JPH0424916B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a digital signal reproducing device, which reproduces a digital luminance signal which is a time-series composite signal of pixel data from each pixel arranged in a matrix and constitutes one screen; A color difference signal is divided into pixel data of a pixel group in a fixed number of adjacent rows or columns, and a header signal (identification signal) having a synchronization signal and an address signal is added to each divided signal. By reproducing a recording medium on which a time-series synthesized digital video signal consisting of An object of the present invention is to provide a digital video signal reproducing device capable of rewriting an image displayed on a computer, reproducing and displaying a partial moving image, and furthermore, capable of reproducing a digital video signal with less influence of word shift in the digital video signal. .

In recent years, digital video signals and digital audio signals obtained by digital pulse modulation such as pulse code modulation (PCM) are being used to record digital video and audio signals on disk-shaped recording media (hereinafter referred to as "disks") using intermittent pit rows. A system is being actively developed in which the previously recorded signal is read and reproduced by recording the signal as a change and detecting a change in the intensity of light or a change in capacitance from the disk. Among these, a recording method for a digital audio disk is known in which a digital video signal related to color still image information is added as additional information to a digital audio signal and recorded on the same track on the disk. Usually, a plurality of music programs are recorded on the same surface of such a digital audio disk, and digital video signals related to color still image information are recorded corresponding to each music program, but when this disk is played back, Music programs can be played using a universal playback system.

On the other hand, since the television format for video signal playback is not universal worldwide, video signals must be played back in regions or countries where the television format differs from the one in which the video signal was recorded on such a disc. As for the signal, it is necessary to convert it into a signal format that complies with the television system of the region or country in which it is to be reproduced and displayed. In particular, since the above-mentioned digital video signal concerns color still images that play an auxiliary role to aid the imagination of the listener who listens to the reproduced sound of the digital audio signal, the above-mentioned disk is compatible with the differences in television systems around the world. A universal method regardless of
It is desirable to reproduce the signal format in accordance with each television system.

Therefore, in view of the above points, the present invention records a color still image as a digital video signal based on a component encoding method, and also uses a predetermined header signal that can further correct a partial screen or reproduce a partial moving image. A digital video signal is reproduced from a recording medium recorded on a periodic basis in an optimal signal format based on a header signal.
One embodiment will be described below with reference to the drawings.

First, the recording system for the digital video signal to be reproduced by the apparatus of the present invention will be described. FIG. 1 shows a block diagram of an example of the main part of the recording system for the digital signal. In the figure, 1 is a video signal source such as a color television camera, flying spot scanner, VTR, etc.
A TV synchronization signal from a TV synchronization signal generator 2 is supplied, and three primary color signals relating to a color still image to be recorded are extracted and supplied to a matrix circuit 3. The matrix circuit 3 has 625 scanning lines, a luminance signal Y and a color difference signal (B) with a horizontal scanning frequency of 15.625kHz.
-Y) and (RY) and supply these to AD converters 4, 5 and 6 separately. On the other hand,
The output TV periodic signal of the TV synchronization signal generator 2 is supplied to clock generators 7, 8, 12 and 13, respectively.

AD converter 4 is a luminance signal Y with a band of about 4.5MHz.
is sampled at a sampling frequency of 9 MHz using a 9 MHz clock from a clock generator 7, quantized with an 8-bit quantization number, converted into a digital luminance signal, and this signal is supplied to a memory 9. The AD converter 5 receives a color difference signal (B-Y) whose band is approximately a fraction of the luminance signal in consideration of well-known human visual characteristics.
and (RY), one color difference signal (B-Y)
is sampled at a sampling frequency of 2.25 MHz based on a 2.25 MHz clock signal from a clock generator 8, quantized with an 8-bit quantization number, converted into a digital color difference signal, and this signal is supplied to a memory 10. Furthermore, the AD converter 6 receives the above color difference signal (R-Y).
Based on the clock signal from the clock generator 8, the sampling frequency is 2.25MHz, similar to the AD converter 5.
It is converted into a digital color difference signal with a quantization number of 8 bits, and this signal is supplied to the memory 11.

The memory 9 writes the above-mentioned digital luminance signal for one frame, for example, using the output pulses from the memory write controller 12, and sequentially performs read operations using the output pulses from the memory read controller 14. The digital luminance signal supplied to this memory 9 is a digital luminance signal at, for example, 456 sample points (456 pixels in the horizontal direction) per scanning line. In other words, a luminance signal with 625 scanning lines and a horizontal scanning frequency of 15.625kHz is
When sampling at 9MHz, the sampling points of one scanning line are 576.
(=9×10 ⁶ /15625), but among the video signals shown in horizontal scanning period units in Figure 2, the image period VT that actually contains image information is about 80% of one horizontal scanning period (1H). On the other hand, horizontal and vertical synchronization signals and color burst signals can be added in the playback device, so the above video period VT
It is assumed that digital luminance signals of 456 sample points are supplied to the memory 9. Moreover, the digital luminance signal read out from this memory 9 is
Of the 625 scanning lines, this is a digital luminance signal related to 572 scanning lines containing image information, and the sampling frequency is 94.5kHz (or 88.1kHz) and the quantization number is 8 bits.

Furthermore, the digital color difference signal for one frame, for example, is written into the memories 10 and 11 based on a write control signal from a memory write controller 13, and the stored data is read out based on an output read control signal from a memory read controller 14. Since the sampling frequency of the digital color difference signals supplied to the memories 10 and 11 is 2.25MHz, which is the same as that of the digital luminance signal, each digital signal has 114 (=456/4) sampling points per scanning line. These are read out from the memories 10 and 11 as first and second digital color difference signals with a sampling frequency of 94.5 kHz (or 88.2 kHz) and a quantization number of 8 bits. These first and second digital color difference signals are 572 pixels similar to the digital luminance signal.
Concerning image information of scan lines of a book. Memory 9, 10
and each output digital signal of 11 is connected to a switching circuit 15.
are supplied respectively.

On the other hand, the input terminal 16 receives a signal generated each time the still image signal to be recorded is switched, and is supplied to the header signal generator 17. As will be described later, the header signal generator 17 generates a 16-bit header signal, which is a set of signals and codes constituting the header section, and supplies this to the memory 18. The memory 18 stores the header signal at a sampling frequency of 47.25 kHz (or
44.1kHz) is read out with a quantization number of 16 bits and supplied to the switching circuit 15.

The switching circuit 15 connects the memories 9, 10, 11 and 18
The digital signals from the digital video signal generator are switched in a predetermined order to generate digital video signals in the signal formats shown in FIGS. 3 to 5, which are supplied to the digital recorder 19 and recorded therein. Note that the memory read controller 14 is activated in synchronization with the clock signal from the digital recorder 19.
A read control signal is output from.

Next, the signal format of the above digital video signal will be explained in more detail. Switching circuit 1
The digital video signal taken out from 5 is 12
The header part of a word and, for example, a component-encoded digital video signal part of 684 words for 2H (H is a horizontal scanning period) are synthesized alternately in time series, and one word at the end is Signal transmission end signal (hereinafter also referred to as "EOD signal")
is added to the signal, and when one frame worth of image information is transmitted, as shown in Figure 3,
286 header parts of 1 to H286 (however, H3 to H286 are omitted from illustration) and V1 to V28.
A total of 199,057 words of digital video signals are recorded, consisting of 286 video signal sections indicated by 6 (however, V3 to V285 are omitted from illustration) and one word of EOD signal indicated by EOD. Therefore, this 1
The digital video signal for a frame consists of one channel 16 in one block of signals shown in FIG. 8, which will be described later.
When one word is transmitted in bits, the signal period of this one block is selected to be equal to the reciprocal of the sampling frequency of the header signal, so when the sampling frequency is 47.25kHz, it takes approximately 4.21 seconds. It is transmitted in approximately 4.51 seconds at 44.1kHz.

An example of the signal format of the header sections H1 to H286 is as shown in FIG. In the figure, the vertical direction shows the bit arrangement, and the upper part shows the bit arrangement.
MSB (Most Significant Bit)
The lower side indicates the LSB (least significant bit), and the horizontal direction indicates the time. T indicates the transmission time of one word. First 1 of header signal
A synchronization signal 20 is arranged in the word to indicate the start of the header signal, and its upper 8 bits have a hexadecimal value of "FF", and the lower 8 bits have a hexadecimal value of "FE". ” has been selected. Therefore,
When the synchronization signal 20 is expressed as a binary number, its upper 8 bits are all "1" and its lower 8 bits are "11111110".

Here, the values "FF" and "FE" of the synchronization signal 20 are values assigned only to the synchronization signal in the digital video signal, and are values assigned only to the synchronization signal in the digital video signal.
1 to V286, the first
In the recording system shown in the figure, the value is changed to "FD" in advance to prevent the playback device described later from mistakenly identifying it as a synchronization signal. Furthermore, this “FF”
This value indicates the brightest image data of the video signal, but normally this image data and the slightly darker "FE" image data hardly appear.
There is no practical problem in assigning these values to the synchronization signal 20.

The second header signal next to the synchronization signal 20 above
Various identification codes are transmitted to the word word.
First, an image type identification code indicated by "MODE" is placed in the upper 4 bits. This code determines whether the digital video signal to be recorded is a standard still image (the above explanation for Figure 1 was based on the example of a standard still image) or a moving image using a run-length code. Or, for example,
This is a code that indicates whether it is a high-definition, high-quality still image, such as 1125 scanning lines. Next, a transmission channel identification code designated as "1P/2" is placed in the fifth upper bit. This code is a code that identifies which channel out of the four transmission channels described below, the digital video signal is transmitted.When the value is "1", it is transmitted on 1P, that is, the 4th channel. (This example will be explained using this case as an example),
When it is "0", it indicates that it is transmitted using 2P, that is, a total of two channels, the fourth channel and the third channel. In the case of 2P, the types of images (for example, landscapes, portraits, performance scenes, etc.) of the digital video signals transmitted on the 4th channel and the 3rd channel are made different from each other, so that viewers can choose the one they like. You can select and enjoy the images. Alternatively, the same image may be transmitted by one word each in the fourth channel and the third channel, that is, equivalently, the sampling frequency is doubled.

Next, in the sixth upper bit of the second word of the header signal shown in FIG. If the value is "1", it is for one frame, and if the value is "0", it is for one field. Is the digital video signal transmitted in units of one frame?
The signal format of the video signal section (described below) differs depending on whether it is transmitted in field units.
The reproducing device detects this and captures an image signal according to the signal format at that time.
In addition, a screen transmission identification code indicated by "A/" is placed in the next 1 bit of this image information amount identification code, and when the value is "1", the digital video signal of a still image to be displayed on the entire screen is placed. This indicates that the digital video signal will be transmitted (so-called full-screen transmission), and if the value is "0", it will be displayed on a part of the screen, thereby indicating that a so-called partially rewritten digital video signal will be transmitted.

Furthermore, the "1" shown in FIG. 4 is a binary "1", and the values of the codes placed up to the upper 7th bit are all "0", and the 8th bit is also "1". When the signal becomes 0, the EOD signal shown in Figure 3 has both the upper 8 bits and lower 8 bits set to 0.
It may be mistakenly detected as an EOD signal, so "1" is placed to prevent this.

In Figure 4, "SE" indicates a 2-bit special effect code, which is used when a still image displayed on the screen is displayed with special effects such as a fade-in or a screen change from the top or left side of the screen. ,
This is a code to identify it. The next two bits of the above special effects code "SE" are the scanning line number conversion code shown as "6LMODE", and the next two bits are the picture code for identifying the program type shown as "PG". Species identification codes are arranged respectively.

The scanning line number conversion code "6LMODE" converts digital video signals with 625 scanning lines.
When converting to 525 scanning lines on a playback device,
This is a code indicating one of four types of mixing ratios required when converting the number of scanning lines by converting image information of six scanning lines into image information of five scanning lines. That is, when performing the above conversion of the number of scanning lines, the number of scanning lines is 625, shown as 1 to 6 in FIG. 6A.
Based on the image information of the first to sixth scanning lines in this method, the number of scanning lines is 525, shown as 1 to 5 in Figure B.
In this method, image information from the first scanning line to the fifth scanning line is created, but in order to create image information for the first scanning line (1H of the 1st field) in the 525 scanning line method, The image information of the first scanning line (1st H of the first field) and the second scanning line (1st H of the second field) of the 625 scanning line method is
Make by multiplying by 3/4 and 1/4 respectively.

Here, the digital data is divided into 1 bit each.
As is well known, when shifting toward the LSB, the amount of data becomes 1/2, and when further shifting one bit at a time toward the LSB, the amount of data becomes 1/4. Therefore, since the above 3/4 times is the sum of 1/2 times and 1/4 times, the digital data of the first scanning line of the above 625 scanning line system is shifted one bit at a time in the LSB direction. By adding the first digital data obtained by shifting 2 bits in the LSB direction and the second digital data obtained by shifting 2 bits at a time in the LSB direction, image information that is 3/4 times the image information of the first scanning line can be obtained. By adding to this the digital data obtained by shifting the digital data of the second scanning line of the 625 scanning line system by 2 bits each in the LSB direction, the second scanning line of the 525 scanning line system is generated. Image information for one scanning line will be obtained.

Thereafter, in the same manner as above, as shown in FIGS. 6A and 6B, the second, third, fourth, and
The image information of the fifth scanning line is the second and third, third and fourth, fourth and fifth, and fifth of the 625 scanning line system.
It is obtained by mixing the image information of the and sixth scanning lines at a predetermined mixing ratio. As can be seen from Figure 6A and B, these mixing ratios are (3/4, 1/4), (1/2, 1/2), (1/4, 3/4), (0, 1 )
Since it is given in four types of patterns, by giving the mixing ratio value for the scanning line to be obtained in advance with the code shown in the above "6LMODE", it is possible to use the 525 scanning line method on the playback device. can be easily converted.

Note that if this code "6LMODE" is not given, in the case of the n-th scanning line, it is necessary to calculate the mixing ratio from the remainder when dividing this by 6.

Next, the picture type identification code "PG" indicates that when digital video signals are transmitted independently using two channels, the fourth channel and the third channel, Assuming that the third channel transmits a special image in which digital video signals of several types of images are synthesized in time series, how many types (up to 4 (type) indicates the value of the category number assigned to each image. Each of the images transmitted through this third channel requires display continuity, and is an image for which it is inconvenient to switch to a different type of image in the middle of display (for example, musical scores, landscapes, illustrations, performers, etc.), The picture type identification code "PG" indicates a category number assigned according to the type of these images. Therefore, if the viewer selects to play back images of the third channel and specifies a desired category number, only the images of that category number will be played continuously, and the images of other category numbers will be played continuously. You will no longer be interrupted by images.

Furthermore, the 1-bit codes shown as "B19W" and "B19R" in FIG. 4 are the write designation code and read designation code for two frame memories in the playback device, which will be described later, and both are "0" (or When it is "1"), pixel data of the digital video signal is written into the first (or second) frame memory, and the stored data is read out and displayed on the screen. This means changing the content of the image while displaying it, resulting in
A video can be displayed on a portion of a still image. On the other hand, when "B19W" is "0" and "B19R" is "1", the pixel data is read from the second frame memory and displayed while writing the pixel data to the first frame memory. EOD after completing frame memory write operation
The signal switches the display screen from the second frame memory to the first frame memory. Further, when "B19W" is "1" and "B19R" is "0", the pixel data read from the first frame memory is displayed while writing the pixel data to the second frame memory, contrary to the above.

Next, address signals 21a, 22a, 23a, and 24a, indicated by B3 to B18, are arranged in the third to sixth words of the header signal shown in FIG. 4, respectively, and are transmitted following this header signal. This figure shows address signals for the memory circuit of two pixel data (pixel sample values) of the upper 8 bits and lower 8 bits of each word of the video signal portion to be processed. Here, the number of scanning lines of color television signals in the world is 625 or 525, and the digital video signal in the present invention is actually a time-series composite signal of pixel data of 572 scanning lines containing image information. However, since it is transmitted using a 625-scanning-line method, when playing back using a 525-scanning-line method, the number of scanning lines is converted in the playback device as described above, and then stored in the memory circuit. . Therefore, this memory circuit address signal has different values for the two pixel data, the upper 8 bits and lower 8 bits of one word, and different values for the 625 scanning line system and the 525 scanning line system. Four address values would be required. Therefore, the address signal 21a indicates the address value of the upper 8 bits of image data of one word of the video signal portion in the 625 line system, the address signal 22a indicates the address value of the lower 8 bits of pixel data of the 625 line system, and the address signal 23a indicates the address value of the pixel data of the lower 8 bits of the 1 word of the video signal section in the 625 line system. The address value 24a of the upper 8 bits of pixel data in this method is assigned to indicate the address value of the lower 8 bits of pixel data in the 525 method.

The seventh to twelfth words of the header signal shown in FIG. 4 have the same configuration as the first to sixth words described above, and the synchronization signal 25 of the seventh word is 20, the only difference is that both the upper 8 bits and the lower 8 bits have hexadecimal values of "FF", and other various codes of the 8th word and the address signal 21
b, 22b, 23b, 24b are various codes of the second word and address signals 21a, 22a,
The same content as 23a and 24a is selected. This is due to the following reason. As described later, the digital signal recorded on the disk 40 shown in FIG. 7 includes error correction signals (indicated by P and Q in FIG. 8), which correct errors occurring in the transmission path. Most of the data can be corrected, but there are rare cases where it cannot be corrected.In this case, for digital audio signals, data is corrected using an interpolation circuit, and for digital video signals, adjacent pixel data is corrected. Taking advantage of the fact that the values are often approximate, there is little problem in correcting the pixel data using the immediately preceding pixel data.

However, when there is no data correlation between adjacent words, such as in a header signal, it is difficult to perform the above correction, and if the contents of the header signal are not transmitted, the digital video signal immediately after it is Therefore, for example, 2H worth of pixel data will be missing. Therefore, in order to avoid these inconveniences, the information in the header section is sent twice as shown in Figure 4.
Even if the first half of the header signal is not reproduced on the transmission path, the second half of the header signal is used to capture pixel data. Since the synchronization signals 20 and 25 have different values, it is possible to identify whether the synchronization signal of the first half header signal portion is the synchronization signal of the second half header signal portion.

Next, the video signal sections V1 to V28 shown in FIG.
6, FIG. 5 shows an embodiment of the signal format of the video signal section V1. In this figure, the vertical direction shows the bit array, the upper side shows the MSB, the lower side shows the LSB, and the horizontal direction shows the time, which is the same as in FIGS. 3 and 4. In this embodiment, 286 video signal sections V1
As mentioned above, each of ~V286 is composed of 684 words, but in each video signal section, the pixel data of one scanning line among the pixel data of adjacent scanning lines is arranged in the upper 8 bits, Pixel data of the other scanning line is placed in the lower 8 bits and transmitted. Therefore, the signal format of the first video signal section V1 is as shown in FIG. 5, where the upper 8 bits of each word correspond to each sample of the first scanning line (1H of the first field) located at the top of the screen. A digital video signal sequence of points is arranged (that is, pixel data is arranged from the first row of pixels of a plurality of pixels arranged in a matrix to form one screen), and the lower 8 bits of each word are , the second scanning line located second (the second scanning line of the second field)
1H) of each sample point (ie, pixel data from the pixel group in the second row) is arranged.

Further, in FIG. 5, Y0 to Y455 (however, Y10 to Y455 are not shown) indicate the respective arrangement positions from the first sample point to the 456th sample point of the digital luminance signal of the first scanning line, and Y456 to Y911
(However, Y466 to Y911 are not shown) is the second
From the first sampling point of the digital luminance signal of the scanning line
The placement positions of up to 456 sample points are shown. Also (R-
Y)0~, (RY)113, (B-Y)0~(B
-Y) 113 (However, (RY) 2 ~ (RY)
113 and (B-Y)2 to (B-Y) 112 (not shown) are the digital color difference signals (R-
Y) and (BY) from the first sample point to the 114th sample point are shown. Furthermore, (RY) 114~
(RY) 227, (B-Y) 114 ~ (B-Y)
227 (However, (RY) 116 ~ (RY) 2
27 and (B-Y) 116 to B-Y226 (not shown) are the digital color difference signals (R-
Y) and (BY) from the first sample point to the 114th sample point are shown. Therefore, the video signal section V
1 consists of 2H worth of pixel data groups of the first and second scanning lines, including pixel data of four sample points of the digital luminance signal and one each of two types of digital color difference signals.
The signal format is such that six pixel data consisting of pixel data of one sample point is regarded as one unit, and the signal is transmitted repeatedly for each unit. It should be noted that video signal sections V2 to V286 are also configured in the same signal format as V1. The reason for arranging the pixel data of two adjacent scanning lines in the same video signal section in this way is to take into consideration the case where the number of scanning lines is converted from a 625-line system to a 525-line system.
This is to facilitate the conversion of the number of scanning lines. Note that the EOD signal is 16 bits all "0", but in order to prevent it from being mistakenly detected as this EOD signal, the video signal sections V1 to V2 are
If the value of each word of 86 is all "0",
It is changed to a different value that is close to all "0", such that only the LSB is "1".

Next, a recording system for recording digital video signals in signal formats as shown in FIGS. 3 to 5 on a disk in time series along with digital audio signals will be explained. In the present invention, the digital video signal is transmitted through one or two of a total of four transmission channels.
The digital video signal and the digital audio signal are transmitted through the transmission path of one channel, and the digital audio signal is transmitted through the transmission path of other three or two channels.Here, we will explain the case where both the digital video signal and the digital audio signal are transmitted through the transmission path of two channels. . FIG. 7 shows a block system diagram of another embodiment of the main part of this recording system. In the same figure, the same components as in FIG. Contains signals for central sound localization,
As a result, real image localization of the central sound source and expansion of the listening range, which could not be obtained with conventional two-channel stereo, can be achieved. 33 is a start signal input terminal;
Reference numeral 34 is an input terminal for a cue signal generated each time the music program of the three channels of analog audio signals is switched from the previous music program to another music program.

Here, assuming that a digital signal with a sampling frequency of 47.25 kHz and a quantization number of 16 bits is recorded on one track in time series for four channels as the amount of information for one channel on a disk 40, which will be described later. The three channels of analog audio signals are sampled by the AD converter 35 at a sampling frequency of 47.25kHz for each channel, and the quantization number is
It is converted into a 16-bit digital audio signal (PCM audio signal) and supplied to the signal processing circuit 37. At the same time, a digital video signal having a signal format as shown in FIG. 3, which is reproduced by the digital recorder 19, is reproduced at a sampling frequency of 47.25 kHz and a quantization number of 16 bits, and is supplied to the signal processing circuit 37. Also, input terminal 3
The start signal coming into 3 and the queue signal coming into input terminal 34 are respectively supplied to a control signal generating circuit 36, which generates a control signal having the configuration shown in FIG. 9, which will be described later. This control signal is transmitted to the regeneration needle 74.
This is a signal used for position control (random access) of pick-up playback elements such as
The signal is supplied to the signal processing circuit 37 described above.

The signal processing circuit 37 rearranges the input digital signals and control signals of a total of four channels of 16 bits from parallel data into serial data, and also processes the digital signals of each channel for each predetermined interval. Separate them, interleave them, and time-division multiplex them. Then, a recording signal is generated by adding an error code correction signal, an error code detection signal, and a synchronization signal bit indicating the start of a block (frame).

FIG. 8 is a diagram schematically showing an example of one block (one frame) in the recording signal generated as a result of signal processing by the signal processing circuit 37.
It consists of 130 bits, and its repetition frequency is the same as the sampling frequency, for example 47.25kHz.
SYNC is a 10-bit fixed pattern synchronization signal bit indicating the start of a block, Ch-1 to Ch-3 are 16-bit digital audio signals of the above three channels, and Ch-4 is reproduced from the digital recorder 19 above. The figure shows each multiplex position of one word of a 16-bit digital video signal. P and Q shown in FIG. 8 are 16-bit error code correction signals, for example, P=W ₁ W ₂ W ₃ W ₄ (1) Q=T ⁴・W ₁ T ³・W ₂ T ² This is a signal generated by the formula W ₃ T·W ₄ (2). however,
In formulas (1) and (2), W ₁ , W ₂ , W ₃ , W ₄ are Ch-1 to Ch-4
each of the 16-bit digital signals (usually digital signals in different blocks), T is an auxiliary matrix of a given polynomial, and T denotes the modulo-2 addition of each corresponding bit.

Furthermore, in Fig. 8, CRC is a 23-bit error code detection signal, and Ch-1 arranged in the same block
~Ch-4, P, Q words, for example, X ²³ +X ⁵
+X ⁴ +X+1 is the 23-bit remainder obtained by dividing the signal from the 11th bit to the 129th bit by the above generating polynomial during playback. When the remainder is zero, it is used to detect that there is no error. Furthermore, in FIG. 8, Adr is the control signal, each bit of which is dispersed, and one bit is transmitted in one block. For example, all bits of the control signal are transmitted in 126 blocks (that is, the control signal is 126 (consists of bits). Therefore,
If the rotation speed of disk 40 is 900 rpm,
Since 3150 blocks are recorded and reproduced per one rotation of the disk, the above 126-bit control signal is recorded and reproduced 25 times during one rotation of the disk.

FIG. 9 schematically shows an example of the structure of the above control signal. The total 126-bit control signal consists of a 42-bit first chapter code CP-1 and a 42-bit second chapter code CP-1.
It consists of a chapter code CP-2 and a 42-bit time code TC. The first chapter code CP-1 is a 17-bit synchronization signal,
A 4-bit mode signal, an 8-bit chapter signal, a 12-bit chapter local address, and a 1-bit parity obtained by adding the signal bits from the mode signal to the chapter local address modulo 2. The second chapter code CP-2 also has the same structure and the same values as the first chapter code CP-1, except for the value of the synchronizing signal. The above mode signal is a signal indicating the type of 4-channel digital signal recorded on the disk 40. For example, when it is "1100", 3-channel digital audio signal and 1-channel digital video signal are recorded. "1101"
When , a 4-channel digital audio signal is recorded, when "1110", two types of 2-channel digital audio signals are recorded, and when "1111", a 2-channel digital audio signal and a digital video signal are recorded. 2
Indicates that the channel is being recorded. The chapter signal is a signal indicating the number of the recorded music program from the signal recording start position on the disk 40.

Also, the time code TC shown in Figure 9 is, for example, 17
A 4-bit mode signal indicating the type of the 4-channel digital signal recorded on the disk 40 as well as a 4-bit synchronization signal and a mode signal in the first and second chapter codes CP-1 and CP-2. ,
A total of 16-bit time identification code indicating the position of the recorded music program on the disk 40 as the total time from the signal recording start position, and a binary code that increases by 1 for each rotation of the disk 40 and has a value from 0 to 14. Shown as 4
It consists of a 1-bit track number code and a 1-bit parity code. The above time identification code is expressed in minutes and seconds, and its minimum unit is 1 second, but if the disk 40 rotates at 900 rpm, it will rotate 15 times per second.
Even if the time identification codes have the same value, the music program recording position can be identified each time the disk 40 rotates by the track number.

1 block shown in FIG. 8 from the signal processing circuit 37
A 130-bit digital signal is sequentially taken out in series in block units, and is sent to the modulation circuit 3 shown in FIG.
8, where it is modulated using, for example, a modified frequency modulation (MFM) modulation method, and then frequency-modulated on a carrier wave of, for example, 7 MHz, to produce a frequency-modulated wave signal. This frequency modulated wave signal is recorded on a disk 40 by a recording device 39 using a laser beam or the like.

When the disc recording method previously proposed by the present applicant is applied, the recording device 39 described above has a configuration as shown in FIG. 10. In the figure, a laser beam emitted from a laser light source 41 is removed by an optical modulator 42 to remove drift and noise of the laser beam, and then reflected by a reflecting mirror 43 to form a half mirror 4.
4 into two optical paths. One of the divided laser beams is modulated in the optical modulator 4 by the output frequency modulated wave signal of the modulation circuit 38 from the input terminal 46 and a third tracking control reference signal fp3 to be described later, and is then modulated into the first laser beam. It is assumed to be a modulated light beam. The other divided laser beam is sent to the recording master 4 from the input terminal 48 at the optical modulator 47.
9, the first or second tracking control reference signal fp1 or fp, which will be described later, alternately enters every rotation period.
2 into a second modulated light beam.

The first modulated light beam is reflected by a reflecting mirror 50, has its optical path changed, and passes through an information recording optical system consisting of cylindrical lenses 51 and 52, a slit 53, and a convex lens 54, thereby forming a rectangular shape on the recording master 49. It is shaped into a light. On the other hand,
The second modulated light beam is shaped into a circular light on the recording master 49 by a tracking recording optical system consisting of a convex lens 55, a slit 56, and a convex lens 57, and then its optical path is changed by a reflecting mirror 58.
The first and second modulated light beams, each shaped into a desired shape, are combined on substantially the same optical axis by a polarizing prism 59, pass through a half mirror 60, and have their optical paths changed by a prism 61. Furthermore, the glass substrate 6 passes through a slit 62 and a recording lens 63.
A recording master 4 on which a photosensitive agent layer 65 is formed.
9, a first modulated light beam 66 is focused in a rectangular shape, and a second modulated light beam is focused in a circular shape 67.

The recording master disk 49 is disk-shaped and is rotated synchronously at a constant speed.The light reflected from the half mirror 60 is applied to a signal monitoring system 68, and the light reflected from a prism 61 is applied to a monitoring optical system 69. Added. The distance between the two modulated light beams on the recording master 49 is measured by a monitoring optical system 69, and the deviation is monitored by a signal monitoring system 68, and the deviation is detected by moving the cylindrical lens 51 up and down in the figure. Make corrections.

The recording master disc 49 is subjected to a known development process and a disc making process to create a stamper disc. On the disk 40 copied by this stamper board, the three channels of digital audio signals described above and the one channel digital video signal having the signal formats shown in FIGS. 3 to 5 are sequentially recorded in the signal format shown in FIG. 8. A spiral main track in which the frequency modulated wave of a signal synthesized in time series in block units is recorded as an intermittent bit string, and approximately in the middle between the track center lines of adjacent main tracks. Single-frequency burst-like first and second tracking control reference signals fp1 and fp2, each of which is in a band lower than the band of the frequency modulated wave, are recorded by an intermittent bit string for each rotation period of the disk. A third tracking control reference signal fp3 is recorded in the main track at the switching connection portion of fp1 and fp2. Further, this disk does not have a guide groove for tracking the regenerated needle, and has an electrode function.

In this way, the component encoded digital video signal portion, which is a time-series composite signal of pixel data from each pixel arranged in a matrix on the screen, is divided into pixel data of two adjacent rows of pixel groups, A header signal having a signal format as shown in FIG. 4 is added to each divided signal, and
A digital video signal with an EOD signal added to one word at the end is synthesized with a digital audio signal in time series, and is sequentially recorded word by word on the disk 40.

Next, a device for reproducing digital signals recorded on the disk 40 will be explained. FIG. 11 shows a block system diagram of an embodiment of the digital signal reproducing device according to the present invention. In the figure, the disk 40 is placed on a turntable (not shown).
It can be rotated synchronously at 900rpm. disk 40
As shown in FIG. 12, on the top is a track width TW made up of repeated flat surfaces 70 and bits 71, a main track of the track bit TP, and a reference signal for tracking control made up of repeated flat surfaces 70 and bits 72. As mentioned above, the fp1 recording sub-track and the tracking control reference signal fp2 recording sub-track, which is formed by repeating the flat surface 73 and the bit 76, are formed respectively. The bottom surface 74b of the regeneration needle 74 is made to slide.

As shown in FIG. 11, the regeneration needle 74 is fixed to one end of the cantilever 75.
A permanent magnet 76 is fixed to the base side of the other end of the magnet 5 . The portion of the cantilever 75 to which the permanent magnet 76 is fixed is surrounded by a tracking coil 77 and a jitter correction coil 78 which are fixed to the reproducing device. The tracking coil 77 generates a magnetic field in a direction perpendicular to the direction of the magnetic field of the permanent magnet 76, and the tracking coil 77 generates a magnetic field in a direction perpendicular to the magnetic field direction of the permanent magnet 76.
5 in any one direction above the track width direction, and
Displace the object by an amount corresponding to its size.

The resonance frequency changes in response to the capacitance formed between the disk 40 and the electrode 74a shown in FIG. A resonant circuit, a circuit that applies a constant frequency to this resonant circuit, a circuit that amplitude-detects a high-frequency signal whose amplitude changes according to the change in the capacitance from the common circuit, and this amplitude-detected high-frequency signal ( playback signal)
The high frequency reproduction signal taken out from the pickup circuit 80 consisting of a circuit for pre-amplifying the FM
It is supplied to a demodulation circuit 81, where the main information signals of the main track (in this case, a digital audio signal and a digital video signal synthesized in time series) are demodulated respectively, while a part is branched and sent to a tracking servo circuit. 79.

The tracking servo circuit 79 extracts the first to third tracking control reference signals from the reproduced signal.
Frequencies of fp1 to fp3 are selected and extracted, and a tracking error signal obtained by differentially amplifying the envelope detection outputs of both reference signals fp1 and fp2 is output to the tracking coil 77. However, since the recording positional relationship of fp1 and fp2 with respect to the main track is switched every rotation period of the disk 40, the tracking polarity of the disk 40 is changed by the switching pulse generated based on the detection output of the tracking control reference signal fp3. It is switched every rotation period. In addition,
When a kick instruction signal is received at the input terminal 82, the tracking servo circuit 79 drives the tracking coil 77 so as to forcibly move the playback needle 74 by one track pitch or more in the track width direction. .

On the other hand, the demodulated digital signal taken out from the FM demodulation circuit 81 is applied to the decoder 83, where it is MFM-decoded into a time-series composite signal in the signal format shown in FIG. The beginning of a signal block is detected, the serial signal is converted to a parallel signal, and further error detection is performed. Only when an error is detected, the error code correction signals P and Q are used to correct and restore the error signal. In this way, correction and restoration are performed as necessary to ensure that there are no errors and that the signal arrangement is returned to its original order before interleaving.
Of the 16-bit 4-channel digital signals,
The 16-bit digital audio signal for each of the three channels is sent to the DA in the decoder 83.
After being converted into analog audio signals by a converter, they are output to output terminals 84, 85 and 86, respectively. The pick-up control signal is also output to a predetermined circuit (not shown) for high-speed position search and the like.

On the other hand, the digital video signal in the signal format shown in FIGS. 4 and 5, which is reproduced in time series in the fourth channel, is supplied to the scanning line number conversion circuit 87 shown in FIG. number is 625
This method will be converted to the 525-line method. Here, as described above, the digital video signal is related to image information of scanning lines in which the scanning lines of the first field and the scanning lines of the second field are alternately selected from the top of the screen, and , the scanning line number conversion code "6LMODE" in the header signal is reproduced, making it easy to convert the number of scanning lines.

As described above, the scanning line number conversion circuit 87 is a necessary circuit for a reproduction device that reproduces an input signal as an NTSC-compliant analog color video signal with 525 scanning lines.
However, it is not necessary when reproducing an analog color video signal conforming to the SECAM system or PAL system with 625 scanning lines. Of course, in this case, a changeover switch may be provided to change over the input and output of the scanning line number conversion circuit 87, and this may be changed according to the television system to be reproduced. The 525-scanning-line digital video signal serially taken out from the scanning-line converting circuit 87 is supplied to a switch circuit 88 .

Furthermore, the digital video signals sequentially and time-sequentially extracted from the decoder 83 in the signal format shown in FIG.
2 are also supplied respectively. Synchronous signal detection circuit 89
is the synchronization signal 20 shown in FIG. 4 in the header signal.
or 25 and the EOD signal, and supplies the detection signal to the control circuit 90.

However, when the synchronization signal detection circuit 89 detects the synchronization signal 20 or 25, the 5-word (or 11-word) data that comes immediately after that detects the same value as the synchronization signal 20 or 25, even if it has the same value as the synchronization signal 20 or 25. The configuration is such that it is not detected as a synchronization signal even if the synchronization signal is detected. This makes it possible to prevent header section signals other than the synchronization signals 20 and 25, and even pixel data, from being detected as synchronization signals.
The header signal detection circuit 91 discriminates each code in the header signal shown in FIG. 4 and supplies it to the control circuit 90.

The control circuit 90 receives code detection signals such as a synchronization signal detection signal and a header signal, and also detects the picture type intended by the playback device user (the picture type identification code "P, Q" ”
A signal (category number signal) specifying several types of special images identified by
These input signals are discriminated and decoded to control the scanning line number conversion circuit 87, switch circuit 88, memory write controller 92, switching circuit 97, etc. The output digital video signal of the scanning number conversion circuit 87, which is selectively outputted by the switch circuit 88, is stored in the memory 94.
and 95, and the address signal 2 shown in FIG.
1a to 24a (or 21b to 24b) (here, the number of scanning lines)
Since this is a device that reproduces 525-line analog color video signals, the address signals 23a and 24a are
(or address after scanning line number conversion specified by 23b and 24b)).

Here, the address signals 21a to 24a, 2
1b to 24b are signals that designate address numbers when writing (taking in) 2H worth of digital luminance signals and two types of digital color difference signals to the memories 94 and 95 in this embodiment, and the memory write controller 92 handles the luminance signals. and one system common to two types of color difference signals. Also memory 9
4,95 have header parts H1 to H2 shown in FIG.
The memory write controller 92 is controlled so that the pixel data group of the video signal sections V1 to V286 is written without writing the 86 and EOD signals.

Normally, reproduced pixel data is alternately written into the memories 94 and 95 one frame or one field at a time, but in this embodiment, the memory 94 designated by the write designation code "B19W" shown in FIG.
Or 95 writes reproduced pixel data within the horizontal blanking period.

Memories 94 and 95 synchronize and read out the written reproduction pixel data based on the read control signal from the memory read controller and synchronization signal generation circuit 96, and also correct jitter associated with reproduction. Here, the digital luminance signals read out from the memories 94 and 95 have a sampling frequency of 9MHz,
The first and second digital color difference signals are read out with a quantization number of 8 bits, and each has a sampling frequency of 2.25M.
Hz, quantization number 8 bits and switching circuit 9
7.

The switching circuit 97 selects and outputs the readout output of one of the memories 94 and 95 according to the switching control signal from the control circuit 90, and outputs the readout output of one of the memories 94 and 95 to the DA converter 98,
99 and 100. Here, the switching circuit 9
7 is the memory 94 or 95 designated by the read designation code "B19R" shown in FIG.
The readout output of the memories 94 and 95 is selectively outputted, and the readout output of the memory 94 and 95 is switched to the readout output of the other memory by the switching control signal supplied when the EOD signal is detected. Let's do it. The time required for switching the switching circuit 97 is normally extremely short, but when a special effect such as a fade-in is produced, the switching is performed gradually over a certain period of time (for example, 1 second).

Of the three types of digital signals that have passed through the switching circuit 97, the digital luminance signal is converted from digital to analog by the DA converter 98 and is supplied to the encoder 101 as an analog luminance signal.On the other hand, the two types of digital color difference signals are The signals are digital-to-analog converted by DA converters 99 and 100, respectively, and supplied to an encoder 101 as color difference signals (B-Y) and (R-Y). encoder 10
1 generates a color video signal compliant with the NTSC system from these three types of analog signals, a horizontal synchronization signal, a vertical synchronization signal, a color burst signal, etc. from the memory read controller and synchronization signal generation circuit 96, and outputs it to a playback output terminal. output from 102 to a color television receiver for monitor (not shown),
Here, color still images, partial moving images, etc. are displayed as supplementary information for the listener's music appreciation of the audio signals outputted from the output terminals 84, 85, and 86 and reproduced.

Incidentally, the music program and the color image played back from the disk 40 need to be played back in synchronization with each other. Since it takes a certain amount of time, it is necessary to record the digital video signal for the certain period of time before the start of displaying the image. Therefore, it is necessary to record the digital video signal from the recording start position of each music program and the digital video played from the beginning of the music program. The latter is recorded ahead of the recording start position of the signal by the predetermined period of time. Therefore, when randomly accessing the disk 40, the reproduction needle 74 is moved at high speed toward the inner circumference or outer circumference of the disk 40, and the ninth
The control signal of the signal format shown in the figure is played back and compared with the chapter code of the desired music program, and when the beginning position of the desired music program is reached, playback in any mode such as normal playback is started from there. In such cases, the digital video signal may be played back from the middle. In such a case, in the method previously proposed by the applicant, the synchronization signal existed only at the first position of the digital video signal of one field or one frame of the image, so the digital video signal reproduced from the middle of the above Although it was not possible to display the video signal, according to this embodiment, the header section can be displayed as shown in Figure 3.
Since it is placed and transmitted before the 2H digital video signal section, even if it is played from the middle, the digital video signal after the first played header section can be taken into the memory 94 or 95 and displayed. can do.

Furthermore, if you want to partially display lyrics etc. on the screen,
If you concentrate and transmit the image information of only that part,
You can quickly change that part. Similarly, a moving image can be played on a limited small screen portion of the screen. That is, the playback screen 10 shown in FIG.
When playing a moving image on a limited small screen portion 106 within 4, address signals 21a to 24a and 21b to specify the address of this small screen portion 106.
The process of transmitting pixel data successively to the header section having 24b is repeated. In Figure 13, 105
indicates the transmission position of the header section. However, as described above, this header section 105 is not displayed on the screen 104. The pixel data of the small screen portion 106 is stored in the screen 104 of the memories 94 and 95.
Since the digital video signal that displays the image is written to the memory on the side that is reading it, the written pixel data is displayed as a moving image on the small screen part 1.
Displayed on 06. In the case of partial image transmission, the transmission time varies depending on the display area, so images displayed on a small screen have a short transmission period and can be made into moving images.

To rewrite the pixel data of the small screen part above,
After reproducing one header signal, when the synchronization signal in the next header signal is reproduced, rewriting of the pixel data of that scanning line is finished, and the operation moves on to rewriting the pixel data of the next scanning line. It is configured.

In the above case, standard image transmission with 625 scanning lines was explained, but when transmitting high-definition, high-quality images, or when transmitting video using run-length codes, the image type identification code "MODE" is used. This fact is identified by the value ``, and the transmission format is also made different from that in FIG. Also, the value of the image type identification code "MODE" is discriminated and reproduced, and the output signal of the control circuit 90 controls the scanning line number conversion circuit 87 and the memory write controller 92 as necessary to format the data to be taken into the memories 94 and 95. Select. For example, when it is determined by the code "MODE" that a high-quality, high-definition digital video signal has been reproduced, the memory write controller 92 is controlled so that the memories 94 and 95 do not capture this reproduced digital video signal. (or memory 94, 9
The memory 94 compresses the above-mentioned reproduced digital video signal so as to capture it in the necessary scanning lines.
95 controls the memory write controller 92 to import the data. ). In addition, the number of scanning lines of the high-quality reproduced digital signal mentioned above has been changed from 1125 to 625.
The circuit operation of the scanning line number conversion circuit 87 may be changed to use this method or the 525-line method. In addition, transmission for one frame and transmission for one field can be mixed, and the header part remains the same at 12 words in both cases, but the value of the image information amount identification code "FR/" and the signal format are different. (2H for 1 field transmission
(The video signal part divided into 143 parts is transmitted in total), and the playback device uses this code
FL'' is discriminated and taken into memories 94 and 95 according to the format at that time.

Furthermore, even if the digital video signals supplied to the memories 94 and 95 are shifted by one word for some reason, it is corrected by reproducing the next header portion, and errors due to time shifts in words are not accumulated.

Note that the unit of division of the digital video signal recorded on the disk 40 by the method of the present invention is not limited to the above-mentioned embodiments, and in short, the unit of division of the digital video signal recorded on the disk 40 by the method of the present invention is not limited to the above-mentioned embodiment. In such cases, it is sufficient that the human eye does not perceive that the color and brightness are being switched separately (for example, pixel data with a maximum of 10 scanning lines is transmitted together with a header added to it). ). Further, in the above embodiment, the pixel data of the divided signal is assumed to be pixel data of two adjacent scanning lines (that is, pixel data of two horizontal rows of pixel groups) as shown in FIG. 14A. As explained above, as shown in Figure B, there are two vertical rows or
The pixel data may be pixel data of adjacent pixel groups up to about 10 columns. Furthermore, the digital video signal may be transmitted for one frame or one field using a total of two channels, Ch-3 and Ch-4 shown in FIG. are played back in chronological order and transmitted over a single transmission line.

In the above embodiment, the number of scanning lines of the video signal was 625, but this is because the signal recording format of a digital audio disk such as the disk 40 is common throughout the world and can be reproduced in a world-wide manner. This is to ensure that there is no shortage of information when reproducing a video signal that conforms to the standard.

In the above explanation, the case where it is applied to the disk recording method and playback device proposed earlier by the present applicant has been explained, but the present invention is not limited to this, and it can also be applied to a capacitance change reading type disk having a tracking guide groove. The present invention can also be applied to discs in which previously recorded signals are read by a light beam. In addition, if the television receiver has three primary color signal input terminals of R, G, and B, encoder 1
By using a matrix circuit instead of 01, the luminance signal Y and color difference signals (R-Y), (B-Y)
By converting the primary color signals R, G, and B into the three primary color signals and supplying them to the above input terminals separately, the television receiver can display an extremely high quality still image. Furthermore, the color difference signal recorded on the disk 40 may be a combination of (G-Y) and (RY) or (B-Y), and furthermore, an I signal,
A Q signal may be used, or three primary color signals may be used.

As described above, the digital signal reproducing device according to the present invention generates a digital luminance signal, which is a time-series composite signal of pixel data from each pixel arranged in a matrix and forming one screen, and two types of digital color difference signals. is divided into pixel data of pixel groups for each adjacent fixed number of rows or fixed number of columns, and the address number of the memory circuit to which the divided signal is taken in is indicated at least at the initial position of each divided signal. A recording medium on which a time-series composite digital video signal to which a header signal having an address signal is added is reproduced, the header signal is discriminately reproduced from the reproduced digital video signal, and the header signal is combined with the header signal. The divided signal to be subsequently reproduced is written to a predetermined address specified by the address signal in the header signal of the memory circuit, and the digital luminance signal and two types of digital color difference signals written to the memory circuit are read out simultaneously. a first digital video signal, the digital video signal having image information for one screen; When this is followed by a second digital video signal having image information to be reproduced in an area smaller than one screen, a memory circuit in which each of the divided signals in the first digital video signal is written. Accordingly, the divided signals in the second digital video signal are sequentially written based on the address signal of the header signal in the second digital video signal, and part of the image information for one screen is rewritten. , it is possible to rewrite a part of the image on the screen or display a part of the image as a moving image, and even if a word shift occurs in the reproduced digital video signal, the header signal can be rewritten every relatively short section of about a few H. Since the signal is recorded in each of the divided signals, it has many features such as being less susceptible to temporal word shifts.

[Brief explanation of drawings]

Fig. 1 is a block system diagram showing an example of the main part of the recording system of the digital signal reproduced by the device of the present invention, Fig. 2 is a diagram showing the image information part to be transmitted in the video signal, and Fig. A diagram schematically showing an example of the configuration of one frame of a video signal, FIG. 4 is a diagram showing an example of the signal format of the header signal in FIG. 3, and FIG. 5 is a diagram showing an example of the signal format of the header signal in FIG. 3. 6A and 6B are diagrams each showing an example of a method for converting the number of scanning lines from 625 to 525, and FIG. FIG. 8 is a diagram showing an example of the signal format of one block of a digital signal proposed earlier by the applicant, and FIG. 9 is a diagram showing an example of another essential part of the signal recording system. FIG. 1 shows an example of a signal format of a control signal.
0 is a system diagram showing an example of the recording device of FIG. 7, FIG. 11 is a block system diagram showing an example of the digital signal reproducing device according to the present invention, and FIG.
FIG. 13 is a partially enlarged perspective view showing an example of the sliding situation between the playback needle and the disc-shaped recording medium in FIG. FIG. 3 is a diagram showing examples of the transmission order of pixel data of a digital video signal to be reproduced by the apparatus of the present invention. 1... Video signal source, 2... TV periodic signal generator, 3... Matrix circuit, 4, 5, 6, 35...
...AD converter, 9, 10, 11, 18, 94, 9
5...Memory, 15,97...Switching circuit, 17...
...Header signal generator, 19...Digital recorder, 20, 25...Synchronization signal, 21a-24
a, 21b-24b...address signal, 30-3
2...Analog audio signal input terminal, 36...
...Control signal generation circuit, 37...Signal processing circuit, 3
9...Recording device, 40...Disc-shaped recording medium (disk), 41...Laser light source, 42, 45, 4
7... Light modulator, 49... Recording master, 59... Polarizing prism, 60... Half mirror, 61... Prism, 74... Playback needle, 74a... Electrode, 76
... Permanent magnet, 79 ... Tracking servo circuit, 80 ... Pickup circuit, 83 ... Decoder, 84 to 86 ... Analog audio signal output terminal, 87 ... Scanning line number conversion circuit, 88 ... Switch circuit, 89...Synchronization signal detection circuit, 90...
Control circuit, 91...Header signal detection circuit, 93
...Picture type specification signal, etc. input terminal, 98 to 100...
DA converter, 101... Encoder, 102...
Analog video signal output terminal, 106...Small screen portion to be rewritten, H1, H2...Header section, V1 to V286...Video signal section,
EOD...Signal transmission end signal (EOD signal).

Claims (1)

[Claims] 1. A fixed number of rows in which a digital luminance signal, which is a time-series composite signal of pixel data from each pixel arranged in a matrix and forming one screen, and two types of digital color difference signals are adjacent to each other. A header that is divided into pixel data of pixel groups for every column or a certain number of columns, and that has at least a synchronization signal and an address signal indicating the address number of a memory circuit that takes in the divided signal at the initial position of each divided signal. Reproducing a recording medium on which a time-series composite digital video signal to which a signal is added is recorded, the header signal is discriminately reproduced from the reproduced digital video signal, and the header signal is reproduced subsequent to the header signal. The divided signal is written to a predetermined address specified by the address signal in the header signal of the memory circuit, and the digital luminance signal and two types of digital color difference signals written in the memory circuit are read out simultaneously, and the DA A digital signal reproducing device that generates a reproduced color video signal of a standard television system after passing through a converter, the digital video signal comprising: a first digital video signal having image information for one screen; When the second digital video signal has image information to be subsequently reproduced in an area smaller than one screen, a memory circuit in which each of the divided signals of the first digital video signal is written, The divided signals in the second digital video signal are sequentially written based on the address signal of the header signal in the second digital video signal, and the image information for one screen is partially rewritten. Digital signal reproducing device. 2. Partial rewriting of the image information is performed by reproducing one of the header signals in the second digital video signal and then dividing the scanning line at the time when the synchronization signal in the next header signal is reproduced. 2. The digital signal reproducing apparatus according to claim 1, wherein the rewriting of the signal is completed and the operation proceeds to rewriting the divided signal of the next scanning line.