JP2002367294A - Recording method and recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a pre-read edition function which processes already recorded voice signals and records the same again in an original place even when the entire part of tracks cannot be reproduced by a preceding playback head with a digital VTR. SOLUTION: Voice data is recorded on recording tracks in a region nearest the terminal section with respect to a head traveling direction and a recording region 1 of video data is independent from the recording region 2 of the recording data and records the data important for reproducing the outline of the videos in the recording region 2 by arranging the head on the head scanning terminal side. In carrying out the pre-read edition, the preceding playback head 4 reproduces a portion of the voice data and the video data, reproduces and displays the outline of the images by the reproduced video data, inputs the voice signals from outside to the displayed videos by matching timing, mixes the same with the reproduced voice data and records the same again to the original place by a recording head 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus for recording and editing video data and audio data on a magnetic tape in a helical scan system, and more particularly, to editing recorded audio data while reproducing the audio data with one apparatus. About what is suitable to do.

[0002]

2. Description of the Related Art Some digital VTRs for broadcasting have a function of editing a magnetic tape on which video data and audio data are recorded in real time while reproducing the tape with one VTR. For example, a pre-read editing function that mixes already recorded audio data with another audio data while playing back the tape and records it again at the original location is one such editing function.

Hereinafter, a conventional broadcasting digital VTR having such a pre-read editing function will be described with reference to the drawings. FIG. 8 shows a conventional digital VT for broadcasting.
FIG. 3 is a schematic diagram showing a head arrangement on a rotating cylinder of R;
FIG. 3 is a view of the rotary cylinder 19 as viewed from above. In FIG. 8, the rotary cylinder 19 rotates counterclockwise. The rotary cylinder 19 is equipped with recording heads 3a, 3b and heads 4a, 4b for preceding reproduction. Rotating cylinder 1
At 9, the magnetic tape 5 runs obliquely over a section of about a half circumference (180 degrees).

FIG. 9 is a diagram showing a positional relationship between a recording track pattern on a magnetic tape 5 and a head. In FIG. 9, video data and audio data are already recorded on the magnetic tape 5, and tracks are formed diagonally. Here, the magnetic tape 5 always runs from right to left in the drawing at a constant speed. Therefore, signals are recorded on the track in order from right to left. The preceding reproduction head 4a
Leads the recording head 3a by the time required for signal processing at the time of recording and reproduction (the signal temporally later is recorded).
Mounted on a cylinder to play tracks. That is, for the track scanned by the recording head 3a, the preceding reproduction head 4a has N tracks (N is a natural number).
On the preceding track. Although not shown, when the recording head 3b is positioned on the tape, the preceding reproduction head 4b reproduces a track preceding the recording head 3b by N tracks.

Next, a description will be given of the configuration of the conventional broadcasting digital VTR and the operation in the case where audio data already recorded and another audio data are mixed and recorded again at the original location. FIG. 10 shows a configuration for editing audio data already recorded by a conventional broadcast digital VTR. The signal reproduced by the preceding reproduction head 4a or the reproduction head 4b is supplied to the reproduction processing circuit 13 via the head switch 21. The head switch 21 is controlled by a control signal synchronized with the rotation of the rotary cylinder 19, and selects the preceding reproduction head located on the magnetic tape 5. The reproduction processing circuit 13 performs demodulation, error correction processing and deshuffling processing on the reproduction signal selected by the head switch 21 and outputs a signal restored to the original digitized video data and audio data. The reproduced audio data is supplied to the mixing circuit 1
8 to obtain new audio data by mixing with externally input audio data via the audio input terminal 17.
Output to the recording signal processing circuit 12. The recording processing circuit 12 performs shuffling processing, error correction coding, modulation, and the like, and is supplied to the recording head 3a or 3b via the head switch 20, and overwrites all or part of the tracks on the magnetic tape. The head switch 20 is controlled by a control signal synchronized with the rotation of the rotary cylinder 19, and selects a recording head located on the tape.

The processing time required for signal processing until such a signal recorded on the tape is reproduced by the preceding reproducing head, mixed with another input data, and recorded on the tape again is N lines. This corresponds to the time required to scan a track. Further, as described above, the preceding reproduction head 4
a and 4b lead the recording heads 3a and 3b by N tracks respectively (the signals earlier in time were recorded).
It is configured to play tracks. by this,
The signal reproduced by the preceding reproduction head can be recorded at the original position on the magnetic tape after the reproduction, mixing and recording processes.

As described above, the conventional digital VT for broadcasting
In the R, by mounting a recording head and a preceding reproduction head on a cylinder so that a track temporally ahead of the recording head can be reproduced, data recorded while reproducing a tape and externally input data are input. An editing function of mixing the data with the original data and recording the original data again is realized.

[0008]

However, in the recording / reproducing apparatus of the helical scan type, recording / reproducing is performed by winding a tape obliquely around a rotary cylinder.
If the leading distance of the preceding reproducing head to the recording head is too large, the preceding reproducing head cannot scan the entire track. Such a limit of the preceding distance is physically determined by the configuration of the cylinder and the head, the tape width, and the like. Therefore, when the size of the rotating cylinder is reduced to reduce the size and weight of the device, or when the number of tracks per time required for recording and reproduction is increased by increasing the recording rate,
There is a problem that it is impossible to mechanically provide a preceding reproduction head at a position where the entire track can be reproduced, and pre-read editing cannot be realized.

An object of the present invention is to provide a recording / reproducing apparatus having a pre-read editing function for processing already-recorded audio data and recording it again at its original location even when the entire track cannot be reproduced by the preceding reproducing head. To provide.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a method of recording video data and audio data on a magnetic tape by a helical scan method. The recording area for video data is recorded in an area independent of the recording area for audio data, and the outline of image data to be recorded is reproduced in the recording area for video data. Important data is arranged and recorded on the end side in the head scanning direction.

The preceding reproducing means reproduces at least the number of tracks corresponding to the time required for the reproduction signal processing and the recording signal processing with respect to the track scanned by the recording head, and the video output means is the preceding reproducing means. By reproducing the outline of the reproduced video data, the recording processing means overwrites only the audio data on the recording track.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first invention of the present invention is a recording method for recording video data and audio data on a magnetic tape by a helical scan method, wherein the audio data is recorded on a recording track in a head scanning direction. On the other hand, it is arranged and recorded in an area near the terminal end, the recording area of the video data is an area independent of the recording area of the audio data, and in the recording area of the video data, the outline of the video data to be recorded is described. A recording method characterized by arranging and recording data important for reproduction at the end side in the head scanning direction, wherein an audio recording area is provided at the end side of head scanning which is a reproducible range on a track. With this arrangement, the outline of the audio data and the video data can be reproduced in advance.

According to a second aspect of the present invention, in the first aspect, data important for reproducing the outline of the video data is pixel data near the center of the screen or data of a low-frequency component of the video data. By recording the low-frequency component at the center of the screen at the end of the head scan in the video recording area, an overview of the video data is reproduced at the time of preceding reproduction, and the timing of the video is adjusted. In addition, it is possible to easily input voice from outside.

According to a third aspect of the present invention, in the first aspect, one frame of the video data is divided into a plurality of segments in the horizontal direction, and the end of the video data recording area in the head scanning direction is provided. From the segment close to the center of the screen, the recording method characterized by arranging and recording at least the low-frequency component of the video data of each segment in the case where the data can be reproduced only halfway in the recording area of each segment. Also, the adjacent area on the screen can always be reproduced.

According to a fourth aspect of the present invention, there is provided the recording / reproducing apparatus according to the first aspect, wherein the video data and the audio data are recorded on a magnetic tape by a helical scan method. The recording area of the video data is arranged in an area independent from the recording area of the audio data, and the recording area of the audio data is arranged in an area close to the terminal end in the scanning direction. For the magnetic tape on which data important for reproduction is arranged and recorded on the end side in the head scanning direction, a recording head, and at least reproduction signal processing and recording signals for a track scanned by the recording head. Preceding playback means for playing back tracks preceding by a number of tracks corresponding to the time required for processing, and video data reproduced by the preceding playback means. A recording / reproducing apparatus comprising: video output means for reproducing and outputting an outline; and recording processing means for overwriting only audio data on the recording track, wherein the audio data is reproduced in advance and another It becomes physically possible to mix and record the signal.

FIG. 1 is a diagram showing a positional relationship between a recording track pattern and a head according to an embodiment of the present invention.

In FIG. 1, 1 is an audio data recording area for recording audio data, 2 is a video data recording area for recording video data, and 3 is a magnetic tape 5 for recording video and audio data.
The recording head 4 records the video and audio data from the magnetic tape 5 in advance.

As shown in FIG. 1, the area closest to the end in the head scanning direction on the recording track of the magnetic tape 5 is the audio data recording area 1, and the area independent of the audio data recording area is the video data recording area. Is recorded as recording area 2.

FIG. 2 is a block diagram of a recording apparatus for recording with the track pattern of FIG. In FIG. 2, FIG.
The same reference numerals are given to the same components as those described above, and the description is omitted.

In FIG. 2, reference numeral 6 denotes a video signal input terminal to which video data is input, 7 denotes an audio signal input terminal to which audio data is input, and 8 denotes a video which compresses video data input from the video signal input terminal 6. A compression circuit, 9 is an audio shuffling circuit for rearranging audio data input from the audio signal input terminal 7 in a predetermined order, 10 is a memory for storing video data compressed by the video compression circuit 8, and 11 is a video compression circuit. A video data rearranging circuit 12 for rearranging the video data compressed by 8; and 12 a magnetic tape for recording the compressed video data output from the video data rearranging circuit 11 and the audio data output from the audio shuffling circuit 9 by the recording head 3. 5 is a recording processing circuit.

In the present embodiment, it is assumed that video data is compressed by the DV compression method used in a home digital VTR.

In FIG. 2, digital video data is input to a video compression circuit 8 via a video input terminal 6. The video compression circuit 8 performs a compression process on video data according to the DV compression method and outputs the result. FIG. 3 shows the number of scanning lines in one frame 5
25 lines, 525/60 with a field frequency of 60 Hz
FIG. 3 is a diagram showing a video shuffling rule of a DV compression method in the system.

As shown in FIG. 3, the screen of one frame is divided into 10 rows in the vertical direction and 5 columns in the horizontal direction, and each super block is composed of 27 macro blocks. In the DV compression method, one superblock is selected from each different row of each column, one macroblock is taken out from each superblock to form one video segment, and DCT, quantization, and variable length are performed in video segment units. A compression process such as encoding is performed. At this time, the data amount is always controlled to be equal to or less than a predetermined amount, and the data after compression for the video signal of each video segment is a DIF composed of five DIF blocks.
Store in group. One DI for each macroblock
F blocks are allocated and stored from the low band data of the macro block. Data that could not be stored
The data is stored in the free area of the other four DIF blocks in the DIF group. That is, the low-frequency data of each macroblock is stored in the DIF block, and the high-frequency data is also stored at least in the DIF group. A similar compression process is performed on 27 video segments in a super block to form one sector. That is, one sector is constituted by 27 × 5 = 135 DIF blocks. For the j-th DIF block of the k-th DIF group in the sector, k (k = 0 to k)
26) corresponds to the macroblock number in the super block, and j (j = 0 to 4) corresponds to five columns on the screen. 1
When the processing of the sector is completed, the next five super blocks are selected and the same processing is performed. One frame of video data is compressed, stored in 10 sectors, and output as a compressed data stream.

The video data rearranging circuit 11 converts the input compressed data stream into a DI within each sector.
A rearrangement process is performed for each F block. The video data rearranging circuit 11 writes 135 DIF blocks in the sector into the memory 10 in the order of input, and reads out all 27 DIF blocks with j = 2 at the time of reading, and then j = 1, j = The data of the DIF block is read in the order of 3, j = 0, j = 4. That is, the data is read from the DIF block near the center of the screen. At this time, j =
K = 0, 1, 2,..., 26 when 2, j = 3 and j = 4
, And when j = 0 and j = 1, conversely k = 26, 25, 24,..., 0. The audio shuffling circuit 9 rearranges audio data input from the audio signal input terminal 7 in a predetermined order. The recording signal processing circuit 12 adds an error correction code to the compressed video data and the shuffled audio data, performs modulation processing, and records the data on the magnetic tape 5. A sync block, which is a unit of recording, corresponds to a DIF block, and data of one sector is recorded on one track. The data format on the tape is as shown in FIG. 1, and the audio data is located on the recording track at the end end in the head scanning direction.

FIG. 4 is a diagram showing the data arrangement within one track. 4, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIG. 4, in the recording area of the video data, from the end side of the head scan, j = 2, j = 1, j = 3, j = 0, and j = 4. A low-frequency component of the video data of each super block is recorded, and a parity is recorded at the end. In the recording area of j = 2, j = 3, j = 4, data is recorded in the order of k = 0, 1,..., 26, that is, from left to right on the screen. In the recording area, data is recorded in the order of k = 26, 25,..., 0, that is, from right to left on the screen.

Next, a case where pre-read editing is performed on a tape recorded as described above will be described.

FIG. 5 is a block diagram of a recording / reproducing apparatus according to an embodiment of the present invention. 5, the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 5, reference numeral 14 denotes a video decompression circuit which is a video output means for decompressing the compressed video data reproduced by the reproduction processing circuit 13, and 15 converts the audio data reproduced by the reproduction processing circuit 13 into original data. An audio deshuffling circuit, 16 is a video signal output terminal for outputting video data output from the video decompression circuit 14, 17 is an audio signal input terminal for inputting audio data, and 18 is audio data and audio output from the audio deshuffling circuit 15. This is a mixing circuit that mixes audio data input from the signal input terminal 17.

Here, it is assumed that each of the recording processing and the reproduction processing requires a processing time of two frames. Accordingly, the preceding reproducing head 4 is mounted on the rotating cylinder so as to scan the track 4 frames, that is, the track 40 tracks before the recording head 3. The scanning of each head on the tape is as shown in FIG. 1, where N = 40
It is. As shown in FIG. 1, only a part of the track is wrapped around the cylinder at the position where the preceding reproduction head 4 scans on the tape, so that a part of the audio data and the video data is reproduced. The data reproduced by the reproduction processing circuit 13 is subjected to reproduction processing such as demodulation and error correction processing, and is separated into video data and audio data. The audio data is converted by the audio deshuffling circuit 15 and output. The video data is input to the video expansion circuit 14,
The decoding process, the inverse quantization, and the inverse DCT process of the variable length code are performed for each reproduced macro block. At this time, if all the data of the macro block is not stored in the reproduced sync block, the video signal is reproduced and output only from the stored low-frequency data. While watching the output video, audio data such as narration and music is generated in synchronization with the video, and input from the audio signal input terminal 17. The mixing circuit 18 mixes and outputs the audio data input from the audio signal input terminal 17 and the audio data output from the audio deshuffling circuit 15. The data output from the mixing circuit 18 is output to the audio shuffling circuit 9.
, After a predetermined shuffling process, the recording processing circuit 1
2 performs a recording process and overwrites the original audio data recording area.

Here, for example, when about 70% of the video recording area shown in the pre-reproducible range in FIG. 4 is reproduced, the pre-reproducible area is displayed on the screen as a shaded area in FIG. , And the center of the screen can be reproduced with at least a low-frequency component. The subject of the video is often located in the center of the screen, and if there is a low-frequency component in frequency, an outline of the image can be reproduced. Therefore, it is possible to grasp the outline of the image even if the entire screen cannot be reproduced.

As described above, even when the entire track cannot be reproduced by the preceding reproducing head, the audio data is reproduced in advance by providing the audio recording area at the end of the head scanning which is the reproducible range on the track. It becomes physically possible to mix and record with another signal. In addition, by recording the low-frequency component at the center of the screen at the end of the head scan in the video recording area, it is easy to reproduce the outline of the video data at the time of preceding playback, and to input audio from the outside in synchronization with the video. Can be.

Further, by dividing the data in the horizontal direction on the screen (5 segments in the present embodiment) and arranging and recording data in segment units, the compatibility with the DV compression shuffling method is good. When applied to a digital VTR adopting the DV compression method, it can be realized by adding a simple rearrangement circuit.

At this time, the data arrangement in units of macro blocks in each segment is arranged in the order from right to left with respect to the screen, with the segment located to the left of the center on the screen, and reversed for the segment located at the right of the center. Are arranged in order from left to right in order from the macroblock adjacent to the adjacent segment on the screen center side. Accordingly, even when the data can be reproduced only halfway in the recording area of each segment, the adjacent area on the screen can always be reproduced.

In the present embodiment, a case has been described where the video compression method is the DV compression method and one screen is divided in units of super blocks according to the DV compression shuffling method. However, the compression method and the shuffling method are the same. The present invention is not limited to this, and can be applied in various methods. When recording is performed by shuffling more randomly, for example, an area in which preceding reproduction is possible is as shown in FIG. At this time, only a rectangular area (reproduced data display area) inscribed in the reproducible area is displayed, and other areas are displayed at a fixed level (fixed data) such as a black level, so that a more easily viewable image is displayed. can get.

It is needless to say that the video data is not limited to the 525/60 format, but is also effective when recording video signals having different signal formats. For example, the same recording method and recording / reproducing apparatus can be used when rearranging the pixels at the upper and lower edges of the screen to the left and right edges of the screen, or when inputting and recording an image obtained by subsampling and dividing the screen horizontally and vertically. realizable.

[0036]

As described above, according to the present invention, even when the entire track cannot be reproduced by the preceding reproducing head due to signal processing delay or mechanical limitation, already recorded audio data is processed and restored to the original. And a recording / reproducing apparatus having a pre-read editing function of recording data at the location of the recording medium.

[Brief description of the drawings]

FIG. 1 is a diagram showing a positional relationship between a recording track pattern on a magnetic tape and a head according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a recording apparatus according to an embodiment of the present invention.

FIG. 3 is a diagram showing a shuffling rule of the DV compression method.

FIG. 4 is a diagram showing a data arrangement on a recording track according to the embodiment of the present invention;

FIG. 5 is a block diagram illustrating a configuration of a recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 6 is a diagram showing a first reproduced video example at the time of pre-read editing in the embodiment of the present invention.

FIG. 7 is a diagram showing a second reproduced video example at the time of pre-read editing according to the embodiment of the present invention.

FIG. 8 is a diagram showing a head arrangement on a rotary cylinder of a conventional recording / reproducing apparatus.

FIG. 9 is a diagram showing a positional relationship between a recording track on a magnetic tape and a head in a conventional recording / reproducing apparatus.

FIG. 10 is a block diagram showing a configuration of a conventional recording / reproducing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Video data recording area 2 Audio data recording area 3 Recording head 4 Advance reproduction head 5 Magnetic tape 8 Video compression circuit 9 Audio shuffling circuit 11 Video data rearrangement circuit 12 Recording processing circuit 13 Reproduction processing circuit 14 Video expansion circuit 15 Audio deshuffling Circuit 18 Mixing circuit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C018 BA02 BA06 5D044 AB05 AB07 BC01 CC03 DE02 DE03 GK07 HL14 5D110 CA02 CA05 CA06 CB01 CB06 CG04

Claims (6)

[Claims] 1. A recording method for recording video data and audio data on a magnetic tape by a helical scan method,
The audio data is recorded on a recording track in an area near the end in the head scanning direction, and the recording area for the video data is an area independent of the recording area for the audio data. A recording method comprising: arranging and recording data important for reproducing an outline of video data to be recorded in an end area in the head scanning direction in an area. 2. The data important for reproducing the outline of the video data is pixel data near the center of the screen or low-frequency component data of the video data.
The recording method described. 3. The video data of one frame is divided into a plurality of segments in a horizontal direction, and in the recording area of the video data, each of the segments is sequentially arranged from the end side in the head scanning direction from the segment near the center of the screen. 3. The recording method according to claim 2, wherein at least a low-frequency component of the video data is recorded. 4. A segment is divided into a plurality of pixel blocks, and in a region where each of the segments is arranged in a recording region of video data, an adjacent portion on the screen center side within the segment from the end side in the head scanning direction. 4. The recording method according to claim 3, wherein data is arranged and recorded in order from the pixel block at a boundary portion that is in contact with a segment. 5. A recording / reproducing apparatus for recording video data and audio data on a magnetic tape by a helical scan method, wherein the audio data is arranged on a recording track in an area near an end in a head scanning direction. The recording area of the video data is an area independent of the recording area of the audio data,
In the recording area of the video data, for the magnetic tape recorded by arranging data important for reproducing the outline of the video data to be recorded on the end side in the head scanning direction, a recording head, A pre-reproduction unit that reproduces at least the number of tracks corresponding to the time required for the reproduction signal processing and the recording signal processing with respect to the track scanned by the recording head; and video data reproduced by the pre-reproduction unit. A video output means for reproducing and outputting an outline of the above, and a recording processing means for overwriting only audio data on the recording track. 6. The recording / reproducing apparatus according to claim 5, wherein the video output means replaces the area outside the rectangular area inscribed in the area on the screen which can be displayed with the video data reproduced by the preceding reproduction means, with fixed data. apparatus.