JP2002232848A - Recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize complication and satisfactory high speed reproduction by a narrow track format. SOLUTION: A first recording processing means converts compressed video data into first modulated data. A macro block means 41 makes compressed position data into a macro block and a compressed data conversion means 42 converts compressed video data which are made into the macro block, into search data. A second recording processing means converts search data into second modulated data. A selection means selects compressed video data at the time of recording data in (n-2)-pieces of tracks in the center of n (natural number of N>=)-pieces of tracks on a magnetic tape 48 and selects search data at the time of recording data in the two end tracks. Selected data are recorded in the magnetic tape 48 by a recording head 47 through a recording amplifier 46.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field relating to recording and reproduction of video, and particularly to a helical scan VTR.
The present invention relates to a recording / reproducing apparatus for recording / reproducing when recording / reproducing.

[0002]

2. Description of the Related Art Hitherto, as a device for recording and reproducing video information, a so-called helical scan VTR, which mounts a magnetic head on a rotating drum and scans the head obliquely with respect to a tape to record, has been the mainstay.

[0003] Since a video signal to be recorded is transmitted in a signal format having a certain periodicity, a device for recording and reproducing the video signal also employs a mechanical recording mechanism synchronized with the video signal. Specifically, a video signal transmitted by the NTSC system transmits an image of 30 frames per second,
A VTR for recording the image is a segment recording for recording the image of one frame every one rotation by rotating the rotary cylinder 30 times per second, or dividing and recording the frame at an integral multiple of the number of rotations (for example, 150 rotations). The formula has been taken.
The former is a VHS recording method, and the latter is a digital video DV recording method.

[0004] In addition, tape patterns have been recorded in a tape pattern that consumes the least amount of tape while taking into consideration the convenience after recording and reproduction (easiness of editing and recording or cutting and editing again on a recorded tape).

Further, in order to enable editing after recording, for example, when interviewing a camera, mechanical accuracy and tape must be adjusted so that compatibility between the recording device and the device to be edited thereafter can be ensured. The tape format is determined in consideration of the deformation of the tape. In general, in order to enable compatible reproduction, the track width (off-track margin) that determines the position of the reproduction head on the track during reproduction should be twice as large as the track width required for reproduction. It is a guide on the tape format.

[0006]

A recording / reproducing apparatus is required to be able to record in a longer recording time than when recording in a conventional tape format. In the background, in order to pursue high image quality even in video signals, for example, when recording high-definition HD signals instead of normal NTSC signals, even when recording compressed video data, tape The amount of consumption has increased, leading to a total increase in coverage costs. Therefore, narrowing the track pitch saves tape consumption, enables long-time recording, and is effective in reducing coverage costs. There are two issues in reducing the track pitch.

[0007] The first problem is editing. Even a long-time recording apparatus that records on a narrow track needs to have an editing function, and must be capable of cutting and editing several scenes and connecting. However, if different scenes are connected by another VTR after a scene that has been continuously recorded, there is a possibility that the tracks overlap and the last track of the previous scene is erased, as shown in FIG. In FIG. 18, B36 to B40 are the data tracks of the previous frame, and A1 to A5 are the tracks connected and recorded later. This shows a case where the track A1 overlaps the track B40 due to the error, and most of the track B40 is erased.

When the last one track in one frame is erased, the last frame loses the video signal for one track out of the forty tracks, making error correction impossible.
Practically, a function of complementing with the image of the previous frame of the last screen on the screen is provided to cope with the failure, but there is a disadvantage that the reproduced image becomes a discontinuous picture. If this connection is repeated several times in a short range, the image becomes a jerky pattern containing a correction screen for each edit point, which is not practical for broadcasting.

The second problem is error tolerance. The narrower the track pitch, the lower the S / N ratio of the reproduced signal.
As a measure for improving the S / N ratio deterioration, enhancement of the error correction capability can be considered. There are two major measures to enhance the error correction capability. The first method is to increase the amount of error correction code for recording data. For example, 7
The error correction capability is enhanced by adding the 16-word error correction code to the 77-word data, rather than adding the 8-word error correction code to the 7-word data. However, this technique causes an increase in data, and as a result, there is a problem that the recording wavelength must be shortened in order to perform recording on the same track.

The second method is a method in which the ratio of the data and the error correction code is the same, and the code word is made large. Specifically, the error correction capability is greater when a 16-word error correction code is added to 154-word data than when an 8-word error correction code is added to 77-word data. However, in this method, a code word becomes large, and a sync block for recording by adding ID data and SYNC (Synchronous) data indicating information related to video information to the code word becomes large, and reproduction is performed as in high-speed reproduction of a VTR. When the head plays back over many tracks, the amount of data that can be acquired per track is reduced, so that there is a problem that the speed at which a reproduced image can be confirmed at high speed playback cannot be increased.

The present invention relates to the above-mentioned 2 in narrow track recording.
Solves the problems of editing and high-speed playback, and when editing a tape recorded with a narrow track, there is no problem in the reproduced image even if the track disappears, and it is recorded in a tape format that allows relatively high high-speed playback speed An object of the present invention is to provide a recording and reproducing device.

It is another object of the present invention to provide a recording / reproducing apparatus for improving high-speed reproduction quality in a narrow track format.

[0013]

SUMMARY OF THE INVENTION In order to solve this problem, according to the present invention, a compressed image is recorded on (n-2) central tracks of n tracks (an integer of n.gtoreq.3) on a magnetic tape. Data is arranged, and search data in which a low-frequency component of a compressed macroblock in which a predetermined number of compressed blocks adjacent to each other on a screen are collected on two end tracks is reduced to a predetermined amount or less is recorded and recorded.

The data length to be recorded on the two tracks at both ends is shorter than the data length to be recorded on the (n-2) central tracks.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first aspect of the present invention is a compressed image constituted by a compressed block obtained by dividing a video signal per unit time into a plurality of pixel blocks and performing a compression process on each pixel block. Transfer the data to n
In the number of tracks (n ≧ 3), the center (n−
2) A recording / reproducing apparatus for arranging search data generated from the compressed video data on two tracks at both ends and recording the search data on the two tracks, wherein the search data is adjacent to the compressed block on a screen. Is a data in which the low-frequency component of a compressed macroblock in which a plurality of
A predetermined number or less of the search data is arranged in the two tracks at both ends, and the data length to be recorded for each of the two tracks at both ends is recorded for each of the (n-2) central tracks. This is a recording / reproducing apparatus characterized by being shorter than the data length. In the narrow track format, search data is arranged in a sync block having a short sync block length for high-speed reproduction and recorded on two end tracks. The effect of the thin track at the time of editing is only the search data arranged on the two tracks at both ends, and the editing in the narrow track format becomes possible. Also, in high-speed reproduction, data that can cover a screen per unit time with a short data length is arranged as search data in two tracks, so that the image update rate during high-speed reproduction does not decrease.

According to a second aspect of the present invention, a video signal per unit time is divided into a plurality of pixel blocks, and compressed video data constituted by a compression block subjected to a compression process for each of the pixel blocks is converted to magnetic data. N pieces on the tape (n ≧
A recording / reproducing apparatus which arranges (n-2) tracks on the center (n-2) tracks and arranges and records search data generated from the compressed video data on the two tracks at both ends. The search data, in the video signal per unit time, a plurality of compressed blocks at a predetermined position is extracted, the low-frequency component of the extracted compressed block is data of a predetermined amount or less, The data length to be recorded for each of the two tracks at both ends is shorter than the data length to be recorded for each of the center (n-2) tracks. At least two extraction patterns indicating the positions of the blocks are provided, and the positions of the compressed blocks in the two extraction patterns are in a complementary relationship. Is a recording / reproducing apparatus which switches at a predetermined cycle and inserts the information of the extracted pattern into search data and records the data. Is created, it is possible to prevent the resolution from deteriorating.

According to a third aspect of the present invention, a video signal per unit time is divided into a plurality of pixel blocks, and compressed video data constituted by a compression block subjected to a compression process for each pixel block is converted into a magnetic signal. N pieces on the tape (n ≧
A recording / reproducing apparatus which arranges (n-2) tracks on the center (n-2) tracks and arranges and records search data generated from the compressed video data on the two tracks at both ends. In the video signal per unit time, the search data is data obtained by reducing a low-frequency component of the compressed block extracted according to an extraction pattern indicating a position of the compressed block to be extracted to a predetermined amount or less, and the extraction pattern is At least two or more of the search data generated for each extraction pattern are detected for correlation between the compressed video data of the unit time before and the current compressed video data, and the correlation with the compressed video data of the unit time is detected. Search data generated by an extraction pattern having a low extraction pattern is used as the search data per unit time, and is recorded for each of the two tracks at both ends. The data length is shorter than the data length to be recorded for each of the (n-2) tracks at the center, so that when an image with many still images is recorded, Since only the motion component needs to be recorded with priority, high-speed reproduction with a better update rate is possible.

According to a fourth aspect of the present invention, a video signal per unit time is divided into a plurality of pixel blocks, and the compressed video data constituted by the compression blocks subjected to the compression processing in units of the pixel blocks is converted into magnetic data. N pieces on the tape (n ≧
A recording / reproducing apparatus for arranging search data generated from the compressed video data on two (2) tracks at the center, and recording the search data generated on the two end tracks on the (n-3) tracks. The search data is located at the center (n-
2) The data length generated from the compressed video data recorded on the two tracks and recorded for each of the two tracks at both ends is longer than the data length recorded for each of the (n-2) central tracks. This is a recording / reproducing apparatus characterized by being short, so that, for example, when a magnetic tape that has been subjected to insert editing is reproduced, the search data component of the erased compressed video data does not remain on the magnetic tape due to insert editing. It is possible to obtain good high-speed reproduction image quality even after editing. Further, according to a fifth aspect of the present invention, M frames per unit time (M is a natural number of 2 or more)
Is subjected to a first compression process including a basic frame for performing compression processing within a frame and a sub-frame for performing compression processing using the correlation between the frames, and the first compression processing is performed. The first compressed video data is allocated to (n-2) tracks at the center of n tracks (an integer of n ≧ 3) on the magnetic tape, and the M frame video signal is divided into a plurality of pixel blocks. The pixel blocks are extracted so as to have a predetermined number of pixel blocks, a second compression process is performed for each pixel block, and the second compressed video data that has been subjected to the second compression process is The search data is recorded on the two tracks at both ends of the n tracks, and the data length to be recorded for each of the two tracks at both ends is equal to the length of the (n-2) tracks at the center. Data length to be recorded in Ri is shorter recording reproducing apparatus according to claim, Thus, the basic frame can be recorded even subframe as the search data, it is possible to obtain a good recording and reproducing apparatus of the update rate. Also, at relatively low speed reproduction of about 10 times, the search data of the basic frame recorded on the center track and the subframes recorded at both ends can be obtained, so that the renewal rate of the reproduced image can be improved.

According to a sixth aspect of the present invention, an M
A first compression process is performed to include a basic frame for compressing a video signal of a frame (M is a natural number of 2 or more) within a frame and a subframe for performing a compression process using correlation between the frames. , N pieces of the first compressed video data on the magnetic tape (n
(Integer of ≧ 3) in the center (n-2) tracks of the track, divide the subframe into a plurality of pixel blocks, and extract the pixel blocks so as to have a predetermined number of pixel blocks; A second compression process is performed for each pixel block, and the second compressed video data subjected to the second compression process is arranged as search data in two tracks at both ends of the n tracks. Record the two ends
The data length recorded for each track of the book is (n)
-2) A compressed frame obtained by dividing a video signal into a plurality of pixel blocks and performing compression processing in units of the pixel blocks, wherein the basic frame of the first compressed video data is shorter than the data length recorded for each track. And detects the correlation between the pixel block of the basic frame and the pixel block of the sub-frame at the screen position corresponding to the basic frame, and gives priority to the pixel block of the sub-frame having a low correlation.
This is a recording / reproducing apparatus characterized in that it is assigned to a pixel block for which compression processing is performed. With this, only video data of a sub-frame having a motion component can be recorded as search data, thereby further improving the update rate of a high-speed reproduced image. It is possible to

Further, the seventh invention of the present invention provides the first to seventh embodiments.
From the n (n ≧ 3 integer) tracks on the magnetic tape recorded by the recording / reproducing apparatus of the invention, the compressed video data recorded on the central (n−2) tracks is reproduced. 1 playback means, second playback means for playing back search data recorded on two tracks at both ends, and first memory for recording the compressed video data played back by the first playback means. A second memory for recording the search data reproduced by the second reproducing means; and reproducing the compressed video data read from the first memory and the search data read from the second memory. Switching means for switching and outputting the compressed video data or the search data output from the switching means, the switching means switching in accordance with a speed; If the reproduction is performed at a higher reproduction speed, the search data is output.If the reproduction is performed at a reproduction speed lower than the predetermined reproduction speed, the compressed video data is output. In the case of shifting to a speed higher than the playback speed of the compressed video data, the search data is immediately switched to the search data, and the speed is shifted from a speed higher than the predetermined playback speed to a speed lower than the predetermined playback speed. Is a recording and reproducing apparatus characterized in that after a predetermined time has elapsed, the search data is switched to the compressed video data and output,
As a result, at the time of high-speed reproduction, the compressed video data recorded in the center (n-2) tracks in a sync block having a relatively long data length cannot be obtained. In case,
It is possible to solve the problem that the image acquired in the first low-speed search is output.

According to an eighth aspect of the present invention, there are provided n (n) pieces on a magnetic tape recorded by the first to seventh recording / reproducing apparatuses.
The first of which reproduces the compressed video data recorded on the center (n-2) tracks from the track of (≧ 3 integer).
, A second reproducing means for reproducing search data recorded on two tracks at both ends, and a switch for switching and outputting the compressed video data and the search data in accordance with a reproduction speed. Means, a memory for storing output data of the switching means, and a restoration means for restoring the compressed video data or the search data read from the memory, wherein the switching means has a reproduction speed higher than a predetermined speed. And the compressed video data is output when the data is reproduced at a reproduction speed lower than the predetermined speed. In some cases, compressed video data recorded in the center (n-2) tracks in a sync block having a relatively long data length cannot be obtained. If the transition is made to a high-speed search and then to a low-speed search, the problem that the image acquired in the first low-speed search is output is solved, and switching between the compressed video data and the search data is also performed immediately. It is possible to remove the discomfort of displaying images at the time of high-speed reproduction.

(Embodiment 1) In the present embodiment, 6.
A narrow track format in a broadcast VTR using a 35 mm tape will be described as an example. The broadcast VTR of this embodiment uses a tape having a tape width of 6.35 mm.
Attach one pair of heads to a 21.7 mmΦ rotating cylinder, rotate at 9000 rpm (round per minutes) and
One frame of video that is the basic unit of TSC video data
A segment recording method in which the data is divided into zero tracks and recorded is adopted. Tape feed speed is 33.8mm / sec
The recording is performed at a helical track pitch of 18 μm. See SMPTE (Society of Motion Picture
and Television Engineers) See standard D-7 format.

The video information to be recorded is a video signal compressed to about 25 Mbps and an audio data of about 1.5 Mbps, an ECC (Error Correcting Code) code, and a SYNC.
(Synchronous), ID data indicating information related to video information are added, and the total recording rate is 41.85 Mbps.
It is recorded in.

In the case of the broadcast VTR according to the present embodiment, the track width substantially required for recording and reproduction is about 9 μm, and the reproduction of the video is considered while considering compatible reproduction, output fluctuation and performance variation due to envelope fluctuation, environmental change and the like. The track pitch is set to 18 μm in consideration of editing. At the current track pitch of 18 μm, even if the linearity of the track (the deviation width at the time of recording) is 3 μm, the trajectory of the head (accuracy of mounting height), the environmental change, and the output variation, compatible reproduction via different VTRs Even if the compatible editing is performed, the recording track width can be reproduced at 9 μm in the worst case, and the editing function is guaranteed.

Here, the video signal to be recorded is converted to a high definition HD.
Considering the development in recording a signal, a method has been devised for compressing an HD original signal to 100 Mbps so as to be realized by signal processing for four channels of a broadcast VTR that is currently in practical use. In this case, in order to record at a track pitch of 18 μm, the feed speed of the tape is 135.2 mm / sec, the feed cylinder rotates at 9000 rpm, and recording is performed with four pair heads. The number of recording tracks per frame is 40
It is a book. If recording is performed at a track pitch of 18 μm, sufficient reproduction performance can be obtained even if a track becomes thin due to editing or the like, but the disadvantage is that the recording time is reduced to ４. In order to record the format of a broadcast VTR compatible with HD for a long time, when a narrow track recording with a track width of １ ／ is performed, the tape speed is reduced to ６７ of 67.6 m.
The vehicle is run at m / sec and recording is performed at a track pitch of 9 μm. Track pitch is 9μ which is half of current broadcasting VTR
The decrease in the S / N ratio of the reproduced signal due to the setting of m is addressed by doubling the data length of the sync block and doubling the error correction code to enhance error correction.

Specifically, in a conventional broadcast VTR, 77
Although the 8-word error correction code is added to the word data, in the present embodiment, the 1-word data is added to the 154-word data.
A 6-word error correction code is added. With such a configuration, the error correction performance is enhanced with the same data amount. This is done by taking the whole code word large,
This is because the randomness increases.

FIG. 1 shows a track format recorded on a magnetic tape by the recording / reproducing apparatus of the present embodiment.

As shown in the figure, in the track pattern of the present embodiment, one frame of compressed video data is concentrated on 38 tracks out of 40 tracks. When the number of tracks to be recorded is reduced by two, the amount of information to be recorded on one track increases by that much, and short-wavelength recording is performed. However, as in the case of recording an HD signal on a broadcast VTR, one frame is reduced by 40 frames. When segment recording is performed by dispersing the data on a large number of tracks, the decrease in recording wavelength is insignificant at (38/40), and the recording / reproducing performance is not reduced by shortening the wavelength.

At both ends of the tracks, search data dedicated to high-speed reproduction which does not matter even if erased during editing is recorded. The sync block for recording the search data is recorded as a sync block of 45 words in total by adding an error correction code of 8 words, a sync word of 2 words, and an ID of 4 words to the search data of 29 words.
As a result, since the search data is recorded on both tracks corresponding to the editing start track and the editing end track, the editing does not affect the compressed video data.

A sync block having a length of 175 words is recorded in the center track, and the playback speed at which the sync block data in which the search data is arranged can be obtained is approximately four times the playback speed at which the sync block at the center track can be obtained. Become. The number of sync blocks in the two tracks at both ends is 1
Since 304 sync blocks are recorded per track, the total is 608.

Next, the compressed video data of the broadcast VTR will be described. FIG. 2 is a block diagram showing a flow of generating compressed video data. The HD signal has a luminance signal (hereinafter abbreviated as Y signal) 1920 pixels and a color difference signal (hereinafter abbreviated as Pb and Pr signals) 960 pixels per horizontal line.
The effective line is 1080 lines.

As shown in FIG. 2, first, the HD signal is inputted to the pixel conversion means 20 and is subjected to pixel conversion by digital filter processing. The pixel conversion converts the Y signal of 1280 pixels and the Pr and Pb signals into 640 pixels per horizontal line. When converted into a frequency band, the Y signal in the 30 MHz band is converted into the Y signal in the 20 MHz band. The converted and band-limited video data is input to the blocking unit 21, and the Y signal, the Pr and the Pb signals, eight consecutive pixels in the horizontal direction, and eight consecutive pixels in the vertical direction are collectively blocked as one pixel block. Be transformed into FIG. 3 is a schematic diagram of the pixel block after blocking.

FIG. 3A is a schematic diagram of a pixel block of a Y signal, and FIG. 3B is a schematic diagram of a pixel block of a Pr and Pb signal. For example, (1, 0) of the reference numeral in the figure is the first pixel block in the vertical direction and indicates the 0th pixel block in the horizontal direction. As shown in FIG.
1600, Pr and Pb signals are 108 per screen
It is composed of 00 pixel blocks. The pixel block generated by the blocking unit 21 is input to the orthogonal transformation unit 22, and DCT (Discrete Cosine Transcription) is performed for each pixel block.
(sform). As shown in FIG. 2, the orthogonally transformed video data is input to the encoding unit 23, subjected to variable length encoding processing such as Huffman coding, and output as compressed video data. In the present process, since the orthogonal transformation process and the encoding process are performed for each pixel block, the number of pixel blocks per frame and the number of compressed blocks are the same.

The Y signal, Pr, and Pb signals, which have been subjected to the compression processing as described above, include 4320 signals per frame.
The operation of the present embodiment using compressed video data composed of zero compression blocks as an input signal will be described below.

FIG. 4 is a block diagram showing the configuration of the recording / reproducing apparatus according to this embodiment.

In FIG. 4, reference numeral 40 denotes an input terminal for inputting compressed video data, 41 denotes a macroblock forming means for converting the compressed video data inputted from the input terminal 40 into macroblocks, and 42 denotes a macroblock from the macroblock forming means 41. A compressed data converter 43 for converting the compressed compressed video data into search data, adding an error correction code to the compressed video data input from the input terminal 40, performing a modulation process, and outputting the first modulated data The first recording processing means 44 converts the search data output from the compressed data conversion means 42 into second modulated data and outputs the second modulated data.
The recording processing means 45 selects the second modulated data for the two tracks at both ends and the first modulated data for the central (n-2) tracks in n tracks per frame. Selection means, 46 is a recording amplifier, and 47 is a recording head for recording data on a magnetic tape 48.

The compressed video data input to the input terminal 40 is input to the macroblocking means 41, where four Y compressed blocks adjacent in the horizontal direction and two Pr and Pb adjacent in the horizontal direction are used. The compressed block is output as one unit of macroblock. Therefore, the number of macroblocks per frame is 5,400.

FIG. 5 is a conceptual diagram of a macro block. For example, the code (0, 0) shown in the figure is the same as the code in FIG. 3, and indicates the 0th compressed block in the horizontal direction and the 0th compressed block in the vertical direction.

The compressed video data that has been macroblocked by the macroblocking means 41 is input to the compressed data conversion means 42 and converted into search data. The conversion method to the search data is to extract the DC component of each compressed block, perform an average value processing of four DC components in the case of a Y signal, output the upper 8 bits thereof, and output a Pr or Pb signal. For example, the top 6 data obtained by averaging two DC components
The bits are output as search data. Therefore, the search data of one macroblock is composed of 20 bits.

On the other hand, the compressed video data input from the input terminal 40 is input to the first recording processing means 43, and is output as first modulated data subjected to error correction code addition and modulation processing. As described above, the configuration of the first modulation data is a configuration in which an error correction code of 16 words is added to 154 words of data.

FIG. 6 shows a configuration diagram of a sync block for search data. As shown in FIG. 6, each data output from the compressed data conversion means 42 is composed of 20 bits.
A total of 5400 search data are input to the second recording processing means 44, and the 10 search data are combined into one, and 200 bits (1 word is 8 bits, which is 25 words) and an error of 8 words is obtained. The data is mapped to a sync block constituted by a correction code and output as second modulated data.

As described above, 5400 pieces of search data are 1
Although 0 is arranged in 540 sync blocks each, in this embodiment, 608 sync blocks can be used per frame as a search data storage area.
Therefore, the 68 sync blocks arrange the data at the center of the screen again to increase the data acquisition rate during high-speed playback.

The first modulation data and the second modulation data are inputted to the selecting means 45, and two tracks at both ends of the n tracks per frame are the second modulation data and the center (n-2). ) The book track is output as recording data selected to be the first modulation data.
The recording data output from the selection means 45 is recorded on a magnetic tape 48 by a recording head 47 via a recording amplifier 46.

As described above, according to the present embodiment, search data is arranged in a sync block having a short sync block length for high-speed reproduction and recorded on two tracks at both ends. Only the search data arranged on the tracks at both ends of the book becomes available, and editing in the narrow track format becomes possible. Also, in high-speed playback,
Since the data having a short data length and covering the screen per unit time is arranged in two tracks as search data, the image update rate during high-speed reproduction does not decrease.

(Embodiment 2) The difference between this embodiment and Embodiment 1 is the method of creating search data.

Hereinafter, the present embodiment will be described with reference to FIG.

FIG. 7 is a block diagram showing the configuration of the recording / reproducing apparatus according to the present embodiment.

In FIG. 7, reference numeral 70 denotes a block extracting means for extracting a compressed block from input compressed video data with reference to an extraction pattern 71, and reference numeral 72 denotes search data from the compressed block extracted by the block extracting means 70. Search data generating means 73 is a recording means for recording recording data obtained by inserting pattern information into the data generated by the search data generating means 72.

The compressed video data is input to the block extracting means 70, and a compressed block of the compressed video data is extracted with reference to the extraction pattern 71. In the present embodiment, two types of extraction patterns, pattern 0 and pattern 1, are prepared, and pattern 0 and pattern 1 are switched for each frame. FIG. 8 shows pattern 0, pattern 1 and TV
In this embodiment, a pattern 0 and a pattern 1 are set so as to have a complementary relationship. By doing so, the search data corresponding to the entire screen position is 2
It is recorded at the frame cycle.

The compressed block extracted by the block extracting means 70 is input to the search data creating means 72,
Two compressed blocks adjacent to Y and one compressed block of each of Pr and Pb are converted into macroblocks. Further, the DC component of each compressed block is extracted as 8-bit data of Y and Pb and Pr are extracted as 6-bit data, and Y is output as 20-bit search data by taking the average value of the DC components of two adjacent blocks. are doing. In the present embodiment, since the number of compressed blocks is reduced by half by the block extracting means 70, the macroblock for which search data is created corresponds to half the screen size of the first embodiment.

The search data created by the search data creation means 72 is input to the recording means 73. The recording unit records the recording data in which the pattern information is inserted into the ID of the sync block. The pattern information indicates, for example, a pattern number and may be any information as long as the extraction pattern can be specified. The configuration method of the sync block is the same as that of the first embodiment, and the description is omitted.

As described above, according to the present embodiment, search data is created by extracting frame by frame from a compressed block located at a complementary screen position for each frame. TV corresponding to data
The size of the screen can be made smaller than that of the first embodiment, and it is possible to prevent the resolution from deteriorating during high-speed reproduction in the narrow track format.

In this embodiment, two patterns are used as the extraction patterns. However, the present invention is not limited to this, and three or more extraction patterns may be used. In that case, it is desirable that each pattern is at a complementary screen position.

(Embodiment 3) This embodiment is different from Embodiments 1 and 2 in the method of creating search data.

Hereinafter, the present embodiment will be described with reference to FIG.

FIG. 9 is a block diagram showing the configuration of the recording / reproducing apparatus according to the present embodiment.

In FIG. 9, the same reference numerals are assigned to blocks performing the same operation as in the embodiment, and the description will be omitted.
In the figure, reference numeral 74 denotes a memory for temporarily storing the data output from the comparing means 75, and 75 denotes a comparing means for comparing the data output from the search data generating means 72 with the data stored in the memory 74. .

FIG. 10 shows an extraction pattern of the present embodiment corresponding to FIG. 8 of the second embodiment. As shown in the figure,
Pattern 0 extracts blocks located at the top of one frame, and pattern 1 extracts blocks located at the bottom of one frame.

The method of creating search data in the present embodiment is different for the first frame, the second frame, the third frame, and so on, so the algorithm will be described first.

(1) In the first frame, search data corresponding to pattern 0 is recorded.

(2) In the second frame, search data corresponding to pattern 1 is recorded.

(3) After the third frame, the search data recorded at the closest time is compared with the search data of the current frame, and the search data corresponding to the pattern having the larger difference is recorded for each macro block.

The above is the outline of the algorithm.

First, the compressed video data of the first frame is
DC data is extracted from the macroblock corresponding to the pattern 0 in FIG. 10 and input to the search data creating means 72 to create search data. The method of creating the search data is the same as that of the second embodiment, and a description thereof will be omitted. The search data generated by the search data generating means 72 is
5 is input. The comparing means 75 does not perform any operation in the first frame. The data output by the comparing means 75 is recorded in the memory 74 and is also input to the recording means 73 and output as recording data. The compressed video data of the second frame is input to the search data creation means 72, and DC data is extracted from the macroblock corresponding to pattern 1 in FIG. 10 to create search data. The search data generated by the search data creation means 72 is
Is input to The comparing means 75 performs no operation in the second frame. The data output by the comparing means 75 is recorded in the memory 74 and is also input to the recording means 72 and output as recording data. The compressed video data of the third and subsequent frames is input to the search data creating means 72, and extracts DC data from macroblocks corresponding to both pattern 0 and pattern 1 in FIG. 10 to create search data. Pattern 0 generated by search data generating means 72
The search data corresponding to both the pattern 1 and the pattern 1 are input to the comparing means 75. The comparing means 75 compares the search data stored in the memory 74 with the search data output from the search data creating means 72.
Since the comparison is a comparison of the DC components of the compressed video data, an absolute value comparison is sufficient. Absolute value comparison is pattern 0 and putter 1
The absolute value is compared one macroblock at a time from among the macroblocks corresponding to, and the search data of the pattern with the larger absolute value is output from the comparing means 75 as priority data. The priority data output by the comparing means 75 is recorded in the memory 74 and is also input to the recording means 72 and output as recording data.

As described above, in the present embodiment,
The search data recorded at the closest time is compared with the current search data, and the one having the larger absolute value of the DC component of the compressed video data, that is, the block with the larger motion is preferentially recorded. High-speed reproduction with a better update rate is possible.

In this embodiment, two patterns are used as extraction patterns. However, the present invention is not limited to this, and three or more extraction patterns may be used. In that case, it is desirable that each pattern is at a complementary screen position.

(Embodiment 4) In the present embodiment, the search data arranged on the two tracks at both ends per unit time is (n-2) at the center of the search tracks at both ends.
It is characterized by being generated from compressed video data arranged on a track of a book. Since Embodiments 1 to 3 are also described according to the present invention, description of the circuit configuration is omitted in this embodiment.

Another technique not disclosed in the second embodiment is, for example, a technique in which compressed data of one frame is stored in a memory, and one frame is read out half by one, converted into search data and recorded. Conceivable. In this case, the compressed video data is extracted by one frame every two frames on the TV screen, and the extracted compressed video data of one frame is divided into two frames on a magnetic tape and recorded on four tracks.

A problem that occurs when a magnetic tape recorded in the above-described form and subjected to insert editing on a magnetic tape is reproduced at high speed will be described with reference to FIG.

In FIG. 11, a thin block indicates a track for recording two pieces of search data, and a thick block indicates a center (n-2) track. FIG. 3A is a schematic diagram of a magnetic tape in which search data per frame is recorded in two frames of the magnetic tape.
0, A1, A2, and A3 identify the frame. The figure shows that the search data is created from the frames A0 and A2. FIG. 3B is a schematic diagram of video data to be insert-edited, and B0, B1, B2, and B3 identify frames. In the figure, the search data is B0,
Indicates that it is created from the frame of B2. (C) of the figure is a schematic diagram showing the data of the magnetic tape after the insert editing, in which video data corresponding to B1 and B2 in the figure (b) is insert-edited to A1 and A2 in the figure (a). It is.

As shown in the figure, the compressed video data recorded on the tape after insert editing is A0, B1,
B2, A3, and the search data recorded on the tape after the insert editing are A0, B0, B2, A2, and the search data of a frame different from the frame of the compressed video data is recorded. When a magnetic tape on which insert editing has been performed is reproduced at a high speed, an image different from the compressed video data recorded on the magnetic tape is output.

According to the present invention, the search data arranged on the two tracks at both ends per unit time is generated from the compressed video data arranged on the (n-2) tracks at the center of the two search tracks at both ends. I do.

FIG. 12 is a schematic view of a magnetic tape on which insert editing has been performed in the recording / reproducing apparatus of the present invention. In FIG. 12, thin blocks indicate tracks on which two pieces of search data are recorded, and thick blocks indicate central tracks ( n-2) Indicates a track. FIG. 1A shows a recorded magnetic tape, and A0, A1, A2, and A3 identify frames. In the figure, search data is created from each frame. FIG. 3B is a schematic diagram of video data to be insert-edited, and B1, B2, B3, and B4 identify frames. Also in this figure, search data is created from each frame. FIG. 11C is a schematic diagram of the magnetic tape after the insert editing. As shown in FIG. 10C, the frames of the compressed video data and the search data match after the insert editing. The above-mentioned problems can be solved.

As described above, according to the present embodiment, the search data to be arranged on the two tracks at both ends per unit time is the (n−2) data at the center of the two search tracks at both ends. If it is generated from the compressed video data arranged on the track, for example, when a magnetic tape that has been subjected to insert editing is reproduced, the search data component of the deleted compressed video data does not remain on the magnetic tape due to insert editing, and after editing, However, since the compressed video data and the search data are always located at the same frame position on the magnetic tape, it is possible to obtain good high-speed reproduction image quality.

The search data to be recorded in the first track of the n tracks to be recorded per unit time is created from the compressed video data to be recorded in the first half of the (n-2) tracks per unit time, and n If the search data to be recorded in the last track of the tracks is created from the compressed video data to be recorded in the second half track of the (n-2) tracks, the search data is stored and stored in the two tracks at both ends. Needless to say, the memory required for recording can be halved.

(Embodiment 5) In the present embodiment, a basic frame for compressing M (M is a natural number of 2 or more) frames of video signals per unit time in a frame and a correlation between the frames are used. The compressed video data that has been subjected to compression processing to include the
2) The data is recorded on the tracks, the video signal of the sub-frame is subjected to compression processing to generate search data, and the search data is recorded on the two tracks at both ends.

FIG. 13 is a block diagram showing the configuration of the recording / reproducing apparatus according to the present embodiment. In the figure, the same numbers are given to blocks performing the same operations as those of the recording / reproducing apparatus in Embodiment 1, and the description is omitted.

In FIG. 13, reference numeral 80 denotes an input terminal for inputting a video signal, 81 denotes first compression means for compressing the video signal input from the input terminal 80, and 82 denotes a video signal input from the input terminal 80. A sub-frame extracting unit 83 for extracting a sub-frame is provided in advance from the sub-frame output by the sub-frame extracting unit 82, but is a pixel block extracting unit for extracting a pixel block according to a pattern. 84 is an output from the pixel block extracting unit 83. A second compression unit that compresses the obtained pixel block and outputs it as search data.

The video signal applied to the input terminal 80
Input to 1 compression means. The first compression means is MPEG
2 (Motion Picture Expert Group) GOP (Group O
f Picture) is compressed by 2 (M = 2). GOP is 2
In the case of, the frame is composed of a basic frame compressed in a frame and a subframe obtained by compressing difference data between the preceding and succeeding basic frames. In other words, for each frame, the basic frame,
It has a configuration such as a subframe, a basic frame, a subframe.

On the other hand, the video signal is supplied to the subframe extracting means 8.
2, a frame corresponding to the sub-frame of the first compression unit 81 is extracted, and the pixel block extraction unit 83 extracts a pixel block according to a previously prepared pattern as described in the second embodiment. ing. The extracted pixel blocks are input to the second compression means 84, compressed to take an average value for each pixel block, and output as search data.

The compressed video data outputted from the first compression means 81 is sent to the first recording processing means 43, and the search data outputted from the second compression means 84 is sent to the second recording processing means 44. The data is input to the selection unit 45 as first recording data and second recording data, respectively. The selecting means 45 selects the second recording data for the two tracks at both ends and the first recording data for the other tracks, and the data output from the selecting means 45 is passed through the recording amplifier 46 by the recording head 47 to the magnetic tape. Recorded at 48.

Next, reproduction of data recorded on the magnetic tape as described above will be described. The signal processing on the reproduction side is classified into three types. That is, (1) normal reproduction in which all data is obtained, (2) special reproduction in which a part of the data is obtained, a predetermined speed or less, and (3) high-speed reproduction in which only data of two tracks at both ends can be obtained. ,.

Here, the reproduction corresponding to (1) is performed by decoding the data obtained from the center (n−2) tracks to obtain a reproduced image, and performing the special reproduction corresponding to (2). Is a reproduced image obtained by decoding and combining data corresponding to a basic frame obtained from the center (n-2) tracks and data obtained from the two tracks at both ends. In the case of high-speed playback corresponding to (3), data obtained from only two tracks at both ends having a short data length is decoded to obtain a playback image.

As described above, according to the present embodiment, the correlation between the pixel block of the basic frame and the pixel block of the sub-frame at the corresponding screen position is detected, and the pixel block of the sub-frame having a low correlation is detected. Is recorded on the search track with priority given to the sub-frame, only the video data of the sub-frame having the motion component can be recorded as the search data. Thus, it is possible to obtain a reproduced image, and to improve the update rate in special reproduction.

In this embodiment, only the data corresponding to the sub-frame is recorded on the two tracks at both ends. However, the data corresponding to the basic frame or the data corresponding to the basic frame and the sub-frame is recorded. Needless to say, this is acceptable. However, in the special reproduction, the same screen position block of the basic frame is recorded twice, so that the update rate decreases.

Further, in the present embodiment, the compression in the case where the GOP is 2, ie, M is 2, has been described, but it goes without saying that the present embodiment can be applied to cases other than the case where M is 2. In the present embodiment, the first compression means is MPEG
Although the compression was performed in step 2, the compression is not limited to this, and any compression processing including a basic frame and a subframe may be performed.

(Embodiment 6) This embodiment is an improvement on the method of creating search data in Embodiment 5. That is, the correlation between the pixel block of the basic frame and the pixel block of the sub-frame at the corresponding screen position is detected, and the pixel block of the sub-frame having a low correlation is preferentially recorded on the two tracks at both ends.

Hereinafter, the present embodiment will be described with reference to FIG. FIG. 14 is a diagram showing a configuration of a search data creation circuit according to the present embodiment. In the figure, the same reference numerals are given to blocks performing the same operations as in the fifth embodiment. In FIG. 14, reference numeral 85 denotes a basic frame extracting means for extracting a basic frame; 86, a blocking means for blocking input data;
Is a selecting means for selecting any of the input basic frame and subframe compressed data.

The video signal applied to the input terminal 80 is input to the basic frame extracting means 85 and the sub-frame extracting means 82, respectively, and the basic of the compressed video data compressed by the first compressing means described in the fifth embodiment. Frames corresponding to frames and subframes are extracted. The basic frame and the subframe extracted by the basic frame extracting unit 85 and the subframe extracting unit 82 are respectively
6 and is divided into the same pixel block as the basic frame, and, like the MPEG2 basic frame, 8 pixels continuous in the horizontal direction of the screen and 8 pixels continuous in the vertical direction of the screen are grouped into 64. The pixel is output as a unit pixel block. The pixel block blocked by the blocking means 86 is input to the second compression means,
The average value of the pixels is output as compressed data of each pixel block. The compressed data of the basic frame and the sub-frame that have been averaged by the second compression unit are input to the comparison unit 87, and the comparison unit 87 converts the compressed data (the average value of 64 pixels) of the pixel block at the same position on the screen. Difference calculation is performed, and data having a large absolute value of the difference value is preferentially output as search data.

As described above, according to the present embodiment, the correlation between the pixel block of the basic frame and the pixel block of the sub-frame at the corresponding screen position is detected, and the pixel block of the sub-frame having a low correlation is prioritized. Since the search data is used, only the video data of a sub-frame having a motion component can be recorded, so that it is possible to further improve the update rate of the high-speed reproduction image in the narrow track format.

In the present embodiment, an example has been described in which the number of sub-frames is one (M = 2). However, when M is 3 or more, the circuit is parallelized so that the selection means is the most absolute value. Needless to say, it is only necessary to output the compressed data of the sub-frame having the larger value as the search data.

(Embodiment 7) The present embodiment relates to a case where the recording medium recorded according to Embodiments 1 to 6 is reproduced.

FIG. 15 is a block diagram showing a configuration of a recording / reproducing apparatus according to the present embodiment.

In FIG. 15, reference numeral 90 denotes a reproducing head for reproducing data from the magnetic tape 48, and 91 denotes a reproducing head 90.
Amplifier for amplifying the reproduced data reproduced by
Numeral 2 denotes the data inputted from the reproduction amplifier 91, which is subjected to reproduction processing such as demodulation, error correction, etc., and data conversion processing for the data recorded on the (n-2) tracks in the center, and then to the compressed video data. The first reproducing means 93 outputs reproduction data such as demodulation and error correction and data conversion processing on the data recorded on the two tracks at both ends of the reproduction data input from the reproduction amplifier 91. Thereafter, second reproducing means 94 for outputting as search data, switching means 94 for switching and outputting data output by the first reproducing means and data output by the second reproducing data according to the reproducing speed, and 95 for switching Decoding means for decoding the data output from the means 94; 96, an output terminal for outputting the video signal output from the decoding means 95; 97, an output terminal for outputting the video signal from the first reproducing means. First for recording compressed video data that
And 98, a second memory for recording search data output from the second reproducing means.

The reproduced data reproduced from the magnetic tape 48 by the reproducing head 90 is amplified by the reproducing amplifier 91 and inputted to the first reproducing means 92 and the second reproducing means 93. In the first reproducing means 92, (n-
2) Playback processing such as demodulation and error correction, and data conversion processing are performed on the playback data recorded on the track, and then output as compressed video data. Here, the data conversion processing indicates rearrangement as compressed video data, synchronization signal addition processing, and the like. The second reproducing means 93 performs reproduction processing such as demodulation and error correction and data conversion processing on the reproduction data recorded on the two tracks at both ends, and then outputs the data as search data. The data conversion processing in the second reproducing means 93 is the same as that of the first reproducing means 92, and performs the rearrangement processing, the addition of the synchronization signal, and the like.
The compressed video data output from the first reproducing means 92 and the search data output from the second reproducing means 93 are recorded in the first memory 97 and the second memory 98, respectively, and
Are read out by the reproducing means 92 and the second reproducing means 93. The switching means 94 outputs the compressed video data read from the second memory 97 at a reproduction speed lower than the predetermined speed, and outputs the second memory 9 at a reproduction speed higher than the predetermined speed.
8 to output the search data read. The data output from the switching means 94 is decoded by the restoration means 95,
It is output from the output terminal 96 as a video signal.

In reproducing a magnetic tape, the reproducing head reproduces over a plurality of tracks in one scan, so that the data that can be acquired per track decreases in proportion to the reproducing speed. Go. Therefore, the predetermined speed is set to a reproduction speed at which data of one sync block of the (n-2) tracks at the center cannot be continuously obtained. Since the two tracks at both ends have a short sync block length, data can be obtained in sync block units even during high-speed playback. That is, a memory 98 for recording search data
, The data is always recorded, but the data for the compressed video data memory 97 is not updated at all at a high speed reproduction higher than a predetermined speed.

For example, assuming that the predetermined speed is 10 × speed playback, when the playback speed shifts as in 10 × speed playback, 20 × speed playback, and 5 × speed playback, the memory 97 is not updated in 20 × speed playback, so that the 5 × speed playback is performed. When the data recorded in the memory 97 is read at the moment when the reproduction is shifted to,
Data recorded at the time of 10 × speed reproduction is read. At the time of 20 × speed reproduction, data recorded in the memory 98 is read, and in this case, the time is reversed.

In the present embodiment, when shifting from a speed higher than the predetermined reproduction speed to a speed lower than the predetermined reproduction speed, the search data stored in the second memory 98 is recorded in the first memory 97 after the predetermined time has elapsed. The compressed video data is switched and output.

In the present embodiment, search data is output when reproduced at a reproduction speed higher than a predetermined speed, and compressed video data is output when reproduced at a reproduction speed lower than the predetermined speed. In the case of shifting from a speed higher than the speed to a speed lower than the speed, if the search data is switched to the compressed video data after a predetermined time elapses, at the time of high-speed reproduction, the center (n- 2) Since the compressed video data recorded on the track cannot be obtained, when the transition from the low-speed search to the high-speed search and then to the low-speed search occurs, the image obtained in the first low-speed search is output. Can be solved.

The predetermined time may be changed according to the reproduction speed. That is, the memory 97 can be entirely updated if one frame is reproduced in low-speed reproduction, and at least 10 frames are required to update the memory in 10-times reproduction.

As described above, according to the present embodiment, it is possible to reproduce a magnetic tape recorded in a narrow track format at a wide range of speeds, and to cope with a change in the reproduction speed.

(Embodiment 8) FIG. 16 is a block diagram showing a configuration of a recording / reproducing apparatus according to the present embodiment.

In the figure, the same reference numerals are given to blocks performing the same operation as in the seventh embodiment, and the description is omitted.
In FIG. 16, reference numeral 99 denotes a memory for storing data output from the switching means 94.

The reproduced data reproduced by the reproducing head 90 from the magnetic tape 48 is amplified by the reproducing amplifier 91 and is inputted to the first reproducing means 92 and the second reproducing means 93. In the first reproducing means 92, (n-
2) The reproduction data recorded on the track is subjected to reproduction processing such as demodulation and error correction and data conversion processing, and then output as compressed video data. Further, the second reproducing means 93 performs reproduction processing such as demodulation and error correction and data conversion processing on the reproduction data recorded on the two tracks at both ends, and outputs the data as search data. The data conversion processing includes rearrangement processing, synchronization signal addition, and the like. The switching unit 94 outputs the compressed video data output from the first playback unit 92 at a playback speed lower than the predetermined speed, and outputs the compressed video data from the second playback unit 93 at a playback speed higher than the predetermined speed. Output search data. The data output from the switching means 94 is recorded in the memory 99. The data recorded in the memory 99 is read by the restoring means 95 and output from the output terminal 96 as a video signal.

FIG. 17 is a diagram showing transition of data stored in the memory 99.

The hatched blocks in the figure indicate the pixel blocks in which the compressed image data has been restored, and the white blocks indicate the pixel blocks in which the search data has been restored. FIG.
Correspondence between screen and pixel block during double-speed playback, FIG.
FIG. 4 is a correspondence diagram between a screen and a pixel block at the moment of transition from 10 × speed reproduction to 30 × speed reproduction, and FIG. 4C is a correspondence diagram of a screen and a pixel block after a lapse of a predetermined time after transition to 30 × speed reproduction. As shown in the figure, since the image of the compressed video block can be output immediately even at the time of transition, the seventh embodiment can be used.
As described above, the complexity of switching after waiting for a predetermined time when switching circuits can be eliminated.

In this embodiment, if a memory for storing the output data of the switching means is added, and the data read from the memory is decoded and output as a video signal, the switching between the compressed video data and the search data is also performed immediately. It is possible to eliminate the complexity of signal processing.

In the present embodiment, compressed video data and search data are switched and recorded according to the speed.
It goes without saying that all of the obtained compressed data and search data may be recorded in the memory at a predetermined speed or lower.
In this case, when the pixel block data at the same position is acquired, it is needless to say that either one of them may be recorded in the memory.

Although the present invention has been described for the case where the number of tracks is n = 40, the present invention is not limited to this.

Although the present invention has been described only for the case of a broadcast VTR conforming to the SMPTE standard D-7 format, the present invention is not limited to this. The configuration such as the recording head of the broadcast VTR is not limited to this.

The track pitches of the normal track format and the narrow track format are 18 μm and 9 μm.
However, the present invention is not limited to this, and any track pitch may be used as long as it can guarantee reproduction and editing functions.

Although the present invention has been described for video data only, it is clear that the present invention is applicable to audio data and other cases. And n (n−
2) It is possible to respond by selecting a book.

[0113]

As described above, according to the present invention, search data is arranged in a sync block having a short sync block length for high-speed reproduction and recorded on two tracks at both ends.
The effect of the thin track at the time of editing is only the search data arranged on the two tracks at both ends, so that editing in the narrow track format becomes possible. Also, in high-speed reproduction, data that can cover a screen per unit time with a short data length is arranged as search data in two tracks, so that the image update rate during high-speed reproduction does not decrease.

[Brief description of the drawings]

FIG. 1 is a schematic view of a track recorded on a magnetic tape of the present invention.

FIG. 2 is a configuration diagram of a compressed video data generation circuit according to the present invention.

FIG. 3 is an explanatory diagram of a pixel block according to the present invention.

FIG. 4 is a block diagram showing a configuration of a recording / reproducing apparatus according to Embodiment 1 of the present invention.

FIG. 5 is an explanatory diagram of a macroblock according to the present invention.

FIG. 6 is a configuration diagram of a sync block recorded on both end tracks according to the present invention.

FIG. 7 is a configuration diagram of a search data generation circuit according to a second embodiment of the present invention.

FIG. 8 is an explanatory diagram of an extraction pattern according to the second embodiment of the present invention.

FIG. 9 is a configuration diagram of a search data generation circuit according to a third embodiment of the present invention.

FIG. 10 is an explanatory diagram of an extraction pattern according to the third embodiment of the present invention.

FIG. 11 is an explanatory diagram of a problem at the time of editing according to the fourth embodiment of the present invention.

FIG. 12 is an explanatory diagram of a problem solving method at the time of editing according to the fourth embodiment of the present invention.

FIG. 13 is a block diagram showing a configuration of a recording / reproducing apparatus according to Embodiment 5 of the present invention.

FIG. 14 is a configuration diagram of a search data generation circuit according to a sixth embodiment of the present invention.

FIG. 15 is a block diagram showing a configuration of a recording / reproducing apparatus according to Embodiment 7 of the present invention.

FIG. 16 is a block diagram showing a configuration of a recording / reproducing apparatus according to Embodiment 8 of the present invention.

FIG. 17 is a schematic diagram showing a screen update at the time of transition of the reproduction speed in the eighth embodiment of the present invention.

FIG. 18 is a diagram showing a problem in editing a conventional narrow track format.

[Explanation of symbols]

 40, 80 input terminals 41 macroblocking means 42 compressed data conversion means 43 first recording processing means 44 second recording processing means 45 selection means 46 recording amplifier 47 recording head 71 extraction pattern 70 block extraction means 72 search data creation means 73 recording means 74,99 memories 75,87 comparing means 82 subframe extracting means 83 pixel block extracting means 84 second compressing means 85 basic frame extracting means 86 blocking means 90 reproducing head 91 reproducing amplifier 92 first reproducing means 93 Second reproducing means 94 Switching means 95 Restoring means 96 Output terminal 97 First memory 98 Second memory

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H04N 5/91 H04N 5/91 N 5/93 5/93 Z 7/30 7/133 A (72) Inventor Hirofumi Uchida 1006, Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. GA16 GB05 GB07 GB08 GB15 GB38 HA24 HA29 5C059 KK36 MA05 MC23 MC34 RB02 RC14 RF04 SS11 SS17 SS19 TA17 TC47 TD13 UA02 UA38 5D044 AB07 BC01 CC03 DE14 DE17 DE49 EF05 FG24 GK08

Claims (11)

[Claims] 1. A video signal per unit time is divided into a plurality of pixel blocks, and compressed video data constituted by compressed blocks subjected to a compression process in units of the pixel blocks is divided into n (n) pieces of data on a magnetic tape. (Integral of ≧ 3), a recording / reproducing apparatus for arranging in the center (n-2) tracks and arranging and recording search data generated from the compressed video data in two tracks at both ends. The search data is data in which a low-frequency component of a compressed macroblock obtained by collecting a plurality of the compressed blocks adjacent to each other on a screen is equal to or less than a predetermined amount. The data length for recording search data and recording for each of the two tracks at both ends is shorter than the data length for recording for each of the center (n-2) tracks. Apparatus. 2. A video signal per unit time is divided into a plurality of pixel blocks, and compressed video data composed of compressed blocks that have been subjected to a compression process on a pixel block basis is divided into n (n) pieces on a magnetic tape. (Integral of ≧ 3), a recording / reproducing apparatus for arranging in the center (n-2) tracks and arranging and recording search data generated from the compressed video data in two tracks at both ends. The search data is data obtained by extracting a plurality of compressed blocks at a predetermined position in the video signal per unit time and reducing a low-frequency component of the extracted compressed blocks to a predetermined amount or less. The data length recorded for each of the two tracks at both ends is shorter than the data length recorded for each of the (n-2) central tracks. Location. 3. A video signal per unit time, comprising at least two extraction patterns indicating positions of compressed blocks to be extracted, wherein the positions of the compressed blocks in the two extracted patterns are in a complementary relationship, 3. The recording / reproducing apparatus according to claim 2, wherein the extraction pattern is switched at a predetermined cycle, and information of the extraction pattern is inserted into search data and recorded. 4. A video signal per unit time is divided into a plurality of pixel blocks, and compressed video data composed of compressed blocks that have been subjected to a compression process in units of the pixel blocks are divided into n pieces (n) on a magnetic tape. (Integral of ≧ 3), a recording / reproducing apparatus for arranging in the center (n-2) tracks and arranging and recording search data generated from the compressed video data in two tracks at both ends. The search data is data obtained by reducing a low-frequency component of the compressed block extracted according to an extraction pattern indicating a position of a compressed block to be extracted to a predetermined amount or less in the video signal per unit time; There are at least two or more compressed video data of the unit time before and the current compressed video data with respect to the search data generated for each of the extracted patterns. A search data generated by an extraction pattern having a low correlation with the compressed video data before the unit time, as search data per unit time, and a data length to be recorded for each of the two tracks at both ends. Is shorter than the data length to be recorded for each of the center (n-2) tracks. 5. A video signal per unit time is divided into a plurality of pixel blocks, and compressed video data composed of compressed blocks that have been subjected to a compression process in units of the pixel blocks is written on n magnetic tapes (n A recording / reproducing apparatus for arranging search data generated from the compressed video data on two (2−2) tracks at the center of the (n−2) tracks, and recording the search data generated on the two end tracks. The search data is generated from the compressed video data recorded on (n-2) tracks at the center of the two tracks on which the search data is recorded; The recording / reproducing apparatus is characterized in that the data length to be recorded in the center is shorter than the data length to be recorded for each of the center (n-2) tracks. 6. Search data to be recorded in the first track of the n tracks is created from compressed video data to be recorded in the first half of the center (n-2) tracks, and the last track of the n tracks 6. The recording / reproducing apparatus according to claim 5, wherein the search data to be recorded on the second track is created from compressed video data to be recorded on the latter half of the center (n-2) tracks. 7. A basic frame for compressing a video signal of M frames (M is a natural number of 2 or more) per unit time in a frame, and a subframe for compressing the video signal using a correlation between the frames. After performing the first compression process, the first compressed video data subjected to the first compression process is transferred to the center (n−2) of n tracks (an integer of n ≧ 3) on the magnetic tape. The video signals of the M frames are divided into a plurality of pixel blocks, the pixel blocks are extracted so as to have a predetermined number of pixel blocks, and a second compression process is performed for each pixel block. The second compressed video data that has been subjected to the second compression process is recorded as search data on the two tracks at both ends of the n tracks, and is recorded for each of the two tracks at the both ends. Day to record Long, the recording and reproducing apparatus characterized by shorter than the data length to be recorded on each track of the (n-2) present the central. 8. A basic frame for compressing a video signal of M frames (M is a natural number of 2 or more) per unit time in a frame, and a subframe for compressing the video signal using correlation between the frames. The first compression processing is performed as described above, and the first compressed video data that has been subjected to the first compression processing is added to the center (n-2) of n tracks (an integer of n ≧ 3) on the magnetic tape. The sub-frames are divided into a plurality of pixel blocks, the pixel blocks are extracted so as to have a predetermined number of pixel blocks, and a second compression process is performed for each of the pixel blocks. 2 is recorded as search data using the second compressed video data that has been subjected to the compression processing of No. 2 as search data on the two tracks at both ends of the n tracks, and data recorded for each of the two tracks at both ends. The head is Serial middle (n-2) the recording and reproducing apparatus characterized by shorter than the data length to be recorded on each track of the present. 9. The basic frame of the first compressed video data is composed of a compressed block obtained by dividing a video signal into a plurality of pixel blocks and performing a compression process on a pixel block basis. And detecting a correlation with a pixel block of a sub-frame at a corresponding screen position and assigning a pixel block of a sub-frame having a low correlation to a pixel block to be subjected to the second compression processing with priority. Item 9. The recording / reproducing device according to Item 8. 10. A magnetic tape is recorded on (n-2) tracks at the center of n tracks (an integer of n.gtoreq.3) on a magnetic tape recorded by the recording / reproducing apparatus. First reproducing means for reproducing compressed video data, second reproducing means for reproducing search data recorded on two tracks at both ends, and the compressed video data reproduced by the first reproducing means. A first memory for recording
A second memory for recording the search data reproduced by the second reproducing means, the compressed video data read from the first memory, and the search data read from the second memory at a reproduction speed. Switching means for switching and outputting the compressed video data or the search data output from the switching means, wherein the switching means reproduces at a reproduction speed higher than a predetermined speed. Outputs the search data and outputs the compressed video data when reproduced at a reproduction speed lower than the predetermined speed, and shifts from a speed lower than the predetermined reproduction speed to a speed higher than the predetermined reproduction speed. In this case, the compressed video data is immediately switched to the search data and output, and the predetermined video data is output at a speed higher than the predetermined reproduction speed. When migrating to a speed slower than the playback speed, the recording and reproducing apparatus, characterized in that from the search data after a predetermined time has elapsed, switches and outputs the compressed video data. 11. Recording is performed on (n-2) tracks at the center from n tracks (an integer of n.gtoreq.3) on the magnetic tape recorded by the recording / reproducing apparatus. First playback means for playing back compressed video data, second playback means for playing back search data recorded on two tracks at both ends, and a playback speed of the compressed video data and the search data. Switching means for switching and outputting correspondingly, a memory for storing output data of the switching means, and a restoring means for restoring the compressed video data or the search data read from the memory; Outputting the search data when reproduced at a reproduction speed higher than a predetermined speed, and outputting the compressed video data when reproduced at a reproduction speed lower than the predetermined speed. Recording reproducing apparatus according to claim.