JPS60191590A - Video disc record - Google Patents

Abstract

PURPOSE:To attain reproduction still picture taking a four-field forming a common still picture pattern by adding a common identification code to the 4-field forming the common still picture. CONSTITUTION:A high definition still picture signal is inputted to a TCI encoder 1 in the period of four-field and the encoder 1 applies time axis compression multiplex to a color signal at each horizontal blanking period while keeping a luminance signal of a high definition video signal. The switching output of the high quality video signal at each four-field is inputted to an address signal generator 3, the circuit 3 counts the switching signal and generates an address signal during the vertical blanking period. The address signal is a code comprising the combination of a picture number code obtained through the count and field number codes 1-4.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a video disc code for reproducing high-quality still image signals.

(b) Track 1 records one frame of conventional NTSC color video signal.
A conventional video disc player that optically plays back a video disc record that records at a constant angular velocity during each rotation repeats a track jump to an adjacent track once per frame and continues scanning the same track to produce a still image. is running a playback. (Refer to Equity No. 54-15485) However, the video signal band is 20 MHz, and the audio signal band is 7 MHz.
In the case of a high-quality video signal of MHz, it is not possible to record one video signal per revolution. Therefore, the applicant previously proposed in Japanese Patent Application No. 58-185608 to record one field of a high-definition video signal on one round of a recording track, and during still image playback, a track jump of two tracks was repeated once every two fields. We proposed a method for still image playback.

However, in the above proposal, since the disk record is rotated at the field period, the recording/reproducing time is shortened.

Therefore, in order to lengthen the recording and reproducing time, it is conceivable to record a high-quality video signal by compressing its band. As a method for band-compressing and transmitting a high-quality video signal, a sub-sample TCI transmission method (or time-axis compression multiplexed sub-sample transmission method) has already been proposed. This method was developed in 1978.
“Television Society Technical Report” dated October 20, 2018
TEBS 91-5, January 20, 1980, page 6 of the Dempa Shimbun, and pages 123-130 of the "Research Introduction Materials" discontinued by the Japan Broadcasting Publishing Association on June 2, 1985, respectively. The TC1 method, which time-axis multiplexes the color signal with horizontal blanking, and the multiple sub-sampling method, which samples this multiplexed signal while shifting the phase of the 16.20 MHz sampling clock by 90 degrees for each field, are combined. 8. This is a method of compressing the band into a wideband video signal of IOM) Iz, and is a method of thinning out the information of each field of a high-quality video signal to 174 before transmitting it.

With this 8.10 MHz wideband video signal, it is possible to record one frame per revolution of the video disc. However, in a video disc player that continuously records wideband video signals in four fields in a spiral format, it is necessary to correctly detect the trunk jump position in order to correctly reproduce still images.

(c) Purpose of the Invention In view of the above-mentioned points, the present invention proposes a new video disc record that reproduces still images by using four fields forming a common still screen.

(2) Structure of the Invention The present invention is characterized in that a common identification signal is attached to four fields forming a common still image.

(Po) Example Hereinafter, the present invention will be explained according to an illustrative embodiment.

In this embodiment, as shown in the second section, when creating a video disc record, a high quality still image video signal is input to the TCI encoder (1) at a period of 4 fields.

Otsu's TCI Engineering>' Korg (1) compresses and multiplexes the luminance signal of a high-quality video signal directly into J= and a color signal during the horizontal blanking period.

This encoded output can be input to a sub-sample filter (2). The subsample filter is '16, 20M
A wideband video signal of 8.10 MHz is derived by changing the sampling clock of Hz by π/2 for each field and changing the sampling point for each field by changing the phase left and right.

Further, switching output of high-quality video signals every four fields is manually input to the address borrowing generation circuit 3).

This address signal generating circuit (3) generates the switching signal J1 and generates an address signal during the vertical blanking period.

This address signal is a code signal that is a combination of the image number code obtained by counting and the field number codes 1 to 4. Note that although the field number code is effective for identifying the fourth field (that is, the final field) and detecting the 1st field, it is not necessarily a necessary code.

The wideband video signal and the address signal are -C multiplexed by a multiplexing circuit (4) and then inputted to an FM modulation circuit (5). This F Mi ifi circuit (5) has a frequency shift range of 14
~16MHz, and the first lower sideband band is 6~1
The frequency is 4MHz. This FM modulated wave (referred to as an information signal) drives the optical modulation means (6) of the video disc recorder to form a spiral trunk on the disc record rotating at a cycle of t frames.

Figure 3 shows recording tracks formed on a video disc record (DR) and address signals (Ai...(Ax')...
...(AO)... is schematically shown, and since each address signal is multiplexed on a predetermined line of vertical blanking, the recording positions can be aligned in the radial direction.

The video disc player for playing back the video disc record employs the circuit shown in the figure for the first reason.

First, the reproduced output is amplified by an amplifier (7), inputted to an FM modulation circuit (8), and converted into the original wideband video signal. This wideband video signal is input to the RF conversion circuit (9) and then input to a band compression decoder attached to the high-definition television receiver.

On the other hand, the broadband video (No. E1) is also input to the synchronization separation circuit (1o), the separated synchronization signal is inputted to the extraction pulse generation circuit (11), and the extraction pulse for address signal extraction is input to the gate circuit (12). ) can be entered. A gate circuit (12) that inputs a wideband video signal inputs only an address signal to an image number discrimination circuit (13).This image number discrimination circuit (13) detects an image with the same content as the image number code of the previous field. A matching pulse is emitted when a number code is input.A counter (14) that manually generates this matching pulse.
emits a count-up output when the count value reaches 3.

In response to this count-up output, the jump pulse generating circuit (15) generates a jump pulse after one field.

Receiving this jump pulse, the tetratracking mirror l'
E1 is moved, and the reproducing beam is moved by a track in the return direction.

By this track number, recording tracks for four fields forming a common screen are continuously reproduced.

Incidentally, the above-mentioned digital pulse is generated by the above-mentioned image number discrimination circuit (
13) and as a reset pulse for the counter (14), and both circuits are reset to the initial state each time the track is changed.

Moreover, it goes without saying that in order to update the screen continuously, it is sufficient to ground the count-up pulse only once.

In the embodiment described above, the number of matching image numbers is counted, but if subcodes are used, the circuit configuration can be further simplified. That is, as shown in FIG. 4, the image number code i! 6(
If a sub-food discrimination circuit (16) is installed in place of 13), the counter (14) can be omitted by configuring it to detect subcode "4" and input its detection output to the jump pulse generation circuit (15). Needless to say, there is nothing you can do.

Furthermore, if the playback screen is not affected even if you perform a track-down immediately after detecting a new picture number code, detect the update of the picture number code and perform a 1-lap/jump. The counter can also be omitted.

(f) Effects of the Invention According to the present invention, recording tracks for four fields forming a common still image are correctly and continuously reproduced, so that the still image reproduction operation is reliable and the effect is great.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the main circuit of a video disc player according to the first embodiment of the present invention, FIG. 2 is a block diagram of the main circuit of the video disc recorder, and FIG. 3 is a block diagram of the main circuit of the video disc recorder. The schematic explanatory diagram and FIG. 4 each show a main circuit block diagram of another embodiment. Explanation of main figure numbers, (DR)...Video disc record, (A+>(A
2) (AO)... Address signal, (3)... Generation circuit. Applicant Sanyo Niki Co., Ltd. Agent Patent Attorney Shizuo Sano 8 Ward

Claims (1)

[Claims] (1) The color components of a high-quality video signal are compressed in the time axis, multiplexed in the horizontal blanking period, and band-compressed using the multiplex subsampling method. Vertical bra for 4 fields
1. A common identification signal multiplexed during the linking period. A video disc record for recording still images, which is made by recording FM modulation on a disc record that rotates at a frame period.