JPH0619908B2 - Recording / reproducing method and apparatus - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing method and apparatus for recording voice as a digital signal, and more particularly to a helical scan type magnetic recording / reproducing method and apparatus (hereinafter referred to as VTR). Is described).

[Conventional technology]

FIG. 4 is a block diagram of a recording system signal processing of a conventional Hi-Fi VTR, which is a video signal and an audio signal (audio signal).
Shows the recording system of. In the figure, 11 is a Y / C separation circuit that separates a luminance signal (Y signal) and a color signal (C signal), 12 is a synchronization separation circuit that generates a synchronization signal from the Y signal, and 13 is a low frequency signal of the C signal. A low-frequency conversion circuit for frequency-converting to a frequency band, an FM modulation circuit 14 for FM-modulating a Y signal,
Reference numeral 50 is an adder circuit, 15 is a recording amplifier, and 16 is a head. Reference numeral 17 is a noise reduction circuit.

FIG. 2 is a track pattern configuration diagram on a tape of a conventional VTR. In the figure, 21 is an audio track R, 22 is an audio track L, 23 is a video track, and 24 is a control track.

Next, the operation will be described. The video signal is first separated into a Y signal and a C signal by the Y / C separation circuit 11, and the Y signal is FM-modulated by the FM modulation circuit 14 while being synchronized with the C signal by the synchronization separation circuit 12. Further, the C signal is converted into the low frequency by the low frequency conversion circuit 13, both of these signals are added by the addition circuit 50 and sent to the recording amplifier 15.
The data is recorded on the magnetic tape by the head 16.

On the other hand, for the audio signal, first, the noise reduction circuit 1
Noise is removed by 7, and then FM modulation is performed in the FM modulation circuit 14, and the L channel signal and the R channel signal are added and sent to the recording amplifier 15 for recording by the head 16.

The video signal is video track 2 on the track pattern.
3 is recorded one field at a time, and the audio signal is recorded in the same depth. The audio signal in this case is an analog signal, and the audio signal input at the time of recording the video signal is simultaneously recorded at the same time.

[Problems to be solved by the invention]

The conventional Hi-Fi VTR is configured as described above, and since the audio signal is analog recording, there is no problem in synchronizing with the video signal. However, when attempting to digitally record an audio signal, it is necessary to consider the synchronization with the video signal or the relationship between the number of samples and the sampling frequency, and it is not possible to digitally record an audio signal with a conventional VTR.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a recording / reproducing method and apparatus capable of recording an audio signal as a digital signal and also instructing how to synchronize at the time of recording. To do.

[Means for solving problems]

The present invention is a recording / reproducing method and apparatus for recording / reproducing a digital audio signal and a video signal, and at the time of recording, an analog audio input signal is determined based on whether it is synchronized with the recorded video signal or asynchronous. The first step of digitizing and / or the second step of externally inputting a voice signal which has already been digitized, and / or the first step of arranging the digital voice signal in a predetermined format. Of the digital audio signal output by the step 2 or the second step, the signals are arranged and reproduced so that the format includes identification information for identifying whether the digital audio signal is synchronous or asynchronous with the video signal to be recorded. Sometimes, the video signal and the digital audio signal are identified by the identification information included in the format. Alternatively, it is intended to obtain a recording / reproducing method characterized by identifying asynchronism and obtaining a sound output according to the identified synchronization or asynchronousness, and a recording apparatus and a reproducing apparatus for implementing this recording / reproducing method. .

[Action]

In the recording / reproducing method and apparatus of the present invention, it is possible to record the digital audio signal in synchronization with the video signal at the time of recording, and at the time of reproduction, the synchronization or asynchronous with the video signal is identified from the identification information. It is possible to judge, and it is possible to reproduce the audio output according to the synchronization or the asynchronous.

Further, in the recording apparatus of the present invention, it is possible to record the digital audio signal by distinguishing between synchronous and asynchronous with the video signal.

Further, in the reproducing apparatus of the present invention, it is possible to judge the synchronization or the asynchronism with the video signal from the identification information, and it is possible to reproduce the audio output according to the synchronization or the asynchronism.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, the same symbols as those in FIG. 4 indicate the same or corresponding portions. Reference numerals 51L and 51R are analog audio signal input terminals to which L channel and R channel analog audio signals are input respectively, and 52L and 52R are digital audio signal input terminals to which L channel and R channel digital audio signals are respectively input. 1
8 synchronizes the analog audio signal with the video signal,
Alternatively, an A / D conversion circuit that performs A / D conversion asynchronously, 19
Is a formatting circuit for arranging the digital audio signal from the A / D conversion circuit 18 or the digital audio signal from the digital audio signal input terminal 52 according to a predetermined format, and 20 is an error correction coding (ECC) circuit.

FIG. 3 shows a data array of a digital audio signal deeply recorded in one video field section, 31 is a preamble part, 32 is a data block, and 33 is a postamble part. In the data block 32,
34 is a synchronizing signal, 35 is an identification signal, 36 is a data block address, 37 is a parity signal, and 38 is digital audio data or an error correction code. In the identification signal 35, 39 is an identification code and 40 is a field address.

Next, the operation will be described. Since the recording of the video signal is the same as the conventional one, it is omitted.

The audio signal is noise-removed by the noise reduction circuit 17, and then the Y signal of the video signal is separated from the sync separation circuit 1.
The synchronizing signal generated in 2 is converted into a digital signal by the A / D conversion circuit 8 while being synchronized with the video signal or asynchronously, and sent to the formatting circuit 19.

Further, when an already digitized audio signal is input from the outside, it is difficult to synchronize the digital audio signal and the video signal, and therefore, they are sent to the formatting circuit 19 as they are without synchronization.

The formatting circuit 19 arranges the data according to a predetermined format, the ECC circuit 20 performs error correction coding, and the data is sent to the recording amplifier 15 and sent to the head 16.
Recorded in. In this formatting circuit 19,
Data block address 3 in addition to the array of L and R signals
6, the synchronization signal 34, the identification signal 35, etc. are also added.

Here, the sampling frequency of the audio signal is generally 48.
There are two types, KHz and 32KHz, and the field frequency is N.
Consider the case of 60 × 1000 / 1001Hz in the TSC system. 1
The number of samples to be recorded in the field is 4 in case of the synchronous method.
At 8KHz it will be 800/4/5 and at 32KHz it will be 533/13/15. Therefore, in any case, the total number of data can be an integer with 15 fields. Here, in the present embodiment, it is assumed that the synchronous / asynchronous discrimination is performed by using the field address in the signal format, and since the total number of data can be an integer in 15 fields as described above, it is synchronized with the video signal. In the case of 1, the repetition of 0 to E is written as the field address 40, and in the case of asynchronous, the repetition of 0 to F is written as the field address 40. By doing so, it is possible to distinguish between synchronous and asynchronous depending on whether or not the field address "F" exists during reproduction.

The identification code 39 in the data block 32 can be used to identify whether the sampling frequency is 48 KHz or 32 KHz, whether emphasis is applied, tape speed, etc. Good.

In the above embodiment, the field address is 0 to
Synchronous / asynchronous is identified by using E or 0 to F, but if the field frequency is PAL / SECAM system multiple of 50Hz and the video signal and the audio signal are synchronized, the data is stored in each field. Complete. Therefore, in the case of this PAL / SECAM system, the case of asynchronous is N
As in the case of the TSC method, 0 to F may be repeated, and in the case of synchronization, it may be repeated from 0 to 7 so that it can be distinguished from this. Whether MSB is always 0 or not is used to distinguish between synchronous and asynchronous. You can

Also, in the above embodiment, synchronization is performed by the field address,
Although the asynchronous identification is performed, the identification code portion 39
The identification code may be directly written in or may be identified by other information.

Further, the arrangement order of the data does not need to have a block address next to the identification signal, and may be reversed, or may be handled at the same level as the data. The number of data and the number of bytes may be arbitrary.

〔The invention's effect〕

As described above, according to the recording / reproducing method and apparatus of the present invention, at the time of recording, the first step of digitizing the analog audio input signal based on the discrimination as to whether the video signal to be recorded is synchronized or asynchronous. And / or one or more of the second steps of inputting an already digitized audio signal from the outside, and the first step of arranging the digital audio signal in a predetermined format.
Of the digital audio signal output by the step 2 or the second step, the signals are arranged and reproduced so that the format includes identification information for identifying whether the digital audio signal is synchronous or asynchronous with the video signal to be recorded. Sometimes, by identifying the synchronization or asynchronism between the video signal and the digital audio signal from the identification information contained in the format, and obtaining the audio output according to the identified synchronization or asynchronism, the digital audio is recorded at the time of recording. It becomes possible to record the signal by distinguishing the synchronization or the asynchronization with the video signal, and at the time of reproduction, the synchronization or the asynchronism with the video signal can be judged from the identification information, and the audio output according to the synchronization or the asynchronization can be reproduced. .

Further, the recording apparatus for carrying out the recording / reproducing method of the present invention can record the digital audio signal by distinguishing between synchronous and asynchronous with the video signal.

Further, in order to carry out the recording / reproducing method of the present invention, the reproducing apparatus can judge the synchronization or the asynchronism with the video signal from the identification information at the time of reproducing the digital audio signal, and can reproduce the audio output according to the synchronization or the asynchronism.

[Brief description of drawings]

FIG. 1 is a diagram showing a recording system of a recording / reproducing method and apparatus according to an embodiment of the present invention, FIG. 2 is a diagram showing a track pattern structure on a tape of a VTR, and FIG. 3 is a deep layer recording in one video field section. FIG. 4 is a data array diagram of the generated digital audio signal, and FIG. 4 is a diagram showing a recording system of a conventional Hi-Fi VTR. 12 ... Sync separation circuit, 18 ... A / D conversion circuit, 19
........ Formatting circuit, 32 ... Data block, 35 ... Identification signal, 38 ... Digital audio data or error correction code, 51 ... Analog audio signal input terminal, 52 ... Digital audio signal input terminal. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (3)

[Claims] 1. A recording / reproducing method for recording / reproducing a digital audio signal and a video signal, wherein at the time of recording, an analog audio input signal is digitalized based on whether it is synchronized or asynchronous with the video signal to be recorded. First to turn
And / or a second step of externally inputting a voice signal which has already been digitized, and the first step or the first step when arranging the digital voice signal in a predetermined format. The signals are arranged so that identification information for identifying whether the digital audio signal output in step 2 is synchronous or asynchronous with the recorded video signal is included in the format, and included in the format during reproduction. A recording / reproducing method, characterized in that the synchronization or asynchronism between the video signal and the digital audio signal is identified from the identified information, and an audio output corresponding to the identified synchronization or asynchronous is obtained. 2. A recording device for carrying out a recording / reproducing method, wherein the analog-digital conversion means digitizes an analog audio input signal based on the distinction between being synchronized with a recorded video signal or being asynchronous. And / or one of the input means for externally inputting the audio signal which has already been digitized, and the analog-digital converting means or the input means when the digital audio signal is arranged in a predetermined format. And a signal arranging means for causing the format to include identification information for identifying whether the digital audio signal is synchronous or asynchronous with the video signal to be recorded. 3. A reproducing apparatus for carrying out a recording / reproducing method, wherein the video signal and the digital audio signal included in a predetermined format in which the digital audio signal is array-recorded at the time of reproducing the digital audio signal. The present invention is characterized by comprising identification means for identifying whether the video signal and the digital audio signal are synchronous or asynchronous from the synchronous or asynchronous identification information, and obtaining an audio output according to the synchronous or asynchronous identified by the identifying means. Playback device.