JP2000244863A - Recording device and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide recording and reproducing devices which can obtain stable special reproduction images in a special reproduction mode in a simple process and without performing time management for every double speed reproduction. SOLUTION: An ordinary reproduction recording data generation part 1 generates the recording data for ordinary reproduction from a bit stream 201, and a special reproduction recording data generation part 2 generates the recording data for special reproduction from the stream 201. A packet generation part 3 generates a time information packet which shows the time information to perform the output time management of reproduced images and also a control information packet which shows the control information to decode the recorded data for special reproduction. These packets are outputted to a special reproduction recording data generation part 2 so that the time and control information are recorded at each prescribed position in a special reproduction area. A recording part 5 records the ordinary and special reproduction recording data in each prescribed area of a recording medium 202 via a recording head 6.

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 a reproducing apparatus, and more particularly, to a recording apparatus and a reproducing apparatus comprising a video signal and an audio signal which are encoded by utilizing a correlation between screens such as digital satellite broadcasting. The present invention relates to a recording device that digitally records a bit stream to be able to perform special reproduction (variable speed reproduction) and a reproduction device that performs digital reproduction.

[0002]

2. Description of the Related Art In recent years, MPEG (Moving Picture Exper
Digital satellite broadcasting using the ts Group) system has been put to practical use and is attracting attention. The MPEG system is a motion-compensated prediction coding system using correlation between screens, and a plurality of frames constitute a GOP (Group Of Pictures). G
OP is an I picture (I frame and I field)
(Intra-frame coded image), P picture (inter-frame forward prediction coded image), and B picture (bi-directional predicted coded image). For example, IBBPBBPBBPB
When a GOP is composed of 12 pictures such as B, a P picture is predictively coded from an I picture or a P picture three pictures before, and a B picture is bidirectionally coded from a preceding or succeeding I or P picture. Image. In particular, in the MPEG2 system, coded data such as images and sounds is called an elementary stream, and this elementary stream is a PES (Pack
etized Elementary Stream) packet. The PES packet has a structure in which a PES header, which is a data part, follows a PES header.

In the above-mentioned digital satellite broadcasting, a multiplexing method generally called a transport stream is used. In the transport stream, data such as video and audio is divided and transmitted in a 188-byte fixed-length transmission unit called a transport packet. In such a transport stream, PAT (P
rogram Association Table) and PMT (Program Map)
Information for identifying a PID (Packet ID) or the like called a “Table”) (these are collectively referred to as PSI (ProgramSpecific).
Information)). The receiving device extracts the PMT of the specific program by detecting the PAT, detects the packet containing the target image or audio data by examining the PMT, and decodes the encoded data accurately.

When data encoded by the MPEG2 system is recorded / reproduced on a magnetic tape by a digital VTR, the original image can be accurately reproduced in normal reproduction since the data is reproduced in the order of recording. It is.
However, at the time of special reproduction such as a high-speed search, the head traces across the magnetic tape, so that the head traces only a part of each track and cannot reproduce image data accurately.

[0005] For this reason, for example, Japanese Patent Laid-Open No. 6-29212
In Japanese Patent Publication No. 3 (hereinafter referred to as a conventional document), an I picture for special reproduction is recorded at a predetermined position on a recording medium that can be reproduced during special reproduction, and the data is reproduced during special reproduction to reproduce a reproduction screen. Is disclosed. FIG. 18 is a diagram illustrating a conventional technique described in the above-mentioned conventional literature. As shown in FIG. 18, data for special reproduction is recorded in a special reproduction area 501 (shown by oblique lines in FIG. 18) at the center of the recording track on the magnetic tape 202. A dotted line 502 indicates a trace trajectory of the magnetic head when the magnetic tape 202 is fast-forwarded at four times the speed of the normal reproduction. At the time of this quadruple speed reproduction, the magnetic head reproduces the special reproduction area 501 almost on track, so that the special reproduction data can be stably obtained, and the reproduced image at the time of quadruple speed reproduction can be stabilized. Similarly, by stably recording image data for other reproduction speeds at a position at which reproduction can be performed at each reproduction speed, a stable reproduced image can be obtained even at other reproduction speeds.

[0006]

However, using a recording / reproducing apparatus as described in the above-mentioned conventional literature,
When the transport stream is recorded on a recording medium such as a magnetic tape, and when the data for special reproduction is to be recorded in a different area from the data for normal reproduction, an I / O for the special reproduction is performed from the input transport stream. A picture stream is formed by extracting pictures, and P information which is control information for decoding recording data for special reproduction is used.
It is necessary to generate and record a transport stream for special reproduction by multiplexing PSI such as AT and PMT. In particular, the special reproduction area for recording the recording data for special reproduction does not have a recording capacity enough to record the data of all the I pictures to be extracted in real time. Without recording, data of several I-pictures are thinned out and recorded. Further, the time for recording the data of one I-picture in the special reproduction area on the recording medium requires a longer time than the time interval for inputting the I-picture.

Therefore, a PCR (Program Clock Reference) and PTS added to an input bit stream
(Presentation Time Stamp), DTS (Decoding Time S
If you record and play back the time information as it is,
At the time of special reproduction, a problem occurs at a timing of outputting an image, and there is a problem that a reproduced image is disturbed. Also,
Even when the time interval for multiplexing the PSI, which is the control information, and the timing for multiplexing are not considered, there is a problem that the reproduced image is disturbed when the time interval for obtaining the PSI is large.

On the other hand, for each double-speed reproduction, a method of monitoring the transmission packet interval at the time of recording can be considered.
In the case of such a method, a dedicated circuit for performing time management for each double-speed reproduction is required, and the circuit scale of the recording apparatus is increased. Also, changing the time information during playback is
There is also a problem that the circuit scale becomes large in configuring the reproducing apparatus.

Therefore, an object of the present invention is to provide a recording apparatus and a reproducing apparatus capable of obtaining a stable specially reproduced image at the time of special reproduction by simple processing without performing time management for each double-speed reproduction. That is.

[0010]

According to a first aspect of the present invention, a bit stream composed of a video signal and an audio signal encoded by utilizing the correlation between screens is digitally recorded on a recording medium. A recording device for recording, from the input bit stream, a recording data for normal reproduction used to perform normal reproduction composed of a plurality of predetermined recording blocks, a recording data generation unit for normal reproduction, The special reproduction recording data used for performing reproduction (hereinafter, referred to as special reproduction) at a different speed from the normal reproduction composed of a plurality of predetermined recording blocks from the input bit stream is transmitted to the packet generation unit. Means for generating recording data for special reproduction that generates by adding information output by
Generate a time information packet indicating time information for performing output time management of a reproduced image and a control information packet indicating control information for decoding recording data for special reproduction,
Packet generating means for outputting to the recording data generating means for special reproduction, and recording data for normal reproduction recorded in a normal reproducing area formed on the recording medium via a recording head, and special recording data recorded on the recording medium. Recording means for recording recording data for special reproduction in the reproduction area, and a time information packet and a control information packet output from the packet generation means are recorded at a predetermined position in the special reproduction area in the form of recording data for special reproduction. It is characterized by recording.

As described above, according to the first aspect, the time information and the control information generated by the packet generating means are regularly and regularly stored in a predetermined position in the special reproduction area formed on the recording medium. Record. Therefore, the generation of the time information can be realized by a small-scale circuit. Further, it is not necessary to generate time information and control information at the time of special reproduction, so that the circuit scale of the reproduction apparatus can be reduced, which is convenient for configuring a reproduction-only apparatus.

A second invention is an invention according to the first invention, wherein the predetermined position is synchronized with the scanning of the recording head at the time of special reproduction at a predetermined speed, and is performed at least once within a predetermined time interval. It is provided on a recording medium so as to be arranged.

As described above, according to the second aspect, the first aspect
In the invention, the time information and the control information generated by the packet generating means are regularly and regularly recorded in a predetermined position in a special reproduction area formed on a recording medium in synchronization with scanning of a recording head. Therefore, it is not necessary to individually monitor the packet transmission intervals required for each special reproduction, and the generation of time information can be realized by a small-scale circuit. Further, it is not necessary to generate time information and control information at the time of special reproduction, so that the circuit scale of the reproduction apparatus can be reduced, which is convenient for configuring a reproduction-only apparatus.

A third invention is an invention according to the first and second inventions, wherein the packet generating means generates time information indicating a time reference value within a predetermined time interval and records the time information. The time reference value is calculated by adding a predetermined fixed value corresponding to a predetermined position in the special reproduction area to the previous time information.

As described above, according to the third aspect, the first aspect
And the second invention eliminates the need to individually monitor packet transmission intervals required for each special reproduction,
The generation of time information, which was complicated in the past, can be generated by a simple operation of adding a fixed value according to the recording position of the special reproduction area, and the generation of time information can be realized with a small circuit. Becomes possible. Further, it is not necessary to generate time information and control information at the time of special reproduction, and the circuit size of the reproduction apparatus can be reduced, which is convenient for forming a reproduction-only apparatus.

A fourth invention is an invention according to the first to third inventions, wherein the time information for managing the output time of the reproduced image includes a time reference value serving as a reference of the time information;
The time information is obtained from the data amount of the special reproduction image data extracted from the input bit stream, and the time information is a value after the time reference value at which the last data of the special reproduction image data is output, and It is characterized in that the value is normalized based on the frame update cycle of the video display device that displays the image data for special reproduction.

As described above, according to the fourth aspect, the first aspect
In the third to third aspects, the time information is normalized by the frame update cycle of the video display device, so that the decoded image is always output from the beginning of the image, so that the next image is output in the middle of the image. A good image that is not updated to an image can be obtained.

A fifth invention is an invention according to the first to fourth inventions, wherein the time information to be added to the recording data for trick play is a time interval inputted at the time of recording the trick play stream at the time of trick play. The time stamp value is necessary to output the data on the recording medium. It is a fixed value corresponding to the trick play sync block number to be reproduced.

As described above, according to the fifth aspect, the first aspect
In the fourth to fourth aspects, a time stamp value to be added to the recording data for special reproduction is generated from a sync block number for special reproduction by a simple calculation. As a result, it is possible to reduce the circuit scale for adding a time stamp, as compared with the related art.

A sixth invention is a invention according to the first to fifth inventions, and decodes a bit stream composed of an encoded video signal and audio signal using correlation between screens. The control information necessary to perform the special reproduction for the special reproduction recorded in the special reproduction area formed on the recording medium indicates the configuration of the bit stream and the identification number for identifying the content of the data constituting the bit stream. Is dependent on the control information included in the input bit stream, and is information indicating only an identification number corresponding to data extracted from the bit stream to generate recording data for special reproduction. And

As described above, according to the sixth aspect, the first aspect
In the fifth to fifth aspects, the control information indicates only an identification number corresponding to the data extracted for special reproduction, and the unnecessary information is deleted from the information. Can be prevented from malfunctioning, and a more stable special reproduction image can be reproduced.

A seventh invention is the invention according to the first to sixth inventions, wherein the trick play recording data generating means converts the trick play image data extracted from the bit stream into one.
The special reproduction recording data for fast-forward reproduction is generated by reading the special reproduction image data stored in the two memories in order, and reading out the special reproduction image data stored in the memory from the front (in the same direction as the storage order). By reading out the special reproduction image data from the rear (in a direction opposite to the storage order), special reproduction recording data for rewind reproduction is generated.

As described above, according to the seventh aspect, the first aspect
In the sixth to sixth inventions, image data for special reproduction is stored in one memory in a predetermined order, and the data reading direction (order) is different between when fast-forward reproduction data is generated and when rewind reproduction data is generated. Thus, special playback recording data for fast forward playback and rewind playback are generated respectively. As a result, it is not necessary to have a memory for generating data for fast-forward reproduction and data for rewind reproduction, respectively, and the memory capacity can be reduced by half.

An eighth invention is an invention according to the seventh invention, wherein the packet generating means further generates a Null packet which is invalid data in the MPEG standard,
The special reproduction recording data generating means generates special reproduction recording data for fast forward reproduction and rewind reproduction from the special reproduction image data stored in one memory.
When each of the special recording data to be generated is less than a predetermined data amount, a null packet output by the packet generation means is inserted into the special reproduction recording data in order to compensate for the insufficient data. Is satisfied.

As described above, according to the eighth aspect, the seventh aspect
In the invention of the first aspect, by stuffing the special reproduction area with the Null packet, it is possible to prevent an area where data is not recorded in the special reproduction area from being generated.

A ninth invention is an invention according to the seventh invention, wherein the recording data generating means for special reproduction uses the special reproduction image data stored in one memory for fast-forward reproduction and rewind reproduction. When the special reproduction recording data to be generated is less than a predetermined data amount when generating the special reproduction recording data, the data is invalid data in the D-VHS standard in order to compensate for the insufficient data. It is characterized in that a special reproduction area is filled by inserting a dummy sync block into recording data for special reproduction.

As described above, according to the ninth aspect, the seventh aspect
In the present invention, by stuffing the special reproduction area with the dummy sync block, it is possible to prevent an area where no data is recorded from being generated in the special reproduction area.

A tenth invention is according to the first to ninth inventions, wherein the input bit stream is an MPE.
If the bit stream conforms to the G standard, a header analysis means for analyzing a PES header included in the input bit stream, and a DSM trick mode flag in the PES header indicating that the bit stream is data for special reproduction, A DSM trick mode flag setting means for setting to a predetermined value, and storing special reproduction data extracted from the bit stream and securing a 1-byte area for a trick mode field at a predetermined address in advance. A trick mode field is inserted at a predetermined position in the data for reproduction, and the PE of the bit stream is inserted.
A memory means for previously securing a trick mode field at a predetermined position in the S header; and a trick mode field value inserting means for inserting predetermined data indicating a special reproduction condition into the trick mode field when reading data from the memory means. Prepare.

As described above, according to the tenth aspect, in the first to ninth aspects, the trick mode field is secured in advance in the memory for storing the image data for special reproduction, so that the trick mode is included in the stream. A mode field can be easily inserted. Further, by setting a trick mode field value according to the trick play condition later in the trick mode field of the trick play image data stored in one memory, both the trick play field for fast forward playback and the trick play field for rewind playback are set. It is possible to generate recording data for special reproduction. Further, by generating the special reproduction recording data by correctly rewriting the DSM trick mode flag, it is possible to generate a special reproduction stream conforming to the MPEG standard.

An eleventh invention is an invention according to the first to tenth inventions, wherein a bit stream composed of a video signal and an audio signal encoded by utilizing the correlation between screens is: It is characterized by being coded data according to the MPEG system. As described above, the eleventh invention includes the first to the first
1 shows a typical bit stream used for the invention of FIG.

A twelfth invention is a reproducing apparatus for digitally reproducing recording data from a recording medium on which recording data for normal reproduction and recording data for special reproduction are recorded,
A reproduction means for reproducing, via a reproduction head, recording data for normal reproduction and recording data for special reproduction recorded on a recording medium, and a special reproduction stream is generated from the recording data for special reproduction reproduced by the reproducing means. A special reproduction stream generating means for regenerating recording data for normal reproduction reproduced by the reproducing means to generate a normal reproduction stream, and a normal reproduction stream and a special reproduction stream according to the reproduction mode. Switch means for switching which is to be output as the reproduction stream, and the special reproduction stream generation means performs the Nth reproduction at the time of the special reproduction.
After outputting the (N is a positive integer) trick play stream, if the subsequent (N + 1) th trick play stream cannot be output within a predetermined time interval, the playback image included in the Nth trick play stream The time information for performing the output time management is rewritten to a value after the time information of the Nth trick play stream and to a value before the time information of the succeeding (N + 2) th trick play stream. Is output again.

As described above, according to the twelfth aspect, at the time of the special reproduction, the special reproduction includes the time information and the control information which are reproduced at a predetermined interval and recorded on the recording medium for the special reproduction. It is only necessary to reproduce and output the recorded data.
Therefore, a circuit for newly generating time information and control information at the time of special reproduction is not required, and the circuit scale can be significantly reduced. Further, by outputting the trick play stream in which the time information is rewritten, it is possible to obtain a good trick play image without disturbance.

A thirteenth invention is an invention according to the twelfth invention, wherein the reproduction stream is coded data according to the MPEG system. As described above,
The thirteenth invention shows a typical stream reproduced in the twelfth invention.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION In each of the embodiments of the present invention, a bit stream composed of a video signal and an audio signal encoded by utilizing the correlation between screens will be described below.
The case where the EG transport stream is targeted will be described as an example.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
FIG. 3 is a block diagram illustrating a configuration of a recording apparatus according to an embodiment. In FIG. 1, the recording apparatus according to the first embodiment includes:
It includes a recording data generation unit for normal reproduction 1, a recording data generation unit for special reproduction 2, a packet generation unit 3, a control unit 4, a recording unit 5, and a recording head 6.

The recording data generator 1 for normal reproduction and the recording data generator 2 for special reproduction have a transport packet format composed of a video signal and an audio signal encoded by utilizing the correlation between screens. The bit stream 201 is input. The recording data generating unit 1 for normal reproduction generates recording data for normal reproduction composed of a plurality of predetermined recording blocks from the input bit stream 201. The recording data generation unit 2 for trick play performs trick playback (fast forward playback, rewind playback, etc.) composed of a plurality of recording blocks predetermined from the input bit stream 201.
Generate recording data for The packet generation unit 3 generates a time information packet indicating time information for managing output time of a reproduced image and a control information packet indicating control information for decoding the recording data for special reproduction,
The recording data is output to the special reproduction recording data generation unit 2. Control unit 4
Provides a reference signal necessary for the packet generator 3 to generate the time information packet and the control information packet.
The recording unit 5 determines the recording order of both data in order to record the recording data for normal reproduction and the recording data for special reproduction in a predetermined area on the recording medium 202. The recording head 6 is a head device for recording data on the recording medium 202, and is, for example, a magnetic head. Recording medium 2
Numeral 02 is a tape-shaped recording medium, for example, a magnetic tape.

Hereinafter, the operation of the recording apparatus according to the first embodiment having the above configuration will be described in detail with reference to FIGS. FIG. 2 is a block diagram showing a more detailed configuration of the recording data generating unit 2 for trick play, the packet generating unit 3 and the recording unit 5 in FIG. FIG. 3 is a diagram showing the relationship between transport packets and sync blocks. FIG. 4 is a diagram illustrating extraction of an I-picture and reduction of the data amount. In FIG. 4, FIG. 4A is an example of the configuration of the bit stream 201, and one GOP is composed of 12 pictures of I, P, and B. FIG. 5 is a diagram illustrating an example of PTS generation. FIG. 6 is a schematic diagram of a recording track on the recording medium 202 for recording recording data for fast-forward reproduction. FIG.
FIG. 3 is a diagram illustrating an example of a predetermined position on a recording medium 202 for recording time information and control information. FIG. 8 is a diagram for explaining a difference between a control information packet in the case of recording data for normal reproduction and a control information packet in the case of recording data for special reproduction.

In FIG. 2, the recording data generating unit 2 for special reproduction includes an I picture extracting unit 21 and a high-frequency component deleting unit 22.
, A memory 23, a PES header rewriting unit 24, and a special reproduction sync block generation unit 25. Also,
The packet generation unit 3 includes a counter unit 31, a PCR value generation unit 32, a PTS generation unit 33, a PCR packet generation unit 34, a PSI packet generation unit 35, a Null packet generation unit 36, and a selector unit 37. Prepare. The recording section 5 includes a recording formatting section 51, a recording modulation section 52, and a recording amplifier 53.

The bit stream 201 in the transport packet format is input to the recording data generating unit 1 for normal reproduction and the I picture extracting unit 21. First, the recording data generation unit 1 for normal reproduction receives the input bit stream 2
From 01, a data string for normal reproduction composed of a plurality of recording blocks is generated. This recording block is called a sync block, and has a length of 112 bytes as shown in FIG. 3, and one transport packet is composed of two sync blocks. The data string of the sync block for normal reproduction generated in this manner (hereinafter, referred to as recording data for normal reproduction) is sequentially output to the recording formatting section 51.

The I-picture extracting unit 21 extracts only the stream constituting the I-picture which is an image for special reproduction from the input bit stream 201 (FIG. 4 (a)) (FIG. 4 (b)). The data is output to the high-frequency component deletion unit 22 as data. Here, the I picture extraction unit 21
By examining PAT packets and PMT packets, which are stream control information included in the bit stream 201, a target video data stream is extracted. Further, by examining a header portion indicating information about the stream of the bit stream 201, Only the stream constituting the I picture which is the data encoded in the frame is extracted.

The high-frequency component deletion unit 22 deletes the AC coefficient indicating the high-frequency component of the encoded data from the I-picture data output from the I-picture extraction unit 21 to reduce the data amount ( FIG. 4 (c)). For example, if the I picture data is image data compressed by discrete cosine transform (DCT), the data amount can be easily compressed by reducing the number of effective AC coefficients. Note that the amount of data to be deleted is not uniquely determined, but can be freely set based on a desired image quality, a limitation on a recording area on the recording medium 202, and the like. By reducing the data amount in this way, the high-frequency component of the special reproduction image at the time of special reproduction is lost and becomes a blurred image. Is an easy-to-view image. Then, the high-frequency component deletion unit 22
The I-picture data after the high-frequency reduction processing (hereinafter referred to as special reproduction image data) is stored in the memory 23, and the data amount of the special reproduction image data is stored in the PTS generation unit 33.
Output to

On the other hand, the control section 4 sends a scan switching signal indicating the scanning state of the recording head 6 to the counter section 31.
A selector for the PCR value generator 32 and a frame rate control signal for indicating a frame update cycle of a video device (not shown) for reproducing and displaying the recorded data to the PTS generator 33. An output packet switching signal for recording a packet at a predetermined position is output to the unit 37.

The counter unit 31 controls the recording head 6 according to the scan switching signal input from the
02 is counted, and a scan signal is output to the PCR value generator 32 every time the number of scans becomes n.
The PCR value generation unit 32 performs a simple calculation of switching an offset value corresponding to the cylinder rotation speed based on the scan signal input from the counter unit 31 and the cylinder rotation speed input from the control unit 4 to obtain a reference time of the encoded data. Is generated and output to the PTS generator 33 and the PCR packet generator 34. The PTS generation unit 33 receives the data amount of the special reproduction image data from the high-frequency component deletion unit 22, the frame rate control signal from the control unit 4, and the PCR value from the PCR value generation unit 32, and decodes the reproduction time. A PTS field value, which is time information indicating the timing at which the output image data is output, is generated by normalizing according to the frame rate control signal, and is output to the PES header rewriting unit 24. Hereinafter, a method of normalizing according to the frame rate control signal will be described with reference to FIG.

As shown in FIG. 5, each I picture data 304 has a PTS field 305 indicating a PTS in a header portion. In FIG. 5, the time interval T
f indicates a frame update cycle of the video output device, and the horizontal axis indicates a reference time. Since the PTS is a value for outputting a decoded image, it must be a value at least after the time when the last data constituting the image is input. Therefore, first, when outputting the image for special reproduction, the PTS generation unit 33 sets the reference time output from the PCR value generation unit 32 so that the predetermined time relationship between the decoder and the video output device matches, 4 is related to the frame update period Tf indicated by the frame rate control signal output from the control unit 4. Then, the PTS generating unit 33 sets the value of the PTS to a time after the time when the last data constituting the I picture data is output at the time of trick play, and
It is generated by normalizing so as to synchronize with the frame update period Tf. Therefore, the value of PTS is the frame update period Tf
It is a discrete value that can be taken every time. For example, as for the I picture data I1 in FIG. 5, since the time at which the last data of the I picture data I1 is output is te, the relationship of PTS> te is satisfied as a PTS value candidate, and the frame update period Is the PTS value of the I picture data I1 which is the closest value t2 to te that is synchronized with.
The value of each PTS generated in this way is rewritten by the PES header rewriting unit 24 as the value of the PTS field in the PES header part of the I picture data.

As described above, by normalizing the value of the PTS with the frame update period Tf of the video output device, the decoded image is always output from the head of the image in the output of the decoded image. A good image which is not updated to the next image can be obtained.

Referring to FIG. 2 again, PCR packet generator 34 generates a PCR packet based on the PCR value input from PCR value generator 32 and outputs the packet to selector 37 at predetermined time intervals. The PSI packet generator 35 has a fixed value control information packet (PAT packet and PMT packet) for trick play in advance, and outputs this control information packet to the selector 37 at predetermined time intervals.
The null packet generator 36 generates a null packet, which is invalid data having no meaning in the MPEG standard, and outputs the null packet to the selector 37. The selector unit 37
According to the output packet switching signal input from the control unit 4,
Either the PCR packet output from the PCR packet generating unit 34, the PAT packet output from the PSI packet generating unit 35, or the Null packet output from the Null packet generating unit 36 is sent to the sync block generating unit 25 for trick play. Output. Note that when a null packet is not required (for example, when stuffing described later is not performed), the null packet generation unit 3
6 can be omitted.

Here, the relationship between a predetermined recording position for recording time information and control information and a PCR value as a reference time is as follows.
Referring to FIG. 6, a case of fast forward special reproduction will be described as an example. In the normal reproduction area 301, recording data for normal reproduction is recorded. In the special reproduction area 302 indicated by TP1 to TP19, recording data for special reproduction is recorded. T in the special reproduction area 302
At a predetermined position 303 of P1, TP9, TP17 (shown by oblique lines in FIG. 6), time information and control information for special reproduction are stored.
Recording is performed at predetermined intervals t1 and t2. FIG. 6 shows a case where t1 and t2 have the same interval. The values of the predetermined intervals t1 and t2 are 100 m, which is the maximum allowable output interval between the time information packet and the control information packet defined by the MPEG standard during trick play.
This value satisfies s. For example, in the case of fast forward playback at 12 × speed, the head to be played scans along a locus 311 (indicated by a dashed line in FIG. 6) and moves from TP1 to T
The special reproduction recording data recorded in the special reproduction areas 302 and 303 up to P19 are sequentially reproduced. At this time, by reproducing the data in the special reproduction area 303 in which the time information and the control information for the special reproduction are recorded, the time information packet and the control information packet are not inserted at the time of the special reproduction.
The time information packet and the control information packet can be output according to the MPEG standard.

Next, the relationship between a predetermined recording position and a PCR value as time information to be recorded will be described. By recording time information in advance regularly at predetermined intervals as described above, the position where the time information is recorded is determined. In FIG. 6, the time when TP9 is reproduced is the time when TP1 is reproduced.
Since it is the time after one, the PCR value recorded in TP9 (referred to as PCR9) is a value obtained by adding the offset value for t1 to the PCR value recorded in TP1 (referred to as PCR1), that is, (PCR9 ) = (PCR1) +
(Offset value for t1). Similarly, if the PCR value recorded in TP17 is PCR17, (PCR17) = (PCR9) + (offset value for t2). This makes it possible to generate a PCR value by a simple calculation for each predetermined position where time information is to be recorded. The predetermined interval at which the time information is recorded may, of course, be other than the combination of t1 or t1, t2 described above, or other cases where the number of combinations increases, such as intervals t1, t2, and t3.

Next, an example of a predetermined position for recording time information and control information on the recording medium 202 will be described with reference to FIG. FIG. 7A shows that t1 and t2 are the same (t1
= T2), which synchronizes with the scanning of the head at the time of trick play, and the same trick play sync block number (recording medium 2) is recorded every time the trick play time information and control information are recorded.
02, the area is recorded in the area of (the number of the area for recording one sync block). FIG. 7B shows t1 and t2.
Are the same (t1 = t2) and are not synchronized with the scanning of the head during the special reproduction, and the time information and the control information are recorded in the area of the special reproduction sync block number which is different for each recording. FIG. 7C shows that t1 is larger than t2 (t1>
t2), where time information for special reproduction and control information are periodically recorded at (t1 + t2). FIG. 7 (d)
In the case where t1 is smaller than t2 (t1 <t2), recording is performed so that the special reproduction area in which the time information and the control information are recorded by one scanning of the head in the special reproduction is reproduced twice.

A specific example of the recording position of the time information will be described.
In the D-VHS standard, the special playback sync block number for recording data is a value of 0 to 101, and in the case of fast-forward playback data, the special playback sync block numbers 98 and 99 are used. This is a block recording position, and in the case of rewind reproduction data, it is a special reproduction sync block recording position where the special reproduction sync block numbers are 2 and 3. Here, the time information for special reproduction and the control information to be recorded are in a transport packet format, and one transport packet is composed of two sync blocks. Therefore, recording requires two sync blocks. . Note that the sync block number for special reproduction is not limited to the values of 0 to 101 described above, and other values may be used.

It is sufficient that the time information and the control information exist in the special reproduction area for special reproduction, and the special reproduction area for recording the time information and the control information is used for the special reproduction as described above. May be other than the first or last area of the special reproduction area synchronized with the scanning of the head. Further, the time information and the control information may be recorded in different special reproduction areas. Further, the interval for recording the time information and the interval for recording the control information may be the same or different from each other. Further, the time information packet and the control information packet may be recorded in a continuous area, or a plurality of time information or a plurality of control information may be repeatedly recorded in the same special reproduction area.

Referring again to FIG. 2, PES header rewriting section 24 converts the PES of the special reproduction image data (I picture data) stream input from high frequency component deletion section 22.
The PTS field value included in the header portion is rewritten to the PTS field value output by the PTS generation unit 33, and if necessary, the PTS field value is deleted.
The ES header is rewritten and output to the special reproduction sync block generation unit 25. The special reproduction sync block generation unit 25 includes a special reproduction image data (I picture data) stream for special reproduction output from the PES header rewriting unit 24, a time information packet and a control information packet selectively output by the selector unit 37. Are multiplexed, and in the same manner as in the processing described in the above-described normal reproduction recording data generation unit 1, a data string of a special reproduction sync block which is recording data for special reproduction (hereinafter, special reproduction Recording data). The generated recording data for trick play is sequentially output to the recording unit formatting unit 51.

Referring to FIG. 8, the difference between a control information packet for normal reproduction recording data and a control information packet for special reproduction recording data will be described. 8A shows a control information packet in the case of recording data for normal reproduction, and FIG. 8B shows a control information packet in the case of recording data for special reproduction. The recording data for normal reproduction is generated by directly converting a PAT packet, a PMT packet, and video data packets and audio data packets other than the control information, which are control information of the input bit stream 201, into sync blocks. FIG.
In the example of (a), the PID 30 of the PAT packet 306a
7a is “0”, and the PAT packet 306a has the PM
“N0” which is the PID 307b of the T packet 306b is shown. The PMT packet 306b includes “n” which is the PID 307c of the image data packet 306c.
1 "and the PID 307d of the voice data packet 306d.
“N2” is shown.

On the other hand, in the generation of the recording data for special reproduction, the bit stream 20 inputted as described above is used.
1, only I picture data is extracted for special reproduction,
Other data such as voices are not extracted. Therefore, if the control information (PAT packet, PMT packet) of the input bit stream 201 remains as it is, it will include information of data other than I picture data which is not extracted as recording data for special reproduction. Therefore, the PAT packet 3 which is the control information for special reproduction in which the control information regarding the extracted image data (I picture data) is held and the control information regarding the unextracted data is deleted.
08a, PMT packet 308b is newly generated, and PM
Image data packet 308c indicated by T packet 308b
Are converted into sync blocks to generate recording data for special reproduction. Therefore, in the example of FIG. 8B, the control information (PAT packet 308a, PMT
The PID of the packet 308b) is the control information (PAT packet 306a, PMT packet 306) for normal reproduction.
b) has the same value as the PID, but the PMT packet 308
The PID of the image data indicated by b is only “N1” which is the PID 309c of the extracted image data 308c.

As described above, by regenerating the control information for trick play and deleting unnecessary information, the possibility of the decoder malfunctioning when an error occurs in the stream is eliminated, and a more stable trick play image is obtained. Can be reproduced. Although FIG. 8 illustrates the case where the number of programs indicated by the PAT packets 306a and 308a is one, the same applies to two or more programs. Also, the P shown in the PMT packet 308b
The ID is not limited to the above-described image data, but may be other data.

Referring to FIG. 2 again, the recording formatting unit 51 includes a normal reproduction recording data (sync block) output from the normal reproduction recording data (sync block) generation unit 1 and a special reproduction sync block generation unit. The recording data for sync reproduction in the sync block format output from the section 25 is input, and the recording data for normal reproduction is recorded in the normal reproduction area, and the recording data for special reproduction is recorded in the special reproduction area. A recording data sequence is generated according to the recording format. The recording modulation section 52 converts the recording data string output from the recording formatting section 51 into a signal having a shape suitable for a magnetic recording / reproducing system, and outputs the signal to the recording amplifier 53. Then, the recording amplifier 53
After a predetermined amplification process is performed on the print data sequence input from, the output is output to the print head 6. Recording head 6
Records the recording data sequence output from the recording amplifier 53 on the magnetic tape 202 sequentially. At this time, the special reproduction time information and the control information output at predetermined time intervals by the packet generation unit 3 are, as described above, the magnetic tape 202.
They are regularly arranged at predetermined positions in the special reproduction area configured above.

As described above, according to the recording apparatus according to the first embodiment of the present invention, the time information and the control information generated by the packet generation unit 3 are synchronized with the scanning of the recording head 6 to record the recording medium. Recording is regularly performed in advance at a predetermined position in the special reproduction area formed on the area 202. Therefore, it is not necessary to individually monitor the packet transmission intervals required for each special reproduction, and the generation of time information, which was conventionally complicated, is a simple operation of adding a fixed value according to the recording position of the special reproduction area. And time information can be generated by a small-scale circuit. Also,
It is not necessary to generate time information and control information at the time of special reproduction, and the circuit scale of the reproduction apparatus can be reduced, which is convenient for configuring a reproduction-only apparatus.

In the first embodiment, I-picture data is used as data for generating special reproduction recording data. However, P-picture data or B-picture data may be used. Further, in the first embodiment, the case where the MPEG transport stream is targeted has been described as an example. Therefore, PCR and PTS are used as time information, and PAT and PTS are used as control information.
PMT was used. However, when a bit stream composed of a video signal and an audio signal coded using correlation between screens other than the MPEG transport stream is used, time information and control information corresponding to the bit stream are used. May be used.

(Second Embodiment) The second embodiment of the present invention is different from the first embodiment in that the reproduced stream output during special reproduction is recorded at the time of recording so as not to cause a problem during decoding. In consideration of the necessity of outputting the data while maintaining the input predetermined time interval, a time (time stamp) for controlling the output of the reproduction stream is added to the special reproduction sync block.

FIG. 9 is a block diagram showing the configuration of a recording apparatus according to the second embodiment of the present invention. In FIG.
The recording apparatus according to the second embodiment includes a recording data generation unit 1 for normal reproduction, a recording data generation unit 2 for special reproduction, a packet generation unit 3, a control unit 4, a recording unit 5, a recording head 6,
And In addition, the recording data generation unit 2 for special reproduction,
I picture extraction unit 21, high frequency component deletion unit 22, memory 23, PES header rewriting unit 24, special playback sync block generation unit 25, and time stamp generation unit 2.
6 is provided. The packet generator 3 includes a counter 31, a PCR value generator 32, a PTS generator 33,
PCR packet generator 34 and PSI packet generator 3
5 and a selector unit 37. Also, the recording unit 5
A recording formatting unit 51, a recording modulation unit 52,
And a recording amplifier 53.

As shown in FIG. 9, the recording apparatus according to the second embodiment includes a time stamp generation section 2 in the recording data generation section 2 for trick play of the recording apparatus according to the first embodiment.
6 is added. The other configuration of the recording apparatus according to the second embodiment is the same as the configuration of the recording apparatus according to the first embodiment, and the other configurations are denoted by the same reference numerals and described. Is omitted.

First, the sync block generator for special reproduction 2
Reference numeral 5 denotes a special reproduction sync block number (for example, 0 to 101) indicated in the header of the special reproduction sync block which is the special reproduction recording data to be generated, for the time stamp generation unit 26. , Which does not limit the sync block number for trick play) and requests a time stamp value to be added to the sync block for trick play. The time stamp generation unit 26 generates a fixed time stamp value corresponding to each special reproduction sync block number input from the special reproduction sync block generation unit 25 on a one-to-one basis, and returns the time stamp value to the special reproduction sync block generation unit 25. Sync block generator for special playback 2
5 receives the time stamp value returned from the time stamp generation unit 26 and inserts the time stamp value into the time stamp area (see FIG. 3) included in the header information part of each sync block. After that, the special reproduction sync block generation unit 25 outputs the special reproduction sync block into which the time stamp value has been inserted to the recording formatting unit 51 as special reproduction recording data.

FIG. 10 is a diagram showing an example of the relationship between the generated time stamp value and the trick play sync block number. As shown in FIG. 10, the trick play sync block number and the time stamp value correspond one to one. When the trick play sync block number is n0, the time stamp value is t0, and the trick play sync block number is n1. In the case of, the time stamp value is t1. By preparing a conversion table having a characteristic as shown in FIG. 10 or a simple arithmetic circuit in the time stamp generation unit 26, it is possible to easily obtain a time stamp value.

As described above, the recording apparatus according to the second embodiment of the present invention is provided with the time stamp generating section 26 for generating the time stamp value by a conversion table or a simple operation, and Is generated from the special playback sync block number. As a result, it is possible to reduce the circuit scale for adding a time stamp, as compared with the related art.

(Third Embodiment) The third embodiment of the present invention is different from the first embodiment in that the trick play recording data generation unit 2 stores the trick play data stored in one memory. Special playback recording data for both fast forward playback and rewind playback is generated from image data. The configuration of the recording apparatus according to the third embodiment is the same as the configuration of the recording apparatus according to the first embodiment, and the other configurations are denoted by the same reference numerals and description thereof is omitted. I do.

The high-frequency component deletion unit 22 deletes the AC coefficient indicating the high-frequency component of the encoded data from the I-picture data output from the I-picture extraction unit 21 to reduce the data amount. Image data for special reproduction (I picture data after high frequency reduction processing) is sequentially stored in the memory 23.
Here, the high-frequency component deletion unit 22 creates a memory map in the memory 23 and sequentially stores the special reproduction image data.

FIG. 11 is a diagram showing an example in which image data for special reproduction is stored in a memory map in the memory 23. In FIG. 11, first blocks 1 to 1 of the memory map
The fourteenth block corresponds to the amount of special reproduction image data recorded in one special reproduction area, the first block is the head data of the special reproduction image data, and the fourteenth block is the special data. This is the final data of the image data for reproduction. The data of the 14th block indicates that the data amount is smaller than the block size. As described above, the high-frequency component deletion unit 22 sequentially stores the special reproduction image data in the memory map of the memory 23.

Next, how to use each special reproduction image data stored in the memory map of the memory 23 as described above will be described. First, when generating the fast-forward playback data, the high-frequency component deletion unit 22 moves the special playback image data stored in the memory map of the memory 23 from the first block at the beginning to the last fourteenth block. They are read out in order and output to the PES header rewriting unit 24. On the other hand, when generating the rewind reproduction data, the high-frequency component deletion unit 22 moves the special reproduction image data stored in the memory map of the memory 23 from the last fourteenth block to the first first block. Read in order,
Output to the PES header rewriting unit 24. However, in this case, since the data amount of the fourteenth block is less than the data amount to be read, the high-frequency component deletion unit 22 reads out the insufficient data from the back of the thirteenth block by 1
Read the data amount of the block. After that, the high-frequency component deletion unit 22 reads out data by performing the same operation for each block. Therefore, when reading the data of the first block, the high-frequency component deletion unit 22 reads out less than one block of data. It should be noted that the data portion of less than one block is processed by the Null packet generation unit 36 via the selector unit 37 when the special reproduction sync data generation unit 25 generates the special reproduction recording data. By inserting
Processing is performed so as to form data for one block.

Here, the high-frequency component deletion unit 22 determines whether the data for fast-forward playback and the data for rewind playback are on the recording medium 2.
02, the special playback areas to be recorded are different,
Either generation of fast-forward reproduction data or rewind reproduction data ends reading of special reproduction image data first. In this case, the person who has finished reading the special reproduction image data first waits until the processing of the one which has not finished reading the special reproduction image data has been completed, and stores the next special reproduction image data in the memory 23. It does not start writing. That is, the high-frequency component deletion unit 22 performs the fast forward reproduction data generation and the rewind reproduction data generation,
After finishing reading the image data for special playback,
The next special reproduction image data is written to the memory 23. When the preparation of the next special reproduction image data (storage in the memory map) is completed, the high-frequency component deletion unit 22 starts reading the next special reproduction image data.

Next, the special reproduction area formed on the recording medium 202 will be described. The special playback area includes a fast-forward playback area and a rewind playback area corresponding to a playback speed different from the normal playback, and the special playback recording data recorded in each area is correct during the special playback. They are arranged to be played in order. The recording data for special reproduction for fast-forward reproduction is recorded in order from the front of the recording data for special reproduction since the direction of the special reproduction is the forward direction when recording. However, the special reproduction recording data for rewind reproduction is recorded in order from the rear of the special reproduction recording data so that the special reproduction is performed correctly during rewind reproduction because the direction of the special reproduction is opposite to the recording direction. You.

FIG. 12 shows an example of the 12
FIG. 3 is a diagram illustrating an example of a recording position of double-speed special reproduction recording data. In FIG. 12, the special reproduction area 409 is
An area for recording recording data for special reproduction for fast-forward reproduction, and an area 410 for special reproduction is an area for recording recording data for special reproduction for rewind reproduction.
A trajectory 411 indicates the trajectory of the head during fast-forward playback, and a trajectory 412 indicates a trajectory of the head during rewind playback. Further, N is the number of tracks, and the case where N = 24 is described. Further, the numbers 1 to 14 in the special reproduction areas 409 and 410 correspond to the first block to the fourteenth block of the data constituting the special reproduction image data on the memory map in FIG.
It corresponds to the block number, with number 1 being the first data and number 14 being the last data. Note that NL indicates a Null packet.

When the recording data for special reproduction is processed in units of 24 tracks (N = 24), immediately before the recording processing in units of 24 tracks is completed, the final stream of one image data for special reproduction is output and immediately thereafter. Instead of starting to output the next stream of special reproduction image data, the packet generation unit 3 outputs Null packets until the recording process in units of 24 tracks is completed, and stuffs the special packets in the special reproduction area. For example, in the recording of the special playback data for fast-forward playback, if the output of one piece of special playback image data (14 + NL) is completed during the recording process of the 24-track unit, the recording process of the 24-track unit is performed from there. NL is recorded in the special reproduction area until the processing is completed. When the recording process in units of 24 tracks is completed, the recording process for recording the next special reproduction image data starts. In FIG. 12, fast-forward reproduction data (1
Although the NL is recorded next to the special reproduction area composed of 4 + NL) or rewind reproduction data (1 + NL), the next special reproduction image data may be used. Also,
Even when stuffing is performed in the NL, special reproduction recording data of time information and control information may be recorded in the special reproduction area. Further, all of one special reproduction area may be stuffed with NL.

As described above, according to the recording apparatus of the third embodiment of the present invention, the special reproduction image data is stored in one memory 23 in a predetermined order, and the time when the fast-forward reproduction data is generated is set to By making the reading direction (order) of the data different from that at the time of generation of the reverse reproduction data, special reproduction recording data for fast forward reproduction and rewind reproduction are generated respectively. As a result, it is not necessary to have a memory for generating data for fast-forward reproduction and data for rewind reproduction, respectively, and the memory capacity can be reduced by half. Further, by stuffing the special reproduction area with a null packet (NL), it is possible to prevent an area where no data is recorded in the special reproduction area from occurring.

In the third embodiment, the description has been made such that the null packet to be inserted is provided from the packet generation unit 3. However, a predetermined number of null packets is stored in the memory 23 and provided. Is also good. In the third embodiment, the case where a null packet is used as an invalid data packet to be stuffed is described. However, a dummy sync block which is an invalid sync block in the D-VHS standard can be used. is there.

(Fourth Embodiment) The fourth embodiment of the present invention is different from the first embodiment in that processing relating to the DSM trick mode is performed. This D
The SM trick mode flag indicates that the stream of the MPEG standard is a stream for special reproduction, and is arranged at a predetermined position in the PES header portion. Therefore, the input ordinary bit stream 201 is DS
Since there is no M trick mode field, a DSM trick mode flag must be set when recording data for special reproduction is generated, and a DSM trick mode field must be added.

FIG. 13 is a block diagram showing the configuration of a recording apparatus according to the fourth embodiment of the present invention. In FIG. 13, the recording apparatus according to the fourth embodiment includes a recording data generation unit 1 for normal reproduction, a recording data generation unit 2 for special reproduction,
It includes a packet generation unit 3, a control unit 4, a recording unit 5, and a recording head 6. The trick play recording data generation unit 2
It includes a picture extraction unit 21, a high-frequency component deletion unit 22, a memory 23, a PES header rewriting unit 24, a special reproduction sync block generation unit 25, and a DSM generation unit 27.

As shown in FIG. 13, the recording apparatus according to the fourth embodiment has a configuration in which a DSM generation unit 27 is added to the recording data generation unit 2 for trick play of the recording apparatus according to the first embodiment. It is. The other configuration of the recording apparatus according to the fourth embodiment is the same as the configuration of the recording apparatus according to the first embodiment, and the other configurations are denoted by the same reference numerals and described. Is omitted.

Hereinafter, the operation of the DSM generator 27 will be described with reference to FIGS. 14 and 15. FIG. 14 shows a detailed configuration of the DSM generation unit 27 of FIG.
FIG. 14, the DSM generation unit 27 includes a PES header analysis unit 71, a DSM trick mode flag setting unit 72, and a trick mode field value insertion unit 73. FIG. 15 is a diagram illustrating an example of the structure of the memory 23.

The memory 23 inputs and stores the I picture data 207, which is image data for special reproduction, from the high-frequency component deletion unit 22. At this time, when setting the DSM trick mode flag 314 to a value indicating the DSM trick mode, the memory 23 secures a region of the DSM trick field 315 having a length of 1 byte at a predetermined address in advance, or If the DSM trick mode is already set when the mode flag is input, the DSM trick mode field included in the input I picture data 207 is stored in a one-byte storage area secured at a predetermined address. Here, the DSM trick mode field 315 is reserved in the memory 23 in advance when generating special playback data for fast-forward playback and rewind playback from I-picture data stored in one memory. Trick mode field 31
This is because it is necessary to insert a value corresponding to special playback conditions such as fast-forward playback or rewind playback into data 5 when reading data.

The stream of the MPEG standard is input in the transport packet format. If one byte of data is to be inserted into an arbitrary portion of the data in the transport packet format, the data after the data to be inserted is added. Must be shifted, that is, all transport packets after the data to be inserted must be reconstructed, which is a very difficult process. Here, in the generation of the recording data for special reproduction, the image data for special reproduction (I picture data) is not in the transport packet format in order to remove the high frequency component, but is elementary with no restriction on the data length.・ Memory 2 in stream format
3 is stored. In the elementary stream, since there is no restriction on the data length of the transport packet in units of 188 bytes, new data can be freely inserted at an arbitrary position. Therefore, by performing the insertion processing of the DSM trick mode field 315 together with the high-frequency component deletion processing performed after extracting the I-picture data for special reproduction, the processing can be easily performed.

On the other hand, the PES header analysis unit 71 inputs the I picture data 207 input in the transport packet format from the high frequency component deletion unit 22, analyzes the PES header portion of the I picture data 207, and The position of the mode flag, the value of the position, and the presence or absence of the DSM trick mode field are detected, and are output to the DSM trick mode flag setting unit 72 as an analysis result.
The DSM trick mode flag setting section 72 needs to rewrite the DSM trick mode flag 314 indicated in the PES header section of the I picture data 207 stored in the memory 23 according to the analysis result output from the PES header analysis section 71. In some cases, a signal for rewriting the DSM trick mode flag 314 to a value indicating the DSM trick mode is output to the memory 23. Also, DS
M trick mode flag setting section 72 sets a DSM trick mode flag 314 and outputs a control signal instructing insertion of a trick mode field value to trick mode field value inserting section 73.

Trick mode field value insertion section 73
Generates a trick mode field value according to the special reproduction condition of the special reproduction image data based on the control signal output from the DSM trick mode flag setting section 72, and stores the generated trick mode field value in the memory 23. Corresponding DSM trick mode field 315
Write to. Here, in the case of trick play data in the fast forward direction, the trick mode field value insertion unit 73
A fixed value dedicated to fast-forward playback is generated as a trick mode field value, and in the case of special playback data in the rewind direction, a fixed value dedicated to rewind playback is generated as a trick mode field value. A fixed value indicating the condition is written in the DSM trick mode field 315 of the memory 23. Then, the memory 23 stores the DSM
The special reproduction image data 209 in which the trick mode flag 314 and the DSM trick mode field 315 are set is output to the high frequency component deletion unit 22.

The DSM generating section 27 does not include the PES header analyzing section 71, and the DSM trick mode field 315 is always inserted into all of the input special trick picture data (I picture data) 207. You may do so. Further, the trick mode field value may be inserted after being read from the memory 23 as well as being written into the DSM trick mode field 315 of the memory 23.

As described above, according to the recording apparatus of the fourth embodiment of the present invention, by securing the DSM trick mode field 315 in the memory 23 for storing the special reproduction image data in advance, the stream ( The DSM trick mode field can be easily inserted into (I picture data). Further, by setting a trick mode field value according to the special reproduction condition later in the DSM trick mode field 315 of the special reproduction image data stored in one memory 23, the fast forward reproduction and the rewind reproduction can be performed. Of the special reproduction recording data can be generated. Further, by properly rewriting the DSM trick mode flag 314 to generate recording data for special reproduction, it is possible to generate a stream for special reproduction conforming to the MPEG standard.

The functions described in the second to fourth embodiments can be used for the recording apparatus according to the first embodiment in an arbitrary plural combination.

(Fifth Embodiment) FIG. 16 is a block diagram showing a configuration of a reproducing apparatus according to a fifth embodiment of the present invention. 16, the playback device according to the fifth embodiment includes a playback head 8, a playback unit 9, a special playback stream generation unit 10, a normal playback stream generation unit 11, and a playback stream switch unit 12. . The reproducing unit 9 includes a reproducing head amplifier 91 and a reproducing demodulating unit 92. The trick play stream generation unit 10 includes a trick play sync block extraction unit 101, a reliability determination unit 102,
It includes a memory 103 and a trick play packetizer 104. The normal reproduction stream generation unit 11 includes a normal reproduction sync block extraction unit 111 and a normal reproduction packetization unit 11.
2 is provided.

Hereinafter, the operation of the reproducing apparatus according to the fifth embodiment having the above configuration will be described. The recording medium 202 is a tape-shaped recording medium, for example, a magnetic tape. The reproducing head 8 is a head device for reproducing data recorded on the recording medium 202, and is, for example, a magnetic head. The head amplifier 91 performs a predetermined amplification process on the data sequence reproduced by the reproduction head 8, and outputs the data sequence to the reproduction demodulation unit 92. The reproduction demodulation unit 92 demodulates the recording signal modulated by the recording device into the original recording signal (at the time of demodulation, error correction is performed using the error correction parity added to each sync block). The reproduced and demodulated data sequence is output to the special reproduction sync block extraction unit 10.
1 and output to the normal reproduction sync block extraction unit 111.

The trick play sync block extraction unit 101
At the time of special reproduction, a data string reproduced by the reproduction demodulation unit 92 is input, and information indicating that it is recording data for special reproduction from the header part of the sync block, that is, reproduced from the special reproduction area in the recording track. A special reproduction sync block is extracted by detecting and removing synchronization data, ID data, and parity for error correction from the data string.
The extracted trick play sync block constitutes an I picture. The trick play sync block is output to the reliability determination unit 102.

The reliability judging unit 102 receives the special reproduction sync block output from the special reproduction sync block extraction unit 101, judges the reliability of the sync block from information indicating the error correction result, and outputs the special reproduction sync block. The block is stored in the memory 103 at an address corresponding to the special reproduction sync block number. Here, the reliability determination unit 102
When a trick play sync block having the same trick play sync block number is played, a sync block with high reliability is preferentially selected from the memory 103 based on the reliability information.
To memorize. For example, a low-reliability sync block is first stored in the memory 103, but when the same high-reliability sync block is obtained next, the data of the sync block obtained later is stored first. The data of the sync block is overwritten.

When data necessary for forming an I picture is stored in the memory 103, the trick play packetizing unit 1
04 reads the data stored in the memory 103,
The transport packet format data is reconstructed from the sync block format data, and the trick play stream is switched according to the time stamp value added to the trick play sync block during recording.
Output to 2. Also, the packetizer 104 for special reproduction
After outputting a predetermined amount of trick play stream, if the next trick play stream is not output within a predetermined time interval, the output of a playback image included in the trick play recording data stored in the memory 103 is output. PTS, which is time information for performing time management, is set to the P
Time after TS and PTS of next I picture
It rewrites to the previous value and retransmits the trick play stream with the updated PTS again. Hereinafter, a method of retransmitting the I picture data during the special reproduction will be described.

FIG. 17 is a diagram illustrating retransmission of I picture data in trick play packetizing section 104. In FIG. 17, FIG. 17A shows a case where it is not necessary to retransmit the previous I picture data, and FIG. 17B shows that the second I picture data I2 is not reproduced within the predetermined time interval T. A case where the previous I picture data I1 is retransmitted is shown.

In FIG. 17A, the first I picture data I1 is the first PTS shown in the PES header.
316 includes a value t1, and outputs I picture data I1 when the reference time reaches t1 during decoding. The second I picture data I2 includes the value t2 in the second PTS 317 shown in the PES header part, and outputs the I picture data I2 when the reference time reaches t2 at the time of decoding. After outputting the I picture data I1, the next second I picture data I2 is reproduced within a predetermined time interval T. The same applies to the third I picture data I3. On the other hand, as shown in FIG. 17B, the second I picture data I2
Is not reproduced within the predetermined time interval T due to, for example, the fact that the
After a predetermined time T after outputting the I picture data I1, the value t1 of the first PTS 316 of the first I picture data is changed to the predetermined value t2 'instead of the second I picture data I2.
Is retransmitted. The reason why the first I picture data I1 is not retransmitted as it is is that the value t1 of the first PTS 316 is already in the past with respect to the reference time when retransmitted, and the retransmitted I picture data I1 'is output. This is to prevent the I picture data I1 'to be retransmitted.
The value t2 'of the PTS 317 is rewritten.

PTS of I picture data I1 'to be retransmitted
Explaining the condition of the value t2 'of 317, the value t2' of the PTS 317 is t1 <t2 '<t3. Where PTS
Assuming that the value t2 'of 317 is t2'> t3, the second I picture data I2 is output when the reference time is t2 ', but the third PTS 318 which outputs the next third I picture data I3 is output. The value t3 is already in the past and the third
Will not be output. In order to prevent such a state from occurring, the value t of the PTS 317 is set.
It is necessary to satisfy the condition 2 '. Further, it is necessary that the I picture data I1 'to be retransmitted does not overlap with the next third I picture data I3. As an example of a method of eliminating the overlapping of the data, for example, a method of not outputting the third I picture data I3, or a method of changing the output of the third I picture data I3 to the timing at which the last data is output is set to the third A method of delaying the value in a range before the value t3 of the PTS 318, or a third PTS
A method of rewriting the value t3 of 318 to a time after t3 to delay the output of the third I-picture data I3 can be considered.

The value of the PTS may be normalized by a frame update cycle of a video output device (not shown). Further, the predetermined time interval T may be within 700 msec defined in the MPEG standard.

Referring to FIG. 16 again, during normal reproduction, sync block extraction unit 111 for normal reproduction inputs the data string reproduced by reproduction demodulation unit 92 and records the data for normal reproduction from the header of the sync block. A normal reproduction sync block is extracted by detecting and removing synchronization data, ID data, and error correction parity from information indicating the data, ie, a data sequence reproduced from the normal reproduction area in the recording track, Output to the normal reproduction packetizer 112. The normal reproduction packetizer 112 reconstructs the normal reproduction sync block output from the normal reproduction sync block extractor 111 into transport packet format data from the sync block format data, 12 is output.

The reproduction stream changeover switch section 12 includes a special reproduction stream output by the special reproduction packetization section 104, a normal reproduction stream output by the normal reproduction packetization section 112, and a normal reproduction / special reproduction mode signal indicating a reproduction state. 204, and selectively switches either stream according to the normal reproduction / special reproduction mode signal 204, so that the normal reproduction stream is output as the reproduction stream 203 during normal reproduction, and the special reproduction stream is reproduced during special reproduction. Output as stream 203.

As described above, according to the reproducing apparatus of the fifth embodiment of the present invention, at the time of the special reproduction, the time information recorded on the recording medium 202 for the special reproduction is reproduced at the predetermined interval. It is only necessary to reproduce and output the recording data for special reproduction including the information and the control information. Therefore, a circuit for newly generating time information and control information at the time of special reproduction is not required, and the circuit scale can be significantly reduced. Also,
After outputting the I picture data, if the next I picture data cannot be output within a predetermined time interval T, the PTS which is the time information relating to image output is replaced with the PTS of the previous I picture.
The same I picture data as the previous one rewritten to the value before the PTS of the next I picture data after the TS is output again. Thereby, it is possible to obtain a good special reproduction image without disturbance.

In the first to fifth embodiments, the recording device (first to fourth embodiments) and the reproducing device (fifth embodiment) are described as different configurations. Of course, the recording device and the reproducing device may be integrally configured.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a more detailed configuration of a recording data generating unit for trick play 2, a packet generating unit 3, and a recording unit 5 in FIG.

FIG. 3 is a diagram illustrating a relationship between a transport packet and a sync block.

FIG. 4 is a diagram illustrating extraction of an I-picture and reduction of a data amount.

FIG. 5 is a recording medium 2 for recording recording data for fast-forward reproduction.
FIG. 2 is a schematic diagram of a recording track on No. 02.

FIG. 6 shows a recording medium 20 for recording time information and control information.
FIG. 3 is a diagram illustrating an example of a predetermined position on a second position;

FIG. 7 is a diagram illustrating an example of a relationship between predetermined positions at which time information and control information are recorded on a recording medium 202.

FIG. 8 is a diagram for explaining a difference between a packet for generating recording data for normal reproduction and a packet for generating recording data for special reproduction.

FIG. 9 is a block diagram illustrating a configuration of a recording apparatus according to a second embodiment of the present invention.

FIG. 10 is a diagram showing an example of a relationship between a generated time stamp value and a trick play sync block number.

11 is a diagram showing an example in which image data for special reproduction is stored in a memory map in a memory 23. FIG.

FIG. 12 is a diagram showing an example of a recording position of recording data for 12 × speed special reproduction on a recording medium 202;

FIG. 13 is a block diagram illustrating a configuration of a recording apparatus according to a fourth embodiment of the present invention.

14 is a block diagram showing a detailed configuration of a DSM generation unit 27 and a memory 23 in FIG.

FIG. 15 is a diagram showing an example of the structure of a memory 23.

FIG. 16 is a block diagram illustrating a configuration of a playback device according to a fifth embodiment of the present invention.

FIG. 17 is a diagram for explaining retransmission of I picture data in the trick play packetizing section 104.

FIG. 18 is a schematic diagram showing the shape of a recording track on a magnetic tape and the trajectory of a head during special reproduction in a conventional recording / reproducing apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Recording data generation part for normal reproductions 2 ... Recording data generation part for special reproductions 3 ... Packet generation part 4 ... Control part 5 ... Recording part 6 ... Recording head 8 ... Reproduction head 9 ... Reproduction part 10 ... Special reproduction stream generation part DESCRIPTION OF SYMBOLS 11 ... Normal reproduction stream generation part 12 ... Reproduction stream changeover switch part 21 ... I picture extraction part 22 ... High frequency component deletion part 23,103 ... Memory 24 ... PES header rewriting part 25 ... Special reproduction sync block generation part 26 ... Time Stamp generation unit 27 DSM generation unit 31 Counter unit 32 PCR value generation unit 33 PTS generation unit 34 PCR packet generation unit 35 PSI packet generation unit 36 Null packet generation unit 37 Selector unit 51 Recording formatting unit 52: Recording modulation section 53: Recording amplifier 71: PES header analysis section 72: DS Trick mode flag setting unit 73 ... Trick mode field value insertion unit 91 ... Reproduction amplifier 92 ... Reproduction demodulation unit 101 ... Special reproduction sync block extraction unit 102 ... Reliability discrimination unit 104 ... Special reproduction packetization unit 111 ... Normal reproduction sync block extraction Unit 112: Normal reproduction packetizing unit 201: Bit stream 202: Recording medium (magnetic tape) 203: Reproduction stream 204: Normal reproduction / special reproduction mode signal 207, 304: I picture data 209: Special reproduction image data 301: Normal Reproduction areas 302, 303, 409, 410, 501... Special reproduction areas 305... PTS fields 306a to 306d, 308a to 308c. 02 ...... trajectory 313 ... PES packets 314 ... DSM trick mode flag 315 ... DSM trick mode field 316-318 ... PTS

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mutsuyuki Okayama 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Kenji Morimoto 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Atsushi Ochi 1006 Odama Kadoma, Kadoma City, Osaka Pref. Matsushita Electric Industrial Co., Ltd. 5C052 AA01 AB05 AC06 CC11 5C053 FA21 GA11 GA16 GB04 GB06 GB08 GB21 GB37 HA21 JA22 KA01 KA08 KA20 5D044 AB05 AB07 DE03 DE39 DE42 DE52 FG23 GK08 GK12

Claims (13)

[Claims] 1. A bit stream composed of a video signal and an audio signal encoded using correlation between screens,
A recording device for digital recording on a recording medium, comprising: a normal reproduction device for generating, from the input bit stream, recording data for normal reproduction used when performing normal reproduction including a plurality of predetermined recording blocks. Recording data generating means for performing a special reproduction for reproducing from the input bit stream at a speed different from the normal reproduction composed of a plurality of predetermined recording blocks (hereinafter referred to as special reproduction). Recording data for trick play to generate recording data by adding information output by the packet generating means; a time information packet indicating time information for managing output time of a playback image; And a control information packet indicating control information for decoding data, and outputting the control information packet to the trick play recording data generating means. Through a recording head, the normal reproduction recording data recorded on the normal reproduction area formed on the recording medium, and the special reproduction area recorded on the special reproduction area formed on the recording medium. Recording means for recording recording data for reproduction, wherein the time information packet and the control information packet output from the packet generation means are placed at a predetermined position in the special reproduction area in the format of the special reproduction recording data. A recording device for recording. 2. The method according to claim 1, wherein the predetermined position is provided on the recording medium such that the predetermined position is at least once within a predetermined time interval in synchronization with a scan of the recording head during special reproduction at a predetermined speed. The recording device according to claim 1, wherein the recording device is characterized in that: 3. The packet generating means generates the time information indicating a time reference value within a predetermined time interval, and a predetermined fixed value corresponding to a predetermined position in the special reproduction area for recording the time information. 3. The recording apparatus according to claim 1, wherein the time reference value is calculated by adding a value to the previous time information. 4. The time information for managing the output time of a reproduced image includes a time reference value serving as a reference of the time information and a data amount of special reproduction image data extracted from the input bit stream. The time information is a value after the time reference value at which the last data of the special reproduction image data is output, and a frame of the video display device that displays the special reproduction image data. The recording apparatus according to claim 1, wherein the recording apparatus is a value normalized based on an update cycle. 5. The time information to be added to the trick play recording data is a time stamp value required to output a trick play stream at a time interval input during recording during trick play, and Is a fixed value that is synchronized with a recording track on the recording medium and corresponds to a trick play sync block number indicated in header information of the predetermined plurality of recording blocks that constitute the trick play recording data. The recording device according to claim 1, wherein: 6. The control information necessary for decoding the bit stream composed of a video signal and an audio signal encoded using correlation between screens includes a configuration of the bit stream and the bit stream. Indicates an identification number for identifying the content of the data constituting, The control information for trick play recorded in the trick play area configured on the recording medium, the control information included in the input bit stream 6. The information according to claim 1, wherein the information is information indicating only the identification number corresponding to data extracted from the bit stream to generate the recording data for trick play, depending on control information. The recording device according to any one of the above. 7. The trick play recording data generating means,
The special reproduction image data extracted from the bit stream is stored in one memory in order, and the special reproduction image data stored in the memory is read out from the front (in the same direction as the storage order) to obtain a special fast forward reproduction special data. It is characterized in that the recording data for reproduction is generated, and the image data for special reproduction stored in the memory is read from the rear (in a direction opposite to the storage order) to generate the recording data for special reproduction for rewind reproduction. The recording apparatus according to claim 1. 8. The special reproduction recording data generation means, wherein the packet generation means further generates a Null packet which is invalid data in the MPEG standard, and the special reproduction image data stored in one of the memories. When generating the special playback recording data for fast-forward playback and rewind playback from the above, if each of the generated special playback recording data is less than a predetermined data amount, in order to compensate for the insufficient data The recording apparatus according to claim 7, wherein the special reproduction area is filled by inserting the Null packet output by the packet generation means into the special reproduction recording data. 9. The recording data generating means for special reproduction includes:
When generating the special reproduction recording data for fast-forward reproduction and rewind reproduction from the special reproduction image data stored in the two memories, each of the generated special reproduction recording data has a predetermined data amount. In the case where the number is less than the above, the special reproduction area is filled by inserting a dummy sync block, which is invalid data in the D-VHS standard, into the special reproduction recording data to compensate for the insufficient data. The recording device according to claim 7. 10. The input bit stream is MP
If the bit stream conforms to the EG standard, header analysis means for analyzing a PES header included in the input bit stream; and a DSM trick mode in the PES header indicating that the bit stream is data for special reproduction. DSM trick mode flag setting means for setting a flag to a predetermined value; storing special reproduction data extracted from the bit stream; and securing a 1-byte area for a trick mode field at a predetermined address in advance. By inserting a trick mode field at a predetermined position of the trick play data, a trick mode field is previously secured at a predetermined position in a PES header of the bit stream. Trick mode field 10. The recording apparatus according to claim 1, further comprising: a trick mode field value insertion unit for inserting predetermined data indicating a special reproduction condition into the recording medium. 11. The bit stream composed of a video signal and an audio signal encoded using a correlation between screens is encoded data according to the MPEG system. The recording device according to any one of claims 10 to 13. 12. A reproducing apparatus for digitally reproducing recording data from a recording medium on which recording data for normal reproduction and recording data for special reproduction are recorded, wherein the normal reproduction recorded on the recording medium is performed. Playback data for playing back the recording data for trick play and the trick play recording data via a playback head; and trick play stream generation means for generating a trick play stream from the trick play recording data played back by the playback unit. A normal reproduction stream generating means for reconstructing the normal reproduction recording data reproduced by the reproduction means and generating a normal reproduction stream; and reproducing either the normal reproduction stream or the special reproduction stream according to a reproduction mode. Switch means for switching whether or not to output as a stream, wherein the trick play stream generation means The N at the time of raw
After outputting the (N is a positive integer) trick play stream, if the subsequent (N + 1) th trick play stream cannot be output within a predetermined time interval, the playback image included in the Nth trick play stream The time information for performing the output time management is rewritten to a value after the time information of the Nth trick play stream and to a value before the time information of the succeeding (N + 2) th trick play stream. A reproducing apparatus, which outputs the data again. 13. The reproduction stream according to claim 1, wherein the reproduction stream is coded data according to an MPEG system.
3. The playback device according to 2.