。（C′―Y′）は元の色差信号の帯域
を示し、前述のように現行のカラーテレビジヨン
受像機においては、高々500KHzまでである。一
方、高周波成分Y′Hはこの色差信号中の失なわれ
た帯域を補うために図示実線のような帯域である
ことが望ましい。しかしながら、種々の制約が存
在する。一つは高域の付加によるクロスカラー防
害の増加を押さえる為に第４図中に点線で図示し
たような高域の制限を設ける必要があることであ
る。 FIG. 4 shows the frequency bands of these signals.
Y' is the original luminance signal, which is sufficiently attenuated at the chroma carrier's 3.58MHz to remove dot interference. (C'-Y') indicates the band of the original color difference signal, and as mentioned above, in current color television receivers, it is up to 500 KHz at most. On the other hand, it is desirable that the high frequency component Y'H has a band as shown by the solid line in the figure in order to compensate for the lost band in the color difference signal. However, various restrictions exist. One is that in order to suppress the increase in cross-color damage prevention due to the addition of high frequencies, it is necessary to limit the high frequencies as shown by the dotted line in FIG.
第５図は各信号の波形の一例である。ａ，ｂ，
ｃ，ｄはそれぞれY′，（C′―Y′），Y′H，（C″―
Y″）の波形の一例であり、Y′Hの低域側の帯域を
広くとると波形の幅は広くなり補正幅が広くな
る。ゆえにあまりに低域側を広くとることも制約
がある。 FIG. 5 shows an example of the waveform of each signal. a, b,
c and d are Y′, (C′−Y′), Y′ H , (C″−
This is an example of the waveform of Y''), and if the lower band of Y'H is widened, the width of the waveform becomes wider and the correction width becomes wider.Therefore, there is also a restriction in making the lower band too wide.
さらに第三の制約として前述の時間の一致の問
題がある。本装置においては、第６，７図に示す
ように２つの単位遅延素子T1，T2と、振幅を1/2
にする回路A1，A2と合成回路Ｓを備えたトラン
スバーサルフイルターを帯域通過フイルター１７
として用いることにより解決できた。第６図はそ
の原理図、第７図は実際の具体回路図である。Z0
は遅延素子T1，T2の特性インピーダンスであ
る。第８図ａはそのフイルター全体の振幅・位相
の周波数特性である。 Furthermore, the third constraint is the above-mentioned problem of time matching. In this device, as shown in Figs. 6 and 7, two unit delay elements T 1 and T 2 and an amplitude of 1/2 are used.
A transversal filter equipped with circuits A 1 and A 2 and a synthesis circuit S is connected to a band pass filter 17.
I was able to solve the problem by using it as FIG. 6 is a principle diagram thereof, and FIG. 7 is an actual specific circuit diagram. Z 0
is the characteristic impedance of delay elements T 1 and T 2 . FIG. 8a shows the amplitude and phase frequency characteristics of the entire filter.
図において本フイルターの伝達関数Ｈ（Z-1）
は、
であり、
a0＝１／２，a1＝−１，a2＝１／２
であるから、
Ｈ（Z-1）＝１／２（１−Z-1）2
となる。これを周波数領域に変換すると、
｜Ｈ（ω）｜＝2sin2π／ｃ
（ただしｃ＝１／Ｔ）
∠Ｈ（ω）＝ωＴ
となり第８図ｂに示すようになる。いま、単位遅
延素子T1，T2の遅延時間をともにＴ＝0.2μｓと
ｃ／２＝2.5MHzとなる。また群遅延ｄＨ（ω）／ｄω
＝
Ｔとなり一定となり、Y′Hの低域側の立ち上がり
特性は本フイルターで決定し得る。一方、高域側
は上述の制約により3.58MHzを減衰点とする高域
減衰フイルターを別に設けることにより別個に決
定し得る。また時間制約はY′Hの後信号処理回路
すなわち非線形伝送回路１８及び可変利得増幅器
１９の処理時間を見込んでも、Ｔ＝0.2μｓであ
れば通常の輝度信号Ｙと色差信号（C′―Y′）の
時間差0.5〜0.7μｓに充分対応するものとなる。 In the figure, the transfer function H (Z -1 ) of this filter is
teeth, Since a 0 = 1/2, a 1 = -1, and a 2 = 1/2, H(Z -1 ) = 1/2 (1 - Z -1 ) 2 . When this is converted into the frequency domain, |H(ω)|=2sin 2 π/c (where c=1/T) ∠H(ω)=ωT, as shown in FIG. 8b. Now, the delay times of unit delay elements T 1 and T 2 are both T=0.2 μs and c/2=2.5 MHz. Also, the group delay dH(ω)/dω
= T, which is constant, and the rising characteristics of the low frequency side of Y'H can be determined by this filter. On the other hand, the high frequency side can be determined separately by separately providing a high frequency attenuation filter with an attenuation point of 3.58 MHz due to the above-mentioned restrictions. Furthermore, even if the processing time of the post- Y′H signal processing circuit, that is, the nonlinear transmission circuit 18 and the variable gain amplifier 19 is taken into account, if T=0.2 μs, the normal luminance signal Y and the color difference signal (C′−Y′ ) can sufficiently correspond to the time difference of 0.5 to 0.7 μs.
非線形伝送回路１８の特性は第３図のブロツク
図中に示すものであるが、この特性は、入力信号
が零近辺の不感帯を有していわゆるベースクリツ
プ特性を持ち、また、負入力に対して出力が微少
な一定値となることの２点を特徴とし、それぞれ
ノイズ除去効果及び色差信号を減少する方向のみ
の補正効果を生じる。 The characteristics of the nonlinear transmission circuit 18 are shown in the block diagram of FIG. The two characteristics are that the output is a small constant value, and each produces a noise removal effect and a correction effect only in the direction of reducing the color difference signal.
非線形伝送回路２１の特性は第３図のブロツク
図中に示すものであるが、この特性は、（R′―
Y′）入力に対しては利得が低く、負の入力に対
して出力が零か微少になることの２点を特徴と
し、それぞれ（R′―Y′）入力に対して過補正に
ならないこと及び負の色差入力に対して補正しな
いことになる。 The characteristics of the nonlinear transmission circuit 21 are shown in the block diagram of FIG.
It is characterized by two points: the gain is low for the Y') input, and the output is zero or very small for the negative input, and that it does not overcorrect for the (R'-Y') input. and negative color difference input will not be corrected.
以上の実施例から明らかなように、本発明によ
れば、帯域幅の狭い色差信号が広帯域の輝度信号
に重なつて着色画像部分の解像度を低下させれば
させる程大きな補正信号が発生し、解像度を改善
する。また通常の受像機に本発明になる回路を付
加することによつて、何ら他の回路を変更するこ
となく本機能を発揮させることができる。 As is clear from the above embodiments, according to the present invention, the more the narrow-band color difference signal overlaps the wide-band luminance signal and lowers the resolution of the colored image portion, the larger the correction signal is generated. Improve resolution. Furthermore, by adding the circuit according to the present invention to an ordinary receiver, this function can be achieved without changing any other circuits.
第１図は従来のカラーテレビジヨン受像機のブ
ロツク図、第２図は本発明の一実施例におけるカ
ラーテレビジヨン受像機の色解像度補正回路のブ
ロツク図、第３図はその要部のブロツク図、第４
図は本回路における各信号の周波数帯域を示す特
性図、第５図は本回路の原理を説明する波形図、
第６図および第７図は本回路に用いる帯域通過フ
イルターのブロツク図および回路図、第８図はそ
の特性図である。
１……映像検波器、２……輝度信号増幅器、３
……帯域増幅器、４，５，６……色差信号復調
器、７，８，９……加算器、１０……表示装置、
１１……色差信号源、１２……輝度信号源、１３
……色解像度補正回路、１４……遅延回路、１５
……加算器、１６……表示装置、１７……帯域通
過フイルター、１８……第１の非線形伝送回路、
１９……可変利得増幅器、２０……乗算器、２１
……第２の非線形伝送回路、２２……加算器。
Fig. 1 is a block diagram of a conventional color television receiver, Fig. 2 is a block diagram of a color resolution correction circuit of a color television receiver according to an embodiment of the present invention, and Fig. 3 is a block diagram of its essential parts. , 4th
The figure is a characteristic diagram showing the frequency bands of each signal in this circuit, and Figure 5 is a waveform diagram explaining the principle of this circuit.
6 and 7 are block diagrams and circuit diagrams of a bandpass filter used in this circuit, and FIG. 8 is a characteristic diagram thereof. 1... Video detector, 2... Luminance signal amplifier, 3
... Bandwidth amplifier, 4, 5, 6 ... Color difference signal demodulator, 7, 8, 9 ... Adder, 10 ... Display device,
11... Color difference signal source, 12... Luminance signal source, 13
...Color resolution correction circuit, 14...Delay circuit, 15
... adder, 16 ... display device, 17 ... bandpass filter, 18 ... first nonlinear transmission circuit,
19...variable gain amplifier, 20...multiplier, 21
...Second nonlinear transmission circuit, 22...Adder.
Claims (1)
れた２次のトランスバーサルフイルターを含む帯
域通過フイルターと、この帯域通過フイルターに
接続され非線形伝送特性を有する第１の非線形伝
送回路と、この非線形伝送回路に接続されコント
ロール電圧により利得が制御される可変利得増幅
器と、色差信号源に接続され非線形伝送特性を有
する第２の非線形伝送回路と、この第２の非線形
伝送回路と上記可変利得増幅器とに接続され両者
の出力を乗算する乗算器と、この乗算器と上記色
差信号源とに接続され、色差信号に補正を加える
加算器とを具備したことを特徴とするカラーテレ
ビジヨン受像機の色解像度補正回路。1. A bandpass filter connected to a luminance signal source and including a second-order transversal filter configured with two delay lines; a first nonlinear transmission circuit connected to the bandpass filter and having nonlinear transmission characteristics; a variable gain amplifier connected to the nonlinear transmission circuit and whose gain is controlled by a control voltage; a second nonlinear transmission circuit connected to the color difference signal source and having nonlinear transmission characteristics; and the second nonlinear transmission circuit and the variable gain amplifier. A color television receiver comprising: a multiplier connected to the multiplier for multiplying the outputs of both; and an adder connected to the multiplier and the color difference signal source for correcting the color difference signal. Color resolution correction circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2894280A JPS56125178A (en) | 1980-03-06 | 1980-03-06 | Chroma resolution correcting circuit for color television receiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2894280A JPS56125178A (en) | 1980-03-06 | 1980-03-06 | Chroma resolution correcting circuit for color television receiver |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56125178A JPS56125178A (en) | 1981-10-01 |
| JPS6225318B2 true JPS6225318B2 (en) | 1987-06-02 |
Family
ID=12262454
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2894280A Granted JPS56125178A (en) | 1980-03-06 | 1980-03-06 | Chroma resolution correcting circuit for color television receiver |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56125178A (en) |
-
1980
- 1980-03-06 JP JP2894280A patent/JPS56125178A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56125178A (en) | 1981-10-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| FI72416C (en) | REGLERBAR ICKE-LINJAER BEHANDLING AV VIDEOSIGNALER. | |
| JPS628994B2 (en) | ||
| JPS6133500B2 (en) | ||
| US4656502A (en) | Color mixing or interference reduction circuit in color TV decoding circuits | |
| US5561473A (en) | Contour correction signal generating circuit | |
| US4336552A (en) | Vertical aperture correction circuit | |
| US4748500A (en) | Device for correcting contours in an image and use of such a device in a color television camera | |
| JPH04271570A (en) | Contour correction circuit for image | |
| US4654709A (en) | Vertical contour correction device | |
| JPS6225318B2 (en) | ||
| JPS622506B2 (en) | ||
| JP2549737B2 (en) | Video signal processing circuit | |
| JP2871323B2 (en) | Video signal processing device | |
| JP2830587B2 (en) | Video signal processing device | |
| JP2698637B2 (en) | Luminance signal / chrominance signal separation circuit | |
| JPH03263977A (en) | Television receiver | |
| US3534151A (en) | Means for improving the color rendition in a pal color television system | |
| JPH05252421A (en) | Contour correcting device | |
| KR880000842B1 (en) | Comp filter apparatus | |
| JPH03120963A (en) | Contour correction device | |
| JPS6033357B2 (en) | Image quality improvement device for color television receivers | |
| JPH0345095A (en) | Picture contour exaggeration circuit | |
| JPS6219116B2 (en) | ||
| JPH01236890A (en) | Y/c separating circuit | |
| JPH0767178B2 (en) | Color noise reduction circuit |