JPH0474079A - Recording device and reproducing device - Google Patents

Abstract

PURPOSE:To increase a recording channel number without changing a basic format by providing a signal superimposing means superimposing a digital audio signal on a recording portion of a digital video signal for a vertical blanking period. CONSTITUTION:Through the constitution above, an odd number field A and an even number field B are repeated. An output of a field number generating circuit 101 belongs to an odd number field for a period of the field A and a data written for a period of the field B is stored in storage circuits 103, 105, 107, 109, 111. A selection circuit 113 selects a digital audio signal of the storage circuits 105,107, 109,111 for a vertical blanking period in which an output of a line number generating circuit 102 is resident and the digital audio signal is superimposed on the output. An output of the circuit 101 belongs to an odd number field for a period of the field B the digital audio signal for the vertical blanking period is superimposed similarly to the case with the period of the field A.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a recording device and a reproducing device for digital video signals and digital audio signals.

Conventional Technology When recording digital video signals and digital audio signals on magnetic tapes, disks, etc., the recording sector is usually divided into a recording sector for digital video signals and a recording sector for digital audio signals. Digital audio signals are recorded in respective digital audio signal recording sectors.

FIG. 6 shows an example of the format of a conventional digital VTR. Dl and D2 are digital video signal recording sectors, Al, A2. A3. A4 is the recording sector of the digital audio signal, A1 is the recording sector of channel 1 of the digital audio signal, and A2 is the recording sector of the digital audio signal.
is the recording sector of channel 2 of the digital audio signal, A3 is the recording sector of channel 3 of the digital audio signal, and A4 is the recording sector of channel 4 of the digital audio signal. The digital video signal and the digital audio signal are processed separately, and the digital video signal and the digital audio signal are recorded separately in their respective sectors without being mixed.

Problem to be Solved by the Invention However, in the above method, the number of recording channels of an audio signal is determined by the format, and when increasing the number of recording channels, recording is not possible without changing the recording format. .

An object of the present invention is to provide a recording device and a reproducing device that can increase the number of recording channels of digital audio signals without changing the basic recording format.

Means for Solving the Problems In order to achieve the above object, the present invention provides a recording device for recording a digital video signal and a digital audio signal, which includes a signal for superimposing a digital audio signal in a vertical blanking period of the digital video signal. The recording apparatus includes a superimposing means and a signal processing means for processing and recording a digital signal generated by the signal superimposing means.

The reproducing apparatus also includes a signal reproducing means for processing a signal obtained by reproducing a signal recorded by the recording apparatus, and a signal processing means for separating the signal generated by the signal reproducing means into a digital video signal and a digital audio signal.

Operation With the above configuration, the present invention realizes a signal superimposing means for superimposing a digital audio signal during the vertical blanking period of a recorded portion of a digital video signal using the signal superimposing means. As a result, the digital audio signal is treated as a digital video signal and recorded in the digital video signal recording sector. Further, when reproducing a recorded signal, the signal separating means realizes means for extracting only the digital audio signal superimposed on the digital video signal. As a result, the digital audio signal treated as a digital video signal is restored to the original digital audio signal.

Example Hereinafter, the present invention will be explained in detail using Examples.

In the NTSC system, the phase of the color subcarrier at the same point on the screen is the same in four fields, so a four-field sequence is used when recording a digital video signal. In the embodiment of the present invention, in each field, line numbers 9 to 263 of field 1 and line numbers 27 of field 2 are used.
1 to 525, field 3 line numbers 9 to 263
, records line numbers 271 to 525 of field 4. The sampling frequency is 4 fsc (14.3 MHz), where fsc is the frequency of the color subcarrier, and the number of samples in each line is 768. Hereinafter, fields 1 and 3 will be referred to as odd fields, and fields 2 and 4 will be referred to as even fields.

When a digital audio signal is superimposed during the vertical blanking period, the vertical synchronization signal is repeated every two fields, so the superposition of the digital audio signal also becomes a two-field sequence.

That is, it is a repeated sequence of odd and even fields. In the case of an odd field, line numbers 9 to 20 are the vertical blanking period of the field, and line numbers 21 to 263, 384 samples, are the video data of the field. For even fields, line number 271 to line number 2
The 384th sample of 83 is the vertical blanking period of the field, and the 385th sample of line number 283 to line number 525 is the video data of the field. Among these, the signal during the vertical graphing period can be changed from the signal read from the ROM at the time of reproduction.

Therefore, the present invention provides a signal superimposition means, and by superimposing and recording a newly added digital audio signal during the vertical blanking period, it is possible to increase the number of recording channels of digital audio signals without changing the conventional recording format. shall be. In the embodiment of the present invention, the sampling frequency of the newly added digital audio signal is 48
It is kHz. On the other hand, the number of fields per second for an NTSC television signal is 80/1.001. Therefore, the number of samples to be superimposed on one field per channel of digital audio signal is 48000/(60/1.001)=800. There are 8 samples. In order to make the number of samples an integer, the digital audio signal is superimposed in a 5-field sequence.1. 2. 3. 801 samples are superimposed on the 4th field, and 800 samples (7) f' initial audio signal is superimposed on the 5th field. The bit length of the digital audio signal is 16 bits, the bit length of the digital video signal is 8 bits, and one line consists of 768 samples. Therefore, if the digital audio signal for one channel in one field period is 801 samples, then
This corresponds to a digital video signal of 01*16/8=1602 samples, and is superimposed on the 1st to 66th sample period of the 2nd and 3rd lines of the vertical blanking period. For 800 samples, soo*ie, zs
=corresponds to the digital video signal of iaoo samples,
It is superimposed on the 1st to 64th sample period of the 2nd and 3rd lines of the vertical blanking period. Therefore, in the embodiment of the present invention, a vertical blanking period of three line periods is allocated to each channel, and the digital audio signal is superimposed on the digital video signal. Therefore, for 4 channels, 12
It will be a line. Thereafter, the digital audio signals of the four newly added channels will be transferred to channel 1, channel 2, and so on. Channel 3 and channel 4.

FIG. 1 is a diagram showing the configuration of an embodiment of the recording apparatus of the present invention. In FIG. 1, a field number generation circuit 101 generates field numbers 1, 2, 3, and 4 of a four-field sequence of a digital video signal. The output of the field number generation circuit 101 is the line number generation circuit 1.
02 and the input of the selection circuit 113. Line number generation circuit 102 generates line numbers for each field of the digital video signal. That is, line numbers 1 to 263 for odd fields and line numbers 26 for even fields.
Generate 525 from 4. The output of the line number generation circuit 102 is input to the sample number generation circuit 115 and the selection circuit 113. The sample number generation circuit 115 generates sample numbers 1 to 768 for each line. The output of the sample number generation circuit 115 is input to the selection circuit 113. The field number generation circuit 116 generates the field number L2 of the 5-field sequence of the digital audio signal.
．． 3. 4. Generate 5. The output of the field number generation circuit 116 is input to the selection circuit 113. The memory circuit 103 and the memory circuit 104 are circuits that hold a notigital video signal sent at 8 bits)4fsc for one field period.

The memory circuit 103 is an odd field memory circuit, and the memory circuit 104 is an even field memory circuit. The outputs of the memory circuit 103 and the memory circuit 104 are input to the selection circuit 113.

The memory circuits 105 to 112 are circuits that hold digital audio signals sent at 16 bits and 48 kHz, and hold digital audio signals for one field period.

Memory circuits 105 and 108 are memory circuits for channel 1, memory circuits 107 and 108 are memory circuits for channel 2, memory circuits 109 and 110 are memory circuits for channel 3, and memory circuits 111 and 112 are memory circuits for channel 4. be. The outputs of the memory circuits 105 to 112 are input to the selection circuit 113. The selection circuit 113 is a field number generation circuit 1o1.
, line number generation circuit 102, sample number generation circuit 1
15. Based on the output of the field number generation circuit 116, select which of the memory circuits 103 to 112 the output is to be obtained from. The output of the selection circuit 113 is sent to the recording section 114.
As input. The recording unit 114 performs recording after processing the signal from the selection circuit 113.

FIG. 2 is a timing diagram showing the operation timing of the recording apparatus. Hereinafter, the operation shown in FIG. 1 will be explained in detail with reference to FIG. 2. In FIG. 2, W indicates a write mode in which data is held in the memory circuit, and R indicates a read mode in which data is output.

In an embodiment of the present invention, in FIG.
and repeat even field B. During field A, the output of the field number generation circuit is 1 or 3.
, that is, an odd field, and the storage circuit 103 .
105,107. Data written during the period of field B is stored in fields 109 and 111. The selection circuit 113 selects data in the storage circuit based on the outputs of the line number generation circuit 102, sample number generation circuit 115, and field number generation circuit 116. During the vertical blanking period when the output of the line number generation circuit 102 is 9 to 20, the storage circuits 105, 107 . 109°111 digital audio signals are selected and the digital audio signals are superimposed. The reading frequency at this time is 4 fsc, which is the same as the sampling frequency of the digital video signal. The data of the digital audio signal in the storage circuit 105 is superimposed on line numbers 9, 10, and 11.

FIG. 3 shows channel 1 held in the memory circuit 105.
FIG. 3 is a timing diagram showing the operation timing at which the digital audio signal of FIG. The output of the field number generation circuit 116 is 1. 2. In the case of 3°4, 86 samples of the 2nd line and 3rd line are used, so if the output of the line number generation circuit 102 is 9.10, the output of the sample number generation circuit 115 is 86 samples from 1 to 768. When the output of the line number generation circuit 102 is 11, the output of the sample number generation circuit 115 superimposes the digital audio signal on samples from 1 to 66, and the sample number generation circuit 115
A dummy signal is superimposed on samples whose outputs are 67 to 768. When the output of the field number generation circuit 118 is 5, when the output of the line number generation circuit 102 is 9.10, the output of the sample number generation circuit 115 is 1 to 76.
If the output of the line number generation circuit 102 is 11, the output of the sample number generation circuit 115 superimposes the digital audio signal on all samples 1 to 64, and the sample number generation circuit A dummy signal is superimposed on the samples whose output is 65 to 768. Similarly, data in the memory circuit 107 is stored in line numbers 12, 13, and 14 in the memory circuit 109.
The data is line number 15. 16. 17, the data in the memory circuit 111 is stored in line number 18. Superimposed on 19.20. The output of the line number generation circuit 102 is from 21 to 2.
63, the digital video signal of the storage circuit 103 is selected. The period to the field is stored in the memory circuit 104. 1
06. 108. 110. 112 is in write mode and holds the digital video signal and digital audio signal input to the storage circuit during the field A period.

During the period of field B, the output of the field number generation circuit 101 is 2 or 4, that is, an odd field, and the output of the field number generation circuit 101 is 2 or 4, that is, an odd field, and the memory circuits 104, 106, 108, 110.
Data written during the period of field A is stored in 112. As in the case of the field A period, a digital audio signal is superimposed on the 12 lines of the vertical blanking period. The data in the memory circuit 105 is stored in line numbers 271, 272, and 273.
The data in the memory circuit 109 is in line numbers 274, 275, and 276, and the data in the memory circuit 109 is in line numbers 277, 278, and 27.
9, the data in the memory circuit 11'1 is line number 280,
281 and 282. Line number generation circuit 102
When the output is from 292 to 525, the digital video signal of the storage circuit 104 is selected. During field B, the memory circuits 103, 105. 107. 109,11
1 is in the write mode, and holds the digital video signal and the digital audio signal input to the storage circuit during the field B period.

FIG. 4 is a diagram showing the configuration of an embodiment of the reproducing apparatus of the present invention. In FIG. 4, a reproducing unit 203 reproduces and processes a digital video signal recorded by a recording device, and then outputs the signal. The output of the reproduction section 203 is sent to the storage circuit 2.
04 to 213 are input. Field number generation circuit 2
01 is field number 1 of the 4-field sequence of the digital video signal. 2. 3. Generate 4. The output of the field number generation circuit 201 is input to the line number generation circuit 202 and the storage circuit control section 216. Line number generation circuit 202 generates line numbers for each field of the digital video signal.

That is, line numbers 1 to 263 of odd fields,
Generate line numbers 264 to 525 for even fields. The output of the line number generation circuit 202 is input to the sample number generation circuit 214 and the storage circuit control section 216. The sample number generation circuit 214 generates sample numbers 1 to 768 for each line. Sample number generation circuit 21
The output of No. 4 is input to the storage circuit control section 216. The field number generation circuit 215 generates field numbers 1, 2, 3 of the 5-field sequence of the digital audio signal.
．． 4. Generate 5. Field number generation circuit 21
The output of 5 is input to the storage circuit control section 216. The storage circuit control unit 216 controls writing and reading of the storage circuits 204 to 213 based on the outputs of the field number generation circuit 201, line number generation circuit 202, sample number generation circuit 214, and field number generation circuit 215. The memory circuit 204 and the memory circuit 205 are 8-bit 4fs
This is a storage circuit for a digital video signal with a superimposed digital audio signal reproduced by c. Memory circuit 20
4 holds the odd field of the digital video signal, and the storage circuit 205 holds the even field of the digital video signal. Memory circuits 206 to 213
is a storage circuit for the digital audio signal superimposed on the vertical blanking period of the digital video signal;
Holds the data sent with bit 4fsc. Memory circuits 2013 and 207 are memory circuits for channel 1, memory circuits 208 and 209 are memory circuits for channel 2, memory circuits 210 and 211 are memory circuits for channel 3, and memory circuits 212 and 213 are memory circuits for channel 4. The storage circuits 208, 208, 210, and 212 are in write mode when the field is an odd number, and the captured digital audio signal is read out at 16 bits and 48 kHz to become a normal digital audio signal.

FIG. 5 is a timing chart showing the operation timing of the playback device. Hereinafter, the operation shown in FIG. 4 will be explained in detail with reference to FIG. In the embodiment of the present invention, in FIG. 4, an odd field C and an even field D are repeated, similar to the recording apparatus. Reading of written fists from the memory circuits 204 to 213 is controlled as follows.

During the period of field C, the output of the field number generation circuit 201 is 1 or 3, that is, an odd field, and the output of the field number generation circuit 201 is 1 or 3, that is, an odd field, and the output of the field number generation circuit 201 is 1 or 3, that is, an odd field.
12 is in write mode.

When the output of the line number generation circuit 202 is from 9 to 263, the digital video signal is held in the storage circuit 204. Also, the line number generated by the line number generation circuit 202 is 9. 10.11, 1 is stored in the memory circuit 206.
2. 13.14, it is stored in the memory circuit 208, 15.
When 18.17, 18, 19.2 is stored in the memory circuit 210.
When the value is 0, the portion where the digital audio signal is weighted is determined from the output of each sample number generation circuit 214 in the storage circuit 212, and only the data of that portion is written. During the field C period, the digital video signal held in the storage circuit 205 and the digital audio signal held in the storage circuits 207, 209, 211, and 213 during the field D period are read out.

During the period of field D, the output of the field number generation circuit '201 is 2 or 4, that is, an even field, and the memory circuits 205, 207, 209, 211,
213 becomes the write mode.

When the output of the line number generation circuit 202 is from 272 to 525, the digital video signal is held in the storage circuit 205. When the line number generated by the line number generation circuit 202 is 271, 272, 273, it is stored in the storage circuit 206, and when it is 274, 275.276, it is stored in the storage circuit 208.
277.2'78°279, the memory circuit 210
280, 281, and 282, the portion where the digital audio signal is superimposed is determined from the output of the sample number generation circuit 214, and only the data of that portion is written into the storage circuit 212. During the period of field D, the digital video signal held in the storage circuit 204 during the period of field C and the storage circuits 206, 208, 2
The digital audio signal held at 10, 212 is read out.

DETAILED DESCRIPTION OF THE INVENTION As described above, the present invention has realized an apparatus that superimposes a digital audio signal on a vertical blanking period of a recorded portion of a digital video signal and records it as a digital video signal. As a result, it becomes possible to increase the number of recording channels of digital audio signals without changing the conventional recording format or increasing the amount of hardware.

As described above, the present invention not only increases the number of recording channels of dinotal audio signals, but also has excellent features in that it is very easy to put into practical use because there is no need to change the format. Therefore, it is particularly effective for digital VTRs that record both digital video signals and digital audio signals, and the practical effects of the present invention are great.

For convenience of explanation, the explanation has been given using an NTSC digital video signal recording and reproducing apparatus as an example, but it goes without saying that the present invention is also effective for PAL and other broadcasting systems.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a recording device according to the present invention, FIG. 2 is a timing chart for explaining the operation of the device in FIG. 1, and FIG. 3 is an example of superimposing digital audio signals of channel 1. Timing chart, FIG. 4 is a block diagram showing the configuration of the playback device according to the present invention, FIG.
This figure is a timing chart for explaining the operation of the apparatus shown in FIG. 4, and FIG. 6 is a diagram showing a tape former of a conventional digital video apparatus. 101, 11゛Ei, 201. 215... Field number generation circuit, 102, 202... Line number generation circuit, 103-112, 204-213
...Memory circuit, 113...Selection circuit, 11
4...Recording unit, 115.214...Sample number generation circuit, 203...Reproducing unit, 216...Storage circuit control unit. Name of agent: Patent attorney Shigetaka Awano

Claims (4)

[Claims] (1) A recording device for recording a digital video signal and a digital audio signal, which includes a signal superimposing means for superimposing a digital audio signal during a vertical blanking period of the digital video signal, and a digital signal generated by the signal superimposing means. A recording device comprising signal recording means for processing and recording. (2) a signal reproducing means for reproducing and processing the signal recorded by the recording device according to claim 1; and a signal separating means for separating the signal generated by the signal reproducing means into a digital video signal and a digital audio signal. A playback device equipped with (3) A first storage circuit that stores digital video signals of odd fields, and a second storage circuit that stores digital video signals of even fields.
a third storage circuit group that divides a plurality of channels of digital audio signals corresponding to the odd fields and the even fields for each channel, and stores the digital audio signals corresponding to the odd fields, respectively; a fourth storage circuit group that stores digital audio signals corresponding to the even fields, a first field number generation circuit that generates field numbers of a four-field sequence of the digital video signal, and the first field number generation circuit. a line number generation circuit that generates a line number for each field of the output of the circuit; a sample number generation circuit that generates a sample number for each line of the output of the line number generation circuit; and a field of the five-field sequence of the digital audio signal. a second field number generation circuit that generates a number; and the first storage circuit and the second storage according to the outputs of the first field number generation circuit, the line number generation circuit, and the sample number generation circuit. select the output of the circuit, and select the third storage circuit group and the A recording device comprising: a selection circuit that sequentially selects outputs of a fourth storage circuit group; and a recording section that processes the outputs of the selection circuit and records them on a recording medium. (4) a playback unit that plays back and processes the signal recorded by the recording device according to claim 3; a fifth storage circuit that stores the odd field digital video signal output from the playback unit; a sixth for storing the output even field digital video signal;
a seventh storage circuit group that stores digital audio signals corresponding to odd fields output from the reproduction section, and an eighth storage circuit group that stores digital audio signals corresponding to even fields output from the reproduction section, respectively. a group of storage circuits; a third field number generation circuit for generating field numbers of a four-field sequence of the digital video signal; and a line number generation circuit for generating line numbers for each field of the output of the third field number generation circuit. a fourth field number generation circuit for generating a sample number for each line of the output of the line number generation circuit; a fourth field number generation circuit for generating a field number for a five-field sequence of the digital audio signal; Writing and reading of the fifth storage circuit and the sixth storage circuit are performed by the outputs of the third field number generation circuit, the line number generation circuit, and the sample number generation circuit. a memory circuit control unit that controls writing and reading of the seventh memory circuit group and the eighth memory circuit group based on the outputs of the line number generation circuit, the sample number generation circuit, and the fourth field number generation circuit; A playback device equipped with