JP2001195840A - Method for recording data, edition method, edition device and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit the connection of adequate MPEG streams and to permit seamless reproduction (continuous reproduction which is not accompanied by temporary stop by underflow of a buffer and a frame skip). SOLUTION: A current EP detector 24 supplies a trigger signal to a main data recording and reproducing device 22 upon detection of the current EP which is boundary information to indicate whether the tops or terminals of N pieces of the edition minimum units of compressed encoding data at every ECC interleave flocks. When the main data recording and reproducing device 22 receives the trigger signal described above, the device records the compressed encoding data inputted from outside through a terminal 21 from the arbitrary edition point of the already recorded recording medium. The edition point is the track which is the top of the boundary information with which the current EP is detected. The track is the boundary of an ECC interleave which is the beginning of a closed GOP and therefore the seamless connection is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a data recording method,
The present invention relates to an editing method, an editing apparatus, and a recording medium. In particular, a block unit that can be edited is specified, and video and audio data within the minimum editing unit can be seamlessly reproduced even after editing. The present invention relates to an editing device and a recording medium.

[0002]

2. Description of the Related Art Today, digital technology is actively used in computers, broadcast media, communication media, and storage media. The most important role in these information infrastructures is MPEG (Moving Pic)
Nature Experts Group), which will be briefly described. MPEG was established in 1988 by the ISO / IEC JTC
1 / SC2 (International Organization for Standardization / International Electrotechnical Commission / Technical Committee 1 / Subcommittee 2, current SC29) This is the abbreviation of the name of the organization that considers the moving picture coding standard.

[0003] MPEG has MPEG1, MPEG2 and other standards. MPEG1 (MPEG phase 1)
Is a standard for storage media of about 1.5 Mbps. It uses JPEG for the purpose of still image coding and video compression for low transfer rates of video conferencing and video telephony of Integrated Services Digital Network (ISDN). The target H. 26
1 (CCITT SGXV, current ITU-T SG1
5 standardized) and introduced a new technology for storage media. These are 199
It was enacted as ISO / IEC 11172 in August 3rd. MPEG2 (MPEG Phase 2) is an ISO / I / O in November 1994, aimed at a general-purpose standard so as to support various applications such as communication and broadcasting.
EC 13818, H.E. 262.

[0004] The encoding part of MPEG is created by combining several techniques. FIG. 9 is a block diagram showing an example of an image compression / encoding device using MPEG. In the figure, an input image is decoded by a motion compensation predictor 1 and a difference between the motion compensated prediction image and the input image is calculated by a subtraction circuit 2 to reduce a time redundant portion. There are three modes of prediction from the past, the future, and both. These are 16
It can be switched and used for each MB (macroblock) of 16 pixels. The prediction direction is determined by the picture type given to the input image. Picture types include a P picture, a B picture, and an I picture. P-pictures have two modes of prediction from the past and independent encoding of the MB without prediction. B-pictures have four modes for prediction from the future, prediction from the past, prediction from both, and independent encoding. It is an I picture that all MBs are independently encoded.

[0005] Motion Compensation (MC)
Predicts a motion vector with half-pel accuracy by performing pattern matching on a motion area for each MB, and shifts the motion vector by an amount corresponding to the motion for prediction. The motion vector has a horizontal direction and a vertical direction, and is transmitted as additional information of the MB together with the MC mode indicating where to predict the motion vector. GOP (Group Of) from the I picture to the picture before the next I picture
Picture), when used in storage media or the like, generally about 15 pictures are used.

[0006] The difference image signal extracted from the subtraction circuit 2 is subjected to orthogonal transform in a DCT unit 3. Discrete Cosine Transform (DCT) is an orthogonal transform that discretely transforms an integral transform using a cosine function as an integral kernel into a finite space. In MPEG, two-dimensional DCT is performed on an 8-by-8 DCT block obtained by dividing an MB into four. In general, since a video signal has many low-frequency components and few high-frequency components, when DCT is performed, coefficients concentrate on low frequencies.

[0007] DCT image data (DCT coefficient)
Are quantized by the quantizer 4. In this quantization, a value obtained by multiplying a value obtained by weighting a two-dimensional frequency of 8 × 8 called a quantization matrix by a visual characteristic by a value called a quantization scale for multiplying the whole by a scalar is used as a quantization value.
Divide the T coefficient by its quantized value. When inverse quantization is performed by the decoder, the original DCT is obtained by multiplying by the quantization value.
You will get a value that is close to the coefficient.

[0008] The quantized data is variable-length coded by a VLC unit 5. A direct current (DC) component of the quantized value is a DPCM (Differential Pull
se Code Modulation). In addition, Huffman coding in which an alternating current (AC) component performs a zigzag scan from a low frequency band to a high frequency band, assigns a run length of zero and an effective coefficient value to one event, and assigns a code having a short code length to a code having a high occurrence probability. Is performed. The variable-length coded data is stored in a temporary buffer 6 and output as coded data at a predetermined transfer rate.

The generated code amount of the output data for each macroblock is supplied to a code amount controller 7 and the error code amount between the generated code amount and the target code amount is fed back to the quantizer 4. The code amount is controlled by adjusting the quantization scale. The quantized image data is inversely quantized by an inverse quantizer 8, inversely DCTed by an inverse DCT 9, temporarily stored in an image memory 11 through an adder circuit 10, and then temporarily stored in a motion compensation predictor 1. , Is used as a reference decoded image for calculating a difference image. The output signal of the motion compensation predictor 1 is input to a subtraction circuit 2 and an addition circuit 10.

The coded bit stream output from the buffer 6 has a variable length code amount for each picture in the case of video. This is because MPEG uses information transformation such as DCT, quantization, and Huffman coding, and at the same time, it is necessary to adaptively change the code amount allocated to each picture in order to improve image quality. This is because since the motion compensation prediction is performed, the entropy of the coded image itself greatly changes, for example, in some cases, the input image is coded as it is, and in some cases, the difference image which is the difference between the predicted images is coded.

In this case, in most cases, the code amount is controlled while allocating to the entropy ratio of the image and keeping the buffer limit. The limitation of this buffer is that encoding is performed so that the buffer on the decoding device side does not cause overflow or underflow. VBV (Video)
Buffering Verifier). Details on this are provided by the International Organization for Standardization (ISO).
11172-2 and ISO13818-2. If this rule is adhered to, the rate in the VBV buffer changes locally, but if the observation time is lengthened, the transfer rate becomes fixed, and MPEG defines this as the fixed transfer rate.

FIG. 10 is a block diagram showing an example of an apparatus for decoding encoded data compressed and encoded by MPEG.
In the figure, encoded data compressed and encoded by MPEG is variable-length decoded by a VLD unit 15 and then multiplied by a quantization width by an inverse quantizer 16 to obtain the original DC data.
After the value is approximated to the T coefficient, it is supplied to the inverse DCT unit 17 and subjected to inverse DCT to be locally decoded.

The motion vector and the prediction mode extracted from the inverse quantizer 16 are supplied to the motion compensation predictor 18 together with the decoded data from the image memory 20, and the motion compensated and predicted image data is output therefrom. Let it. The adder 19 receives the data from the inverse DCT unit 17 and the motion compensation predictor 1
8 to decode the image data equivalent to the image data input to the encoding device by adding the motion compensated image data from
0 and output to the outside.

In such an MPEG system, variable-length coded data is transferred at a fixed transfer rate (coding rate).
In the case of encoding by using the upper limit of the buffer amount of the decoder as shown in FIG. 11, data is input at a constant speed, and after a predetermined value is accumulated, a predetermined time unit (NTS
A virtual decoder model that performs instantaneous decoding in the case of a C-system video signal (in units of 1 / 29.97 seconds) is connected to the output of the encoder and used so that the buffer does not cause overflow or underflow. MP to encode
Specified by EG.

In FIG. 11, I, P and B are MPEG
It shows prescribed I pictures (intra-frame coded pictures), P pictures (inter-frame forward coded pictures), and B pictures (bidirectional coded pictures), which are stored in a buffer to decode each picture. This is performed instantaneously in units of 1 / 29.97 seconds, and data is shown to be instantaneously extracted from the buffer. In the case of the fixed transfer rate, in the steady state, the code amount changes as shown in FIG. In the case of a variable transfer rate, the definition of the fixed transfer rate described above is extended so that when the buffer occupancy value reaches the upper limit value, the reading of the decoder is stopped so that overflow does not occur in principle. Have been.

In the MPEG system described above,
There has conventionally been a request to edit and record compression-encoded data relating to other information on a recording medium on which data relating to desired information which has been compression-encoded by the MPEG system is recorded in a predetermined format. Conventionally, it has been proposed to easily realize high-speed and accurate cueing, high-quality special reproduction, editing, and the like even for rewritten data.
There is a method described in JP-A-213566.

In the conventional method described in this publication, in a recording data block to which an error correction code is added in ECC block units, a control ECC block is used in addition to a data ECC block.
Main data group number to set and record blocks,
The sector number at which the main data group starts, data indicating the number of the sub data ECC block in which the sub data synchronized with the main data group is located, and the number of the sub data in the sub data ECC block. Data indicating whether the data exists in the sub data block is arranged in the control ECC block.

In the proposed conventional method, data blocks at different positions are inserted at the time of editing and recording. Therefore, the ECC block number in which the sub data of the insertion source exists and the sub data of the insertion source are stored in the ECC block for the data. Editing is possible by arranging.

In addition, at each recording from the start to the end of recording, the remaining portion of the last ECC block where no data is recorded is filled with meaningless data, and additional recording is performed. At the same time, a method has been proposed in which recording is started from the beginning of the next ECC block.

Also, Japanese Patent Application Laid-Open No. 8-335388 has an object to provide a video data recording apparatus for recording video data for each GOP so that non-tracking reproduction can be performed at high speed in a reverse direction. , GOP
A data arranging means for arranging video data for each GOP in a predetermined area of a plurality of data blocks of a predetermined format; an identification code generating means for generating, for each GOP, at least an identification code for identifying the GOP; GOP
Identification code assigning means for assigning an identification code for the generated GOP to a predetermined area of each of a plurality of data blocks in which the video data is arranged; and for each GOP, the identification code for identifying the GOP; The GO
Identification code data generating means for generating identification code data having the identification code for identifying a GOP connected to P as data; and a plurality of data blocks in which the video data for each GOP are arranged and the identification code data. There has been proposed a video data recording apparatus having recording means for recording on a recording medium in the order of GOPs for each GOP.

[0021]

However, according to the conventional method described in Japanese Patent Application Laid-Open No. H11-213566,
Although it is possible to record data in a predetermined ECC block, it is not possible to indicate an editable boundary in the data. In addition, the above-mentioned Japanese Patent Application Laid-Open No. Hei 8-3
Japanese Patent No. 35388 has a means for arranging an MPEG GOP in a predetermined data block.
The OP could not indicate whether it was encoded in an editable state.

Therefore, if editing is performed by the conventional method described in each of the above publications, an appropriate MPEG stream cannot be connected, and seamless playback (pause due to buffer underflow or closed GOP does not occur) Continuous playback without frame skipping) was not possible.

The present invention has been made in view of the above points, and has as its object to provide a data recording method, an editing method, an editing apparatus, and a recording medium capable of performing editing capable of seamlessly reproducing video and audio. And

It is another object of the present invention to provide a data recording method, an editing method, an editing apparatus, and a recording medium that enable smooth connection of audio data near an editing point.

[0025]

In order to achieve the above object, a data recording method according to the present invention is directed to a method for recording compressed encoded data in an ECC interleaved block in a predetermined unit and recording the data on a recording medium. A recording method, wherein a minimum unit of editing of compression-encoded data is configured to fit in N ECC interleaved blocks, and is a head or end of N minimum units of editing of compressed-encoded data for each ECC interleaved block. It is characterized in that boundary information indicating whether or not the information is recorded.

According to the present invention, the boundary information indicating whether it is the start or end of the N minimum editing units of the compressed and coded data is recorded for each ECC interleaved block, so that the editing is performed based on the boundary information. It is possible to perform editing for connecting compression-encoded data of different information at the head of the minimum unit.

Further, the data recording method of the present invention is characterized in that in addition to the above-mentioned boundary information, boundary existence information indicating whether or not the boundary information exists after a predetermined time is recorded. According to the present invention, when it is detected based on the boundary existence information that the boundary information is present after a predetermined time, editing in which the level of the information signal changes smoothly near the head of the minimum unit of editing can be performed.

Further, the editing method and the editing apparatus according to the present invention
In order to achieve the above object, the minimum unit of editing of compressed encoded data is configured to fit into N ECC interleaved blocks, and the beginning or end of the N minimum editing units of compressed encoded data is set for each ECC interleaved block. An editing method or an editing apparatus for editing and recording new compressed and encoded data relating to arbitrary information on a recorded recording medium on which boundary information indicating whether or not the recorded recording medium has been recorded. The recording of new compression-coded data is performed after waiting for detection of boundary information indicating the start or end of the minimum unit of editing from the reproduction signal of.

According to the present invention, new compressed encoded data is recorded after detecting the boundary information indicating the start or end of the N minimum editing units of the compressed encoded data for each ECC interleaved block. With this configuration, it is possible to perform editing for connecting compression-encoded data of different information at the head of the minimum editing unit based on the above boundary information.

Further, the editing method and the editing apparatus according to the present invention
In order to achieve the above object, the minimum unit of editing of compressed encoded data is configured to fit into N ECC interleaved blocks, and the beginning or end of the N minimum editing units of compressed encoded data is set for each ECC interleaved block. New compressed coded data relating to arbitrary information on a recorded recording medium on which boundary information indicating whether or not the boundary information exists and boundary existence information indicating whether the boundary information exists after a predetermined time are recorded. A method or apparatus for editing and recording, when detecting boundary existence information indicating that boundary information exists after a predetermined time from a reproduction signal of a recorded recording medium, a compression code relating to audio information in the reproduction signal. After the fade-out or mix-fade of the coded data within a predetermined time, the fade-in or audio connection And performing.

Further, in order to achieve the above object, the recording medium of the present invention has a structure in which the compression-encoded data is converted into ECC data in a predetermined unit.
A recording medium in which an interleaved block is formed and recorded in a predetermined format together with control information, wherein the minimum unit of editing of the compression-encoded data is configured to fit into N ECC interleaved blocks. Boundary information indicating whether it is the beginning or end of the N minimum editing units of the compression-encoded data is recorded as a part of the control information.

Further, in order to achieve the above object, the recording medium of the present invention is configured such that the minimum unit for editing the compressed coded data is contained in N ECC interleaved blocks. , Boundary information indicating whether or not the N pieces of editing minimum units are at the beginning or end, and boundary existence information indicating whether the boundary information exists after a predetermined time, are recorded as a part of the control information. It is characterized by.

Here, the minimum unit of editing of the compression-encoded data is one or a plurality of GOPs composed of video data and audio data for a plurality of frames that are compression-encoded by the MPEG method. The first GOP is
It is characterized by being constituted by a closed GOP.
In the present invention, the editing minimum unit of the compression-encoded data is one or more GOPs composed of video data and audio data for a plurality of frames that are compression-encoded by the MPEG method. First GOP
Is composed of a closed GOP, and the occupancy value of the VBV buffer, which is defined so that the buffer on the decoding device side does not generate overflow or underflow, is encoded with a fixed transfer rate. If the transfer rate is higher, the coding is started from a predetermined first value, and the coding is completed at a predetermined first value. If the transfer rate is a variable transfer rate, the coding is started from a predetermined second value. , The encoding is terminated with a value larger than the second value. As a result, it is possible to connect the compression-encoded data without causing overflow or underflow.

[0034]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of one embodiment of a data editing device according to the present invention, and FIG. 2 is a block diagram of another embodiment of the data editing device according to the present invention.
The embodiment of FIG. 1 can be applied to both the video information and the audio information or the video information among the compressed and coded data related to the video information and the audio information. The embodiment of FIG. The coded data is applied to compressed coded data of audio information. In the embodiment shown in FIG. 1, MPEG input from the outside via a terminal 21
The main data recording / reproducing unit 22 edits and records the compression-encoded data of the video information and the audio information compressed by the method from an arbitrary editing point of the recording medium which has been recorded in a predetermined format to which various types of control information are added.

In the present invention, the form of the recording medium is not limited, but a magnetic tape based on the D-VHS (registered trademark) system will be described as an example of the recording medium. The main data recording / reproducing device 22 is a recording / reproducing device used in the D-VHS system. For example, the main data recording / reproducing device 22 is provided with two sets of double azimuth heads having 180 degrees opposite to each other and having different azimuth angles. A helical scan type magnetic recording / reproducing apparatus configured to record / reproduce a digital signal composed of compression-encoded data and control information on a magnetic tape running at a constant speed while being wound obliquely over an angle range of about 180 degrees on the side surface ( VTR).

Each of the sets of double azimuth heads includes a first rotary head having a first azimuth angle and a second rotary head having a second azimuth angle.
Is a pair head in which a second rotating head having an azimuth angle of is arranged in close proximity, and simultaneously records and forms two tracks having different azimuth angles in parallel by one scan. Each track is configured by arranging a plurality of fixed-area data areas called sync blocks corresponding to data blocks in accordance with scanning by a rotary head.

The above-mentioned digital signal, like a conventional digital VTR having a pair head rotating at 30 rps, has 24 tracks in the case of the NTSC system among the NTSC system and the PAL system which are different in the number of frames per second. Record at a rate of 6 frames, while
In the case of the PAL system, recording is performed at a rate of 5 frames on 24 tracks, that is, both the NTSC system digital signal and the PAL system digital signal are recorded with the same data amount in a 24 track cycle. Control the code amount.

In addition to this, the interleave of the error correction code (ECC) is generated so that both tracks of the NTSC system and the PAL system can be completed in six tracks at the time of digital signal recording. That is, in this D-VHS system, an ECC interleaved block is configured in units of 6 tracks.

A track format to which this embodiment is applied will be described. On one track, a plurality of data blocks called sync blocks (SB) are time-sequentially combined to form a track format shown in FIG. The track format shown in FIG. 3 includes a margin area 31, a preamble area 32, a subcode area 33, a postamble area 34, an IBG area 35, a preamble area 36, a data area 37, an ECC code area 38, a postamble area 39, and a margin area. It consists of forty. Here, of the data area 37 and the ECC code area 38 constituting the main data area, the data area 3
Reference numeral 7 denotes an area where digital data is recorded in 306 sync blocks. The ECC code area 38 is an area where an outer code (C3 code) for error correction is recorded.
It consists of 0 sync blocks.

In this embodiment, since the ECC code is recorded so as to be completed in six tracks, the ECC code is subjected to data shuffling in 180 sync blocks, of which 30 (= 180 sync blocks / 6 tracks) ) Each sync block is the above EC of each track.
It is arranged and recorded in the C code area 38. The margin areas 31 and 40 each include two sync blocks, the preamble area 32, the postamble areas 34 and 39, the IBG area 35 and the preamble area 36 each include three sync blocks, and the subcode area 33 includes four sync blocks. In the track of the book, digital signals of 356 sync blocks are recorded in total.

Next, the configuration of the sync block will be described. As shown in FIG. 4, a sync block, which is a data block of the data area 37 and the ECC code area 38, has a 2-byte synchronization signal (Sync) area 41 for reproducing the sync block and 3-byte address information ( ID) area 42, a 99-byte data storage area 43 for storing various information such as video information and audio information, and an 8-byte parity (ECC code) area for error correction of the information of the sync block. 44 are combined in a time-series manner to form a total of 112 bytes.

As shown in FIG. 5, the format in the subcode area 33 is a 2-byte synchronization signal (Sy).
nc) area 51 and 3-byte address information (ID)
Areas 52 to 54, a 1-byte subcode header area 55, an 18-byte subcode data area 56,
A block of 28 bytes in total, consisting of a parity area 57 of bytes, is synthesized in time series. The subcode data in the subcode data area 56 includes information (for example, main data format information, recording contents, recording date and time, etc.) attached to the main data in the data area 37 following the subcode area 33 in FIG.

According to the present invention, in this subcode data, for each ECC interleaved block, boundary information indicating whether the start or end of N minimum editing units of the compression-encoded data and the boundary information are predetermined. Boundary presence information indicating whether or not it exists after a time is recorded. In the present embodiment, the boundary information indicating whether the start or end of the N minimum editing units of the compressed encoded data for each ECC interleaved block is N minimum editing units of the compressed encoded data for each ECC interleaved block. Will be described as indicating the beginning.

These information signals are, as shown in FIG.
It is recorded in the subcode data area 56 as a byte identification signal (ID) 61 and 5-byte edit point (Edit Point) data 62. As shown in FIG. 7, in the 5-byte edit point data 62, the first 1 byte records 8 bits as an identification signal (ID), the next 4 bits store the next EP information, and the next 4 bits. The current EP information is recorded in bits, and the remaining 4 bytes record 0 as a spare.

The next EP is an example of the boundary existence information indicating whether the boundary information exists in the next track, that is, whether the next track is the head of the boundary information. For example, when the 4-bit value is “0001”, the next track is the head of the boundary information and “0000”
Indicates that the next track is not the head of the boundary information. The current EP is an example of the boundary information indicating whether or not it is the head of the N minimum editing units of the compression-encoded data, that is, whether or not the current track is the head of the boundary information. For example, when the 4-bit value is “0001”, the current track is the head of the boundary information and “00”
"00" indicates that the current track is not the head of the boundary information.

As a specific unit example of the combination with the MPEG data, when the editing is designed to be performed in units of 0.6 seconds, the data of the MPEG GOP is composed of a plurality of ECC interleaved blocks, and the GOP is 18 bits. Assuming that the frame is composed of frames, one GOP data is recorded on 12 ECC interleaved blocks, that is, 72 (= 12 × 6) tracks, and when the data ends in the middle of the ECC interleaved block, the next ECC
Until interleaving, stuffing (invalid) data is recorded. The current EP in the edit point data is recorded as "0001" on the first track of the 12 ECC interleaved blocks, and the next EP in the edit point data is recorded as "0001" on the last track.

When the editing is designed to be performed in units of 2 seconds, if the data of the MPEG GOP is composed of a plurality of ECC interleaved blocks, and if the GOP is composed of 15 frames, 40 ECC interleaved blocks, That is, one GOP data is recorded on 240 (= 40 × 6) tracks, and when the data ends in the middle of the ECC interleave block, stuffing (invalid) data is recorded until the next ECC interleave. In the track of the first ECC interleaved block of the 40 ECC interleaved blocks, the current EP in the edit point is recorded as "0001", and in the last track, the next EP in the edit point is recorded as "0001".

Next, when editable boundary information is designated by using the edit point data information, M
An editable encoding method in PEG will be described with reference to FIG. FIG. 8A shows that the target code amount is limited so that the buffer value of the last picture of the first video data I in a predetermined picture unit becomes the first buffer value V1, and the first video data I 2 shows a state in which the buffer value of the first picture of the second video data II in a predetermined picture unit following the last picture is connected with the buffer value starting from the second buffer value V2.

If the two video data I and II thus encoded are encoded at a fixed transfer rate, the connection is made as shown in FIG. 8B. That is, the second video data II is calculated by subtracting the second buffer value V2 from the first buffer value V1.
As shown by II ', the whole is shifted upward and combined. For this reason, the buffer occupancy value of the second video data exceeds the upper limit value of the buffer occupancy value, an overflow occurs at a point indicated by a in the middle, and data loss occurs.

Therefore, as shown in FIG. 8C, the buffer occupancy value V3 of the last picture in the predetermined picture unit in the VBV is equal to the buffer occupancy value V1 (= V2).
The target code amount is set so as to be as described above. Further, the buffer occupancy value V3 and the target buffer occupancy value V1 (=
V2) is inserted as the invalid bit amount SB after the last picture in the predetermined picture unit, so that the buffer occupancy value of the last picture in VBV becomes the target buffer value. V1 (= V2)
It will be.

As described above, when the fixed transfer rate coding is performed, the coding of the GOPs before and after the connection point is started from the buffer value of a predetermined value, and the coding is terminated at the predetermined value. Thus, two video data can be connected without causing overflow.

On the other hand, if this MPEG stream is encoded at a variable transfer rate,
The overflow aborts the decoder reading, so
There is no need to insert invalid bits as in the case of the fixed transfer rate. That is, in the case of the variable transfer rate, the GOPs before and after the connection point start encoding from a buffer value of a predetermined value, and end the encoding with a value larger than the predetermined value.
At least connection that does not cause underflow can be performed. A specific encoding method based on this condition is disclosed in, for example, Japanese Patent Application Laid-Open No. 11-74799.

It is desirable that the first GOP at the above boundary is a closed GOP. A closed GOP means that when the GOP is reproduced, a reference image for predictive coding is present in the GOP,
Indicates that the forecast is complete. That is, this shows a state in which the prediction mode of the two B pictures following the I picture composed of the MPEG stream is limited to backward prediction. This can be easily realized by assuming in advance how many GOPs can be edited in encoding.

Next, an example of using edit point data will be described. Current EP of edit point data
As an example of using information, there is an example of detecting this information and determining an editable position. Returning to FIG. 1, in the main data recording / reproducing device 22, a digital signal reproduced from a position before an arbitrary editing point on a recorded magnetic tape is supplied to a control information / main data separating device 23. The control information reproduced from the sub-code area 33 of FIG. 3 and the main data reproduced from the data area 37 are separated, and the control information is supplied to the current EP detector 24, where the 4-bit data shown in FIG. Is detected, and the main data is supplied to the main data recording / reproducing device 22.

The current EP detector 24 outputs the current EP
Is supplied to the main data recording / reproducing unit 22 indicating that the timing is editable when the data is detected. Upon receiving the trigger signal, the main data recording / reproducing device 22 receives the externally input M via the terminal 21.
The compressed and encoded data of the video information and the audio information compressed by the PEG method is converted into a predetermined signal form shown in FIG. 4 and various control information is added thereto. Start editing at the edit point. This edit point is the track at the head of the boundary information where the current EP is detected, and since this track is the boundary of the ECC interleave at the beginning of the closed GOP, the VBV buffer can be connected seamlessly.

The main data recording / reproducing unit 22 has an input / output function with the memory 25, saves the recorded reproduction data in the temporary memory 25, records other input data, and then re-records the data. Editing such as storing data stored in the memory 25 is also possible.

Next, an example of using the next EP information will be described with reference to the block diagram of FIG. In the embodiment shown in FIG. 2, when editing is performed, it is used as a trigger signal for a process for making discontinuity of audio less noticeable. That is,
In the case where MPEG multiplexing is performed, if audio signals are edited in image frame units, continuous connection may not always be possible due to differences in audio frame length and video frame length. Therefore, when editing using the next EP information, the value of this next EP information bit is set to “0001”, this information is detected at the time of reproduction after editing, and the next track data is edited. As a result, it is possible to determine that the tracks are connected, and to prepare a process in which discontinuities in the sound that may occur at that time are inconspicuous as the reproduced sound.

That is, in FIG. 2, a digital signal reproduced from a position before an arbitrary edit point on a recorded magnetic tape is supplied to the control information / main data separator 23, where the sub-code area 33 shown in FIG. Is separated from the main data reproduced from the data area 37, and the control information is supplied to the next EP detector 29, where the 4-bit next EP shown in FIG. The data is supplied to a fade signal generator 28.

The fade signal generator 28 outputs the next EP
When the detection signal is input from the detector 29 as a fade start trigger signal, the fade-out of the audio data in the reproduced main data is started and the main data recording / reproducing device 2 is started.
2 together with the video data. Subsequently, when the reproduction main data falls to a predetermined level due to fade-out (or after a predetermined time has elapsed), the fade signal generator 28 outputs the MPEG signal input from the outside via the terminal 21.
Of the video and audio information compressed in accordance with the method, the audio data is switched to the compressed and coded data of the audio information (that is, audio data). Supply with video data.

Subsequently, the fade signal generator 28 stops the fade-in when the input audio data from the terminal 21 which has faded in reaches the same gain as the input audio data, and stops the fade-in. The data is directly supplied to the main data recording / reproducing device 22 together with the video data. In this way, at the editing point, the recorded audio data and the audio data input and recorded from the outside are connected at the minimum level or a level close to the minimum, so that the discontinuity of the audio is made inaudible and inconspicuous. Can be.

The main data recording / reproducing device 22 has an input / output function with respect to the memory 30, saves the recorded reproduction data to the temporary memory 30 and records the other input data to the memory 30 again. It is also possible to record the stored reproduction data.

The present invention is not limited to the above-described embodiment. For example, with regard to the compressed and coded data relating to the audio information, the mix fade (mixing the reproduced audio data before the editing point and the editing A method of mixing the input voice data after the dot and gradually lowering the mixing ratio of the former with respect to the latter over time) or starting a smooth connection of voice equivalent thereto, and using the boundary information. It is also possible to terminate the smooth connection of the sound according to the fade-in.

Further, the present invention can be applied to a digital recording / reproducing system other than D-VHS, and an optical disk or other recording media other than a magnetic tape can be used as a recording medium. Further, when the present invention is applied to a disk-shaped recording medium, the ECC interleaved block may be a predetermined sector unit. Furthermore, the current E
The P and the next EP can be recorded in a specific area (for example, a main header area) other than the subcode area of each track.

[0064]

As described above, according to the present invention,
By recording boundary information indicating whether it is the beginning or end of the N minimum editing units of the compression-encoded data for each ECC interleaved block, different information at the beginning of the minimum editing unit is determined based on the boundary information. Since the editing for connecting the compression-encoded data is performed, the editing for seamless reproduction can be performed without analyzing the contents of the compression-encoded data.

In particular, according to the present invention, M
One closed GOP is inserted in units of one or more GOPs of PEG video, and encoding is performed in consideration of seamless connection of VBV buffers. The beginning of the closed GOP is defined as the boundary of an ECC interleaved block. Since boundary information indicating the start or end of N GOPs of compressed data is recorded for each ECC interleaved block, MPEG
High-quality editing of video information can be performed without deciphering the contents of the compression-encoded data.

Further, according to the present invention, when it is detected based on the boundary existence information that the boundary information is present after a predetermined time, the level of the information signal is smoothed near the head of the minimum editing unit. Therefore, the sound reproduction starts the fade-out or the mix fade or the smooth connection of the sound similar to the sound using the boundary existence information, and the fade-in or the smooth connection of the sound similar to the sound using the boundary information. Can be ended, and high-quality editing of audio information can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention.

FIG. 2 is a block diagram of a second embodiment of the present invention.

FIG. 3 is a diagram showing an example of a track format of a recording signal of a recording medium of the present invention.

FIG. 4 is a diagram illustrating an example of a format of a sync block in a data area.

FIG. 5 is a diagram illustrating an example of a format of one sync block in a subcode area.

FIG. 6 is a diagram showing an example of a format of edit point data of a main part of the present invention.

FIG. 7 is a detailed configuration diagram of an example of edit point data;

FIG. 8 is an explanatory diagram showing a state in connection of MPEG VBV.

FIG. 9 is a block diagram illustrating an example of an encoder of the MPEG system.

FIG. 10 is a block diagram illustrating an example of an MPEG decoder.

FIG. 11 is a diagram illustrating a temporal transition of a buffer occupancy value of a VBV of MPEG.

[Description of Code] 21 Compression-encoded data input terminal 22 Main data recording / reproducing device 23 Control information / main data separator 24 Current EP detector 25, 30 Memory 28 Fade signal generator 29 Next EP detector 33 Subcode area 37 Data area 56 Subcode data area 62 Edit point data area

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H04N 7/32 G11B 27/02 A 7/24 G J (72) Inventor Seiji Higurashi 3 Moriyacho, Kanagawa-ku, Yokohama, Kanagawa Prefecture 12th Street Inside JVC

Claims (10)

[Claims] 1. A method according to claim 1, wherein the compression-encoded data is converted into a predetermined unit by an EC.
A method for recording data to be recorded on a recording medium by forming a C interleaved block, wherein the minimum unit of editing of the compression-encoded data is N ECs.
C is a data interleaved block, and records boundary information indicating whether each of the ECC interleaved blocks is a head or an end of N minimum editing units of the compressed coded data. Recording method. 2. An editing minimum unit of compression-encoded data is configured to fit into N ECC interleaved blocks, and at the beginning or end of the N editing minimum units of the compressed-encoded data for each ECC interleaved block. An editing method for editing and recording new compression-encoded data relating to arbitrary information on a recorded recording medium on which boundary information indicating whether or not there is a recorded signal is provided. An editing method, wherein the recording of the new compressed coded data is performed after waiting for detection of the boundary information indicating the start or end of the minimum editing unit from the inside. 3. An editing minimum unit of compressed encoded data is configured to fit into N ECC interleaved blocks, and at the beginning or end of the N edited minimum units of the compressed encoded data for each of the ECC interleaved blocks. An editing apparatus that edits and records new compression-encoded data relating to arbitrary information on a recorded recording medium on which boundary information indicating whether or not there is a boundary signal indicating whether there is a reproduction signal of the recorded recording medium Detecting means for detecting the boundary information from within; when a detection signal of the boundary information indicating the start or end of the minimum editing unit is input by the detecting means, the new compression-encoded data is An editing apparatus, comprising: a recording / reproducing device that performs recording on the recorded recording medium. 4. The method according to claim 1, wherein the compression-encoded data has a predetermined unit of EC.
A recording medium which forms a C interleaved block and is recorded in a predetermined format together with control information, wherein the minimum unit of editing of the compression-encoded data is N ECs
Boundary information indicating whether each of the ECC interleaved blocks is the head or the end of N minimum editing units of the compressed encoded data is recorded as a part of the control information. A recording medium characterized by being recorded. 5. The method according to claim 5, wherein the compression-encoded data is stored in a predetermined unit using an EC.
A method for recording data to be recorded on a recording medium by forming a C interleaved block, wherein the minimum unit of editing of the compression-encoded data is N ECs.
A boundary information indicating whether each of the ECC interleaved blocks is a head or an end of N minimum editing units of the compressed coded data, and the boundary information being present after a predetermined time. And a boundary existence information indicating whether or not the data is recorded. 6. The editing minimum unit of the compression-encoded data is configured to be included in N ECC interleaved blocks, and at the beginning or end of the N editing minimum units of the compressed-encoded data for each of the ECC interleaved blocks. New compressed and coded data relating to arbitrary information on a recorded recording medium in which boundary information indicating whether or not the boundary information exists and boundary existence information indicating whether the boundary information exists after a predetermined time are recorded. An editing method for editing and recording, when detecting the boundary information indicating the beginning or end of the minimum unit of editing from a reproduced signal of the recorded recording medium, the new compression encoded data And detects boundary existence information indicating that the boundary information exists after a predetermined time from a reproduction signal of the recorded recording medium. Editing, after performing fade-out or mix-fade within the predetermined time with respect to the compression-encoded data relating to audio information in the reproduction signal, performing fade-in or a connection process of audio equivalent thereto. Method. 7. The editing minimum unit of the compression-encoded data is configured to fit into N ECC interleaved blocks, and at the beginning or end of the N editing minimum units of the compressed-encoded data for each of the ECC interleaved blocks. New compressed and coded data relating to arbitrary information on a recorded recording medium in which boundary information indicating whether or not the boundary information exists and boundary existence information indicating whether the boundary information exists after a predetermined time are recorded. An editing apparatus that edits and records the boundary information, wherein first detection means for detecting the boundary information from a reproduction signal of the recorded recording medium, and the boundary existence information from a reproduction signal of the recorded recording medium. A second detection means for detecting, and a detection signal of the boundary information indicating the start or end of the minimum unit for editing by the first detection means. When the force is applied, the new compression-encoded data is recorded on the recorded recording medium, and the boundary information is determined by the second detection means from the reproduction signal of the recorded recording medium. When detecting the boundary presence information indicating that the audio signal is present after a certain time, the compressed encoded data related to the audio information in the reproduced signal is faded out or mixed faded within the predetermined time, and then fade-in or the like. An editing apparatus, comprising: a recording / reproducing unit that performs audio connection processing. 8. The method according to claim 1, wherein the compression-encoded data is EC
A recording medium which forms a C interleaved block and is recorded in a predetermined format together with control information, wherein the minimum unit of editing of the compression-encoded data is N ECs
A boundary information indicating whether each of the ECC interleaved blocks is a head or an end of N minimum editing units of the compressed coded data, and the boundary information being present after a predetermined time. A recording medium, wherein boundary existence information indicating whether or not to perform the recording is recorded as a part of the control information. 9. The minimum unit of editing of the compression-encoded data is one or a plurality of GOPs composed of video data and audio data for a plurality of frames that are compression-encoded by the MPEG method. First GOP
6. The data recording method according to claim 1, wherein the data is composed of a closed GOP. 10. The minimum unit of editing of the compression-encoded data is one or a plurality of GOPs composed of video data and audio data for a plurality of frames compression-encoded by the MPEG system. First GOP
Is composed of a closed GOP, and the GOP is a VB defined so as to encode the buffer on the decoding device side so that neither overflow nor underflow occurs.
When the occupied value of the V buffer is fixed transfer rate coding, coding is started from a predetermined first value, coding is completed with the predetermined first value, and 7. The editing method according to claim 2, wherein the encoding is started from a predetermined second value in the case, and the encoding is ended with a value larger than the predetermined second value.