JPH0528725A - Magnetic recording and reproduction method - Google Patents

Abstract

PURPOSE:To provide a magnetic recording and reproduction method by which auxiliary information constituted of the plural items of an information signal can be edited at each item. CONSTITUTION:The information signal and the auxiliary information of the information signal are respectively divided and recorded in the areas 3 and 4 of tracks 2a-2h prepared in an oblique direction on a tape 1. Moreover, the auxiliary information is divided into plural information units including at least one item, and selectively recorded in the different tracks at each information unit. The auxiliary information constituted of the plural information units of the information signal is recorded in different tracks at each information unit, so that the auxiliary information can be edited at each information unit. Thus, the magnetic recording and reproducing device equipped with a high speed editing function can be realized.

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 method for recording / reproducing images, sounds, data, etc. on a tape.

[0002]

2. Description of the Related Art A magnetic recording / reproducing apparatus using a magnetic tape as a medium such as a video tape recorder (hereinafter abbreviated as VTR) has been put into practical use and prevailing. In addition, downsizing of devices by further high density recording and development of digitization are being carried out by each company. When recording an information signal, record the time code indicating the absolute address on the tape, the user time code determined by the user, and additional information such as a title indicating the content of the information. It is recorded in a specific area. The track pattern is shown in FIG. 41 is a magnetic tape, 42a to 42d are tracks, 43 is an information signal area, and 44 is an auxiliary information area. The incidental information of the information signal manages the recorded information,
Very useful for editing. Here, the supplementary information includes information on a plurality of items as described above, and these items of information cannot be separated for each item.

[0003]

However, if a plurality of items are included in the supplementary information recorded on one track as described above, only one of the items should be newly rewritten. I can't.

An object of the present invention is to provide a magnetic recording / reproducing method capable of editing incidental information of an information signal consisting of a plurality of items for each item.

[0005]

In order to solve the above-mentioned problems, the magnetic recording / reproducing method of the present invention is such that the information signal and the incidental information of the information signal are divided into respective regions on the same slanted track on the tape. The additional information is divided into a plurality of information items including at least one information unit, and the tracks are selectively recorded for each of the information items with different tracks.

[0006]

According to the present invention, incidental information consisting of a plurality of information items is recorded on a separate track for each item,
Editing can be performed for each information item of the incidental information.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic recording / reproducing method according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a track configuration diagram on a tape of a magnetic recording / reproducing method according to an embodiment of the present invention.
In FIG. 1, 1 is a magnetic tape, 2a to 2h are tracks, 3 is an information signal area, 3a is an audio signal area, 3b is a video signal area, and areas 4a to 4h are auxiliary information areas. Further, 5 is an area usually called a preamble, and the positioning signal 6 is recorded in a part or all of the preamble of one track. In addition, a pilot signal for tracking is sequentially frequency-multiplexed in the preamble 5.

When only the supplementary information is rewritten on the recorded tape, tracking can be performed at the time of editing by the signal of the preamble 5 even if the conventional ATF method is used. In addition, the positioning signal 6 makes it possible to obtain accurate edit timing for starting and ending recording in the auxiliary information areas 4a to 4h. Although details are omitted here, it is possible to rewrite only a partial area of one track using a conventional method.

Here, if additional information consisting of a plurality of information items including at least one information unit is recorded in the additional information area of a different track for each information item,
It is possible to rewrite only the desired information item of the supplementary information. Although FIG. 1 shows the case where an information signal is recorded and reproduced in frame units with 8 tracks as one frame, a search for a track in which a desired information item is recorded is performed, for example, within one frame. This can be easily performed by defining the track number and the information item to be recorded in the additional information area of the track.

According to this embodiment, the supplementary information of the information signal can be edited for each item, so that the editing function of the VTR can be enhanced.

Here, consider a case where both the information signal and the incidental information are digitally recorded. In the case of digital recording, data is usually grouped into sectors, a sync signal is given to clarify the delimiters of data at the time of reproduction, and processing such as error correction is performed for each sector. That is, during reproduction, reproduction is performed in sector units. In this example, for example, the video / audio information is 100 bytes / sector, and the supplementary information is 10 bytes / sector. From the viewpoint of data redundancy, it is desirable that the sector length is long, but the sector information should be shortened so that the supplementary information can be read even if the reproducible period across tracks is shortened as in high-speed search. You can increase the reading probability by choosing.

Further, among a plurality of information items of the incidental information,
If at least one of them is a time code indicating an absolute address on the tape, it is very effective when performing a search operation with continuous information signals. That is, when the correspondence between the time code and the contents of the information signal is known, the information signal to be searched can be accessed at high speed.
This is because the time code is a numerical value that increases or decreases at a constant rate for each frame, so even if you make a reading error, you can easily correct it from the time code before and after that point, so you can write the tape at high speed. It is relatively easy to read the time code even when driving. In other words, by searching the time code,
The information signal to be searched can be accessed at high speed. Further, in order to realize this function, it is preferable that only the time code can be rewritten from the plurality of information items of the additional information in order to ensure the continuity of the time code over the entire area of the tape. In this embodiment, since the time code is recorded as a single information item on a different track from other information items, the other information items are not erased when the time code is rewritten.

Further, a case where at least one of a plurality of information items of the supplementary information is used as a cue signal will be described. In this case, if the cue signal is recorded in the incidental information area of the recording start track of the information signal which should be distinguished from the others, it is effective in searching the recording start position of the information signal. This cueing signal may be detected more easily than the time code, because, for example, a signal of a specific single frequency may be recorded. In other words, by searching for the cueing signal, the access to the recording start position can be performed at a higher speed than searching by the time code. Further, in order to expand the use of this function, it is preferable that the cue signal can be attached to any recording position of the recorded tape and can be deleted. Only the cue signal should be rewritable. In this embodiment, since the cue signal is recorded as a single information item on a different track from other information items,
Other information items are not erased when rewriting the cue signal.

FIG. 2 is a track configuration diagram on the tape in the embodiment in consideration of the thinning of adjacent tracks due to overwriting when rewriting with a magnetic head wider than the track pitch. . In this embodiment, information items having different additional information are recorded in the additional information areas 24a to 24d for each of a plurality of continuous tracks (every two in FIG. 2). The additional information areas 24a to 24d respectively indicate areas of a plurality of tracks, which means that information items having the same content are recorded. The other areas are the same as those in the above-described embodiment and will not be described.

If different information items are recorded for each of a plurality of tracks in this way, when one information item is rewritten, the degree of thinning of adjacent tracks due to overwriting by a wide head can be greatly reduced. . FIG. 3 shows how only one track is rewritten among the continuous tracks. In FIG. 3, 1 is a magnetic tape, 32a to 32c are tracks, 32d is a rewritten track, and 37 is a magnetic head. It can be seen that if only a certain track is rewritten by the wide head, both adjacent tracks will be thinned by overwriting. Here, different information items are recorded for each track, and are recorded on both adjacent tracks of a certain track.
If two information items are rewritten, the sandwiched track will be overwritten on both sides, resulting in a significant loss of weight. However, if different information items are recorded for each of a plurality of tracks, neither side of the track on which a certain information item is recorded is overwritten, that is, only one side is overwritten, The rewriting of the information item reduces the degree of thinning of the adjacent track.

Further, in this embodiment, since the same information item is recorded on a plurality of continuous tracks, the same information can be read a plurality of times, and the probability of a reading error can be reduced. . In addition, if the information item is a signal of a relatively low frequency that is not easily affected by azimuth loss, and if the recording is such that the position on the track with the adjacent track is corrected, then in the off-track state. However, the signals are detected from the two tracks traced by the magnetic head, and the possibility of reading errors is extremely small. If the track pitch becomes narrow due to the high-density magnetic recording, there is a high possibility that the track will be off-track due to the influence of disturbance or the like. Become. Further, since the information items having different contents are recorded in the incidental information areas of different tracks, the effect that only desired information items can be edited is retained.

Needless to say, the present invention is not limited to the tracking method as in the above embodiments. As described in this embodiment, the AT by the pilot signal
The F system may be used, or a control signal recorded in a dedicated area like a VHS standard VTR may be used. Further, the method of inserting the positioning signal is not limited to that in this embodiment, and the coincidence of the digital patterns may be detected. Furthermore, in this embodiment,
Although the case of recording / reproducing with the magnetic head of only 1ch is shown, the same effect can be obtained even if the recording / reproducing of 2ch is performed almost simultaneously.

[0019]

According to the magnetic recording / reproducing method of the present invention, the incidental information of the information signal can be individually edited for each item. If the magnetic recording / reproducing method of the present invention is used, It is possible to realize a magnetic recording / reproducing apparatus such as a VTR having a very advanced editing function.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a track according to an embodiment of the present invention.

FIG. 2 is a track configuration diagram in another embodiment of the present invention.

FIG. 3 is a diagram showing how adjacent tracks become thin due to overwriting when rewriting a certain track.

FIG. 4 is a track configuration diagram of a conventional system.

[Explanation of symbols]

1 magnetic tape 2a-2h trucks 3 Information signal area 3a Audio signal area 3b Video signal area 4a to 4h Additional information area 5 preamble 6 Positioning signal

Claims (5)

[Claims] 1. An information signal and ancillary information of the information signal are divided into areas on the same oblique track respectively, and the ancillary information is further divided into a plurality of information items including at least one information unit. A magnetic recording / reproducing method, characterized in that the information is selectively recorded on different tracks for each information item. 2. The magnetic recording / reproducing method according to claim 1, wherein at least one of the plurality of information items is a time code indicating an absolute address on the tape. 3. The magnetic recording / reproducing method according to claim 1, wherein at least one of the plurality of information items includes a cue signal indicating a recording start position of the continuously recorded information signal. 4. The magnetic recording / reproducing method according to claim 1, wherein the plurality of information items are recorded for each of a plurality of continuous tracks. 5. The information signal and the supplementary information of the information signal are divided into areas on the same slanted track on the tape, and the supplementary information and the information signal are provided with a synchronization signal for each sector. The magnetic recording / reproducing method is characterized in that the sector length of is shorter than the sector length of the information signal.