JPS61203792A - Video signal processing device - Google Patents

Abstract

PURPOSE:To reduce the number of component parts by digitally processing a brightness signal and color signal of VTR outputs and causing the delay by a memory. CONSTITUTION:The reproduced signal of the VTR from a terminal 1 is passed through a brightness signal processing part 15 where the brightness signal is demodulated. The demodulated signals are A/D converted at 16, and 0.5H skew is detected at 24 from the horizontal synchronization signals separated at the synchronization circuit 23. Burst gate pulses are generated at 25 and are both inputted into a control signal generator 26 from which control signals (c), (d) are produced, The brightness signals digitized at 16 are processed at 17 as prescribed and are delayed by 1H at a memory 13. The color signals passed through the LPF 2 are A/D converted and separated at 4 into color difference signals B-Y, R-Y and delayed by 0.5H at memories 7, 8. The signal delayed by 1H of the brightness signal and the signal not delayed are alternately switched by the signal (c) with the signal delayed 1H of the color difference signal and the signal not delayed, while the signal R-Y code inverted at 11 and the signal not inverted are switched at the burst period signal (d) to make D/A conversion.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is particularly applicable to video tape recorders (VTRs) in which horizontal synchronizing signals are not arranged in a direction substantially perpendicular to adjacent recording tracks or adjacent recording tracks. )
The present invention relates to a video signal processing device for special playback of still, slow, cue, review, etc. at a tape speed different from the tape speed at the time of recording in a format VTR.

In conventional VH8 type VTRs, the formats without the H sequence are the NTSC 4-hour format and the PAL 6-hour format. Video signal processing during special playback in the PAL 6-hour format will be described below.

FIG. 5 shows a recording trajectory on a magnetic tape in the PAL 6-hour system. A PAL signal burst signal is sent with the R-Y axis of the R-Y and B-Y axes inverted every horizontal period (hereinafter referred to as 1H), but in the figure, it is shown as R. , B. From FIG. 6, it can be seen that the H sync positions of one track and the adjacent track are shifted by 0.75H. Therefore, the content of the color signal also shifts by 0.75H.

Furthermore, the deviation between adjacent data required for special playback is 0.5H. As is clear from the playback and recording at the time of review shown in FIG. 6, the playback image causes a skew distortion of 0.5H before and after the noise band when transitioning to an adjacent track. Also, the color signal arrangement (R, B order)
There is no continuity at all, resulting in a screen with no color.

Conventionally, the following means have been used to correct this H discontinuity and color signal discontinuity. In FIG. 6, when the reproducing head moves from the Al track to the A[I track, the reproduced output track is discontinuous before and after the noise, causing a phase shift of 18o0.

By detecting this state and determining the time of track transition, and delaying the reproduction signal of the M2 track by 0.6H in accordance with this determination, the continuity of the Al track and the N trunk can be maintained as a luminance signal. However, looking at the color signal arrangement, the Al track and the 0.5H delayed signal of the Al track correspond to R and B, and B and R, resulting in a difference of exactly 1H as a color signal. Only the color signals were delayed by a total of 1.5H.

Next, AI) Transition from Rack to A II+ Track 2
Considering this, since the Al track has already been delayed by 0.5H, the continuity of the luminance signal is maintained. However, since a deviation of only 1H occurs in the color signal, A1
The color signal of the 1L track was delayed by 1H. In this way, each time the track is sequentially shifted, the delay amount i0.5H-OH is sequentially switched for the luminance signal every time the discontinuity of the track is determined, and the delay amount for the chrominance signal is sequentially switched to OH-+1.5H-I.
The delay amount was sequentially switched in cycles of H-0, 5H-OH-, . . . .

FIG. 3 shows a block diagram composing all of the above-mentioned means. In FIG. 3, a reproduced signal inputted from an input terminal 29 is frequency-converted from a low frequency converted color signal to a carrier color signal in a color signal processing section 28. Furthermore, the luminance signal subjected to FM modulation in the luminance signal processing section 31 is subjected to FMi tuning. A synchronization separation circuit 36 separates a horizontal synchronization signal from the demodulated luminance signal, and a skew detector 37 detects a 0.5H skew from the horizontal synchronization signal.

Control signals g and h are generated from the skew detected in the control signal generator 38. A carrier color signal, which is an output signal of the color signal processing section 28, is supplied to a 1H delay line 29 and a switch circuit 30. In the 1H delay a29, the input signal is delayed for 1H period, and the output signal is sent to the switch circuit 30.
is supplied to

The switch circuit 30 switches the color signal processing section 2 according to the control signal g.
8 and the output signal of the 1H delay line 29 are all switched.

The output signal of the switch circuit 30 and the output signal of the luminance signal processing section 31 are added in an adder 32, and the output signal of the adder 32 is supplied to a 0.5H delay line 33 and a switch circuit 34. In the 0.5H delay line 33, the input signal f0.
The output signal is delayed for 5H period and is supplied to the switch circuit 34. In the switch circuit 34, the output signal of the 05H delay line and the output signal of the adder 32 are switched by the control signal, and the output signal is output to the output mizuko 35.

FIG. 4 shows the timing of the signals e, f, g, and h shown in FIG. 3 and the amount of delay of the luminance signal and color signal.

Problems to be Solved by the Invention However, the above-described configuration has the drawback that, in addition to the usual video signal processing, a large number of components including all delay lines are required.

Furthermore, if the color signal is delayed by 1H more than the full luminance signal in order to erase the entire color array, there is a problem that color blurring occurs.

In view of the above-mentioned problems, the present invention aims to reduce the number of components of a circuit for special reproduction in a format without H alignment, and provides a complete video signal processing device for obtaining a good reproduced image 2 without color fading.

Means for Solving the Problems In order to solve the above problems, the video signal processing device of the present invention includes a first memory that delays a digitized luminance signal, and a first memory that delays a digitized color signal. 2, a skew detector for detecting a skew of 0.5H, and a control signal generator for generating all control signals based on the output signal of the skew detector; This device has a configuration 2 that uses a memory and a second memory to delay a luminance signal and a color signal.

Operation The present invention achieves a complete reduction in the number of parts by performing all digital processing of the luminance signal and color signal and delaying them by memory using the above-described configuration. In addition, as a means of matching the color arrangement, the sign of the R-Y signal during the burst period is completely inverted, so the delay amount of the color signal and the luminance signal can be made the same, and a good reproduced image without color shift can be obtained. be able to.

Embodiment Hereinafter, a video signal processing device according to an embodiment of the present invention will be described.
The explanation will be given with reference to all the drawings. In FIG. 1, a reproduced signal inputted from an input terminal 1 is FM-modulated into a luminance signal in a luminance signal processing section 16. A synchronization separation circuit 23 completely separates a horizontal synchronization signal from the demodulated luminance signal, and a skew detector 37 detects a 0.6H skew from the horizontal synchronization signal. Further, the burst gate generator 25 generates all burst gate pulses indicating the burst period from the horizontal synchronizing signal. The control signal generator 26 generates a control signal C9di from the 0.6H skew and the burst gate pulse. A
The luminance signal digitized by the /D (analog/digital) converter 16 is subjected to operations such as dropout compensation in the luminance signal processing section 17, and then sent to the first memory 18 and switch circuit 19, which performs a 1H period delay. Supplied. Further, the output of the first memory 18 is also supplied to the switch circuit 19, and is switched by the control signal C. The output signal of the switch circuit 19 is converted into an analog signal by a D/A (digital/analog) converter 2o,
It is supplied to an adder 21. Color signal is low pass filter 2
A low-frequency converted color signal is extracted at the MU/D converter 3.
is digitized in the decoding circuit 4, and 2
The signal is separated into two color difference signals B-Y and RY signals. R-Y
.

The B-Y signal has its crosstalk removed in each comb filter 6.6, and is supplied to a second memory 7.8 and a switch circuit 9.1o which performs a delay of 0.5H period. Switch circuits 9 and 10 are switched according to control signal C. R-Y output from switch circuit 9
The signal is divided into a signal whose sign is inverted in the sign inverting circuit 11 and a signal which does not pass through the sign inverting circuit 11.
In the switch circuit 12, one signal is taken out according to the control signal d and supplied to the encode circuit 13. Still, the BY signal output from the switch circuit 10 is also supplied to the encode circuit 13. The encoder circuit 13 converts the signal into a carrier color signal, the D/person converter 14 converts the signal into an analog signal, and the signal is supplied to the adder 21 . Adder 21
The luminance signal and chroma signal added at output terminal 2
Output from 2.

Regarding the video signal processing device configured as above, the PAL 6 shown in FIG. 6 will be described below using FIGS.
The operation when review playback is performed in the time format will be explained.

FIG. 2 shows the timing of signals a, b, c, and d shown in FIG. 1, the delay amounts of the luminance signal and color signal, and the burst period R-
It shows the period during which the sign of the Y signal is inverted.

The difference from the conventional example shown in FIGS. 3 and 4 is that the luminance signal and color signal are digitally delayed, thereby realizing reduction and rationalization of circuit components. Furthermore, in order to match the color signal arrangement, the color signal was delayed by 1H more than the luminance signal, but in this embodiment, the color signal arrangement is matched by reversing the sign of the burst period of the R-Y signal. I did it like that. As a result, the delay times of the luminance signal and the color signal can be made the same, and a reproduced image without color fading can be obtained.

Effects of the Invention As described above, the present invention includes a first memory that delays a digitized luminance signal, a second memory that delays a digitized color signal, and a skew that detects a skew of 0.15H. and a control signal generator that generates a control signal based on the output signal of the skew detector, and generates a luminance signal using the first memory and the second memory according to the control signal. By employing a configuration that delays the color signal, it is possible to reduce the number of parts in the circuit for special reproduction in a recording formant without H alignment.

In addition, the digitized color signal is converted into two color difference signals R.
-Y, B-Y signals, and when the control signal is configured to invert the sign of the R-Y signal during the burst period, the PA
It is possible to eliminate color blurring during special reproduction in the recording former 7) of the L system without H alignment, and to obtain a good reproduced image.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a video signal processing device according to an embodiment of the present invention, FIG. 2 is a timing diagram of FIG. 1, FIG. 3 is a block diagram of a conventional video signal processing device, and FIG. 4 is a block diagram of a conventional video signal processing device. FIG. 6 is a timing chart showing a recording pattern on a magnetic tape in the 6-hour PAL system of the VH5 system. 1...Input terminal, 2...Low pass filter, 3.16...Person/D converter, 4...
. . . Decoding circuit, 5.6 . . . Comb filter, 7.8 . . . Second memory, 9, 10, 12.
19... Switch circuit, 11... Sign inversion circuit, 13... Encoding circuit, 14.20...
...D/mu converter, 15... Luminance signal demodulation section, 17... Luminance signal processing section, 18...
...First memory, 21... Adder, 22...
...Output terminal, 23...Synchronization signal separation circuit, 24...Skew detector, 26...
Burst gate generator, 26... Control signal generator. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 3
Figure 5: 1 and 3 tables

Claims (2)

[Claims] (1) A first memory that delays the digitized luminance signal, and a second memory that delays the digitized color signal.
, a skew detector for detecting a skew of 0.5 horizontal period, and a control signal generator for generating a control signal based on the output signal of the skew detector; A video signal processing device characterized in that it is configured to delay a luminance signal and a color signal using a memory and a second memory. (2) The digitized color signals are two color difference signals B
2. The video signal processing device according to claim 1, wherein the signals are R-Y and R-Y signals, and the sign of the R-Y signal during a burst period is inverted by a control signal.