JPH0743880B2 - Digital signal recording / reproducing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital signal recording / reproducing apparatus such as a video tape recorder and an audio tape recorder capable of digital audio recording.

2. Description of the Related Art In recent years, digital tape-capable video tape recorders (VTRs) or audio tape recorders (ATs)
R) is being developed and various types of devices are being developed. Unifying the interfaces of various digital devices like this,
The interface standard described below aims to effectively use software by exchanging signals with each other as they are digital signals without degrading the quality.

AES (Audio Engineering Society) and EBU (Europe Br
oadcast Union), the standard has been debated, and currently IEC and AN
The digital audio interface (DAIF) standard that is being applied to SI is the world's standard for digital audio for professional use. An outline of part 1 is shown in FIGS. 3, 4, and 5.

FIG. 3 shows the structure of the sub-frame unit which is the minimum unit of the interface signal format. The first 4 bits are the 4th
The preamble part with three different patterns shown in the figure "Z", "Y", "X", the next 4 bits are the auxiliary data area,
Next is an audio parity data having a 20-bit slot, then a 1-bit valid / invalid flag, a user data area, a channel status area, and finally an even parity flag valid for data excluding the preamble portion.

FIG. 4 shows the structure of a stereo signal frame composed of two subframes. Each frame circulates with a period of 192.

FIG. 5 shows the channel status word portion shown in FIG.
It is shown in the form of being collected in units of 192 subframes, and the allocation shown in the figure is performed in units of 24 bytes. Byte 0-
Although not shown in detail in the drawing, 3 is assigned samble frequency information and various status information, and 7-bit ASCII data with odd parity is assigned to bytes 6-9 and 10-13 and arbitrary character information is put on the bytes. In addition, bytes 14-17 and bytes 18-21 are assigned 32 bits of binary data and can carry tape address and time information. A byte block validity flag is assigned to the byte 22, and a CRCC code for the data of the bytes 0 to 22 is assigned to the last byte 23. With respect to the usage of such information, there is a part where the degree of freedom of the user is large, such as the user data area, and there is a lot of room to consider an effective usage.

On the other hand, as a problem from the standpoint of using VTR and ATR from the past, VTR and ATR are especially
Regardless of the generation management of recorded tapes, that is, identification of original tapes, edited master tapes, copy tapes dubbed, etc., the world where analog type equipment whose quality deteriorates significantly with each generation Then it is important. Conventionally, the generation management of this tape was manually entered in the recording space of the tape reel or cassette, and even the package.

However, in the conventional method, since the generation management of the VTR and ATR tapes relies on human beings, it is very complicated such as mistakes or omissions in writing, or reels or packages being replaced. There was a problem.

In view of the above problems, it is an object of the present invention to automatically record the history of recorded equipment on a tape and accurately realize generation management without burden.

Means for Solving the Problems In order to solve the above problems, the present invention provides a device number unique to a device with a digital audio interface (DAI).
F) means for allocating the channel status field of the format, means for recording the device number received through the interface in the user data area together with audio data during dubbing recording, and reproduction data from the user data area during reproduction. It is composed of means for allocating and transmitting to the user data fold of the interface format.

Effect The present invention, with the above-mentioned configuration, can record and reproduce the history from the source side device number to the original recording device number inherited by dubbing on the tape along with the audio signal at the time of dubbing recording, and automatically manage the generation. I can do it.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic block diagram of a digital recording / reproducing apparatus according to an embodiment of the present invention. In this case, a VTR capable of recording analog video and digital audio will be described as an example.

In the figure, 1 is an analog video signal input terminal, 2 is an analog video signal output terminal, 3 is an analog audio input terminal,
4 DAIF input terminal, 5 video signal output terminal, 6 DAIF output terminal, 7 video recording circuit, 8 video reproducing circuit, 9 AD converter for audio signal, 10 DAIF input circuit, 11 audio DA converter for signal, 12 DAIF output circuit, 13 input selector switch, 14 video signal recording / playback selector switch,
15 is a field memory for audio signal processing, 16 is an audio signal recording circuit, 17 is an audio signal recording / playback switch, 18 video / audio switching switch, 19 is a recording / playback head, 20 is an audio signal playback circuit, and 21 is Field memory for audio signal processing, 22 device ID switch for setting unique device number, 23 COD (Channel Origin Data) register, 24 channel status register, 25 recording user data register, 26 user ID generation A circuit, 27 is a user ID separation circuit, 28 is a user data register on the reproducing side, 29 is a changeover switch, and 30 is a display element for displaying the contents of user data.

FIG. 2 is a table showing an example of allocation contents of user ID signals according to the embodiment of FIG.

Next, the operation will be described with reference to the drawings.

The analog video signal input from the terminal 1 is subjected to recording signal processing by the video recording circuit 7. Since the processing content is not directly related to the present invention, it will not be described in detail, but if it is a component recording type VTR, decoding processing from an NTSC signal, time division compression processing, FM modulation and the like are included. The generated recording signal is selected by the recording / reproducing changeover switch 14, and the recording / reproducing head 19 is driven via the video / audio changeover switch 18. The reproduced video signal passes through the switches 18 and 14 in reverse and is guided to the video reproduction circuit 8. The video reproduction circuit 8 performs waveform shaping processing of the reproduction signal, demodulation processing, time base correction and expansion by TBC, and finally performs encoding to the NTSC signal.
Output from terminal 2.

The configuration shown in FIG. 1 is an example in which one recording / reproducing head is used to record an analog image and digital audio compressed in a field unit by area division. However, this head mechanism and the image signal processing method are used. The configuration has no direct relation to the present invention and is merely an example for explanation.

The analog voice signal is input from the terminal 3 and converted into a digital signal by the AD converter 9. When the DAES signal of the AES / EBU standard is input from the terminal 4, the DAIF input circuit 10 detects the subframe synchronization shown in FIGS. 3 and 4, and demodulates the data portion that has been subjected to the biphase modulation. Bit synchronization of. The input digital audio signal separated by the DAIF input circuit 10 is input to the switch 13. The switch 13 selects either analog input or digital input according to the input selection mode. Normally, an analog input is used when input as an original source from a microphone or a mixer, and a digital input mode is selected when dubbing. The selected digital audio signal is once written in the field memory 15 on a field-by-field basis.

On the other hand, the device ID switch 22 is a switch that can set a device unique number, and can set an alphanumeric code such as VRO5 as shown in the example of FIG. This can correspond to the alphanumeric channel origin data (COD) in bytes 6-9 of the channel status data shown in FIG. COD
The register 23 scans the output of the device ID switch 22 and passes the silyl output to the user data register 25 and the channel status register 24 on the recording side. Although not shown, the channel status register 24 also reads other channel status information such as address and time code information, and outputs a serial output. User data register 25
It is also possible to rearrange the user data in order to record the ID number and the input user data together on the tape and display the result on the display element 30.

That is, as will be described later, it is possible to display a history of what kind of device the input source was dubbed, and which device made the original recording. The output of the user data register 25 is input to the user ID generation circuit 26 and is associated with the user ID signal recorded on the tape.

FIG. 2 shows an example thereof.

The user ID signal uses a blank portion provided in advance on the tape or a surplus portion generated between the sampling frequency (the number of audio samples in one field period) and the number of data blocks due to the format configuration. If there is a user ID area from ID0 to IDn, the device number on the source side input to ID0 as shown in the table is
Two generations ago, it will be a stack structure with the original. The original IDn is fixed, and the others are updated by repeating dubbing. It is said that the practical number of times of dubbing is about 5 times, and that is enough even for the depth of the stack.

The generated user ID signal is written in the field memory 15 via the data bus, and thereafter, addition of an error correction signal, interleaving, and modulation are performed by the voice signal recording circuit 16 similarly to voice data. The generated recording signal drives the recording / reproducing head 19 via the switches 17 and 18.

The playback operation of the audio signal passes through the switches 18 and 17 in reverse,
After being subjected to waveform processing, demodulation, and time axis correction by TBC in the audio signal reproduction circuit 20, it is once written in the field memory 21.
After that, the data read from the memory is subjected to error correction processing in the audio signal reproducing circuit 20, and is written in the field memory 21 again. The corrected data is read again from the field memory 21, converted from the DA converter 11 into an analog signal, and output from the terminal 5. After the error correction of the user ID signal recorded together with the voice data is completed, the user ID signal is read out from the field memory 21 and only the user ID portion is extracted by the user ID separation circuit 27 and the user data register 28
Passed to. In the user data register 28, only the necessary information selected from the information in the user data area can be sent to the display element 30 for display.

Also, the reproduced user data is mixed with the channel status information via the switch 29, and the DAIF output circuit
At 12, mixing with audio data, addition of a preamble, a valid flag, etc., and calculation of parity are performed, and then modulated and output from the terminal 6.

If you operate a VTR device with a unique device number with the above-mentioned configuration in a network system, the history of the recorded device will be automatically recorded on the tape even if you repeat the editing dubbing operation. You can record.
Generation management can be realized accurately and with less burden.

Effects of the Invention As described above, according to the present invention, it is possible to accurately and unconsciously realize generation management of VTR and ATR tapes, and in particular, an image requiring generation management remains analog.
In VTR, the effect is great.

[Brief description of drawings]

FIG. 1 is a block diagram of a digital signal recording / reproducing apparatus in an embodiment of the present invention, FIG. 2 is a diagram for explaining the contents of a user ID signal according to the embodiment shown in FIG. 1, and FIG. 3 is an AES / EBU standard. Sub-frame mechanism in the DAIF format of the 4th,
FIG. 5 is a frame configuration diagram of the format shown in FIG. 3, and FIG. 5 is a format configuration diagram of channel status data in the format shown in FIG. 10 …… DAIF input circuit, 12 …… DAIF output circuit, 16 …… Voice signal recording circuit, 20 …… Voice signal playback circuit, 22 …… Device ID
Switch, 23 …… COD register, 24 …… Channel status register, 25 …… User data register, 26 ……
User ID generation circuit, 27 ... User ID separation circuit, 28 ...
… User data register.

Claims (1)

[Claims] 1. An audio tape recorder device and a video tape recorder device capable of digital audio recording, comprising an AES / EBU digital audio interface, which are detected from a channel status field in a digital audio interface signal input during recording. Addition means for superimposing and adding device information unique to the recording device on the copy history information so far, allocating means for allocating the newly created copy history information to the control information area in the digital audio recording format, and control during reproduction. Extraction means for extracting the copy history information recorded in the information area, inserting means for inserting the extracted copy history information into the channel status field of the digital audio interface signal, input signal at the time of recording and output signal at the time of reproduction Replication history A digital signal recording / reproducing apparatus comprising display means for displaying.