JPH05182122A - Magnetic recording/reproducing device - Google Patents

Abstract

PURPOSE:To eliminate the influence of a track shift on the other channels at the time of insertion by recording the audio data of the same channels along the longitudinal direction of a magnetic tape. CONSTITUTION:The audio data of plural channels are recorded by using recording heads Ha to Hd for recording video data. The audio data are spread to the track Ty of the oblique direction of a magnetic tape 3 every channels and recorded and the audio data of the same channels are recorded along the longitudinal direction Tx of the magnetic tape 3. That is, the audio data of each channel are distributed and recorded in segment unit in parallel along the longitudinal direction Tx of magnetic tape 3. That is, the audio data are recorded every channel making phases in the track direction. Thus, even when a tracking error exists at the time of individual editing, its influence on the other channels is eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus suitable for application to a D2 type digital VTR or the like in which audio data of a plurality of channels are distributed and recorded by a plurality of recording heads.

[0002]

2. Description of the Related Art A D2 type digital VTR for recording / reproducing a composite video signal is known. When recording a plurality of audio data converted into PCM by this digital VTR, a tape format (tape pattern) as shown in FIG. 7 is obtained.

In the figure, a guard band is shown to exist between tracks, but in actuality, high density recording is performed in a guard bandless state and with different azimuths between tracks.

In the figure, 3 is a magnetic tape, and the number of recording channels is 4. Digital video data is segment-recorded in the central portion of the magnetic tape 3. In this example, four recording heads arranged on the rotary drum 2 of the rotary magnetic head 1 shown in FIG.
Recording heads Ha to Hd arranged with an interval of 0 °)
Is used to simultaneously record one segment and two tracks. One field requires 3 segments and is recorded.

Both sides of the video data recording area (both ends of the magnetic tape 3) are used as PCM audio data recording areas. PCM audio data is recorded using a recording head that records video data. That is, 4-channel audio data is distributed and recorded over two tracks simultaneously recorded by using the above-described four recording heads Ha to Hd.

[0006] Here, in recording audio data and the like, factors that deteriorate the error rate are generally head clogs, longitudinal slashes (scratches), scratches, and data dropout due to dust adhesion. .. Therefore, in the current D2 format, as shown in FIG. 7, the audio data is distributed and recorded on the four recording heads as described above, and double recording is performed at both ends of the track to further reduce errors (duplicated recording of the same audio data. ) Is done.

In the figure, Aij represents a sector of the audio track recorded in a distributed manner, i is a recording channel number, and j is a sector number. The first recording (first copy) is recorded in the latter half (upper end side) of one track, and the second copy of the same audio data is recorded in the first half (lower end side) of the next segment.

[0008]

As described above, the current D2 is used.
In the format, the distributed recording as described above is performed in order to improve the error rate of the audio data. However, if this distributed recording is performed, it is inconvenient in the case where the audio channel is independently edited as described below. Dots occur.

That is, when the just-on-track cannot be performed due to the mesa accuracy of the recording heads Ha to Hd and the accuracy of the servo, if the independent edit is performed, the adjacent track data is overwritten or the self-editing is performed as shown in FIG. Erasing remains on the truck. In this case, since the audio data of different channels are recorded especially in the adjacent tracks of the audio data, the channel to be erased (eg A10) when it is not the just on track.
As shown in Fig. 9, some audio data is left unerased, so it is not necessary to erase it from adjacent channels (hence A31).
Some of the audio data will be erased.

The unerased data becomes in-phase azimuth, which is a major factor in deteriorating the error rate. The erase residual can be improved by using an erase head wider than the recording head as shown in the figure, but since the erase head scans across adjacent channels, the erase of adjacent tracks becomes a problem this time.

A VTR (for example,
Long time recorder (D2-LP) that doubles recording time
In such cases, since the track pitch is about 1/2 of the current one, it is considered that the influence of mesa accuracy will be further increased.

Therefore, as one solution, a method of reading the data of the adjacent track by using the pre-read head and re-recording is conceivable. However, the reliability is lowered in that the original data is rewritten, and the number of reproducing system circuits is increased.

From the above, the problems when the track shift occurs at the time of editing with the current D2 format are summarized as follows. When editing, erasure of the same azimuth and overerasure of adjacent track data occur, and a pre-read head is required for improvement. In the pre-read method, reliability is lowered in that the original data is re-recorded. In the pre-read method, the number of reproduction system circuits will increase.

Therefore, the present invention has solved such a conventional problem, and a magnetic recording / reproducing apparatus capable of realizing editing of a single channel even when a track shift occurs without affecting other channels. Is proposed.

[0015]

In order to solve the above-mentioned problems, the present invention has a plurality of recording heads for recording audio data of a plurality of channels, and these recording heads cause the audio data to be oblique to a magnetic tape. It is characterized in that the audio data of the same channel is recorded along the longitudinal direction of the magnetic tape while being distributedly recorded for each channel on the tracks of the direction.

[0016]

The audio data of a plurality of channels is recorded by using the recording heads Ha to Hd of FIG. 8 for recording video data. As shown in FIG. 2, the recording heads Ha to Hd dispersely record the audio data on the tracks Ty in the oblique direction of the magnetic tape 3 for each channel, and the audio data of the same channel are distributed along the longitudinal direction Tx of the magnetic tape 3. Will be recorded.

That is, along the longitudinal direction Tx of the magnetic tape 3, the audio data of each channel is distributed and recorded in segment units in parallel therewith. For example, in the case of 4-channel recording, 4-channel audio data is sequentially recorded on the upper end side of the video data recording area toward the end of the magnetic tape 3.

When video data is simultaneously recorded on two tracks of one segment, an audio data block Bi (i = a, b, ...・ ・) Audio data in) is recorded at the same time.

Audio data is recorded in duplicate on both sides of the video data. Of course, the audio data may be recorded only on the first copy side.

1 along the longitudinal direction of the magnetic tape 3
Audio data for channels is recorded, and this is recorded for each channel with a phase in the track direction. Therefore, even if there is a tracking error during independent editing, it does not affect other channels.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a case where an example of a magnetic recording / reproducing apparatus according to the present invention is applied to a D2 format digital VTR will be described in detail with reference to the drawings.

FIG. 1 shows a concrete example of the PCM audio data recording / reproducing section 10 of the digital VTR. In the figure, channel 1 to channel 4 are connected to input terminals 11 to 14.
Up to the analog audio signals SA1 to SA4 are supplied to the A / D converters 15 to 18, for example, PCM.
Is converted into digital audio data. The PCM audio data is supplied to the sector data forming circuits 20 to 23, and data is formed for each sector required for distributed recording.

The sector data is directly supplied to the selector 30 and also to the memories 41 to 44, and is stored for use for the second copy. The sector data output from the memory is also supplied to the selector 30. The selector 30 has a selection signal C corresponding to the first copy or the second copy.
C is supplied. The selected sector data is further supplied to the selector 50 at the next stage and distributed to each channel. The channel selection signal SC is supplied to the selector 50 for distribution for each channel.

The audio data distributed to each channel is supplied to a delay circuit 60 for adjusting the recording timing, delayed by a predetermined time, and then the corresponding recording heads Ha to.
Recorded by Hd.

When audio data is recorded for each channel, the present invention controls the tape format as shown in FIG.

The characteristic of this tape format is that audio data of the same channel are arranged along the longitudinal direction of the magnetic tape 3. In other words, distributed recording is performed for each channel in the oblique track direction Ty. That is,
One row of sectors for channel 1 is recorded in the longitudinal direction Tx,
A sector for channel 2 is recorded in the sector area in the next track direction, a sector for channel 3 is recorded in the sector area in the next track direction, and a sector for channel 4 is finally recorded. ..

When the recording channel is determined for each phase in this way, sectors of the same channel are always arranged at the same position in the track direction Ty of the magnetic tape 3.

Then, audio data of the same sector (same audio data) is recorded under the video tracks of different segments in an overlapping manner.

Since the video data is simultaneously recorded on one segment and two tracks, the audio data blocks Ba, Bb, ..., Which are recorded over two tracks, are used because of the use of the recording heads Ha to Hd which are also used for the video data.・
・ The audio data inside is also recorded on two tracks at the same time.

As described above, since the audio data for 4 channels is recorded in the same segment in an overlapping manner, the number of sectors per segment (2 tracks) is 16 sectors, which is double the current 8 sectors (see FIG. 8). .. The number of synchronization signals per sector is halved from 6 to 3.

At the time of overlapping recording, the second audio data is recorded in the upper and lower sectors within the segment as shown in the figure, that is, in the case of FIG. 2, the tracks for recording the audio data are different between the blocks Ba and Bb. There is. This reduces data loss at the in point (recording start point) and out point (recording end point) during editing.

The editing operation when the above tape format is used will be described below. Figure 3 shows channel 1
Only the sectors A10, A11, A12, A13 of
The diagonal direction is the azimuth direction.

Since only the sectors of the same channel 1 are lined up in the longitudinal direction of the magnetic tape 3 as described above, when there is a track deviation during editing as shown in the figure, new track data of the same channel 1 remains as the track deviation. It will be recorded as audio data. for that reason,
Even if there is a track shift, the audio data can be rewritten without affecting the data of other channels. Further, since the audio data of the same channel is recorded on both upper and lower ends of the video track in an overlapping manner, it is less likely to be affected by a scratch, a scratch, dust or the like in the longitudinal direction of the magnetic tape 3.

By the way, in the case of the tape format shown in FIG. 2, the position of the duplicate recording of the audio data has the same form as in the current D2 format, and the upper data of the previous segment is the lower data of the next segment. ..
Then, since the processing is performed in segment units, the shuffling circuit can be small in scale when performing field shuffling processing, for example, as a method for reducing the occurrence of errors in reproduced data.

The track formation state of FIG. 2 is shown in detail in FIG. 4, and recording is performed so that the IN points of the same segment are aligned. In this way, two different azimuths can be erased at once using a two-track wide erase head.

Since the present invention does not relate to the number of segments constituting one field, even if the one-field three-segment system adopted in the NTSC system as in the above example, one-field four-segments like the PAL system is used. Even if there is, it is possible to take the same sector arrangement of audio data.

FIG. 5 is a modification of FIG. In this example, the recording positions of the audio data from channel 1 to channel 4 are opposite to those in FIG.

The example of FIG. 6 shows still another example. In this example, the same audio data can be recorded in duplicate in the same segment. 5 and 6
In any case, the same operation as described above is performed, and therefore detailed description thereof will be omitted.

[0039]

As described above, in the magnetic recording / reproducing apparatus according to the present invention, the audio data is recorded along the longitudinal direction of the magnetic tape.

According to this, since the sectors of the same channel are arranged in the longitudinal direction, the track deviation at the time of insertion is strong and there is no influence on other channels. Since it has been recorded twice, it is strong against scratches, scratches, dust, etc. on the magnetic tape. Further, it has a feature that two azimuth data can be erased at once by an erasing head having a two-track width by aligning the recording start points.

[Brief description of drawings]

FIG. 1 is a system diagram showing an example of a recording / reproducing unit for audio data in a magnetic recording / reproducing apparatus according to the present invention.

FIG. 2 is a diagram showing an example of a tape format of audio data.

FIG. 3 is a diagram showing a relationship between a sector and a track shift.

FIG. 4 is an explanatory diagram of a recording start point.

FIG. 5 is a diagram showing another example of a tape format of audio data.

FIG. 6 is a diagram showing another example of a tape format of audio data.

FIG. 7 is a diagram of a tape format in the D2 format.

FIG. 8 is a configuration diagram of a rotary magnetic head used for a D2 type.

FIG. 9 is a diagram showing a relationship between sectors and track deviations.

[Explanation of symbols]

 3 Magnetic tape Aij Audio data sector CH Audio channel

Claims (3)

[Claims] 1. A plurality of recording heads for recording audio data of a plurality of channels, wherein the recording heads dispersely record the audio data on tracks in a diagonal direction of a magnetic tape for each channel, and audio of the same channel is recorded. A magnetic recording / reproducing apparatus characterized in that data is recorded along a longitudinal direction of a magnetic tape. 2. The magnetic recording / reproducing according to claim 1, wherein the audio data of each channel is recorded on an end portion side of the magnetic tape, and the video data is recorded on a central portion thereof. apparatus. 3. The magnetic recording / reproducing apparatus according to claim 1, wherein the same audio data is recorded in duplicate on both ends of the magnetic tape.