JP2003009087A - Recording device and its method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent recording of a stream where an encoding amount in fixed- length unit exceeds the upper limit of an fixed-length conversion amount. SOLUTION: The stream encoded into variable length is supplied to a memory 531 and an encoding amount measuring instrument 530. The measuring instrument 530 measures the encoding amount in fixed-length unit of an input stream. Unless the measurement result exceeds a total encoding amount which is regulated concerning the fixed-length unit, the stream stored in the memory 531 is outputted and recorded in a magnetic tape 516. When the result exceeds the regulated total encoding amount, a control signal is outputted to a recording amplifier 515' to stop a recording signal. The encoding amount in fixed-length unit is measured with respect to the inputted stream and recording to the magnetic tape 516 is controlled based on the measurement result so that it is prevented to record the stream in the magnetic tape 516 which exceeds the fixed-length amount.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus and method for equalizing a data stream in a predetermined unit and recording it on a recording medium.

[0002]

2. Description of the Related Art Digital VTR (Video Tape Recorde)
As represented by r), a digital video signal and a digital audio signal are recorded on a recording medium, and
A data recording / reproducing device for reproducing from a recording medium is known. Since a digital video signal has an enormous data capacity, it is generally compressed and encoded by a predetermined method and recorded on a recording medium. In recent years, MPEG2 (M
The oving Picture Experts Group 2) method is known as a standard method of compression coding.

In the image compression techniques such as the above-mentioned MPEG2, a variable length code is used to increase the data compression rate. Therefore, the code amount after compression of data for one screen, for example, one frame or one field varies depending on the complexity of the image to be compressed.

In the above-mentioned MPEG2 system, in a data having a hierarchical structure from the lower layer to the upper layer in the order of macroblock layer, slice layer, picture layer, GOP layer and sequence layer, the slice layer serves as a unit of variable length coding. There is. The macroblock layer further includes a plurality of DCT (D
iscrete Cosine Transform) block. A header portion in which header information is stored is provided at the beginning of each layer. For example, in the slice layer, the delimiter position of the variable length code is detected by detecting this header portion. The decoder for decoding the variable-length code decodes the variable-length code based on the detected delimiter position.

Note that, for example, in MPEG2, an array of data defined by a standard is called syntax.

On the other hand, various image data formats are conceivable depending on the combination of the image size and the frame frequency, the difference in the scanning method, and the like. Video equipment for broadcasting and production generally imposes a predetermined restriction on the format of image data handled. MP mentioned above
The EG2 standard is designed to flexibly support such various image formats.

By the way, the video signal input as the baseband signal is encoded as described above,
When recording on a recording medium such as a magnetic tape, the stream of the stream is equalized in a predetermined unit, for example, a frame, by an encoder of the device. The unit of equal length varies depending on the configuration of the recording apparatus and the like, and in addition to this, for example, one field or a plurality of frames can be set as the unit of equal length. Hereinafter, it is assumed that equalization is performed in frame units. The recording area on the recording medium is divided into sizes corresponding to the equalized length, and the equalized streams are sequentially recorded in this area.

As described above, the variable-length coded stream is equalized in length and recorded on the recording medium, so that the video signal can be easily processed in frame units.

By recording the stream on the recording medium in equal length units, the recording medium is consumed in proportion to the recording time in which the equal length units are recorded. Therefore, it is possible to easily obtain accurate values of the total recording amount (recording time) and the remaining amount of the recording medium, and it is easy to find the position by high-speed search. Further, when the recording medium is a magnetic tape, there is an advantage that the magnetic tape that is dynamically driven can be stabilized by keeping it at a constant speed.

[0010]

However, when the input stream is equalized and recorded, it is guaranteed that the equalization unit, that is, the code amount for each frame is within the upper limit of the equalization length. Is not If this recording device were to record the stream frame by frame in the order in which it was input, the encoding amount of a certain frame would be the limit of the encoding amount (equalizing amount) specified for equalization. If the number exceeds, the stream of the frame is recorded only for the equal length capacity, and the code after that is divided.

When the stream of frames is divided in this way, there is a problem that the lower end of the screen is missing in the reproduced image of the frame. If the stream of frames is divided and the frame does not end normally, a syntax error may occur at the boundary with the next frame during reproduction. The syntax error has a problem that it may cause a runaway or hangup of the decoder to which the stream is input.

Further, in a recording device having a weak error resistance, which is designed on the assumption that the input stream is surely equalized in length, a failure occurs at the stage of recording a stream that exceeds the upper limit of the equalized length. There is a possibility of coming. That is, there is a problem that the code overflowing from the equalization amount enters the area in the next frame, and the capacity and recording position of the next frame is compressed by the overflow code. As a result, the meaning of lengthening the area on the recording medium is lost.

Furthermore, if the situation in which the next frame, whose capacity and recording position are compressed, further compresses the next frame, the memory of the recording system may eventually overflow. There was a point.

Therefore, an object of the present invention is to record a stream encoded in a variable length in a predetermined equalization unit such that the code amount of the equalization unit exceeds the upper limit of the equalization amount. It is an object of the present invention to provide a recording device and a method for preventing the recording of the.

[0015]

In order to solve the above-mentioned problems, the present invention provides a recording apparatus for recording a stream encoded using a variable length code on a recording medium in a predetermined equal length unit, Input means for inputting a stream encoded using a variable-length code, recording means for recording the stream input to the input means on a recording medium in a predetermined equal length unit, and stream input to the input means , A measuring unit that measures the code amount of a predetermined equal-length unit, and the code amount of the predetermined equal-length unit of the input stream to the predetermined equal-length unit based on the measurement result of the measuring unit. On the other hand, the recording apparatus has a control means for controlling so as not to record the stream exceeding the total code amount specified in the recording medium.

Further, according to the present invention, in a recording method for recording a stream encoded using a variable length code on a recording medium in a predetermined equal length unit, a stream encoded using a variable length code is input. Input step, a recording step of recording the stream input by the input step in a predetermined equalization unit, and a recording step of the stream input in the input step by a predetermined equalization unit. Based on the measurement step of measuring the code amount and the measurement result of the measurement step, the code amount of a predetermined equal length unit of the input stream is the total code amount defined for the predetermined equal length unit. And a control step of controlling so that a stream exceeding the number is not recorded on the recording medium.

As described above, according to the present invention, the stream encoded using the input variable length code is recorded on the recording medium in a predetermined equal length unit, and at that time, the input stream is The code amount of a predetermined equal-length unit is measured, and the stream in which the total code amount of the predetermined equal-length unit exceeds the code amount defined for the predetermined equal-length unit is recorded on the recording medium. Since the recording is controlled so that the recording is not performed on the recording medium, it is possible to prevent illegal recording on the recording medium when a stream having a bit rate exceeding the specified value is input.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The concept of the present invention will be described below with reference to FIGS. FIG. 1 shows a basic configuration of a digital VTR (Video Tape Recorder) that records and reproduces a baseband signal using a magnetic tape as a recording medium. At the time of recording, a baseband signal which is an uncompressed digital video signal is input from the terminal 500. The baseband signal is supplied to an ECC (Error Correction Coding) encoder 511. The baseband signal supplied to the ECC encoder 501 is subjected to shuffling and error correction coding processing, recorded and coded by the recording amplifier 502, supplied to a rotary head (not shown), and recorded on the magnetic tape 503 by the rotary head. It

At the time of reproduction, the reproduction signal reproduced by the rotary head from the magnetic tape 503 is supplied to the reproduction amplifier 504 and decoded into a digital signal. Reproduction amplifier 5
The output of 04 is supplied to the ECC decoder 505, and the error correction code is decoded and error-corrected and deshuffled. The baseband signal output from the ECC decoder 505 is led to the terminal 506.

FIG. 2 shows a basic structure of a digital VTR for recording and reproducing a stream in which a video signal is encoded by the MPEG2 system. At the time of recording, a baseband signal is input from the terminal 510 and supplied to the MPEG encoder 511. The MPEG encoder 511 encodes the supplied baseband signal in a predetermined MPEG2 system and outputs it as a stream. MPE
The stream output from the G encoder 511 is supplied to one input end of the selector 513. Also, MPE
The stream pre-encoded by the G2 method is the terminal 51.
Input from 2. This stream is a selector 513
Is supplied to the other input terminal of the.

The selector 513 selects a stream supplied to the one and the other input terminals in a predetermined manner and supplies it to the ECC encoder 514. The ECC encoder 514 performs predetermined shuffling and error correction coding processing on the stream, and the recording amplifier 515 records and codes the stream, which is supplied to a rotary head (not shown) and recorded on a magnetic tape 516.

At the time of reproduction, the reproduction signal reproduced from the magnetic tape 516 by the rotary head is supplied to the reproduction amplifier 517 and decoded into a digital signal. Reproduction amplifier 5
The output of 17 is supplied to the ECC decoder 518, the error correction code is decoded and the error is corrected, and the data is deshuffled to be an MPEG2 stream. E
The stream output from the CC decoder 518 is MP
It is also supplied to the EG decoder 520. The stream supplied to the MPEG decoder 520 is decoded into a baseband signal and is output to the terminal 521.

As described above, if the video signal can be transmitted as a stream between devices, the same number of images can be transmitted with a smaller amount of information than the baseband signal. In addition, in contrast to the baseband connection that causes the deterioration of the image quality by repeatedly decompressing and compressing the data every transmission, the image information can be transmitted without the deterioration of the image quality by the stream connection. If the image is not processed, it can be said that the stream connection is more advantageous than the baseband connection.

FIG. 3 shows the basic structure of a VTR according to the present invention. In FIG. 3, parts corresponding to those in the above-described configuration of FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted. In FIG. 3, a code amount measuring device 530 for measuring the code amount of the equal length unit in the input stream and a memory 531 are added to the configuration of FIG. The stream input from the terminal 512 is also supplied to the memory 531 and the code amount measuring device 530.
At 30, the code amount of the equal length unit, which is, for example, one frame, is measured.

If the code amount measured by the code amount measuring device 530 exceeds the prescribed value prescribed for the equal-length unit, the code amount measuring device 530 sends a stream magnetic tape. A control signal for controlling recording on 516 is output. In the example of FIG. 3, this control signal is supplied to the recording amplifier 515 ', and the output of the recording RF signal is stopped. Further, the control signal may be supplied to a servo circuit (not shown) to stop the recording operation itself.

As described above, the input side measures the code amount in the equal length unit of the input stream and controls the recording based on the measurement result, so that the code amount in the equal length unit is the specified amount. It is possible to prevent the above stream from being recorded on the recording medium.

The memory 531 is used by the code amount measuring device 53.
It is provided to prevent the input stream from being recorded on the magnetic tape 516 before the measurement result of 0 is obtained. For example, if a sufficient delay can be obtained by the processing in the ECC encoder 514, the memory 531 is unnecessary.

Next, an example in which the first embodiment is applied to a digital VTR will be described. This digital VTR is suitable for use in the environment of a broadcasting station, and enables recording / reproduction of video signals of a plurality of different formats.

The application example of the first embodiment described below can be similarly applied to the second to fifth embodiments described later.

In the first embodiment of the present invention, for example, the MPEG2 system is adopted as the compression system. MPEG2
Is a combination of motion compensation predictive coding and compression coding by DCT. The data structure of MPEG2 has a hierarchical structure. FIG. 4 shows a general MPEG.
2 schematically shows the hierarchical structure of two data streams. Figure 4
As shown in FIG. 3, the data structure is, from the bottom, a macroblock layer (FIG. 4E), a slice layer (FIG. 4D), a picture layer (FIG. 4C), a GOP layer (FIG. 4B) and a sequence layer (FIG. 4A). ing.

As shown in FIG. 4E, the macroblock layer is composed of DCT blocks which are units for performing DCT. The macroblock layer is composed of a macroblock header and a plurality of DCT blocks. The slice layer is shown in Figure 4.
As shown in D, it is composed of a slice header part and one or more macroblocks. As shown in FIG. 4C, the picture layer is composed of a picture header section and one or more slices. A picture corresponds to one screen.
As shown in FIG. 4B, the GOP layer includes a GOP header portion, an I picture that is a picture based on intra-frame coding, and P and B pictures that are pictures based on predictive coding.

An I-picture (Intra-coded picture) uses information closed in only one picture when it is coded. Therefore, at the time of decoding, only the information of the I picture itself can be used for decoding. A P-picture (Predictive-coded picture) uses a previously decoded I-picture or P-picture that is temporally previous as a predictive picture (picture that serves as a reference for taking a difference). . Whether to code the difference from the motion-compensated predicted image, or to code without taking the difference,
Select the most efficient one in macroblock units. A B picture (Bidirectionally predictive-coded picture) is a previously decoded I picture or P picture that is temporally preceding, and a temporally posterior picture that is a temporally posterior picture. Three types of I-pictures or P-pictures already decoded as well as interpolated pictures made from both are used. Of the three types of differential encoding after motion compensation and intra encoding, the most efficient one is selected in macroblock units.

Therefore, as the macro block type,
Intra-frame coding (Intra) macroblocks, forward predicting the future from the past (Forward) inter-frame prediction macroblocks, and backward predicting the past from the future (Backward)
There are inter-frame prediction macroblocks and bidirectional macroblocks predicted from both front and back directions. All macroblocks in an I picture are intra-frame coded macroblocks. In addition, an intra-frame encoded macroblock and a forward inter-frame prediction macroblock are included in the P picture. B-pictures include all four types of macroblocks described above.

A GOP contains at least one I picture, and P and B pictures are allowed even if they do not exist. As shown in FIG. 4A, the uppermost sequence layer is composed of a sequence header part and a plurality of GOPs.

In the MPEG format, a slice is a variable length code sequence. The variable-length code sequence is a sequence in which a data boundary cannot be detected unless the variable-length code is correctly decoded.

At the beginning of each of the sequence layer, GOP layer, picture layer and slice layer, a start code having a predetermined bit pattern arranged in byte units is arranged. This start code arranged at the beginning of each layer is called a sequence header code in the sequence layer and a start code in the other layers, and the bit pattern is [00 00 01 xx] (hexadecimal notation). Two digits are shown, and [xx] indicates that different bit patterns are arranged in each layer.

That is, the start code and the sequence header code are composed of 4 bytes (= 32 bits), and the type of information that follows can be identified based on the value of the 4th byte. Since these start code and sequence header code are aligned in byte units, they can be captured only by performing 4-byte pattern matching.

Further, the upper 4 bits of 1 byte following the start code serve as an identifier of the contents of the extended data area described later. The content of the extended data can be determined by the value of this identifier.

It should be noted that such an identification code having a predetermined bit pattern aligned in byte units is not arranged in the macro block layer and the DCT block in the macro block.

The header section of each layer will be described in more detail. In the sequence layer shown in FIG. 4A, the sequence header 2 is arranged at the beginning, and subsequently the sequence extension 3, the extension and the user data 4 are arranged. Sequence header 2
A sequence header code 1 is placed at the beginning of the. Although not shown, a predetermined start code is also placed at the beginning of each of the sequence extension 3 and the user data 4. The sequence header 2 to the extension and user data 4 are used as the header portion of the sequence layer.

In the sequence header 2, as shown in FIG. 5, the contents of each parameter and the allocated bits are shown, the sequence header code 1, the encoded image size consisting of the number of pixels in the horizontal direction and the number of lines in the vertical direction, the aspect ratio, and the frame. Bit rate, VBV (Video Buffering Verif)
ier) Information set in sequence units, such as a buffer size and a quantization matrix, is stored by allocating a predetermined number of bits.

In FIG. 5 and each of FIGS. 15 to 15 described later, some parameters are omitted in order to avoid complexity.

In the sequence extension 3 after the extension start code following the sequence header, as shown in FIG.
Additional data such as profile, level, color difference format, and progressive sequence used in MPEG2 are designated. As shown in FIG. 7, the extension and user data 4 can store the information of the RGB conversion characteristics of the original signal and the display image size by the sequence display (), and the scalability and the scalability of the scalability mode and the scalability by the sequence scalable extension (). You can specify layers.

Following the header of the sequence layer, GOP
Are arranged. At the beginning of the GOP, as shown in FIG. 4B, a GOP header 6 and user data 7 are arranged.
The GOP header 6 and the user data 7 are used as the header part of the GOP. As shown in FIG. 8, the GOP header 6 includes a GOP start code 5, a time code, and a GOP.
Flags indicating independence and legitimacy of are assigned a predetermined number of bits and stored. The user data 7 includes extension data and user data, as shown in FIG. Although not shown, a predetermined start code is placed at the beginning of each of the extension data and the user data.

A picture is arranged following the header part of the GOP layer. As shown in FIG. 4C, a picture header 9, a picture coding extension 10, and extension and user data 11 are arranged at the head of the picture. A picture start code 8 is arranged at the head of the picture header 9. A predetermined start code is arranged at the beginning of each of the picture coding extension 10 and the extension and user data 11. The picture header 9 to the extension and user data 11 are the header part of the picture.

As shown in FIG. 10, the picture header 9 is provided with a picture start code 8 and is set with a coding condition for the screen. In the picture coding extension 10, as shown in FIG. 11, the range of the motion vector in the front-back direction and the horizontal / vertical direction and the picture structure are specified. Also, picture coding extension 1
At 0, the DC coefficient precision of the intra macroblock is set, the VLC type is selected, the linear / non-linear quantization scale is selected, and the scanning method in the DCT is selected.

In the extension and user data 11, FIG.
As shown in, the quantization matrix setting, the spatial scalable parameter setting, and the like are performed. These settings are possible for each picture, and encoding can be performed according to the characteristics of each screen. In the extension and user data 11, it is possible to set the display area of the picture. Further, copyright information can be set in the extension and user data 11.

Slices are arranged following the header part of the picture layer. As shown in FIG. 4D, the slice header 13 is arranged at the head of the slice, and the slice head 1
A slice start code 12 is placed at the beginning of the number 3.
As shown in FIG. 13, slice start code 12
Includes vertical position information of the slice. The slice header 13 further stores extended slice vertical position information, quantization scale information, and the like.

Macroblocks are arranged following the header of the slice layer (FIG. 4E). In the macroblock, a plurality of DCT blocks are arranged following the macroblock header 14. As mentioned above, macroblock header 1
No start code is assigned to 4. As shown in FIG. 14, the macroblock header 14 stores relative position information of macroblocks, and instructs the setting of the motion compensation mode, the detailed setting regarding DCT coding, and the like.

Following the macroblock header 14, DC
T blocks are arranged. The DCT block includes variable length coded DCT coefficients and D as shown in FIG.
Data regarding the CT coefficient is stored.

In FIG. 4, solid line delimiters in each layer indicate that data is aligned in byte units, and dotted line delimiters indicate that data is not aligned in byte units. That is, up to the picture layer, as shown in FIG.
As shown in an example in FIG. 6A, the boundaries of the code are divided in byte units, whereas in the slice layer, only the slice start code 12 is divided in byte units, and each macroblock is shown in FIG. 16B. As shown in the example, the data can be divided bit by bit. Similarly, in the macroblock layer, each DCT block can be divided in bit units.

On the other hand, in order to avoid signal deterioration due to decoding and coding, it is desirable to edit the coded data. At this time, the P picture and the B picture require temporally previous pictures or temporally previous and subsequent pictures for decoding. Therefore, the editing unit cannot be one frame. In consideration of this point, in the first embodiment, one GOP is made up of one I picture.

Further, for example, the recording area in which the recording data for one frame is recorded is predetermined. MPEG2
Since variable length coding is used, the amount of generated data for one frame is controlled so that the data generated in one frame period can be recorded in a predetermined recording area. Further, in the first embodiment, one slice is made up of one macroblock and one macroblock is applied to a fixed frame having a predetermined length so as to be suitable for recording on a magnetic tape.

FIG. 17 shows the M according to the first embodiment of the present invention.
The header of the PEG stream is specifically shown. As can be seen from FIG. 4, the header parts of the sequence layer, GOP layer, picture layer, slice layer, and macroblock layer continuously appear from the beginning of the sequence layer. FIG. 17
Indicates an example data array that is continuous from the sequence header portion.

A sequence header 2 having a length of 12 bytes is arranged from the beginning, and a sequence extension 3 having a length of 10 bytes is arranged subsequently. Next to the sequence extension 3, extension and user data 4 are arranged.
A 4-byte user data start code is placed at the beginning of the extension and user data 4, and information based on the SMPTE standard is stored in the subsequent user data area.

Next to the header part of the sequence layer is the header part of the GOP layer. A GOP header 6 having a length of 8 bytes is arranged, followed by extension and user data 7. A 4-byte user data start code is placed at the beginning of the extension and user data 7, and the following user data area stores information for compatibility with other existing video formats.

The header of the GOP layer is followed by the header of the picture layer. A picture header 9 having a length of 9 bytes is arranged, followed by a picture coding extension 10 having a length of 9 bytes. After the picture coding extension 10, extension and user data 11 are arranged. Expansion and user data are stored in the leading 133 bytes of the expansion and user data 11, and subsequently, a user data start code 15 having a length of 4 bytes is arranged. Following the user data start code 15, information for compatibility with other existing video formats is stored. Further, a user data start code 16 is provided, and following the user data start code 16, SMP
Data based on the TE standard is stored. Next to the header part of the picture layer is a slice.

The macroblock will be described in more detail. The macroblock included in the slice layer is a set of a plurality of DCT blocks, and the encoded sequence of the DCT block is a sequence of quantized DCT coefficients, the number of consecutive 0 coefficients (run) and a non-zero sequence immediately after that. This is a variable-length code in which (level) is one unit. For macroblocks and DCT blocks within macroblocks,
The identification code arranged in byte units is not added.

The macroblock has a screen (picture) of 1
It is divided into a grid of 6 pixels × 16 lines. The slice is formed by connecting the macroblocks in the horizontal direction, for example. The last macroblock of a slice before a continuous slice and the first macroblock of the next slice are continuous, and it is not allowed to form a macroblock overlap between slices. Further, when the screen size is determined, the number of macroblocks per screen is uniquely determined.

The numbers of macroblocks in the vertical and horizontal directions on the screen are set to mb_height and m, respectively.
It is called b_width. The coordinates of the macroblock on the screen are mb_row, which is the vertical position number of the macroblock, which is counted from 0 based on the upper end, and mb_colu, which is the horizontal position number of the macroblock, which is counted from 0 based on the left end.
mn and mn. In order to represent the position of the macro block on the screen with one variable, macro
block_address to macroblock
_Address = mb_row × mb_width +
mb_column Defined like this.

It is specified that the order of slices and macroblocks on a stream must be in the order of smaller macroblock_address. That is, the stream is transmitted from the top to the bottom of the screen and from the left to the right.

In MPEG, one slice is usually composed of one stripe (16 lines), and variable length coding starts from the left end of the screen and ends at the right end. Therefore, V
When the MPEG elementary stream is recorded as it is by TR, the reproducible portion is concentrated on the left end of the screen during high-speed reproduction, and it cannot be uniformly updated. Further, since the arrangement of the data on the tape cannot be predicted, even if the tape pattern is traced at regular intervals, the uniform screen update cannot be performed. Furthermore, if an error occurs even at one location, it affects the right edge of the screen and cannot recover until the next slice header is detected. For this reason, one slice is made up of one macroblock.

FIG. 18 shows an example of the structure on the recording side of the recording / reproducing apparatus applicable to the first embodiment. At the time of recording, the digital signal input from the terminal 100 is SD
It is supplied to the I (Serial Data Interface) receiving unit 101. SDI is an interface defined by SMPTE for transmitting (4: 2: 2) component video signals, digital audio signals, and additional data. The SDI receiving unit 101 extracts the digital video signal and the digital audio signal from the input digital signal, supplies the digital video signal to the MPEG encoder 102, and the digital audio signal passes through the delay 103 to the ECC encoder 109. Is supplied to. The delay 103 is for eliminating the time difference between the digital audio signal and the digital video signal.

Further, the SDI receiving section 101 extracts a sync signal from the input digital signal and supplies the extracted sync signal to the timing generator 104. An external synchronization signal can be input to the timing generator 104 from the terminal 105. The timing generator 104 generates a timing pulse on the basis of a designated signal among these input synchronizing signals and the synchronizing signal supplied from the SDTI receiving unit 108 described later. The generated timing pulse is supplied to each part of this recording / reproducing apparatus.

The input video signal is the MPEG encoder 1
In 02, a DCT (Discrete Cosine Transform) process is performed, the coefficient data is converted, and the coefficient data is variable-length coded. The variable length coded (VLC) data from the MPEG encoder 102 is an elementary stream (ES) compliant with MPEG2. This output is supplied to one input end of a recording-side multi-format converter (hereinafter referred to as MFC) 106.

On the other hand, through the input terminal 107, SDTI
Data in the (Serial Data Transport Interface) format is input. This signal is sent to the SDTI receiver 10
The synchronization is detected at 8, and is temporarily stored in the frame memory 170. The synchronization signal obtained by the synchronization detection is supplied to the timing generator 104 described above. The signals stored in the frame memory 170 are recorded on the recording side M which will be described later.
It is read according to the request signal RQ supplied from the FC 106, the elementary stream is extracted, and SD
It is output from the TI receiving unit 108. At this time, SDTI
The enable signal EN indicating the valid period of the output elementary stream is output from the receiving unit 108.

Request signal RQ of recording side MFC 106
The elementary stream output from the SDTI receiving unit 108 is supplied to the code amount measuring unit 560 according to FIG.
As described above by using, the code amount is temporarily stored in the memory 531 and the code amount measuring unit 530 measures the code amount of the equal length unit. The equal length unit is, for example, one frame of a video signal.

In the first embodiment, when the code amount of the equal length unit exceeds the total code amount defined for the equal length unit, it is input based on the measurement result of the code amount. A control signal for stopping the recording of the stream is output from the code amount control unit 560. This control signal is supplied to, for example, an equalizer 110 described later, and when the code amount of the equalization unit exceeds the total code amount specified for the equalization unit, the recording RF signal from the equalizer 110 is output. The output is stopped under the control of this control signal. Recording may be stopped by providing a switch circuit between the equalizer 110 and a magnetic head mounted on a rotary drum 111, which will be described later, and controlling the open / closed state of the switch circuit by a control signal. The code amount measuring unit 56
Details of the processing by 0 will be described later.

When this configuration is applied to the second to fifth embodiments described later, the output of the control signal from the code amount measuring section 560 and the equalizer 1 based on the control signal.
Controls such as 10 are unnecessary.

M whose code amount is measured by the code amount measuring unit 56
The PEG ES is supplied to the other input end of the recording MFC 106.

In the present invention, for example, MPEG ES (M
In order to transmit a PEG elementary stream)
DTI (Serial Data Transport Interface) -CP (Con
tentPackage) is used. This ES is 4: 2: 2
In addition, as described above, all are I-picture streams and have a relationship of 1 GOP = 1 picture. In SDTI-CP format,
MPEG ES is separated into access units, and
It is packed in packets in frame units. SD
In TI-CP, a sufficient transmission band (2 at the clock rate
7MHz or 36MHz, 27 at stream bit rate
0 M bps or 360 M bps) is used, and ES can be sent in a burst in one frame period.

That is, the system data, the video stream, the audio stream, and the AUX data are arranged between the SAV of one frame period and the EAV.
The data does not exist in the entire one frame period, but the data exists in a burst form for a predetermined period from the beginning thereof. SDTI-CP streams (video and audio) can be switched in a stream state at frame boundaries. SDTI-CP has a mechanism for establishing synchronization between audio and video in the case of content using SMPTE time code as a clock reference. Furthermore, the format is determined so that SDTI-CP and SDI can coexist.

In the interface using SDTI-CP described above, the encoder and the decoder use VBV (Video B) as in the case of transferring TS (Transport Stream).
uffer Verifier) buffer and TBs (Transport Buf)
You don't have to go through the fers) and you can reduce the delay. Also, the fact that SDTI-CP itself can perform extremely high-speed transfer further reduces the delay. Therefore, in an environment where synchronization exists that manages the entire broadcasting station, SDTI-
It is effective to use CP.

The SDTI receiving section 108 further extracts a digital audio signal from the input SDTI-CP stream. The extracted digital audio signal is supplied to the ECC encoder 109.

The recording MFC 106 has a built-in selector and stream converter. Furthermore, the code amount measuring unit 560 described above can be incorporated in the recording MFC 106. The recording MFC 106 is configured in, for example, one integrated circuit. The processing performed in the recording MFC 106 will be described. The MP supplied from the MPEG encoder 102 and the SDTI receiving unit 108 described above.
One of EG ES is selected by the selector and supplied to the stream converter.

The stream converter has a simple decoder that only decodes variable-length codes, for example. The MPEG ES supplied to the stream converter is simply decoded, and the DCT coefficients arranged for each DCT block based on the MPEG2 standard are combined for each frequency component through a plurality of DCT blocks forming one macroblock. , The sorted frequency components are rearranged. Further, by the stream converter, when one slice of the elementary stream has one stripe, one slice is made up of one macroblock. Furthermore, the stream converter limits the maximum length of variable length data generated in one macroblock to a predetermined length. This can be done by setting the high-order DCT coefficient to 0. The rearranged converted elementary stream is supplied to the ECC encoder 109.

The ECC encoder 109 is connected to a large-capacity main memory (not shown), and has a packing and shuffling section, an audio outer code encoder, a video outer code encoder, an inner code encoder, an audio shuffling section, and a video. It has a built-in shuffling part. The ECC encoder 109 also includes a circuit that adds an ID in sync block units and a circuit that adds a synchronization signal. The ECC encoder 109 is composed of, for example, one integrated circuit.

In the first embodiment, the product code is used as the error correction code for the video data and audio data. The product code is a code in which an outer code is encoded in the vertical direction of a two-dimensional array of video data or audio data, an inner code is encoded in the horizontal direction, and a data symbol is doubly encoded. Reed-Solomon code (Reed-Solo code)
mon code) can be used.

The processing in the ECC encoder 109 will be described. Since the video data of the elementary stream is variable-length coded, the data lengths of the macroblocks are not uniform. In the packing and shuffling section, macro blocks are packed in a fixed frame. At this time, the overflow portion protruding from the fixed frame is sequentially packed in an area vacant with respect to the size of the fixed frame.

Further, system data having information such as image format, shuffling pattern version, etc. is supplied from the system controller 121, which will be described later, and inputted from an input end (not shown). The system data is supplied to the packing and shuffling unit and subjected to the recording process like the picture data. Further, shuffling is performed to rearrange the macroblocks of one frame that occur in the scanning order and to distribute the recording positions of the macroblocks on the tape. The shuffling can improve the image update rate even when the data is fragmentarily reproduced during variable speed reproduction.

Video data and system data from the packing and shuffling unit (hereinafter, simply referred to as video data even when including system data unless otherwise required) are coded by outer coding with respect to the video data. Is supplied to the outer code encoder for video, and the outer code parity is added. The output of the outer code encoder is shuffled by switching the order in sync block units over a plurality of ECC blocks in a video shuffling unit. Shuffling in sync block units prevents errors from concentrating on a specific ECC block. The shuffling performed by the shuffling section may be referred to as interleave. The output of the video shuffling unit is written in the main memory.

On the other hand, as described above, the SDTI receiver 1
08 or the digital audio signal output from the delay 103 is supplied to the ECC encoder 109. In the first mode of this embodiment, an uncompressed digital audio signal is handled. The digital audio signal is not limited to these, and may be input via an audio interface. An audio AUX is supplied from an input terminal (not shown). The audio AUX is auxiliary data, and is data having information related to the audio data such as a sampling frequency of the audio data. The audio AUX is added to the audio data and treated in the same manner as the audio data.

The audio data to which the audio AUX is added (hereinafter, simply referred to as audio data when including the AUX, unless otherwise required) is an outer code for audio that encodes the outer code with respect to the audio data. Supplied to the encoder. The output of the audio outer code encoder is supplied to the audio shuffling unit and subjected to shuffling processing. As audio shuffling, shuffling in sync block units and shuffling in channel units are performed.

The output of the audio shuffling section is written in the main memory. As described above, the output of the video shuffling unit is also written in the main memory, and the audio data and the video data are mixed in the main memory to form one-channel data.

Data is read from the main memory, an ID having information indicating the sync block number and the like is added, and the data is supplied to the inner code encoder. The inner code encoder encodes the supplied data with an inner code. A sync signal for each sync block is added to the output of the inner code encoder to form recording data in which sync blocks are continuous.

The recording data output from the ECC encoder 109 is supplied to an equalizer 110 including a recording amplifier and converted into a recording RF signal. The recording RF signal is supplied to the rotary drum 111 provided with a predetermined rotary head and recorded on the magnetic tape 112. A plurality of magnetic heads having different azimuths of heads forming adjacent tracks are actually attached to the rotary drum 111.

Note that, as described above, the equalizer 110
Then, the output of the recording RF signal is controlled based on the control signal supplied from the code amount measuring unit 560. The invention is not limited to this, and a switch circuit whose opening and closing is controlled by a control signal supplied from the code amount measuring unit 560 may be provided between the equalizer 110 and the rotating drum 111.

The recording data may be scrambled if necessary. Also, digital modulation may be performed during recording, and partial response class 4 and Viterbi code may be used. The equalizer 110 includes both a recording-side configuration and a reproduction-side configuration.

FIG. 19 shows an example of a track format formed on a magnetic tape by the above rotary head. In this example, video and audio data per frame is recorded in 4 tracks. One segment is composed of two tracks of different azimuths. That is, 4 tracks consist of 4 segments. Track number corresponding to azimuth for one set of tracks that make up a segment

[0] and track number [1] are added. In each of the tracks, video sectors on which video data is recorded are arranged on both ends,
An audio sector in which audio data is recorded is arranged between the video sectors. FIG. 19 shows the arrangement of sectors on the tape.

In this example, 4-channel audio data can be handled. A1 to A4
Indicates channels 1 to 4 of audio data, respectively. The audio data is recorded by changing the arrangement for each segment. In this example, the video data is interleaved with data for four error correction blocks for one track, and Upper Side and Lowe
It is recorded by being divided into r Side sectors.

The lower side video sector has a system area (SY) in which system data is recorded.
S) is provided at a predetermined position. The system area is alternately provided for each track on the leading side and the trailing side of the lower side video sector.

Incidentally, in FIG. 19, SAT is an area in which a signal for servo lock is recorded. Further, a gap having a predetermined size is provided between each recording area.

FIG. 19 shows data of 4 per frame.
Although an example of recording by tracks is used, data per frame can be recorded by 8 tracks, 6 tracks, etc. depending on the format of data to be recorded and reproduced.

As shown in FIG. 19B, the data recorded on the tape is composed of a plurality of blocks called sync blocks which are divided at equal intervals. FIG. 19C schematically shows the structure of a sync block. The sync block is
It is composed of a SYNC pattern for detecting synchronization, an ID for identifying each sync block, a DID indicating the content of subsequent data, a data packet and an inner code parity for error correction. Data is handled as a packet in sync block units. That is, the smallest data unit to be recorded or reproduced is one sync block. Many sync blocks are lined up (Fig. 1
9B), for example a video sector is formed.

FIG. 19D shows an example of the data structure of the system area SYS. In the data area in the sync block shown in FIG. 19C, 5 bytes are allocated to the system data, 2 bytes to the MPEG header, 10 bytes to the picture information, and 92 bytes to the user data from the beginning.

In the system data, the presence or absence of switching points and their positions, video formats (frame frequency, interleaving method, aspect ratio, etc.), shuffling version information, etc. are recorded. Further, in the system data, an appropriate level of the recorded MPEG ES syntax is recorded using 6 bits.

In the MPEG header, MPEG header information necessary for shuttle reproduction is recorded. Information for maintaining compatibility with other digital VTRs is recorded in the picture information. Further, the date of recording and the cassette number are recorded in the user data.

Returning to the explanation of FIG. 18, at the time of reproduction, the reproduction signal reproduced from the magnetic tape 112 on the rotary drum 111 is supplied to the reproduction side structure of the equalizer 110 including a reproduction amplifier and the like. The equalizer 110 performs equalization and waveform shaping on the reproduced signal. In addition, demodulation of digital modulation, Viterbi decoding and the like are performed as necessary.
The output of the equalizer 110 is supplied to the ECC decoder 113.

The ECC decoder 113 uses the ECC described above.
It performs a process reverse to that of the encoder 109, and includes a large-capacity main memory, an inner code decoder, audio and video deshuffling units, and an outer code decoder. Further, the ECC decoder 113 includes a deshuffling and depacking unit and a data interpolation unit for video. Similarly, for audio, an audio AUX separation unit and a data interpolation unit are included. The ECC decoder 113 is composed of, for example, one integrated circuit.

The processing in the ECC decoder 113 will be described. The ECC decoder 113 first performs synchronization detection, detects a synchronization signal added to the head of the sync block, and cuts out the sync block. The reproduced data is supplied to the inner code encoder for each sync block, and the inner code is error-corrected. ID interpolation processing is performed on the output of the inner code encoder, and the ID of the sync block that has been determined to be an error by the inner code, for example, the sync block number is interpolated. The reproduction data in which the ID is interpolated is separated into video data and audio data.

As described above, the video data is MPE
It means DCT coefficient data and system data generated by G intra-coding, and audio data is PCM.
(Pulse Code Modulation) Data and audio AU
Means X.

The separated audio data is supplied to the audio deshuffling section, and the processing opposite to the shuffling performed in the recording side shuffling section is performed. The output of the deshuffling unit is supplied to the outer code decoder for audio, and error correction is performed by the outer code. Error-corrected audio data is output from the audio outer code decoder. An error flag is set for data with uncorrectable errors.

The audio AUX separating unit separates the audio AUX from the output of the outer code decoder for audio, and the separated audio AUX is the ECC decoder 1.
13 is output (the route is omitted). Audio A
The UX is supplied to, for example, the syscon 121 described later.
Also, the audio data is supplied to the data interpolation unit. The data interpolating unit interpolates a sample having an error. As the interpolation method, average value interpolation for interpolating with the average value of correct data before and after temporally, previous value hold for holding the value of the previous correct sample, and the like can be used.

The output of the data interpolation unit is the ECC decoder 11
Audio data output from the ECC decoder 113 is output to the delay 117 and the SDTI output unit 115. The delay 117 is provided to absorb a delay due to processing of video data by the MPEG decoder 116 described later. The audio data supplied to the delay 117 is given a predetermined delay and then supplied to the SDI output unit 118.

The separated video data is supplied to the deshuffling section and processed in the reverse of the shuffling on the recording side. The deshuffling unit restores the shuffling in sync block units performed by the shuffling unit on the recording side. The output of the deshuffling unit is supplied to the outer code decoder, and error correction is performed using the outer code. When an uncorrectable error occurs, an error flag indicating the presence / absence of an error indicates that there is an error.

The output of the outer code decoder is supplied to the deshuffling and depacking section. The deshuffling and depacking unit performs a process of returning the shuffling performed in the packing and shuffling units on the recording side in macroblock units. In the deshuffling and depacking section, the packing applied during recording is disassembled. That is, the length of data is returned in units of macroblocks to restore the original variable length code. Further, in the deshuffling and depacking unit, the system data is separated, output from the ECC decoder 113, and supplied to the syscon 121 described later.

The output of the deshuffling and depacking section is supplied to the data interpolating section, and the data having an error flag (that is, having an error) is corrected.
That is, if it is determined that there is an error in the middle of the macroblock data before conversion, the DCT coefficient of the frequency component after the error location cannot be restored. Therefore, for example, the data at the error location is replaced with a block end code (EOB), and the DCT coefficient of the frequency components thereafter is set to zero.
Similarly, even during high-speed reproduction, only the DCT coefficients up to the length corresponding to the sync block length are restored, and the coefficients after that are replaced with zero data. Further, the data interpolating unit also performs processing for recovering the header (sequence header, GOP header, picture header, user data, etc.) when the header added to the beginning of the video data is in error.

Since the DCT coefficients are arranged from the DC component and the low frequency component to the high frequency component across the DCT block, even if the DCT coefficient is ignored from a certain point onward, the macro block It is possible to evenly distribute DCT coefficients from DC and low-frequency components to each of the DCT blocks constituting the.

The video data output from the data interpolating unit is the output of the ECC decoder 113, and the output of the ECC decoder 113 is supplied to the multi-format converter on the reproducing side (hereinafter, abbreviated as MFC on the reproducing side) 114. . The reproduction side MFC 114 is the recording side MFC 1 described above.
It performs the reverse processing of 06 and includes a stream converter. The reproducing MFC 114 is composed of, for example, one integrated circuit.

The stream converter performs the reverse process of the recording side stream converter. That is, D
The DCT coefficients that were arranged for each frequency component across the CT blocks are rearranged for each DCT block. As a result, the reproduction signal is converted into an MPEG2-compliant elementary stream.

The input / output of the stream converter is
Similar to the recording side, a sufficient transfer rate (bandwidth) is secured according to the maximum length of the macroblock. When the length of the macro block (slice) is not limited, it is preferable to secure a bandwidth that is three times the pixel rate.

The output of the stream converter is the reproduction side MF.
The output of the reproduction side MFC 114, which is the output of the C114, is the SDTI output unit 115 and the MPEG decoder 11.
6 is supplied.

The MPEG decoder 116 decodes the elementary stream and outputs video data. That is, the MPEG decoder 142 performs the inverse quantization process and the inverse D
CT processing is performed. The decoded video data is supplied to the SDI output unit 118. As described above, the audio data separated from the video data by the ECC decoder 113 is supplied to the SDI output unit 118 via the delay 117. The SDI output unit 118 maps the supplied video data and audio data into an SDI format and converts the stream into a stream having a data structure of the SDI format. SDI output section 11
The stream from 8 is output from the output terminal 120 to the outside.

On the other hand, the SDTI output section 115 is supplied with the audio data separated from the video data by the ECC decoder 113 as described above. The SDTI output unit 115 receives the SDT of the supplied video data as an elementary stream and audio data.
It is mapped to the I format and converted into a stream having a data structure of the SDTI format. The converted stream is output from the output terminal 119 to the outside.

In FIG. 18, the system controller 121 is composed of, for example, a microcomputer, and controls the overall operation of this recording / reproducing apparatus. Further, when switches provided on a control panel (not shown) are operated, a control signal corresponding to the operation is supplied to the sys-con 121. Based on this control signal, the syscon 121 controls operations such as recording and reproducing in this recording / reproducing apparatus. As an example, the recording switch 55 provided on the control panel
By operating 1, the input terminal 100 and the input terminal 107
The operation of recording the video signal input from the magnetic tape 112 is started.

Further, the control panel has an LCD
A display unit such as (Liquid Crystal Display) can be provided (not shown). Based on the display control signal generated by the system controller 121, a predetermined display is displayed on the display unit. Each state of the recording / reproducing apparatus is displayed on the display unit.

The servo 122 controls the running of the magnetic tape 112 and the drive of the rotary drum 111 while communicating with the system controller 121. Also, the servo 12
At 2, the acceleration state of the rotating drum 111 is detected. The acceleration state is detected, for example, by examining the temporal change of the FG pulse or PG pulse interval of the rotating drum 111. The detection result is a syscon 1 as a drum acceleration detection signal.
21.

FIG. 20A shows the order of DCT coefficients in the video data output from the DCT circuit of the MPEG encoder 102. M output from the SDTI receiving unit 108
The same applies to PEG ES. In the following, MPE
The output of the G encoder 102 will be described as an example. DC
Starting from the DC component at the upper left of the T block, DCT coefficients are output in a zigzag scan in the direction in which the horizontal and vertical spatial frequencies increase. As a result, FIG.
As shown in FIG. 1, a total of 64 (8 pixels × 8 lines) DCT coefficients are arranged in order of frequency components.

This DCT coefficient is the V of the MPEG encoder.
Variable length coding is performed by the LC unit. That is, the first coefficient is fixed as the DC component and the second component (AC
Component), a code is assigned corresponding to a run of zeros and subsequent levels. Therefore, the variable-length coded output for the coefficient data of the AC component is such that the coefficient of the frequency component is low (low order) to high (high order), AC ₁ ,
AC ₂ , AC ₃ , ... Are arranged. The elementary stream includes DCT coefficients that have been variable-length coded.

In the recording side stream converter incorporated in the recording side MFC 106, the DCT coefficients of the supplied signals are rearranged. That is, in each macroblock, the DCT coefficients arranged in the frequency component order in each DCT block by the zigzag scan are rearranged in the frequency component order in each DCT block forming the macroblock.

FIG. 21 schematically shows rearrangement of DCT coefficients in this recording side stream converter.
In the case of a (4: 2: 2) component signal, one macroblock includes four DCT blocks (Y ₁ , Y ₂ , Y ₃ and Y ₄ ) based on the luminance signal Y and chromaticity signals Cb and C.
Two DCT blocks (C
b ₁ , Cb ₂ , Cr ₁ and Cr ₂ ).

As described above, the MPEG encoder 10
In 2, the zigzag scan is performed in accordance with the regulations of MPEG2, and as shown in FIG. 21A, the DCT coefficients are arranged in order from the DC component and the low frequency component to the high frequency component in the order of the frequency component for each DCT block. When the scan of one DCT block is completed, the scan of the next DCT block is performed, and the DCT coefficients are arranged in the same manner.

That is, within the macroblock, the DCT block is
Lock Y₁, Y₂, Y₃And Y_Four, DCT block C
b₁, Cb₂, Cr₁And Cr₂For each of
The DCT coefficient is from DC component and low frequency component to high frequency component
Are arranged in order of frequency. And a series of runs
In the set consisting of the following level, [DC, AC₁, AC
₂, AC₃, ...]
As described above, variable length coding is performed.

In the recording-side stream converter, the variable-length coded and arranged DCT coefficients are once decoded into the variable-length codes to detect the division of each coefficient, and the DCT coefficients are divided into the DCT blocks constituting the macroblock. Collect by frequency component. This is shown in FIG. 21B. First, the DC components of the eight DCT blocks in the macroblock are grouped together, then the AC coefficient components having the lowest frequency components of the eight DCT blocks are grouped together, and hereinafter, the AC coefficients of the same order are grouped in order. The coefficient data is rearranged across the DCT blocks.

The rearranged coefficient data is DC
(Y₁), DC (Y₂), DC (Y₃), DC
(Y_Four), DC (Cb₁), DC (Cb₂), DC (C
r₁), DC (Cr ₂), AC₁(Y₁), AC₁(Y
₂), AC₁(Y₃), AC₁(Y_Four), AC₁(Cb
₁), AC₁(Cb₂), AC₁(Cr₁), AC
₁(Cr₂), ... Where DC, AC₁,
AC₂, ..., as described with reference to FIG.
Assigned to a set of runs followed by levels
These are respective codes of the generated variable length code.

The converted elementary stream in which the order of the coefficient data is rearranged by the recording side stream converter is supplied to the packing and shuffling section incorporated in the ECC encoder 109. The length of the data of the macroblock is the same in the converted elementary stream and the elementary stream before conversion. Also, MPE
Even if the G encoder 102 has a fixed length in GOP (1 frame) units by bit rate control, the length varies in macro block units. In the packing and shuffling section, macro block data is applied to a fixed frame.

FIG. 22 schematically shows packing processing of macroblocks in the packing and shuffling section. The macroblock is fitted into a fixed frame having a predetermined data length and packed. The data length of the fixed frame used at this time is matched with the data length of the sync block which is the minimum unit of data at the time of recording and reproducing. This is because the shuffling and error correction coding processes are easily performed. In FIG. 22, for simplicity,
Assume that one frame contains 8 macroblocks.

Due to the variable length coding, as shown in FIG. 22A, the lengths of eight macroblocks are different from each other. In this example, the data of macroblock # 1, the data of # 3, and the data of # 6 are longer than the length of the data area of one sync block, which is a fixed frame.
The macroblock # 2 data, # 5 data, # 7 data, and # 8 data are short. The data of the macro block # 4 has a length substantially equal to that of one sync block.

By the packing processing, macroblocks are packed in a fixed length frame having a length of one sync block. Data can be packed without excess or deficiency because the amount of data generated in one frame period is controlled to be a fixed amount. As shown in an example in FIG. 22B, a macro block longer than one sync block is divided at a position corresponding to the sync block length. Of the divided macroblocks, a portion (overflow portion) protruding from the sync block length is packed in an area that is vacant in order from the beginning, that is, after the macroblock whose length is less than the sync block length.

In the example of FIG. 22B, macroblock # 1
First, the part that is out of the sync block length is packed after the macro block # 2, and when it reaches the sync block length, it is packed after the macro block # 5. Next, the part of the macro block # 3 that extends beyond the sync block length is packed behind the macro block # 7. Further, the portion of the macroblock # 6 that extends beyond the sync block length is packed behind the macroblock # 7, and the portion that extends further out of the macroblock # 7.
It is packed behind 8. In this way, each macro block is packed in the fixed frame having the sync block length.

The length of the variable length data corresponding to each macroblock can be checked in advance by the recording side stream converter. As a result, the packing unit can know the end of the macroblock data without decoding the VLC data and inspecting the contents.

FIG. 23 shows the ECC encoder 13 described above.
9 shows a more specific configuration. In FIG. 23, 164
Is an interface of the main memory 160 external to the IC. The main memory 160 is composed of SDRAM. The interface 164 arbitrates requests from the inside to the main memory 160, and performs write / read processing on the main memory 160. In addition, the packing section 137a, the video shuffling section 137b, and the packing section 137c constitute a packing and shuffling section 137.

FIG. 24 shows an example of the address configuration of the main memory 160. The main memory 160 is, for example, 64
It is composed of an M-bit SDRAM. Main memory 16
0 has a video area 250, an overflow area 251, and an audio area 252. Video area 250
Are four banks (vbank # 0, vbank # 1,
vbank # 2 and vbank # 3). Each of the four banks can store a digital video signal in one equal length unit. The 1-equalization unit is a unit for controlling the amount of generated data to a substantially target value, for example, 1 of a video signal
It is a picture (I picture). Part A in FIG. 24
Indicates the data portion of one sync block of the video signal. Data of a different number of bytes is inserted in one sync block depending on the format. In order to support a plurality of formats, the number of bytes which is more than the maximum number and is convenient for processing, for example 256 bytes, is the data size of one sync block.

Each bank of the video area is further divided into a packing area 250A and an output area 250B to the inner coding encoder. Overflow area 251
Corresponds to the above-mentioned video area and is composed of four banks. Further, the main memory 160 has a region 252 for processing audio data.

In the first embodiment, by referring to the data length indicator of each macroblock, the packing unit 137a stores the fixed frame length data and the overflow data which is a portion exceeding the fixed frame in the main memory 160. Store in separate areas. The fixed frame length data is data that is equal to or shorter than the length of the data area of the sync block, and is hereinafter referred to as block length data. The area for storing the block length data is the packing processing area 250 of each bank.
It is A. When the data length is shorter than the block length, an empty area is created in the corresponding area of the main memory 160.
The video shuffling unit 137b performs shuffling by controlling the write address. Here, the video shuffling unit 137b shuffles only the block length data, and the overflow part is written in the area assigned to the overflow data without being shuffled.

Next, the packing unit 137c performs a process of packing the overflow portion in the memory for the outer code encoder 139 and reading it. In other words, 1 prepared from the main memory 160 to the outer code encoder 139
If the block length data is read into the ECC block memory, and if the block length data has a vacant area, the overflow portion is read and the block length is filled with the data. Then, when the data for one ECC block is read, the reading process is temporarily interrupted, and the outer code encoder 139 generates the parity of the outer code. The outer code parity is the outer code encoder 13
9 memory. When the processing of the outer code encoder 139 is completed for one ECC block, the outer code encoder 1
The data and the outer code parity are rearranged from 39 in the order of performing the inner code, and are written back to the packing processing area 250A of the main memory 160 and another output area 250B.
The video shuffling unit 140 performs shuffling in sync block units by controlling the address when writing back the data whose outer code has been encoded to the main memory 160.

In this way, the block length data and the overflow data are divided and the data is written into the first area 250A of the main memory 160 (first packing processing), and the overflow data is packed into the memory of the outer code encoder 139. Read in (second packing process), outer code parity generation, and data and outer code parity in the second area 250 of the main memory 160.
The process of writing back to B is performed in units of one ECC block.
By providing the outer code encoder 139 with a memory of the size of the ECC block, it is possible to reduce the frequency of access to the main memory 160.

Then, a predetermined number of E's included in one picture
When the processing of the CC block (for example, 32 ECC blocks) is completed, the packing of one picture and the encoding of the outer code are completed. Then, the data read from the area 250B of the main memory 160 via the interface 164 is processed by the ID addition unit 148, the inner code encoder 147, and the synchronization addition unit 150, and the parallel-serial conversion unit 124 outputs the output data of the synchronization addition unit 150. Is converted to bit serial data. The output serial data is processed by the partial response class 4 precoder 125. This output is digitally modulated as needed, and is supplied to the rotary head provided on the rotary drum 111 via the recording amplifier 110.

In addition, a sync block called null sync in which effective data is not arranged is introduced in the ECC block, and the EC is adapted to the difference in the format of the recording video signal.
The configuration of the C block is made flexible.
The null sync is generated in the packing unit 137 a of the packing and shuffling block 137 and written in the main memory 160. Therefore, since the null sync has a data recording area, this can be used as a recording sync for the overflow portion.

In the case of audio data, even-numbered samples and odd-numbered samples of audio data of one field form different ECC blocks. Since the ECC outer code sequence is composed of audio samples in the input order, the outer code encoder 136 generates an outer code parity each time an audio sample of the outer code sequence is input. The shuffling unit 137 performs shuffling (channel unit and sync block unit) by address control when writing the output of the outer code encoder 136 into the area 252 of the main memory 160.

Further, a CPU interface indicated by 126 is provided to receive data from an external CPU 127 functioning as a system controller and set parameters for internal blocks. In order to support multiple formats, it is possible to set many parameters such as sync block length and parity length.

The "packing length data" as one of the parameters is sent to the packing units 137a and 137b, and the packing units 137a and 137b determine the fixed frame (the "sync block length" in FIG. 22A) based on this. (Length shown as) with VLC data.

The "pack number data" as one of the parameters is sent to the packing section 137b, and the packing section 137b determines the number of packs per sync block based on this, and the data for the determined number of packs. Are supplied to the outer code encoder 139.

The "video outer code parity number data" as one of the parameters is sent to the outer code encoder 139, and the outer code encoder 139 outputs the outer code of the video data for which the number of parities based on this is output. Encode.

Each of "ID information" and "DID information" as one of the parameters is sent to the ID adding section 148, and the ID adding section 148 receives the ID information and the DID information.
The ID information is added to the data string of unit length read from the main memory 160.

Each of the "video inner code parity number data" and the "audio inner code parity number data" as one of the parameters is an inner code encoder 149.
Then, the inner code encoder 149 encodes the inner code of the video data and the audio data for which the number of parities is generated based on them. It should be noted that "sync length data" which is one of the parameters is also sent to the inner code encoder 149, whereby the unit length (sync length) of the inner coded data is regulated.

Further, shuffling table data as one of the parameters is stored in the video shuffling table (RAM) 128v and the audio shuffling table (RAM) 128a. The shuffling table 128v performs address conversion for shuffling the video shuffling units 137b and 140. The shuffling table 128a performs address conversion for the audio shuffling 137.

Next, the processing in the code amount measuring unit 560 will be described. In the code amount measuring device 530, the code amount can be known by checking the data amount between the start codes corresponding to the division of the equal length unit in the input elementary stream. In the first embodiment of this embodiment,
Since 1 GOP = 1 picture, the code amount of the equal length unit can be known by checking the clock from the GOP header 6 to the next GOP header 6.

As described above, the SDTI receiving section 108, when outputting an elementary stream, enables the enable signal E corresponding to the valid period of the elementary stream.
N is output together. In the code amount measuring device 530, the code amount of the equal length unit is actually checked by the length of the enable signal EN. For example, when the data width is 8 bits (1 byte), the code amount can be known by the number of bytes by checking the number of clocks in the state ("H" state) in which the enable signal EN represents the valid period.

The code amount measurement by the enable signal EN will be described in more detail with reference to FIGS. 25 and 26. Figure 2
5 schematically shows an interface between the SDTI receiver 108 and the recording MFC 106. Figure 26 is SD
6 shows a time chart of an example of a signal exchanged between the TI receiving unit 108 and the recording MFC 106. Note that, in FIG. 25, for the sake of explanation, the code amount measuring unit 560 indicates that the recording side M
It is assumed to be built in the FC 106.

SDTI receiver 108 and recording MFC 10
Between the recording side MFC 106 and the SDTI receiving section 1
A request signal line for sending a request signal RQ to 08,
The SDTI receiving unit 108 is connected to the SDTI receiving unit 108 by an enable signal EN and a bit stream line with an enable signal EN for sending a bit stream. The request signal RQ requests the SDTI receiving unit 108 to output MPEG ES in the “H” state, for example.
It is a signal that requests the output to be stopped in the L ″ state.

As described above, based on the request signal RQ from the recording side MFC 106, the SDTI receiving section 108
To output an MPEG ES and an enable signal EN.

First, a case will be described in which the stream input to the SDTI receiving unit 108 is separated for each frame, and the SDTI receiving unit 108 can determine the frame boundary (frame length). The timing generator 104 generates a frame synchronization signal based on the synchronization signal extracted by the SDTI receiving unit 108 from the MPEG ES input to the input terminal 107. This frame synchronization signal is supplied to the recording MFC 106.

Based on the frame synchronization signal, the recording system MFC
The request signal RQ is transmitted from 106 to the SDTI receiving unit 108. The SDTI receiving unit 108 receives the request signal RQ, and then the SDTI receiving unit 10 receives the request signal RQ.
The enable signal EN is set to the "H" state with a delay of a predetermined clock (for example, 2 clocks) required for the processing in 8 and the bit stream for one frame (MPEG
ES) is output. The bitstream is the recording side MF
It is stored in the buffer of C106 and is simply decoded to detect the rear end of the frame.

For example, in the first embodiment in which 1 picture = 1 GOP, the number of slices after the GOP header 6 and the number of macroblocks included in the last slice are checked to determine the number of slices after the frame. The edge can be detected. Alternatively, the number of macroblocks may be simply checked.

When the end of the frame is detected, the recording side M
The request signal RQ sent from the FC 106 to the SDTI receiving unit 108 is released. In response to this, the MPEG from the SDTI receiving unit 108 is delayed by a predetermined clock.
The output of ES is stopped and the enable signal EN
Is released and the state becomes "L". The code amount measuring unit 560 can know the code amount for one frame, that is, the equal length unit by measuring the number of clocks during the period when the enable signal EN is in the “H” state.

A case where the stream input to the SDTI receiving unit 108 is not separated for each frame will be described. In this case, since the SDTI receiving unit 108 cannot know the frame boundary, MPEG ES
Recording side MF is output continuously regardless of the frame
It is stored in the buffer of C106. In the first frame, the recording side MFC 106 decodes the MPEG ES stored in the buffer, and when the trailing end of the frame is detected, the request signal RQ is set to the “L” state for the SDTI receiving unit 108, and the MPEG Output stop of ES is required.

In response to this request, the SDTI receiving unit 108
Then, as described above, the actual stream output is stopped with a delay of the predetermined clock. Therefore, the recording side MF
In C106, the stream of the next frame is input before the stream stored in the buffer is completely processed and the stream is not swept out from the buffer.

That is, in the recording side MFC 106,
When the trailing end of the frame initially stored in the buffer is detected, a request signal RQ requesting the stop of the output of the stream is sent to the SDTI receiving unit 108, and the stream of the frame is swept from the buffer. Be done. The stream of the next frame, which is supplied until the output of the stream is stopped by the transmitted request signal RQ, is accumulated in the buffer.

The recording side MFC 106 sends a request signal R to the SDTI receiving section 108 based on the frame synchronization signal.
Q is sent to request the stream for the next frame. By this request, the continuous stream of the part interrupted by the stream output stop by the previous request signal RQ is SD.
It is output from the TI reception unit 108 and stored in the buffer of the recording MFC 106. The recording-side MFC 106 processes the stream stored in the buffer by the previous request and the stream stored in the buffer by the current request, and detects the trailing end of the frame.

When the trailing edge of the frame is detected, the recording side MFC 106 to the SDTI receiving section 108 are processed in the same manner as described above.
, A request signal RQ requesting to stop the stream output is sent. In the SDTI receiving unit 108, similarly, stream output is stopped after a predetermined clock delay,
The buffer of the recording MFC 106 stores the stream of the next frame for a predetermined number of clocks. This process is repeated until the stream input to the SDTI receiving unit 108 is completed.

The enable signal EN is transmitted with the bitstream and indicates the valid period of the bitstream.
By repeating the process as described above, the period during which the enable signal EN is in the “H” state is substantially SD.
It is equal to one frame period of the stream output from the TI receiving unit 108. Therefore, the code amount measuring unit 560
By measuring the length of the enable signal EN, the amount of code for one frame, that is, the unit length equalization unit can be known.

However, in this case, in the first frame of the stream supplied to the SDTI receiving unit 108, the enable signal EN is equal to one frame and a predetermined clock
It becomes longer, and becomes shorter by a predetermined clock in the final frame.

The method of measuring the code amount in equal length units is as follows:
The method is not limited to the above. For example, by detecting each header of MPEG ES, sequence_header_
code, group_of_pictures_st
art_code or picture_start_
From code, sequence_end of the next frame
The length up to _code may be measured. Similarly, sequence_header_code, g
group_of_pictures_start_co
From de or picture_start_code, the sequence_header_c of the next frame
ode, group_of_pictures_sta
rt_code or picture_start_c
You can also measure the length to the ode. In these methods, since the header information is a unit in which each byte is aligned (see FIG. 16A), it is not necessary to decode the variable length code. It suffices to have a pattern matching means for detecting each start_code and a counter for measuring a clock.

In addition, stuffing may be removed when a stream is input. In this case, the deleted stuffing is not measured and only the effective amount of recorded information is extracted. That is, only the code amount to be recorded is measured.

It is conceivable to extract the parameter of the sequence header 2 from the stream and check the bit_rate_value, but bit_rate_value
Is not preferable because it does not specify the code amount in units of pictures or GOPs and the bit rate also includes the above-mentioned stuffing.

Next, a second embodiment of the present invention will be described. In the second embodiment, a frame in which the code amount of the equal length unit exceeds the specified amount is replaced with a frame having a small code amount such as black display or gray display. At this time, picture_coding_type in the picture header 9 is set to a value indicating the I picture, and mac in the macroblock header 14 is set.
Change the block_type to a value indicating “Intra”. Furthermore, in all macroblocks of the frame, the DC component is set to a value representing black or gray, and the AC component is set to 0.

As described above, by replacing a frame in which the code amount exceeds the code amount defined in the equal length unit with another predetermined frame, a syntax error is avoided and the tape format is observed. ,
The continuity of the stream can be maintained.

A frame in which the code amount exceeds the code amount defined in the equal length unit is replaced with a frame displaying black or gray because these are image patterns having the smallest code amount. That is, it is conceivable that the number of frames in a frame displaying a single achromatic image having no color information is small. Other image patterns can be used as long as the code amount of the equal-length unit is smaller than the total code amount defined for the equal-length unit.

FIG. 27 shows V according to the second embodiment of the present invention.
The basic structure of TR is shown. Note that, in FIG. 27, portions common to those in FIG. 3 described above are denoted by the same reference numerals, and detailed description thereof will be omitted. In the configuration of FIG. 27, a stream generator 532 and a switch circuit 533 are added in the code amount measuring unit 560 to the configuration of FIG. 3 described above.

The stream generator 532 generates and outputs a stream in which black is displayed, for example.
The switch circuit 533 switches the output of the memory 531 and the stream generator 532 based on the measurement result of the code amount measuring device 530 and supplies the output to the ECC encoder 514. The stream input from the terminal 512 is stored in the memory 5
While being stored in 31, the code amount is supplied to the code amount measuring device 530, and the code amount of the equal length unit is measured as in the first embodiment described above. The memory 531 is the memory 53.
The stream stored in 1 is controlled so as not to be output until the code amount measuring unit 530 finishes measuring the code amount of the corresponding stream.

If the measured code amount does not exceed the specified value, the switch circuit 533 selects the memory 531 side, and the stream stored in the memory 531 is read. The stream read from the memory 531 is supplied to the ECC encoder 514 via the switch circuit 533 and the switch circuit 513.

On the other hand, if the code amount measured by the code amount measuring device 530 exceeds the specified value, the switch circuit 533 selects the stream generator 532 side, and the stream of black or gray generated by the stream generator 532. Through the switch circuit 533 and the switch circuit 513.
It is supplied to the CC encoder 514.

The stream generator 532 has, for example, a memory, and the data of the macro block or DCT block representing black and each header information are stored in this memory in advance. By sequentially reading the data stored in this memory according to the clock, the stream generator 532
Can output a stream representing black. Not limited to this, data may be sequentially output according to a predetermined procedure, and a stream representing black may be output.

Next, a third embodiment of the present invention will be described. In the third embodiment of the present invention, a frame in which the code amount of the equal length unit exceeds a prescribed amount is processed by, for example, MPEG.
2 is replaced with a P picture frame for forward reference. In the stream of frames in which the code amount of the equal length unit exceeds the specified amount, the pict of the picture header 9
The ure_coding_type is changed to a P picture, and all macroblocks are forward reference difference = 0, that is, MC (Motion Compensation) = 0 and MV (MotionVecto).
r) = 0 and Not Coded.

As described above, by replacing a frame in which the code amount exceeds the code amount defined in the equal length unit with the frame for forward reference, the syntax error is avoided and the stream is maintained while observing the tape format. The continuity of can be maintained. Further, since the image formed by the replaced frame is formed by performing the forward reference, it does not significantly differ from the original image.

In the third embodiment of the present invention, as shown in FIG.
The configuration of the second embodiment of No. 7 can be applied as it is. Here, the stream generator 532 has a memory, and in this memory, the picture_coding_type of the picture header 9 described above is set to a value indicating a P picture, and all macroblocks are forward-referenced = 0.
A frame stream having a value indicating is stored in advance.

The stream input from the terminal 512 is
The code amount measuring device 53 is stored in the memory 531.
0, and the code amount of the equal length unit is measured as in the first embodiment described above. The memory 531 is controlled so that the stream stored in the memory 531 is not output until the code amount measuring unit 530 finishes measuring the code amount of the corresponding stream.

If the measured code amount does not exceed the specified value, the switch circuit 533 selects the memory 531 side, the stream stored in the memory 531 is read, and the switch circuit 533 and the switch circuit 513 are read.
Is supplied to the ECC encoder 514 via. on the other hand,
If the code amount measured by the code amount measuring device 530 exceeds the specified value, the switch circuit 533 causes the stream generator 53 to operate.
The second side is selected, and the P-picture stream generated by the stream generator 532 is supplied to the ECC encoder 514 via the switch circuit 533 and the switch circuit 513.

The third form of this embodiment is pict.
It cannot be applied to a device that allows only I pictures as ure_coding_type.

Next, a fourth embodiment of the invention will be described. In the fourth embodiment of the present invention, it is already confirmed that the code amount of the equal length unit does not exceed the specified value in the frame in which the code amount of the equal length unit exceeds the specified amount. Is also replaced with the stream of the frame that is previous in time.

FIG. 28 shows V according to the fourth embodiment.
The basic structure of TR is shown. 28, the same parts as those in FIG. 3 described above are designated by the same reference numerals, and detailed description thereof will be omitted. In the configuration of FIG. 28, a memory 540 and a switch circuit 541 are added in the code amount measuring unit 560 to the configuration of FIG. 3 described above.

The stream input from the terminal 512 is
The code amount measuring device 53 is stored in the memory 531.
0, and the code amount of the equal length unit is measured as in the first embodiment described above. The memory 531 is controlled so that the stream stored in the memory 531 is not output until the code amount measuring unit 530 finishes measuring the code amount of the corresponding stream.

As a result of the measurement by the code amount measuring device 530, if the code amount in the equal length unit does not exceed the specified value,
The corresponding stream is read from the memory 531 and stored in the memory 540. At the same time, the memory 531 side is selected by the switch circuit 541, and the stream read from the memory 531 is supplied to the ECC encoder 514 via the switch circuit 533 and the switch circuit 513.

On the other hand, if the code amount measured by the code amount measuring device 530 exceeds the specified value, the switch circuit 533 selects the memory 540 side, and the stream of the past frame (previous frame) stored in the memory 540 is selected. Is read and supplied to the ECC encoder 514 via the switch circuit 540 and the switch circuit 513.

According to the fourth embodiment, as a result of the measurement, the memory 540 is updated on a frame-by-frame basis in the stream in which the code amount in the equal length unit does not exceed the specified value. Then, the stream in which the code amount exceeds the code amount defined in the equal length unit is replaced with the stream stored in the memory 540. By doing so, it is possible to avoid syntax errors and maintain the continuity of the stream while complying with the tape format. Furthermore, since the frame of the stream whose code amount exceeds the code amount defined in the equal length unit is replaced with the closest past frame, the formed image does not differ greatly from the original image.

Next explained is the fifth embodiment of the invention. In the fifth embodiment, the higher-order component of the DCT coefficient of each macroblock is deleted from the frame in which the code amount of the equal length unit exceeds the specified amount. Thereby, the code amount of the frame can be suppressed to be equal to or less than the specified value of the equal length unit.

FIG. 29 shows V according to the fifth embodiment.
The basic structure of TR is shown. 29, the same parts as those in FIG. 3 described above are designated by the same reference numerals, and detailed description thereof will be omitted. In the configuration of FIG. 29, a low pass filter (LPF) 550 and a switch circuit 551 are added in the code amount measuring unit 560 to the configuration of FIG. 3 described above. The LPF 550 deletes high-order components of the DCT coefficient in a predetermined manner.

The stream input from the terminal 512 is
The code amount measuring device 53 is stored in the memory 531.
0, and the code amount of the equal length unit is measured as in the first embodiment described above. The memory 531 is controlled so that the stream stored in the memory 531 is not output until the code amount measuring unit 530 finishes measuring the code amount of the corresponding stream.

As a result of the measurement by the code amount measuring device 530, if the code amount of the equal length unit does not exceed the specified value,
The memory 531 side is selected by the switch circuit 551, and the stream read from the memory 531 is switched to the switch circuit 5
It is supplied to the ECC encoder 514 via the switch 51 and the switch circuit 513.

On the other hand, if the code amount measured by the code amount measuring device 530 exceeds the specified value, the switch circuit 551 outputs L.
The PF550 side is selected. The MPEG ES read from the memory 531 is supplied to the LPF 550, and the DCT
Higher-order components of the coefficient are deleted in a predetermined manner, and the code amount of the equal length unit is suppressed to a specified value or less. The MPEG ES output from the LPF 550 is supplied to the ECC encoder 514 via the switch circuit 551 and the switch circuit 513.

The following two methods can be considered as the method of deleting the higher-order component of the DCT coefficient in the LPF 550 described above. (1) For all macroblocks in a frame, all DCT coefficients of a predetermined degree or higher are deleted. That is, DCT
The frequency is limited by the coefficient. (2) In principle, all the highest-order DCT coefficients are deleted for all macroblocks in the frame. At this time,
DCT coefficients of a predetermined order or less are not deleted.

In the method (2) of deleting all the highest-order DCT coefficients, the DCT coefficients of a predetermined order or less are protected in order to protect an image with few frequency components such as a flat image. Is.

FIG. 30 shows an example of the configuration of the LPF 550. FIG. 30A shows an example of the configuration in which the variable length code of the input stream is decoded and the high-order component of the DCT coefficient is deleted. In FIG. 30A, the input MPEG ES
Variable length code is decoded by the variable length code decoder 555, and D
The CT coefficient is extracted. With respect to the extracted DCT coefficients, the processing of deleting all the DCT coefficients of the above-mentioned predetermined order of (1) or deleting all the DCT coefficients of the highest order while leaving the coefficients of the predetermined order or less of (2). Is performed, and the higher-order component of the DCT coefficient is deleted. DCT
The stream from which the higher-order components of the coefficients have been deleted is supplied to the variable-length code encoder 556, variable-length coded, and MPE.
It is output as G ES.

FIG. 30B shows an example of the structure in which the variable length code of the input stream is decomposed and the higher order components of the DCT coefficient are deleted. The input variable length code of MPEG ES is decomposed into a code word by the variable length code decomposer 557, and the code and the code length are output. Based on this code and code length,
DCT coefficient higher than a predetermined order, or highest order DC
The positions of the T coefficient and the coefficient of a predetermined degree or less are discriminated, and they are deleted. And (1) DC of a predetermined order or more
The stream in which the T coefficient or (2) the coefficient of the predetermined degree or less is left and the DCT coefficient of the highest degree is deleted is supplied to the variable length code connector 558, the variable length code is reconnected, and MPEG ES is obtained. Is output.

Here, the DCT coefficient can be deleted by using the memory. For example, taking the configuration of FIG. 30A as an example, the output decoded by the variable length code decoder 555 is expanded on the memory. Then, when data is read from this memory by the variable-length code encoder 556, a predetermined address control is performed to read DCT coefficients other than the order to be deleted. The read DCT coefficient is supplied to the variable-length code encoder 556 and variable-length coded into MPEG ES. This processing using the memory can be similarly applied to the configuration of FIG. 30B.

The structure and operation of the LPF 550 described with reference to FIGS. 30A and 30B are the same as those of the recording side MFC 106.
Can be realized by controlling.

According to the fifth embodiment, it is necessary to decode or decompose a variable length code and re-encode or connect it, but information is uniformly omitted from the entire screen. , No distortion occurs at a specific part of the screen.

In the above, the case where the present invention is applied to the stream compressed and encoded by the MPEG system has been described, but this is not limited to this example. For example JPEG
The present invention can be widely applied to devices such as (Joint Photographic Experts Group) to which a stream compressed and encoded by another method is input.

Further, in the above, the present invention is based on MPEG E
Although it has been described that the present invention is applied to a recording / reproducing apparatus that records S on a recording medium, this is not limited to this example. INDUSTRIAL APPLICABILITY The present invention can be widely applied not only to the recording / reproducing apparatus but also to video and audio equipment that handles a compression-coded stream.

Furthermore, in the above description, the recording medium is described as a magnetic tape, but this is not limited to this example. For example, the present invention can be applied to a disc-shaped recording medium such as an MO (Magneto-Optical) disc. Further, not limited to this, as long as it is a recording device for recording a stream encoded by a variable length code on a recording medium with a code amount defined by an equal length unit, for example, a disk recorder or a RAM (Random Access Memory) recorder. It can also be applied to recording devices using other recording media such as

Furthermore, in the above description, the case where the present invention is applied to a recording / reproducing apparatus that handles a stream in which a video signal is compression-encoded has been described, but this is not limited to this example. For example, AC-3 (Audio Code Number)
3), AAC (Advanced Audio Coding), dts (Digital
Theater Systems), ATRAC (Adaptive Transform Ac
The principle of the present invention can be applied to an acoustic recording device using a voice compression technique such as oustic coding.

Further, in the above, the input MPEG E
When the code amount of the equal length unit in S exceeds the specified value, recording is stopped, stream is replaced, or DCT is performed.
Although it has been described that the coefficient is deleted, this is not limited to this example. For example, the input MPEG
Even if the code amount of the equal length unit in ES exceeds the specified value, it is recorded on the recording medium as it is, and at that time, the fact is recorded on a predetermined area of the recording medium, for example, a system area. good. In this case, when reproducing this recording medium, the reproducing device performs a predetermined process on the stream of the equal length unit whose code amount exceeds the specified value.

Further, in the case where the encoder cannot equalize the length when encoding the baseband signal, by applying the present invention, it is possible to remedy the insufficient capacity of the encoder.

[0205]

As described above, according to the present invention, when a stream encoded using a variable length code is equalized in a predetermined unit and recorded on a recording medium, the input stream is equalized. The code amount of a unit is measured, and when the measured code amount is equal to or more than a predetermined amount, it can be dealt with.
Therefore, even if a stream that exceeds the specified bit rate is input, the recording circuit fails, the recording medium fails, that is, the recording format on the recording medium fails, the image is seriously disturbed in the reproduced image, and an unauthorized recording medium is created. It is effective in preventing such troubles.

Further, in the case where the encoder cannot equalize the length when encoding the baseband signal, by applying the present invention, it is possible to remedy the lack of the capability of the encoder.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of a VTR that records and reproduces a baseband signal using a magnetic tape as a recording medium.

FIG. 2 is a block diagram showing a basic configuration of a VTR that records and reproduces a stream in which a video signal is encoded by the MPEG2 system.

FIG. 3 is a block diagram showing a basic configuration of a VTR according to the first embodiment of the present invention.

FIG. 4 is a schematic diagram schematically showing a hierarchical structure of MPEG2 data.

FIG. 5 is a schematic diagram showing the contents and bit allocation of data arranged in an MPEG2 stream.

FIG. 6 is a schematic diagram showing the content and bit allocation of data arranged in an MPEG2 stream.

FIG. 7 is a schematic diagram showing the content and bit allocation of data arranged in an MPEG2 stream.

FIG. 8 is a schematic diagram showing the contents and bit allocation of data arranged in an MPEG2 stream.

FIG. 9 is a schematic diagram showing the content and bit allocation of data arranged in an MPEG2 stream.

FIG. 10 is a schematic diagram showing the content and bit allocation of data arranged in an MPEG2 stream.

FIG. 11 is a schematic diagram showing the content and bit allocation of data arranged in an MPEG2 stream.

FIG. 12 is a schematic diagram showing the content and bit allocation of data arranged in an MPEG2 stream.

FIG. 13 is a schematic diagram showing the content and bit allocation of data arranged in an MPEG2 stream.

FIG. 14 is a schematic diagram showing the content and bit allocation of data arranged in an MPEG2 stream.

FIG. 15 is a schematic diagram showing the content and bit allocation of data arranged in an MPEG2 stream.

FIG. 16 is a diagram for explaining alignment of data in units of bytes.

FIG. 17 is a schematic diagram specifically showing a header of an MPEG stream.

FIG. 18 is a block diagram showing an example of a configuration of a recording / reproducing apparatus applicable to the present invention.

FIG. 19 is a schematic diagram showing an example of a track format formed on a magnetic tape.

[Fig. 20] Fig. 20 is a schematic diagram for explaining a method of outputting a video encoder and variable length coding.

FIG. 21 is a schematic diagram for explaining rearrangement of the output order of the video encoder.

FIG. 22 is a schematic diagram for explaining a process of packing the data in which the order is rearranged in a sync block.

FIG. 23 is a block diagram showing a more specific configuration of the ECC encoder.

FIG. 24 is a schematic diagram showing an example of an address configuration of a main memory.

FIG. 25 is a block diagram schematically showing an interface between an SDTI receiver and a recording MFC.

FIG. 26 is a time chart showing an example of signals exchanged between the SDTI receiver and the recording MFC.

FIG. 27 is a block diagram showing a basic structure of a VTR according to second and third embodiments of the present invention.

FIG. 28 is a block diagram showing a basic structure of a VTR according to a fourth embodiment of the present invention.

FIG. 29 is a block diagram showing a basic structure of a VTR according to a fifth embodiment of the present invention.

FIG. 30 is a block diagram showing an example of the configuration of an LPF.

[Explanation of symbols]

1 ... Sequence header code, 2 ... Sequence header, 3 ... Sequence extension, 4 ... Extension and user data, 5 ... GOP start code, 6 ...
GOP header, 7 ... user data, 8 ... picture start code, 9 ... picture header, 10 ...
..Picture coding extension, 11 ... Extension and user data, 12 ... Slice start code, 13 ...
・ Slice header, 14 ... Macroblock header,
101 ... SDI receiver, 102 ... MPEG encoder, 106 ... Recording side multi-format converter (MFC), 108 ... SDTI receiver, 109
... ECC encoder, 112 ... Magnetic tape, 1
13 ... ECC decoder, 114 ... Playback side MF
C, 115 ... SDTI output section, 116 ... MPE
G decoder, 118 ... SDI output section, 137a, 1
37c ... Packing unit, 137b ... Video shuffling unit, 139 ... Outer code encoder, 140 ...
..Video shuffling, 149 ... Inner code encoder, 530 ... Code amount measuring device, 531, 540 ...
Memory, 532 ... Stream generator, 550 ...
LPF, 560 ... Code amount measuring unit

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 7/24 H04N 7/13 Z (72) Inventor Akira Sugiyama 6-735 Kitashinagawa, Shinagawa-ku, Tokyo No. Sony Corporation (72) Inventor Hideyuki Matsumoto 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo F-terms at Sony Corporation (reference) 5C018 HA01 HA09 HA13 5C053 FA20 FA21 GA11 GB06 GB15 GB38 KA16 LA06 5C059 KK35 MA00 MA23 ME01 RF05 SS11 TA71 TC18 TD07 TD12 UA02 UA34 5D044 AB07 BC01 CC03 EF03 GK08 GK12 HH02 HH13

Claims (9)

[Claims] 1. A recording device for recording a stream coded using a variable length code on a recording medium in a predetermined equal length unit, wherein an input means to which the stream coded using the variable length code is input. A recording unit for recording the stream input to the input unit on a recording medium in a predetermined equalization unit; and a code amount of the stream input to the input unit in the predetermined equalization unit. Based on the measurement means for measuring and the measurement result of the measurement means, the code amount of the predetermined equalization unit of the input stream is the total code amount specified for the predetermined equalization unit. A recording device, comprising: a control unit that controls an excess stream so as not to be recorded on the recording medium. 2. The recording apparatus according to claim 1, wherein the control unit controls the recording unit to stop the recording. 3. The recording apparatus according to claim 1, wherein the control means outputs a stream of the predetermined equalization unit that exceeds the prescribed total code amount for the predetermined equalization unit. A recording apparatus, which is controlled so that the code amount of the predetermined equal length unit is replaced with another stream whose code amount is within the specified code total amount. 4. The recording device according to claim 3, further comprising stream output means for outputting the stream of the predetermined equal length unit for displaying a screen having a single achromatic color, and the other stream. Is a stream of the predetermined equal length unit output from the stream output means. 5. The recording apparatus according to claim 3, wherein, when recording the input stream on the recording medium based on the measurement result of the measuring means, the predetermined equal-length unit is used for the predetermined equal length unit. The storage device further includes a storage unit that stores a stream of the predetermined equalization unit that does not exceed the defined total code amount, and the other stream is a stream of the predetermined equalization unit stored in the storage unit. A recording device characterized by being. 6. The recording apparatus according to claim 1, wherein the control unit is configured to control the predetermined equalization unit of the predetermined equalization unit that exceeds the total code amount of the predetermined predetermined equalization unit. A recording apparatus which controls a stream so as to delete a high-order component of a DCT coefficient for each macroblock of the stream. 7. The recording apparatus according to claim 6, wherein the DCT coefficients of a predetermined degree or more of each macroblock are deleted. 8. The recording apparatus according to claim 6, wherein each macroblock is not less than a predetermined degree, and
A recording apparatus, wherein all the DCT coefficients of the highest order are deleted. 9. A recording method for recording a stream coded using a variable length code on a recording medium in a predetermined equal length unit, wherein an input of a stream coded using the variable length code is input. A recording step of recording the stream input in the input step in a predetermined equalization unit on a recording medium; and a predetermined equalization unit of the stream input in the input step. Based on the measurement step of measuring the code amount of, and the measurement result of the measurement step, the code amount of the predetermined equalization unit of the input stream is And a control step of controlling so as not to record the stream exceeding the specified code total amount on the recording medium.