JPH02302187A - Moving picture recording and reproducing system - Google Patents

Abstract

PURPOSE:To suppress the production of a recording/reproduction disabled area by recording an input moving picture signal to small split areas resulting from one recording/reproducing area and moving a recording/reproducing head to a succeeding area in the designated order with non-recording/reproducing time length of the input moving picture signal. CONSTITUTION:An optical disk 12 is provided with 1st, 2nd and 3rd recording/ reproducing areas 21, 22, 23 split in a length of 1/3 circumferential length with respect to the circumferential direction, and each recording/reproducing area is split into lots of small split areas radially. Then the track number is set within a range where an optical head 13 is jumped in the non-recording/ reproducing time length. The 1st frame of the input moving picture signal is recorded to a small split area of the recording/reproducing area 21 of the recording medium 12 with a delay of one period and the optical head 13 is sought in a time left by compression. Thus, while the optical head 13 records the data by the 1st frame and seeks the disk afterward, the 2nd frame is recorded in an analog memory 2.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a moving image recording/reproducing method for recording/reproducing moving images on an external recording medium such as an optical disk having concentric or spiral information tracks. It is.

(Prior Art) Various types of moving image recording and reproducing systems using optical discs have been developed.
Specific examples include those described in Publication No. 78639.

Here, as shown in Fig. 5, video signals, audio signals, and data signals encoded in spiral or concentric information tracks are stored on the optical disk, and the optical transmission characteristics, reflection characteristics, phase characteristics, polarization characteristics, etc. It is recorded as optical information (pits) such as characteristics. Information recorded on these optical disks is recorded, for example, by rotating the optical disk 31 on a spindle 32 at a speed of 1800 revolutions per minute, and recording the information on the spiral or concentric information tracks 3 of the optical disk 31.
3, the light emitted from a light source 34 such as a laser,
The reflected light is projected through the lens 35, the half mirror 36, the reflective mirror 37, and the objective lens 38, and is modulated based on the optical information in the information track 33.
The light is reflected by a mirror 36, detected by a light receiving device 40 via a lens 39, and reproduced.

Here, the optical system (34 to 40) is supported by a pickup 41 and is configured to be able to move integrally with respect to the radial direction of the optical disc 31, so as to sequentially scan the information tracks in the radial direction. There is. In addition, the optical disk 31
In order to record information on the optical system, for example, in the optical system shown in FIG. 7, the half mirror 36, lens 39 and light receiving device (2) are removed, and a modulator is placed between the light source 34 and the objective lens 38. A structure is prepared in which the light source 34 emits light with higher energy than that during reproduction, and this light is modulated by the modulator based on the information to be recorded, and the optical disc 31 is emitted from the inner circumference side to the outer circumference side. The information is projected toward the side or from the outer circumference toward the inner circumference, and in the course of the track movement, a spiral or concentric information track is formed by one rotation at a time.

When accessing information for new recording or playback, the ZETSUQUARA 7''41 is moved in the radial direction to an empty track or to the vicinity of the target track (coarse access). Next, the light deflection means (
(not shown) is used to focus a light beam on the corresponding track (precision access).

In such a recording medium, as shown in FIG. 6, a moving image signal for one frame is recorded on one round of a track, and this is continuously written to each track. , the vertical blanking period of the television signal (approximately 1
By jumping forward or backward in the track at a position corresponding to ms), special operations such as forward, fast forward, reverse forward, etc., or continuous recording/reproduction between discontinuous or tracks are performed.

(Problem to be Solved by the Invention) However, the mass of the pickup 31 described above is quite large, and not only does it take time to move (rough access), but also the high track density makes it difficult to Since access is required, the number of tracks that the Big Ara 7'41 can move to in the vertical ranking period, that is, the non-image signal period is small, and there are severe restrictions on continuous playback between discontinuous tracks. be. This point will be specifically explained with reference to FIG. A moving image A on a newly formatted recording medium, for example, an optical disk.

The recording positions of B and C follow the track order.

Next, when moving image B is erased and a shorter moving image than moving image B is recorded from the Nth track,
An empty track remains before the moving image C recording track. Then, after moving image A is further erased, moving image E, which is longer than moving image A, is recorded from the 0th track.
The moving images E are sequentially recorded up to the first track, but there are no empty tracks after that until the 82nd track. Therefore, if the number of tracks on which moving images have been recorded exceeds the non-image signal period, it will not be possible to continue recording in real time following the input of the moving images to be recorded. Generally, the number of tracks used for one moving image file is several hundred or more, which far exceeds the number of tracks that can be played during a non-image signal period. In this way, when erasing one moving image in an area where multiple moving images are continuously recorded and recording another moving image, the length of the moving image to be recorded later There is a restriction that the length of the previous moving image (erased) must be equal to or shorter than the length of the previous video (erased), and the empty track area caused by the difference in the number of tracks between the former and the latter cannot be used for continuous recording/playback. The area becomes unusable. Such an area will continue to increase as recording/erasing is repeated on the recording medium.

To solve this problem, conventional recording and playback methods
By compressing the input moving image signal to be recorded and shortening the recording time, the time until the start of the next recording is increased, and the number of tracks that the optical head can move during this time is increased. However, in this conventional method, due to the above-mentioned time compression, the yield rate of the recording medium is significantly reduced.

(Objective of the Invention) The present invention has been made based on the above circumstances, and it suppresses the occurrence of areas where recording/reproduction is not possible on a recording medium, improves the utilization efficiency of the recording medium, and improves the usage efficiency between discontinuous tracks. ,
The present invention aims to provide a moving image recording/playback method that can realize continuous recording/playback in real time.

(Means for Solving Problem 11) Therefore, in the present invention, in a moving image recording and reproducing method in which moving image information is recorded on a disk-shaped recording medium along concentric or spiral tracks, one or more frames are recorded. The input video signal of the unit video recording/playback period is divided into multiple recording/playback areas in the circumferential direction of the recording medium, and the time length of each recording/playback area is divided into multiple units in the radial direction of each recording/playback area according to the scheduled order. In addition to recording in the subdivided areas divided into
The number of tracks in the sub-divided area is set to a size that allows the recording/playback head to move within the non-recording/playback time length of the input video signal, and the above order is such that one recording/playback area is set within the non-recording/playback time length of the input video signal. The recording/reproducing head is designated to circulate between all the recording/reproducing areas while jumping from one sub-area of the recording/reproducing area to another sub-dividing area of the other recording/reproducing area.

(Function) In this way, after an input video signal is recorded in a subdivided area of one recording/playback area, all the recording/playback areas are circulated during the non-recording/playback time length of the input video signal. Since the recording/playback head is moved to the next subdivision area of the recording/playback area in the order specified by The occurrence of unreproducible areas can be suppressed, and continuous recording/reproduction can be realized between discontinuous tracks.

(Example) Hereinafter, an example of the present invention will be specifically described with reference to the oral surface. Here, an optical disk 12 is used as an external recording medium having concentric or spiral information tracks, and first, second, . A third recording/reproducing area 21, 22, and 23 is provided. Further, each recording/reproducing area is divided into a large number of sub-areas (in this embodiment, three sub-areas) in the radial direction. Each of these subdivision areas is
21a, 21b, 21c, 22m, 22b, 22c and 23&.

23b and 23e, and the number of tracks therein is set within a size range that allows the optical head (recording/playback head) 13 of the moving image recording/playback means to jump within the non-recording/playback time length. ing. The optical head 13 is provided with a slider IIK and scans the recording/reproducing area in the radial direction.

Since the slider 11 is driven by the slider motor 10, the slider motor 10 is controlled by commands from the controller 8. The optical disc 12 is driven by a motor 14, and is set to a stirrup cycle of one frame of a moving image, for example, 1200 revolutions per minute.

The input video signal to be recorded is sampled at an arbitrary clock frequency in analog memory °2 °3, and
It is written as an analog signal consisting of OD. Then, this signal is given to the optical head 12 as a recording signal by the encoder 4, and is projected onto the optical disk 12 as an optical signal and recorded. Further, when the light projected from the optical head 13 is reflected from the optical disk 12, a reproduction signal is extracted from the reflected light by the decoder 5, and is outputted as an output moving image signal of the original frequency in the analog memory 6.7.

Next, moving image recording will be explained. When the recording instruction signal 15 is input to the controller 8, the controller 8
refers to the management table 9, searches for an empty track number in the sub-divided area of the recording/playback area 21 to record the first frame of the moving image, and controls the slider motor 10 based on that number.
A head movement signal is sent to the optical head to move the optical head to the track for recording the first frame. On the other hand, input video signal C, clock frequency! sampled and recorded in analog memory 2. When all the signals of the first frame are recorded in the analog memory 2, the signals in the analog memory 2 are frame transferred to the analog memory 3. The signal transferred to the analog memory 3 is then read out at a clock frequency of 2f, and the time axis is compressed to 1/2. Next, the encoder 4 performs frequency modulation and A pulse modulation, and then the optical head 13 records the signal on the optical disk 12.

At this time, the rotation period of the optical disk 12 is V of the frame period.
3, the time-axis compressed recording signal is stored in the recording/playback area 2.
1 sub-division area, that is, 1/3 of the optical disc 12
It is recorded as a moving image recording signal for one frame on the circumference. Also, after the optical head 13 records the compressed signal of the first frame, the remaining non-recording time length (optical disc 1
2 1/3 rotation), the controller 8 searches the management table 9 and searches for an empty track number in which the second frame is to be recorded from among the sub-divided areas of the recording/playback area 22 in the scheduled order. , the optical head 13 is accessed there. In other words, the input moving image signal is delayed by one cycle, and the first frame is recorded in the subdivided area of the recording/reproducing area 21 of the recording medium 12, and the optical head 13 is used for seeking in the dead time left by compression. .

Therefore, while the optical head 13 records the first frame and then seeks, the analog memory 2 records the second frame.

FIG. 2 shows the operation of each signal processing section at each time during recording. In this way, the input moving image signal is recorded in the recording/reproducing area 21, 22 or 23.

In which recording/playback area 21, 22, 23 is the input video image recorded?
The controller 8 specifies whether to record in the subdivided area using the management table.

Next, reproduction of moving images will be explained. When the playback instruction signal 16 is input to the controller 8, the controller 8 refers to the management table 9 and selects a small area of the recording/playback area 21 (or 23) where the first frame of the moving image to be played is recorded. The track number of the divided area is determined, a head movement signal is sent to the slider motor 10, and the optical head 13 is made to access the target track. When reading starts, the output moving image signal is demodulated by the decoder 5, sampled at a clock frequency of 2f, and written into the analog memory 6. The time length required for reading is half a period, and during the next half period, the optical head 13 is made to access the recorded track number of the second frame, which the controller 8 searches based on the management table 9. As soon as the reading of the first frame is completed, the contents of the analog memory 6 are transferred to the analog memory 7, and the analog memory 7 doubles the time axis by reading at the clock frequency f, and restores the original moving image. Outputs the playback signal as a signal. FIG. 3 shows the operation of each part at each time during this reproduction.

In the above embodiment, each recording/reproducing area 21°, 22.
The 23 sub-division areas are divided into three, and the recording/playback order is set as shown in Figure 4 (&) in management table 9, but generally when the area is divided into four , in the radial direction one by one, for example, in the set order as shown in FIG. 4(b), and is set to jump within one unrecorded playback time length. In this case, the length of time that the optical head 13 traverses each sub-division area is within each non-recording/reproducing time length.

The optical head 13 can cycle through the tracks of all the recording/reproducing areas based on the management table.

In addition, in this embodiment, only one recording/reproducing means is prepared, and the recording signal is time-compressed to one half, and the time length left by the compression is used as the non-recording/reproducing time length, and the optical Although it was used for jumping the head 13, a plurality of recording/reproducing means were prepared corresponding to one optical disk 12,
For example, in a method in which two optical heads are used alternately, when one optical head is recording/reproducing a small divided area of one recording/reproducing means, the other optical head is used next for recording/reproducing. the controller 8 so as to access the tracks of the subdivision area of the other recording/playback area to be played back;
Control may be performed based on management table 9. In this case, it is not necessary to compress and record the unit input moving image signal and expand and reproduce the output moving image signal as in the above embodiment.

(Effects of the Invention) As described in detail above, the present invention can convert input moving image signals into one
After recording in the sub-divided areas of one recording/playback area, the next recording/playback area is recorded in the specified order so as to cycle through all the recording/playback areas according to the non-recording/playback time length of the input video signal. Since the recording/playback head is moved to the subdivided area, it is possible to suppress the occurrence of unrecordable/playable areas on the recording medium without reducing the utilization rate of the recording/playback area. Discontinuity allows continuous recording/reproduction between tracks.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, FIGS. 2 and 3 are time charts showing the operating status of each signal processing section during recording and playback, and FIG. 4 is a controller management table. 5 is a diagram showing the configuration of a conventional optical system, and FIG. 6 is a schematic diagram showing the division of regions on an optical disc. FIG. 7 is a schematic diagram showing how tracks are used for conventional recording/erasing.

Claims (1)

[Claims] In a video recording and reproducing method in which video information is recorded on a disc-shaped recording medium along concentric or spiral tracks, an input video signal with a video recording/playback cycle of one or more frames is recorded. , recording is performed in the sub-divisions divided in the radial direction of each recording/playback area in accordance with the scheduled order at each passing time length of the recording/playback area divided in the circumferential direction of the recording medium, and the above-mentioned sub-division The number of tracks in the area is set to a size that allows the recording/playback head to move within the non-recording/playback time length of the input video signal, and the above order is a subdivision of one recording/playback area within the non-recording/playback time length. A moving image recording/playback method characterized in that the moving image recording/playback method is specified to circulate between all recording/playback areas while jumping from one area to a subdivided area of another recording/playback area.