JPH01102779A - Digital signal recorder - Google Patents

Abstract

PURPOSE:To amend the lack of an audio signal even when a tape is longitudinally flawed in the middle part by recoding a video signal of one field or one frame to be divided into plural tracks and recording an audio signal at a prescribed interval as well. CONSTITUTION:The video signal of one field or one frame recorded in the tape 1 is divided into plural tracks to be as recorded, while the audio signal is recorded at a prescribed interval. One field or one frame is divided into plural tracks, e.g., five or ten tracks respectively. Then, in case of one field, four tracks with the video signal and the remaining one track with the audio signal are respectively recorded on a compressed time base, and in case of one frame, nine tracks with the video signal and the remaining one track with the audio signal are respectively recorded on a compressed time base. By this method, since the whole one track is filled with the audio signal, even when the tape is flawed longitudinally in the middle part, the lack of the audio signal can be amended.

Description

[Detailed description of the invention] The invention will be explained in the following order.

A. Field of industrial application B. Essentials of the invention C. Prior art D. Problem to be solved by the invention E. Means for solving the problem (Fig. 1) ) G2 circuit operation (Figures 2 to 7) Effects of the invention A Industrial field of application This Q invention divides a video signal for one field or one frame into several tracks. The present invention relates to a digital signal recording device suitable for use in so-called segment recording type V'rR and the like.

B. Summary of the Invention This invention is a segment recording type digital (A recording device) in which a video signal of one field or one frame is divided into a plurality of tracks and recorded, and an audio signal is recorded at predetermined intervals. By doing so,
Even if there is a longitudinal scratch in the center of the tape, it is possible to correct missing audio signals with I:11 capability, and there is no need to record data signals such as serve codes over many tracks during high-speed searches. It is.

C. Prior Art In general, digital VTRs have a large amount of data, so unlike analog VTRs, one field cannot be recorded in one track, and so-called segment recording is performed.

An example of a conventional segment recording type VTR is, for example, a 4:2:2 component V'l'R.

This V'rR tape format records the video signal by dividing it into 10 tracks per field.
As shown in the figure, four channels of audio signals are recorded in the center of each track in a time-division manner.

D Problems to be solved by the invention By the way, in the case of the conventional digital VTR as mentioned above,
The disadvantage is that when a longitudinal scratch occurs in the center of the tape, the audio signal in that area is completely damaged.

In addition, if data such as subcodes is placed in a part of each track in the same way as audio signals, and it is necessary to pick up that data during a high-speed search, there may be times when it cannot be picked up (not traced) by just putting it in one track. Therefore, the disadvantage is that the same data must be input for several seconds, ie, over many tracks.

This invention was made in view of the above points, and it is possible to correct missing audio signals even if there is a longitudinal scratch in the center of the tape, and it is also possible to correct missing audio signals from a large number of tracks, which provides information for high-speed searching. To provide a digital signal recording device that does not require recording over an entire area.

E. Means for Solving the Problems The recording apparatus according to the present invention is configured to record one field or one frame of video signals divided into a plurality of tracks, and to record audio signals at predetermined intervals.

Divide the 1'' working l-field or l-frame into a number of tracks, for example 5 or 10 trunks, respectively.

In the case of one field, for example, there are four video signals,
In the remaining one, the audio signal is compressed on the time axis and recorded, and in the case of one frame, for example, the video signal is recorded on nine lines, and the audio signal is compressed on the time axis and recorded on the remaining one. As a result, since the audio signal is contained in the entire trunk, even if there is a longitudinal scratch in the center of the tape, it is possible to correct the missing audio signal. Furthermore, by recording a data signal such as a subcode, which serves as information during a high-speed search, on one track together with an audio signal, there is no need to record the same data signal over a large number of tracks as in the past.

G. Example Hereinafter, an example of the present invention will be described in detail based on FIGS. 1 to 7.

01 Circuit Configuration Figure 1 shows the circuit configuration of this embodiment. In the figure, (1) is a magnetic tape, (2A) and (2B) are a - set of rotating heads, and these rotating heads are Head (2A
) and (2B) are provided facing each other at an angular interval of 180° around the rotating drum. Further, the tape (1) is applied to the upper drum and the lower drum in a predetermined angular range, for example, about 180 angular ranges.
It is wound diagonally in the angular range of °.

Heads (2A) and (2B) are connected to fixed contacts a and b of switch (3), respectively. The switch (3) is switched by a switching signal generated based on a PC pulse or the like supplied from a pulse generator (not shown) to a terminal (5) from the system controller (4). switch (3)
The movable contact C of is connected to the movable contact C of the swing (6). The switch (6) is switched by a recording/playback mode switching signal formed based on operation information supplied from the operation unit (not shown) to the terminal (7) from the system controller (41), and is fixed in the recording mode. It is connected to the contact A side, and in the playback mode, it is connected to the fixed terminal A side.

(8) is an input terminal to which a video signal is supplied, and the video signal from this input terminal (8) is converted from an analog signal to a digital signal by an A/D conversion circuit (9), and then sent to an interleaving circuit (10). The data is sorted here. This rearranged data is added with parity and error correction code by an error correction code encoder (11), compressed in the time axis by a time axis compression circuit (12), and passed through the fixed contact a side of the switch (13) to the channel. A coding circuit (14) is supplied. Then, modulation and coding is performed to convert the signal into a signal with properties suitable for high-density magnetic recording, and a synchronization code is added to achieve frame synchronization and word synchronization using a synchronization addition circuit, which is not shown in the history. The signal is supplied to the fixed contact a side of the switch (6) via the recording amplifier (15).

In addition, (16) and (17) have input terminals to which audio stereo signals are supplied, for example, input terminal (1
6) is supplied with the left channel signal, and the input terminal (17
) is supplied with the right channel signal. These signals are converted from analog signals to digital signals by A/D conversion circuits (18) and (19), respectively, and then the data is rearranged by an increment circuit (20). This rearranged data is added with parity and error correction code by an error correction code encoder (21), and a time axis compression circuit (
22), and is supplied to the channel coding circuit (14) which passes through the fixed contact side of the switch (13), and after being processed in the same manner as described above, is sent to the switch (6) via the recording amplifier (15) ) is supplied to the fixed contact a side.

Further, the synchronization signal included in the video signal from the input terminal (8) is separated by the synchronization circuit (23), and based on this, a video/audio switching signal is formed, and the switch (1)
3). Therefore, when recording the video signal from the input terminal (8), the switch (13) is the fixed contact a.
When recording audio stereo signals from the input terminals (16) and (17), the fixed contacts are connected to the side.

(24) is a regenerative amplifier to which a regenerative signal is supplied from the fixed contact side of the switch (6);
The signal from 4) is waveform-equalized by an equalizer (25) and made into an easily distinguishable waveform. The output signal of the equalizer (25) is supplied to the data/clock recovery circuit (27),
Here, a clock is extracted from the equalized signal using a PLL or the like to create a pulse corresponding to the bit time, and the recorded digital signal (data) is reproduced by comparing levels at this bit time. Next, a synchronization extraction circuit (not shown) detects a synchronization code to clarify the delimitation of the signal. Since the reproduced digital signal contains jitter, it is demodulated by a channel decoding circuit (27) and then time-base corrected by a time-base correction circuit (28).

In the case of a video signal, this time axis corrected signal is supplied to the time axis expansion circuit (30) through the fixed contact a of the switch (29) and the fixed contact a side of the switch (29'), where the time axis is expanded. After the error correction code decoder (31
), signal processing such as error correction is performed. And even more
The interleaving circuit (32) rearranges the data to restore the digital signal at the time of recording, and this digital signal is converted to an analog signal by the D/A conversion circuit (33), and the original video signal is output to the output terminal (34). I get a signal.

In the case of an audio signal, the time axis corrected signal is supplied to the time axis expansion circuit (35) through the fixed contact a of the switch (29) and the fixed contact side of the switch (29'), where the time axis is expanded. After that, an error correction code decoder (36
), signal processing such as error correction is performed. Then, the data is rearranged in the de-interleaving circuit (37) to restore the digital signal at the time of recording, and if this digital signal is the left channel, it is converted to an analog signal in the D/A conversion circuit (38) and output. The original left channel signal is obtained at the terminal (40), and in the case of the right channel, it is converted to an analog signal by the D/A conversion circuit (39), and the signal is output from the output terminal (41).
) gives the original right channel signal.

Furthermore, the synchronization code included in the output from the data/clock regeneration circuit (26) is separated by the synchronization circuit (42), and based on this, a switching signal for switching data and subcode is formed and supplied to the switch (29). be done. Therefore, the switch (29) is connected to the fixed contact a side when reading data, and is connected to the fixed contact side when reading the subcode. The subcode obtained from the fixed contact side is supplied to the system controller (4), where it is determined whether the tape pattern shown in FIGS. 2 and 3 is a video signal or an audio signal, and the subcodes shown in FIGS. In the case of a tape pattern like the one shown in Figure 6, the channel number is determined and the name is determined. The judgment result in the system controller (4) is supplied to the synchronization circuit (42), and the synchronization circuit (42) switches the switch (29') between fixed contacts a and 6 when the signal is a video signal or an audio signal, and the channel number In this case, the switch (29') is switched between the fixed contact and d. In other words,
If it is a video signal or an audio signal, the synchronization circuit (42)
The video/audio switching signal is from the switch (29'
), and the switch (29') is connected to the output terminal (34).
When a video signal is taken out from the input terminals (40) and (41), it is connected to the fixed contact A side, and when an audio stereo signal is taken out from the input terminals (40) and (41), it is connected to the fixed contact A side.

In addition, when the channel number is selected, a channel switching signal is supplied from the synchronization circuit (42) to the switch (29'),
The switch (29') is connected to the fixed contact d side when the channel to be outputted is being reproduced, and is connected to the fixed contact d side when the channel not to be outputted is being reproduced.

62 circuit operation In such a circuit configuration, one field consists of five trunks, for example, as shown in Fig. 2, of which the video signal V is recorded on four tracks, and the audio signal A is recorded on the remaining one track. The case where such a tape pattern is recorded and played back will be explained. In the recording mode, the switch (6) is connected to the fixed contact a side by a switching signal from the system controller (4). Now, a video signal is supplied from the input terminal (8), and the input terminal (16)
When audio signals are supplied from
, (19) etc., the signal is processed and the switch (13)
appears at fixed contacts a and b.

At this time, the switch (13) is switched according to the time base compression ratio of the time base compression circuits (12) and (22) by a switching signal from the synchronization circuit (23). That is, the switch (13) is switched between fixed contacts a and b at a ratio of 4:1 within the l field period.

The audio signal and video signal that have passed through the switch (13) pass through the fixed contact a of the switch (6), and then are transferred to the switch (3).
It is selectively supplied to rotary heads (2A) and (2B) and recorded on tape (1) as shown in FIG. That is, the rotary heads (2A) and (2B) alternately
Of the five trunks in one field period, the video signal (2) is recorded on the first four trunks, and the audio signal A is recorded on the last one track. Although not shown, a subcode is recorded in each track in addition to the original data, and this subcode includes information such as a program number that can be used to identify whether the recorded data is a video signal or an audio signal. ing.

In the regeneration mode, the switch (6) is switched to the fixed contact side by a switching signal from the system controller (4).

Then, the tape (
The audio and video signals reproduced from the switch (6) pass through the fixed contact C of the switch (6), are processed by the regenerative amplifier (24), etc. as described above, and appear at the movable contact C of the switch (29).

At this time, the switch (29) is connected to the fixed contact A side for data by the switching signal from the synchronous circuit (42), and is connected to the fixed contact A side for subcode, and the data is connected to the fixed contact A side for data. The subcode is supplied to the movable contact C of the system controller (4). The switch (29') is switched according to the rate of time axis expansion of the time axis expansion circuits (30) and (35) by a switching signal from the synchronization circuit (42) based on an instruction from the system controller (4). That is, the switch (29') is switched between fixed contacts a and b at a ratio of 4=1 within one field period.

The video signal that has passed through the fixed contact a side of the switch (29') is subjected to signal processing in the time axis expansion circuit (30), etc., as described above, and is taken out as the original video signal at the output terminal (34). In addition, the audio signal passing through the fixed contact side of the switch (29') is sent to the time axis expansion circuit (35) as described above.
etc., and is output as an original audio stereo signal to output terminals (40) and (41).

Also, as shown in Fig. 3, one frame consists of 10 racks, and a tape pattern is recorded in which the audio signal A is recorded on one track and the video signal V is recorded on the remaining 9 trunks. , when playing back, in recording mode, the switch (13) is set to 9: within one frame period.
It can be switched between fixed contacts a and b at a ratio of 1. Then, one track is recorded alternately by the rotary heads (2A) and (2B), and audio signal A is recorded on the first track of the 10 tracks of one frame period, and video signal is recorded on the remaining nine tracks. V is recorded.

Of course, in this case as well, in addition to the original data, a subcode containing information for identifying whether the data is a video signal or an audio signal is recorded on each track, although not shown.

In the reproduction mode, the switch (29) is connected to the fixed contact a side for data and to the fixed contact side for subcode. Further, the switch (29') is switched between fixed contacts a and b at a ratio of 9:1 within one frame period. Then, the original video signal is taken out to the output terminal (34), and the original audio stereo signal is taken out to the output terminals (40) and (41).

The rest is the same as in the case of recording and reproducing the tape pattern shown in FIG.

In addition, when recording and reproducing a tape pattern in which audio data from the first channel to the fifth channel are repeatedly arranged as shown in FIG. 4, in the recording mode, the synchronization circuit (2
The switch (13) is switched to the fixed contact side by the switching signal 3) and held there. and rotating head (2A)
, (2B) first channels the first channel (Audio
1) is recorded alternately one track at a time, i.e., the data of the first channel is recorded on the first trunk of the first five tracks with the rotary head (2A), and the remaining four tracks are recorded with the rotary head (2A). 2B), (2A)
Next, data of the first channel is recorded on the first track of the second five tracks using the rotary head (2B), and the same process is repeated.

After recording data on the first channel every 5 tracks until the end of the tape, for example, rewind the tape (11) and start recording the data on the second channel (Aud 11) from the top of the tape.
io2) data is recorded every 5 tracks. However, adjacent tracks should have different azimuths.

Therefore, when recording the second channel, the rotary head (2B) records data for the second channel on the first one of the first five tracks, and the remaining four tracks are shared by the rotary heads (2A) and (2B). Without recording, the rotary head (2
Record the data of the second channel in A).

3rd channel (Audio3) ~ 5th channel (^
ud i o5) is also recorded in the same way. However, in this case as well, in addition to the original data, a subcode containing information for identifying the number of channels of data is recorded on each track, although not shown.

In addition, if stable reverse tape running can be achieved,
Even-numbered channels may be recorded in the reverse direction.

In the reproduction mode, the switch (29) is connected to the fixed contact a side for data, and to the fixed contact side for subcode. In addition, the switch (29') is a fixed contact when the channel to be output is being played by a switching signal from the synchronization circuit (42) based on a command from the system controller (4) which receives the subcode and determines the channel number. For example, in Fig. 4, if you want to play only the first channel (Audiol) every 5 tracks, switch (29') ) is connected to the fixed contact side,
When other channels (2nd to 5th channels) are being played, the switch (29') is connected to the fixed contact d side, and when only the 2nd channel (Audio 2) is being played every 5 tracks, the switch (29') is connected to the fixed contact d side. (29') is connected to the fixed contact side, and is connected to the other channels (first channel and third channel).
~5th channel), press the switch (29'
) is connected to the fixed contact d side, and the same applies to other channels below.

In this way, you can select and reproduce only the channels you want to output.

In addition, in FIG. 5, when audio data of each channel is recorded on five tracks as shown in FIG. This is also a tape pattern in which no audio data is recorded. When recording and reproducing such a tape pattern, in the recording mode, the first channel to the g84 channel are recorded in the same manner as in the case of FIG. 4, and the fifth channel is not recorded.

Also, even in the playback mode, the first to fourth channels are recorded in the same way as in the case of Fig. 4, and in the case of the fifth channel, the synchronization circuit (42) cannot detect any synchronization code, so the switch (29) is turned off. It is in an open state in which it is not connected to either fixed contacts a or b.

In this way, only the first to fourth channels can be selected and reproduced.

Figure 6 shows a tape pattern in which a tape (11) is divided into two layers, upper and lower, and multiple channels of audio data are recorded.When recording and playing back such a tape pattern, - set of rotary heads (2A) is used. .

In addition to (2B), there is another set of rotating heads (2A'),
(2B') is used. These rotary heads are arranged on the drum in a relationship as shown in FIG. In other words, FIG. 7 schematically shows the configuration of a five-track device for recording and reproducing tape patterns as shown in FIG. 6.
is a plan view, and FIG. 7B is a front view.

1-turn head (2A) and (2B) are rotating upper drums (50)
The rotary heads (2^') and (2B') are disposed facing each other at an angular interval of 180' around the periphery of the rotary heads (2^') and (2B'), respectively, and are offset from the rotary heads (2A) and (2B) by 90° in the circumferential direction.
Moreover, there is a predetermined step difference in the width direction, for example, about 1/2 of the tape width.
placed at a distance of

In addition, the tape (1) is attached to the upper drum (50) and the lower drum (
51) in a predetermined angular range, for example, about 180°; therefore, as shown in FIG. ^
), (2B), tracks with a predetermined track angle φ are sequentially recorded, and the upper half (upper stage) of tape (1)
Tracks having a predetermined track angle φ' are sequentially recorded by the rotary heads (2A') and (2B'). At this time, the tape running directions are reversed when recording the upper and lower stages.

Also, although not shown in the circuit, there are two sets of rotations (2A).
, (2B) and (2^'), Tape end detection 'a' (not shown) between (2B') and switch (6)
A switch is provided which is switched by a switching signal formed in the system controller (4) based on a tape end signal supplied from the tape end signal.
) head (2A) when recording and playing back.

(2B) is used, and when recording and reproducing on the upper stage of tape (1), the head is switched so that heads (2A') and (2B') are used.

In the recording mode, the first channel is the rotary head (2A
), (2B) are recorded on the lower stage of the tape (1) in the same way as in the case of Fig. 4, and when the tape reaches the end, the tape running direction is reversed, and this time the second channel is recorded by the rotating head (2A'), ( 28') is recorded on the upper row of the tape (1) in the same way as in the case of Fig. 4, and thereafter it is recorded sequentially in the same way.In the end, the odd numbered channels are recorded on the lower row of tape (1), and the even numbered channels are recorded on the upper row of tape (1). It will be recorded.

In playback mode, odd numbered channels are rotating heads (2A)
, (28) reproduces the tape (1) from the lower stage in the same way as in Figure 4, the even channels are played from the rotating head (2A'), and (2B') reproduces the tape (1) from the upper stage as in Figure 4. Reborn as Sono-sama.

In this embodiment, the audio signal is recorded over the entire length on one track, so even if there is a horizontal scratch in the center of the tape, it is possible to correct the missing audio signal. Since the data signal (subcode) serving as information at the time of search is also recorded on one track along with the audio signal, there is no need to record the same data signal for several seconds as in the conventional case.

Moreover, according to this embodiment, the so-called beta old PiJ? 3
It does not have the disadvantage of not being able to do post-recording like the AFM method of the old VH3 Pi, and allows for highly flexible audio recording without the problem of crosstalk between video and audio signals like the 8n++w PCM.

In addition, V
By using the TR as a dedicated audio recording/playback device, a compact and long-lasting audio recorder can be realized.

Furthermore, since we used a recording method in which one heavy metal part of the L field or one frame segment is used exclusively for audio, even if the entrance or exit is poor, the tape is damaged, the edges are damaged, etc., the audio will not be recorded. each channel will be damaged evenly and slightly,
This is also advantageous in terms of error correction.

l] Effects of the Invention As described above, according to the present invention, one field or one frame of video signals is divided into a plurality of trunks and recorded, and audio signals are recorded at predetermined intervals. Even if scratches occur in the longitudinal direction, it is possible to correct missing audio signals, and there is no need to record data signals such as subcodes over a large number of tracks during high-speed searches.

[Brief explanation of the drawing]

FIG. 1 is a circuit configuration diagram showing one embodiment of the present invention, FIGS. 2 to 7 are diagrams for explaining the operation of the present invention, and FIG.
The figure is a diagram for explaining a conventional example. +11 is a magnetic tape, (2A), (2B) is a rotating head, +3), (a), (13), (2
9), (29') is the switch, (4) is the system controller, (91, (18), (19) is A
/D conversion circuit, (10) and (20) are interleaving circuits, (11) and (21) are error correction code encoders, (12) and (22) are time axis compression circuits, and (14) is a channel coding circuit. be.

Claims (1)

[Claims] A digital signal recording device characterized in that a video signal of one field or one frame is divided into a plurality of tracks and recorded, and an audio signal is recorded at predetermined intervals.