JPS61193590A - Carrier chrominance signal processing circuit - Google Patents

Abstract

PURPOSE:To make the titled circuit easy to realize ICs by providing a means by which four low-pass carrier signals, being higher frequency than a horizontal scanning frequency and having different phases by 90 deg. each other, are selected and picked up in each one horizontal scanning period and a means by which the selected low-pass carrier signals are balance-modulated by means of two color-difference signals. CONSTITUTION:A signal fH outputted from a 160 multiplying circuit 2 is changed to a signal 80 by means of a flip-flop 13, and furthermore changed to the low- pass carrier signals a, -a of 40fH, while an output signal a of a flip-flop 14 is fed to a flip-flop 15 and changed to a low-pass carrier signals b, -b of 40fH. The low-pass carrier signals a, b, -a and -b have different phase shift of 90 deg. in this order respectively. On the other hand, the signal fH is changed to a signal fH/2 by means of a flip-flop 16 and furthermore changed to a control signal x of fH by means of flip-flop 17. The signal fH and the signal x are fed by means of a flip-flop 18 to be a control signal y of the fH. Thus the titled circuit can be constituted so as to carry out the phase shift of 90 deg. and phase shift each 1H and becomes easy to simplify a circuit comparing conventional circuit, resulting in the realization of ICs.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は搬送色信号処理回路に係り、２つの色差信号か
ら平衡変調により低域変換搬送色信号を得る回路に関す
る。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a carrier color signal processing circuit, and more particularly, to a circuit for obtaining a low-pass converted carrier color signal from two color difference signals by balanced modulation.

従来の技術 例えばテレビジョンカメラ一体形のＶＴＲにおける映像
信号処理は、例えばＮＴＳＣ方式では低域変換搬送色信
号周波数（例えば６２９ｋＨｚ　）の搬送波（以下、低
域搬送波という）をテレビジョンカメラ信号系からの色
差信号で平衡変調し、ＦＭ変調されたテレビジョンカメ
ラ信号系からの輝度信号に重畳して磁気テープに記録す
る。BACKGROUND OF THE INVENTION Video signal processing in, for example, a VTR integrated with a television camera is performed by converting a carrier wave (hereinafter referred to as a low-frequency carrier wave) of a low-frequency conversion carrier color signal frequency (for example, 629 kHz) from a television camera signal system in the NTSC system, for example. Balance modulation is performed using a color difference signal, and the signal is recorded on a magnetic tape by being superimposed on an FM-modulated luminance signal from a television camera signal system.

第７図は従来の映像信号処理回路の一例をＮＴＳＣ方式
に適用したブロック系統図を示す。同図において、テレ
ビジョンカメラ信号系回路１から取出された水平走査周
波数ｆＨは１ｏ０逓倍回路２にて信号１６０ｂ＋　（第
２図（Ａ）とされて移相回路３に供給される。移相回路
３からは１Ｈ毎に位相９０’進みの４ｏ　ｆＨの低域搬
送波ａ、ｂ、ａ。FIG. 7 shows a block system diagram in which an example of a conventional video signal processing circuit is applied to the NTSC system. In the figure, the horizontal scanning frequency fH taken out from the television camera signal system circuit 1 is converted into a signal 160b+ (FIG. 2 (A)) by the 1o0 multiplier circuit 2 and supplied to the phase shift circuit 3. From 3 onwards, 4o fH low frequency carrier waves a, b, a with a phase lead of 90' every 1H.

ｂ及び１Ｈ毎に位相９０１Ｍれの４ＯｆＨの低域搬送波
ａ、ｂ、ａ、ｂ　　（第２図（Ｃ）〜（Ｆ））が各フィ
ールド毎に交互に出力され、平衡変調器４及び９０”移
相器５に供給される。９０°移相器５にて９０°移相さ
れた低域搬送波は平衡変調器６に供給される。4OfH low-frequency carrier waves a, b, a, b (FIG. 2 (C) to (F)) with a phase difference of 901M every 1H are output alternately for each field, and the balanced modulators 4 and 90" It is supplied to a phase shifter 5. The low frequency carrier wave whose phase has been shifted by 90 degrees by the 90 degrees phase shifter 5 is supplied to a balanced modulator 6.

平衡変調器４．６において、低域搬送波はテレビジョン
カメラ信号系回路１からの色差信号（Ｒ−Ｙ）、（Ｂ−
Ｙ）にて直角２相平衡変調され、加算器７にて加算され
て低域変換搬送波信号とされる。一方、テレビジョンカ
メラ信号系回路１からの輝度信号Ｙは輝度信号記録処理
回路８にてＦＭ変調され、加算器９にて加算器７からの
低域変換搬送色信号と加算される。加算器９の出力は記
録アンプ１０にて増幅され、記録ヘッド１１にて磁気テ
ープ１２に記録される。In the balanced modulator 4.6, the low frequency carrier waves are the color difference signals (R-Y) and (B-) from the television camera signal system circuit 1.
The signals are subjected to quadrature two-phase balanced modulation at Y) and added at an adder 7 to form a low frequency converted carrier wave signal. On the other hand, the luminance signal Y from the television camera signal system circuit 1 is subjected to FM modulation in the luminance signal recording processing circuit 8, and is added to the low frequency conversion carrier color signal from the adder 7 in the adder 9. The output of the adder 9 is amplified by a recording amplifier 10 and recorded on a magnetic tape 12 by a recording head 11.

発明が解決しようとする問題点 従来回路は、移相回路３と９０°移相器５とは別々の回
路で構成されているため、回路が複雑であり、ＩＣ化し
にくい等の問題点があった。Problems to be Solved by the Invention In the conventional circuit, the phase shift circuit 3 and the 90° phase shifter 5 are configured as separate circuits, so the circuit is complicated and has problems such as being difficult to integrate into an IC. Ta.

本発明は、直角２相変調のための９０”移相と１日毎の
移相とを同一のロジック回路にて行なうように構成し、
回路を簡単にし得、ＩＣ化し易い搬送色信号処理回路を
提供することを目的とする。The present invention is configured to perform a 90" phase shift for quadrature two-phase modulation and a daily phase shift in the same logic circuit,
It is an object of the present invention to provide a carrier color signal processing circuit whose circuit can be simplified and which can be easily integrated into an IC.

問題点を解決するための手段 第１図中、１６０逓倍回路２、フリップフロップ１３〜
１５は水平走査周波数よりも高い周波数の互いに９０°
位相の異なる４つの低域搬送波信号を得る手段、フリッ
プ７０ツブ１６〜１８、スイッチ回路２０は、４つの低
域搬送波信号を１水平走査期間毎に選択して取出す手段
、平衡変調器４゜６は、選択された低域搬送波信号を２
つの色差信号で平衡変調する手段の各−実施例である。Means for solving the problem In Figure 1, 160 multiplier circuit 2, flip-flops 13-
15 are 90° to each other at frequencies higher than the horizontal scanning frequency.
Means for obtaining four low frequency carrier wave signals having different phases, flip 70 knobs 16 to 18, switch circuit 20, means for selecting and extracting four low frequency carrier wave signals for each horizontal scanning period, balanced modulator 4.6 converts the selected low-frequency carrier signal to 2
3A and 3B are examples of means for performing balanced modulation with two color difference signals;

作用 ４つの低域搬送波信号を得る手段、これらを１水平走査
期間毎に選択して取出す手段をロジック回路で構成する
。Function: The means for obtaining four low frequency carrier wave signals and the means for selecting and extracting them every horizontal scanning period are constituted by logic circuits.

実施例 第１図は本発明回路の一実施例のブロック系統図を示し
、同図中、第７図と同一部分には同一番号を付してその
説明を省略する。同図において、破線で包囲した回路は
ロジック回路であり、ＩＣにて構成されている。１６０
逓倍回路２からの信号１６０ｆ＋　（第２図（Ａ））は
フリップフロップ１３にて信号８０ｆ＋（同図（Ｂ））
とされ、更にフリップフロップ１４にて４０ｂ＋の低域
搬送波信号ａ、１（同図（Ｃ）、（Ｅ））とされる。信
号１６０ｆ＋及びフリップフロップ１４の出力信号ａは
フリップフロップ１５にて供給されて４０ｆ＋の低域搬
送波信号す、ｂ　　（同図（Ｄ）、（Ｆ））とされる。Embodiment FIG. 1 shows a block system diagram of an embodiment of the circuit of the present invention. In the figure, the same parts as in FIG. 7 are given the same numbers and their explanations will be omitted. In the figure, a circuit surrounded by a broken line is a logic circuit, and is constructed of an IC. 160
The signal 160f+ (FIG. 2 (A)) from the multiplier circuit 2 is converted into the signal 80f+ (FIG. 2 (B)) by the flip-flop 13.
Further, the flip-flop 14 generates a 40b+ low frequency carrier signal a, 1 ((C) and (E) in the same figure). The signal 160f+ and the output signal a of the flip-flop 14 are supplied to the flip-flop 15 and are converted into 40f+ low-frequency carrier signals S, b ((D) and (F) in the same figure).

低域搬送波信号ａ、ｂ、ａ、ｂはこの順に９０°移相が
異なった信号である。The low-frequency carrier signals a, b, a, and b are signals with different phase shifts of 90° in this order.

一方、信号ｆＨ（第３図（Ａ））はフリップフロップ１
６にて信号ｆＨ／２（同図（Ｂ））とされ、更にフリッ
プフロップ１７にてｆ＋／４の制御信号×　（同図（Ｃ
））とされる。信号ｆＨ及び信号Ｘはフリップフロップ
１８にて供給されてｆＨ／４の制御信号Ｖ　（同図（Ｄ
））とされる。On the other hand, the signal fH (FIG. 3(A)) is applied to the flip-flop 1.
6, the signal fH/2 ((B) in the same figure) is generated, and the flip-flop 17 converts the control signal of f+/4 ((C)
)). The signal fH and the signal
)).

制御信号ｘ、ｙは９０°位相の異なった信号である。The control signals x and y are signals with a 90° phase difference.

低域搬送波信号ａ、ｂ、ａ、ｂ、制御信号Ｘ。Low frequency carrier signals a, b, a, b, control signal X.

ｙ１ドラムパルス発生器１９からの１フイールド毎にレ
ベル変化するドラムパルスｄ　　（ＮＴＳＣ方式では３
０Ｈｚ　、ＰＡＬ方式では２５Ｈｚ＞はスイッチ回路２
０に供給される。スイッチ回路２０はロジック回路にて
構成されており、制御信号×。y1 Drum pulse d whose level changes every field from the drum pulse generator 19 (3 in the NTSC system)
0Hz, 25Hz> in PAL system, switch circuit 2
0. The switch circuit 20 is made up of a logic circuit and receives a control signal x.

ｙ１ドラムパルスｄを切換信号として、ＮＴＳＣ方式の
ＰＳ（移相）方式の場合は第４図（Ａ）。FIG. 4(A) shows the case of the PS (phase shift) system of the NTSC system using the y1 drum pulse d as the switching signal.

（Ｂ）、ＰＡＬ方式のＰＳの場合は第５図（Ａ）。(B), and Fig. 5 (A) in the case of PAL system PS.

（Ｂ）、ＮＴＳＣ方式のＰＩ（位相反転）方式の場合は
第６図（Ａ）、（Ｂ）に示す出力の、■が夫々取出され
るように予めロジックシーケンスが設定されている。In the case of the PI (phase inversion) system of the NTSC system, a logic sequence is set in advance so that the outputs shown in FIGS. 6A and 6B are taken out, respectively.

第４図（Ａ）の第１チヤンネルのフィールドでは１日毎
に位相９０°進み、同図＜８）の第２チヤンネルのフィ
ールドでは１日毎に位相９０’遅れの各出力の、■が得
られる。In the field of the first channel in FIG. 4(A), the phase advances by 90° every day, and in the field of the second channel in FIG.

第５図（Ａ）の第１チヤンネルのフィールドでは１Ｈ毎
に　１８０°移相される出力の及び位相回転しない出力
■が得られ、同図（Ｂ）の第２チヤンネルのフィールド
では１日毎に位相９０’進みの出力■及び位相９０″遅
れの出力■が得られる。In the field of the first channel in Fig. 5 (A), an output whose phase is shifted by 180 degrees every 1H and an output with no phase rotation is obtained, and in the field of the second channel in Fig. 5 (B), the phase is changed every day. An output (2) with a lead of 90' and an output (2) with a phase lag of 90' are obtained.

ＰＡＬ方式では色差信号（Ｒ−Ｙ）を１日毎に１８０°
移相する必要があるので、第５図（Ａ）。In the PAL system, the color difference signal (R-Y) is transmitted 180 degrees every day.
Since it is necessary to shift the phase, Fig. 5(A).

ｆ８＞の＊印の出力のは同図のようになる。The output marked with * for f8> is as shown in the same figure.

第６図（Ａ＞の第１チヤンネルのフィールドでは１Ｈ毎
に１８０°移相される各出力＠、■が得られ、同図（Ｂ
）の第２チヤンネルのフィールドでは位相回転しない各
出力の、■が得られる。In the field of the first channel of Fig. 6 (A>, each output @, ■ whose phase is shifted by 180° every 1H is obtained,
) of each output without phase rotation is obtained in the field of the second channel.

スイッチ回路２０より取出された出力の、■は平衡変調
器４，６において夫々色差信号（Ｒ−ψ）、（Ｂ−Ｙ）
にて平衡変調され、加算器７にて加算され、加算器２１
にてバースト信号を付加され、加算器９に供給される。■ of the output taken out from the switch circuit 20 is the color difference signal (R-ψ) and (B-Y) in the balanced modulators 4 and 6, respectively.
Balanced modulation is performed in the adder 7, and the adder 21
A burst signal is added thereto and supplied to the adder 9.

バースト信号としては、ＮＴＳＣ方式ではスイッチ回路
２０の出力のをゲートしたものを用いればよく、ＰＡＬ
方式では出力■を１日毎に±　１３５°移相した信号を
ゲートしたものを用いればよい。As the burst signal, in the NTSC system, a gated version of the output of the switch circuit 20 may be used;
In this method, a gated signal obtained by shifting the phase of the output ■ by ±135° every day may be used.

なお、信号１６０ｂ＋を得るには水晶発振器等独立の回
路を用いてもよい。Note that an independent circuit such as a crystal oscillator may be used to obtain the signal 160b+.

又、低域搬送波信号ａ、ａ、ｂ、ｂの周波数は、例えば
（４４〜（１／４））ｆＨでもよい。Furthermore, the frequencies of the low-frequency carrier signals a, a, b, and b may be, for example, (44 to (1/4)) fH.

又、制御信号ｘ、ｙは第３図（Ｃ）、（Ｄ）に示す波形
に限定されるものではなく、４日周期で１Ｈ毎に順次出
力される４つのパルスを用いるようにしてもよい。Furthermore, the control signals x and y are not limited to the waveforms shown in FIGS. 3(C) and 3(D), but four pulses sequentially output every 1H in a 4-day cycle may be used. .

又、本発明回路はテレビジョンカメラ一体形ＶＴＲに限
定されるものではなく、輝度信号Ｙ１色差信号（Ｒ−Ｙ
）、（Ｂ−Ｙ）、原色信号Ｒ，Ｇ。Further, the circuit of the present invention is not limited to the VTR integrated with a television camera, but also applies to the luminance signal Y1 color difference signal (R-Y
), (B-Y), primary color signals R, G.

Ｂ等のベースバンド搬送色信号入力端子を有するＶＴＲ
において２つの色差信号から直接低域搬送色信号を得る
回路にも適用し得る。VTR with baseband carrier color signal input terminal such as B
The present invention can also be applied to a circuit that directly obtains a low-frequency carrier color signal from two color difference signals.

発明の効果 本発明回路は、水平走査周波数よりも高い周波数の互い
に９０°位相の異なる４つの低域搬送波信号を得る回路
と、４つの低域搬送波信号を１水平走査期間毎に選択し
て取出す回路と、選択された低域搬送波信号を２つの色
差信号で平衡変調する回路とにて構成したため、直角２
相変調のための９０°移相と１Ｈ毎の移相とを同一のロ
ジック回路にて行なうように構成し得、従来回路に比し
て回路を簡単に構成し得、ＩＣ化し易く、又、ＮＴＳＣ
方式、ＰＡＬ方式等のテレビジョン方式に夫々基いたロ
ジックシーケンスに従って該４つの低域搬送波信号から
所定の信号を選択するようにしたため、各種テレビジョ
ン方式に対してロジックシーケンスの粗度えだけで容易
に適用し得る等の特長を有する。Effects of the Invention The circuit of the present invention includes a circuit for obtaining four low frequency carrier wave signals having a frequency higher than the horizontal scanning frequency and having a phase difference of 90 degrees from each other, and a circuit for selecting and extracting the four low frequency carrier wave signals for each horizontal scanning period. The circuit consists of a circuit and a circuit that balance-modulates the selected low-frequency carrier signal with two color difference signals.
The 90° phase shift for phase modulation and the phase shift every 1H can be configured to be performed in the same logic circuit, and the circuit can be configured more easily than the conventional circuit, and can be easily integrated into an IC. NTSC
Since a predetermined signal is selected from the four low frequency carrier signals according to a logic sequence based on each television system such as PAL system and PAL system, it is easy to select a predetermined signal from the four low frequency carrier signals by simply adjusting the roughness of the logic sequence for various television systems. It has features such as being applicable to

【図面の簡単な説明】[Brief explanation of the drawing]

第１図及び第２図、第３図は夫々本発明回路の一実施例
のブロック系統図及びその信号波形図、第４図乃至第６
図は各テレビジョン方式におけるスイッチ回路の入力、
出力の関係を示す図、第７図は従来回路の一例のブロッ
ク系統図である。 １・・・テレビジョンカメラ信号系回路、２・・・１６
０逓倍回路、４．６・・・平衡変調器、１３〜１８・・
・フリップフロップ、１９・・・ドラムパルス発生器、
２０・・・スイッチ回路。FIG. 1, FIG. 2, and FIG. 3 are block diagrams and signal waveform diagrams of one embodiment of the circuit of the present invention, respectively, and FIGS.
The figure shows the switch circuit input for each television system.
FIG. 7, which is a diagram showing the relationship between outputs, is a block system diagram of an example of a conventional circuit. 1... Television camera signal system circuit, 2...16
0 multiplier circuit, 4.6...Balanced modulator, 13-18...
・Flip-flop, 19... drum pulse generator,
20...Switch circuit.

Claims (2)

【特許請求の範囲】[Claims] （１）２つの色差信号から平衡変調により低域変換搬送
色信号を得る搬送色信号処理回路において、水平走査周
波数よりも高い周波数の互いに９０°位相の異なる４つ
の低域搬送波信号を得る回路と、該４つの低域搬送波信
号を１水平走査期間毎に選択して取出す回路と、該選択
された低域搬送波信号を上記２つの色差信号で平衡変調
する回路とよりなることを特徴とする搬送色信号処理回
路。(1) In a carrier color signal processing circuit that obtains a low-pass converted carrier color signal from two color difference signals by balanced modulation, a circuit that obtains four low-pass carrier wave signals having a frequency higher than the horizontal scanning frequency and having a phase difference of 90 degrees from each other. , a circuit that selects and extracts the four low-frequency carrier signals every horizontal scanning period, and a circuit that balance-modulates the selected low-frequency carrier signals with the two color difference signals. Color signal processing circuit. （２）該選択して取出す回路は、ＮＴＳＣ方式、ＰＡＬ
方式等のテレビジョン方式に夫々基いたロジツクシーケ
ンスに従つて該４つの低域搬送波信号から所定の信号を
選択する回路であることを特徴とする特許請求の範囲第
１項記載の搬送色信号処理回路。(2) The selected and extracted circuit is NTSC system, PAL
The carrier color signal according to claim 1, characterized in that the circuit selects a predetermined signal from the four low frequency carrier signals according to a logic sequence based on each television system. processing circuit.