JP2001160945A - Optical disk recorder suitable for seamless reproduction, reproducing device and recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical disk recorder, a reproducing device and a recording method that can readily realize seamless reproduction as to video objects recorded in real time, before and after each pause and discriminates whether seamless reproduction is available before the reproduction of the video objects. SOLUTION: Upon the receipt of a pause-release instruction, the optical disk recorder generates a video object which is generated immediately before it, a video object available of seamless reproduction and records them onto an optical disk. Furthermore, in the case that the video object and a video object immediately before are reproduced sequentially, a seamless flag SML- FLG denoting whether the seamless reproduction is available is generated and recorded in a VOB-TYPE in management information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a readable / writable optical disk, and a recording method and a reproducing method thereof. In particular,
A video object (compressed audio / video data) that can be played seamlessly even if the user performs a pause operation during recording
TECHNICAL FIELD The present invention relates to an optical disk recording device, a reproducing device, and a recording method for recording information.

[0002]

2. Description of the Related Art In recent years, an optical disk having a capacity of several GB has appeared in the field of a rewritable optical disk whose upper limit is about 650 MB. For example, a DVD-RAM (Digital
Video Disc-Random Access Memory). DVD-R
AM is expected as a recording medium for video and audio data (AV data: Audio Video data) in addition to the purpose of recording computer data. In other words, conventional typical AV data recording media and recording devices include magnetic tapes,
2. Description of the Related Art Video tape recorders (VTRs) have become widespread, and optical disks and optical disk recording / reproducing apparatuses are expected as alternatives.

An optical disk recording / reproducing apparatus used as a replacement for a stationary VTR receives a television broadcast, converts the received television signal into a video object, and records the video object on a DVD-RAM. More specifically,
The optical disk recording / reproducing apparatus generates compressed video data (video elementary stream) and compressed audio data (audio elementary stream) from a television signal and converts the compressed video data and compressed audio data into fixed-length video packs and audio packs, respectively. And interleave them, and record them as video objects on the optical disc. Here, the video elementary stream and the audio elementary stream are generated according to the MPEG (ISO / IEC13818) standard.

Normally, one video object is generated by one continuous recording in an optical disk recording / reproducing apparatus. Therefore, during the period from the user's recording start instruction to the recording end instruction, the optical disc recording / reproducing apparatus generates and records one video object.

[0005]

However, according to the conventional optical disk recording / reproducing apparatus, when a pause (pause of recording) occurs during recording, there is a problem that seamless reproduction of a video object cannot be easily realized. is there. More specifically, when one video object is generated by one continuous recording, the optical disc recording / reproducing apparatus completes the video object by a pause instruction and records a new video object by a pause release instruction. Will be. . In other words, from the recording start instruction to the pause instruction, from the pause release to the pause instruction,
In each period from the pause release to the recording end operation, each video object is recorded as one video object.

In this case, if the video object recorded up to the pause instruction and the next video object recorded after the pause release are reproduced in order, seamless reproduction cannot be guaranteed, and the following problem may occur. . First, in the optical disc recording / reproducing apparatus, during encoding of video data, the video elementary stream is stored in a buffer assuming a video virtual buffer so that the video elementary stream does not overflow or underflow in the video input buffer of the reproducing apparatus. To simulate the data size. The encoding of the audio data is similarly simulated by assuming an audio virtual buffer. Although continuous playback of a single video object can be performed seamlessly by these, when playback is switched to a new video object due to a pause, overflow and underflow in the playback device may occur.

In view of the above problems, an object of the present invention is to provide an optical disk recording apparatus, an optical disk reproducing apparatus, and an optical disk recording method for easily realizing seamless reproduction of a video object recorded in real time before and after a pause. . It is another object of the present invention to provide an optical disk recording apparatus, an optical disk reproducing apparatus, and an optical disk recording method that can determine whether seamless reproduction is possible before reproducing a video object.

[0008]

An optical disk recording apparatus for solving the above-mentioned problems includes a receiving means for receiving a user operation including a recording start instruction, a recording end instruction, a pause instruction and a pause release instruction, a recording start instruction or a pause release instruction. From, until a pause instruction or recording end instruction is accepted,
Encoding means for generating one video object by compressing and encoding the audio / video data, and generating a video object which can be seamlessly reproduced with the video object generated immediately before when a pause release instruction is received; Each time a video object is created,
Generating means for generating a seamless flag indicating whether seamless playback is possible when the video object and the immediately preceding video object are played back in sequence; a video object generated by the encoding means; and a seamless flag generated by the generating means. Recording means for recording the information on an optical disc.

Here, the seamlessly reproducible video object is included in the seamlessly reproducible video object without causing overflow and underflow in a video buffer in a reproducing apparatus for temporarily storing compressed video data. The compressed video data is input to the video buffer in the playback device following the immediately preceding video object.

If the seamless flag indicates that seamless playback is possible, the decoder in the playback device starts playback of the video object without resetting the internal state of the decoder after completion of playback of the immediately preceding video object. In this case, the generation unit may transmit, from the encoding unit, the last system clock reference value of the video object whose generation has been completed by the pause instruction and the first system clock reference value of the video object whose generation has been started by the pause release instruction. Acquired,
The recording means may be configured to record the last system clock reference value, the first system clock reference value, and the seamless flag as video object information on an optical disc.

[0011] According to this configuration, the reproducing apparatus can smoothly perform special reproduction such as reverse reproduction by referring to the system clock reference in the video object information before reproducing the video object. Here, the encoding means replaces the compressed audio data with the audio data divided by the pause instruction and the pause release by replacing a period immediately before or immediately after the division and shorter than the audio frame with silent data. You may comprise so that it may generate | occur | produce.

An optical disc reproducing apparatus according to the present invention is a reproducing apparatus for reproducing a video object recorded on an optical disc, wherein the optical disc stores a plurality of video objects and a plurality of pieces of video object information. The object includes compressed video data and compressed audio data, and the video object information includes:
The optical disc playback device corresponds to a video object and includes a seamless flag, wherein the seamless flag indicates whether seamless playback is possible when the corresponding video object and the preceding video object are played back in sequence. Reading means for reading information and a video object corresponding thereto, decoding means for generating audiovisual data by decoding the video object read by the reading means, and video object information read by the reading means And control means for controlling seamless playback by the decoding means based on the seamless flag in.

Here, the decoding means is provided with a separating means for separating the video object read by the reading means into compressed video data and compressed audio data, and a video buffer for temporarily holding the separated compressed video data. An audio buffer for temporarily holding the separated compressed audio data, a first decoder for decoding compressed video data in a video buffer, and a second decoder for decoding compressed audio data in a video buffer. When the seamless flag corresponding to the video object to be reproduced next indicates that seamless reproduction is possible, the read means can be used without initializing the video buffer and the audio buffer when switching from the current video object to the next video object. Next video object read to Transfected may be controlled so as to supply to the decoding means.

Also, the optical disk recording method of the present invention includes a receiving step of receiving a user operation including a recording start instruction, a recording end instruction, a pause instruction, and a pause release instruction, and a pause instruction or recording from a recording start instruction or a pause release instruction. Until the end instruction is received, one video object is generated by compressing and encoding the audiovisual data, and when the pause release instruction is received, seamless playback with the video object generated immediately before is possible. Encoding step for generating a video object, a first recording step for recording the video object generated by the encoding means on an optical disc, and each time a video object is generated, the video object and the immediately preceding video object are sequentially reproduced. Seamless playback if possible Either have if a generation step of generating a video object information including the seamless flag indicating whether, and a second recording step of recording the video object information generated on the optical disk by the generating means.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (1) Outline of Optical Disc Recording / Reproducing Apparatus Optical disc recording / reproducing apparatus 1 according to an embodiment of the present invention.
Is for replacing a stationary VTR. As shown in FIG. 1, the optical disk recording / reproducing apparatus is connected to an antenna (not shown) and a television receiver 2, and receives a television signal received from the antenna or a video / audio signal included in a video signal input from an input terminal. Is compressed and encoded to obtain compressed video and audio data (hereinafter referred to as a video object; VOB).
Is generated in real time and recorded on the optical disk, and the VOB recorded on the optical disk is reproduced.

This optical disk recording / reproducing apparatus generates one video object in real time during a period from a recording start instruction or a pause release instruction by a user until a pause instruction or a recording end instruction is accepted. Two video objects generated before and after the pause release instruction are generated so as to ensure seamless reproduction, and are recorded on the optical disc. Further, each time a video object is generated, a seamless flag and seamless information are generated and recorded on the optical disc as management information.

Here, the seamless flag is a flag indicating whether seamless reproduction is possible or not. Seamless information consists of the last SCR (System
Clock Reference) and the first SCR of the video object. The seamless flag and the seamless information are referred to at the time of reproduction. (2) Configuration of Optical Disc (2.1) Physical Configuration of Optical Disc The optical disc in the embodiment of the present invention is a DVD-RA
M will be described as an example. The physical configuration of a DVD-RAM is disclosed in detail in JP-A-8-7282, which discloses a method of recording data on both lands and groups, and JP-A-7-93873, which discloses a zone CLV (constant linear velocity). And will not be described in detail here.

(2.2) Logical Configuration of Optical Disk (DVD-RAM) FIG. 2 shows an outline of a lead-in area, a data area, and a lead-out area provided in an area of the optical disk, and an outline of a file configuration recorded in the data area. FIG. In the same figure, the lead-in area is at the beginning (the innermost part)
A reference signal necessary for stabilizing the servo control in the optical disk recording / reproducing apparatus, an identification signal with another medium, and the like are recorded in the. Following the lead-in area is a data area. In the data area, a file storing VOBs and management information is recorded. A lead-out area exists at the end (outermost periphery). In this area, the same reference signal as that in the lead-in area is recorded.

At the beginning of the data area, information for a file system called volume information is recorded. Since the file system is publicly known, its description is omitted. FIG. 1 shows a configuration example of directories and files read and written through a file system. In this file configuration, a DV for storing all the files handled by the optical disc recording / reproducing apparatus immediately below the ROOT directory.
A D_RTAV (DVD_Real Time Audio Visual) directory is provided. The files stored in the DVD_RTAV directory include one management information file and V
It is roughly classified into two types of one or more AV files for OB recording.

In the figure, VR_VR_
MANGR. If the I / O is an AV file, VR_M
OVIE. VRO is shown. VR_MOVIE.
The VRO includes a video (including audio) recording, ie, one or more video objects. (2.2.1) AV File FIG. 3 shows the VR_MOVIE. FIG. 4 is a diagram illustrating a data configuration of a VRO file.

As shown in the figure, VR_MOVIE. VR
In the O file, VOBs # 1 to #N are arranged. N is 1
That is the number above. Each VOB is composed of a plurality of VOBUs. VOBU conforms to the MPEG video standard ISO / IEC (1381
At least one GOP (Group Of POP) defined in 8-2)
picture) and a fixed-size (2 kbytes) packed sequence. The video pack (V_PC)
K), an audio pack (A_PCK), and the like.

V_PCK includes video data. A_
PCK includes audio data. Audio data is MPEG audio, Dolby (registered trademark) AC
3. Data encoded by linear PCM or the like.
V_PCK and A_PCK are interleaved in the VOBU. Each pack has an S time stamp.
CR, DTS (Decode Time Stamp), PTS (Presentati
on Time Stamp). The SCR indicates the time at which the pack should be taken out of the track buffer and input to the video buffer during playback. The DTS indicates the time at which the data of the pack should be taken out of the video buffer and input to the video decoder. The PTS indicates the time at which the decoded data of the pack should be displayed or audio output. However, since the decoding processing time for audio data can be ignored compared to the decoding processing time for video data, the PTS also serves as the DTS in the audio pack.

(2.2.2) Management File FIG. 4 shows the management information file VR_MANG shown in FIG.
R. FIG. 3 is a diagram hierarchically showing a data structure of an IFO. As shown in the figure, VR_MANGR. IFO is RTR_VMG
(Real Time Recording_Video Manager), a VOB STI (stream information) table, a VOBI (VOB Information) table, and a PG
CI (program chain information) table.

The VOB_STI table contains "VOB stream information (VOB_STI in the figure)" corresponding to VOBs one-to-one or one-to-one. The VOB stream information includes video attributes and audio attributes of the VOB. VO
The BI table stores VOB information (VOB information) in this table.
"Number of VOBI's" indicating the total number of I)
And “VOBI # 1 to #N”. N is indicated by the VOBI number.

The VOB information is information relating to a VOB corresponding to the VOB on a one-to-one basis, and includes "VOB type (VOB_typ)".
e) ”,“ Seamless Information (SMLI) ”,“ VOB Start PTM ”
(VOB_start_Presentation_time) ”,“ VOB end PT
M (VOB_end_Presentation_time) ”,“ VOB recording time
(VOB_REC_TIME) "," VOB stream information number (VOB_S
TIN) "and" Time Map Information (TMAPI) ".

The VOB type (VOB_type) is the corresponding VO
When B is played back in sequence with the immediately preceding VOB, a “seamless flag (SML_FL
G) ”. The seamless flag is applied to the video object generated by the user's pause release instruction.
1 (seamless playback possible) is set, and the video object generated by the user's recording start instruction
0 "(not necessarily seamless playback) is set.

The seamless information (SMLI) is effective when the seamless flag is "1", and is seamless information including the last SCR (PREV_VOB_LAST_SCR) of the immediately preceding VOB and the first SCR of the present video object. is there.
These SCRs can be used at the time of video object switching in fast forward playback, reverse playback, and the like.

VOB start PTM (VOB_start_PTM), VO
The B end PTM (VOB_end_PTM) indicates the start time and end time of the VOB presentation (display and audio output), respectively. VOB recording time (VOB_REC_TIME) is VO
B shows the recording time. VOB stream information number (VOB_S
(TIN) is the number of VOB stream information corresponding to the video object.

The time map information (TMAPI) includes a time map in which the reproduction time of the VOB and the recording position of the optical disc are associated in VOBU units. Also, the PGCI table is
It is a table in which program chain information (PGCI) indicating the reproduction order of VOBs or the reproduction order of an arbitrary reproduction section of VOB is loaded. The PGCI # 1 in the figure includes cell information (CellI # 1 to CellI # J). Each cell has VOB_
An arbitrary playback section of the VOB specified by the ID is set to the start time (C
ell_Start_PTM) and end time (Cell_End_PTM). Each playback section of the VOB represented by cells # 1 to #J is played back in the cell arrangement order.

For example, in the optical disk recording / reproducing apparatus, VOBs # 1 and # 3 are generated by a series of operations such as recording start, pause instruction, pause release instruction, and recording end by the user.
When PGCI # 2 is generated, the following PGCI # 1 is generated. PGCI # 1 is the playback time (V
OB_Start_PTM), cell information (CellI # 1) having the same value as the last playback time (VOB_End_PTM), respectively, and the first playback time (VOB_St) of VOB # 2.
art_PTM), the same value as the last playback time (VOB_End_PTM), Cel
Cell information for l_Start_PTM and Cell_End_PTM (CellI # 2)
including. In other words, the PGC # 1 sets the reproduction order of all sections of VOB # 2 next to all sections of VOB # 1.

In this case, since VOBs # 1 and # 2 are video objects before and after pause and pause release,
In the VOB information (VOBI # 2) of VOB # 2, the seamless flag is set to "1", and more effective seamless information is set. (3) Optical Disk Recording / Reproducing Apparatus FIG. 5 is a block diagram showing a configuration of a main part of the optical disk recording / reproducing apparatus shown in FIG.

As shown in FIG.
User interface unit 101, system control unit 10
2, input unit 103, encoder unit 104, output unit 10
5, a decoder unit 106, a track buffer 107, and a drive 108. The user interface unit (U / I in the figure) 101 has an operation panel and a remote control light receiving unit, and receives a user operation from the operation panel and a user operation from the remote control as shown in FIG. The user operation includes instructions such as recording start, recording end, pause, pause release, reproduction, and the like.

When the system control unit 102 receives a recording start, recording end, pause, and pause release instruction from the user interface unit 101, the system control unit 102 notifies the encoder unit 104 of the fact, and receives a reproduction start and reproduction end instruction. In this case, the fact is notified to the decoder unit 106. More specifically, the system control unit 102 notifies the encoder unit 104 of the start of recording, thereby causing the encoder unit 104 to start generating a new video object.

The system control unit 102 includes the encoder unit 1
04 by notifying the end of recording to the encoder unit 10.
Then, based on the encoding information obtained from the encoder 104, VOBI and VOB_STI of the generated video object are generated and recorded on the optical disk. The encoding information here indicates whether seamless reproduction is possible, and if possible, the last SCR (PREV_PREV_
VOB_LAST_SCR) and the value of the first SCR (VOB_FIRST_SCR) of the video object that has been generated.

The system control unit 102 notifies the encoder unit 104 of a pause instruction, thereby causing the encoder unit 104 to complete the generation of the video object and save the internal state (that is, do not reset). Further, VOBI and VOB_STI are generated based on the encoding information from the encoder unit 104, and are recorded on the optical disc.

The system control unit 102 includes the encoder unit 1
By notifying the pause release to 04, the internal state stored in the encoder unit 104 is set as an initial state, and the encoder unit 104 is started to generate a new video object. In this case, since the encoder unit 104 takes over the last internal state in which the generation of the immediately preceding video object has been completed, the video object whose generation has newly started can be seamlessly reproduced.

The input unit 103 outputs video data and audio data obtained by demodulating a broadcast signal to the encoder unit 104. The encoder unit 104
By compressing the video signal and the audio signal input from the input unit 103 under the control of the system control unit 102, V
_PCK and VOB composed of A_PCK are generated. When receiving the notification of the pause instruction, the encoder unit 104 completes the generation of the video object and saves the internal state without resetting. When the notification of the pause release is received, the encoder unit 104 sets the saved internal state as an initial state. Start creating a video object (that is, taking over the internal state).

The track buffer 107 temporarily stores the VOB generated by the encoder unit 104 during recording, and stores the VOB read from the DVD-RAM during reproduction.
B is temporarily stored. The drive 108 is a DVD-R
Servo control and rotation control are performed during recording / reproduction by mounting the AM, VOBs stored in the track buffer 107 are written to the DVD-RAM through the optical pickup, and VOBs recorded in the DVD-RAM are written through the optical pickup. And read it into the track buffer 107. Reading / writing to / from the DVD-RAM is actually performed in units of ECC (Error Correcting Code) blocks (16 sectors = 2 Kbytes × 16 packs).

The decoder unit 106 includes the system control unit 10
Under the control of 2, the VOB read from the DVD-RAM and input through the track buffer 107 is expanded to generate a video signal and an audio signal. The output unit 105 converts a video signal and an audio signal input from the decoder unit 106 from digital to analog, and outputs the digital and analog signals to a television receiver or the like.

(3.1) Encoding Unit FIG. 6 is a block diagram showing a detailed configuration of the encoder unit 104 in FIG. As shown in FIG.
Includes a video encoder 1501, buffer 1502, audio encoder 1503, audio encode buffer 1504, control information buffer 1505, system time clock unit (abbreviated as STC unit) 1506, encoder control unit 1507, and system encoder 1508. Also, the system encoder 1508 includes a virtual playback time counting unit 1601, a video packing unit 1602, a virtual decoder buffer 1603, an audio packing unit 1604, and a virtual decoder buffer 1605.

The video encoder 1501 has a video input buffer (not shown) inside, fetches video data input from the input unit 103 into the input buffer, and encodes the video data in the input buffer according to the MPEG2 standard. Then, the compressed video data is stored in the video encode buffer 1502. Audio encoder 1
Reference numeral 503 includes an audio input buffer (not shown) therein, takes in audio data input from the input unit 103 into the input buffer, encodes (compresses) the audio data in the input buffer, and stores the compressed audio data in the audio encode buffer 1504. Is stored.

The STC unit 1506 generates a clock signal (system time clock) which is the basis of the encoding operation. The encoder control unit 1507 includes the encoder unit 1
04 controls the entire encoding operation. The encoding operation is started according to the notification of recording start or pause release from the system control unit 102, and ends the video object according to the recording end or pause notification. However, when the notification of the pause and the notification of the release of the pause are received, the encoding operation is performed before and after the pause by taking over the internal state.

Specifically, when the recording start is notified, the encoder control unit 1507 causes the video encoder 150 to start generating a new video object.
1. The audio encoder 1503 and the system encoder 1508 are controlled. In this case, the encoder 104
Each of the buffers may be reset to an initial state.

When the recording end is notified, the encoder control unit 1507 controls the video encoder 1501, the audio encoder 1503, and the system encoder 1508 so as to complete the generation of the video object.
In this case, various buffers in the encoder unit 104 may be reset after the generation of the video object is completed.

When the pause is notified, the encoder control unit 1507 controls the video encoder 1501, the audio encoder 1503, and the system encoder 1508 so as to complete the generation of the video object. , The audio encoding buffer 1504 and the virtual decoder buffers 1603 and 1605 are controlled to be retained without resetting. Thereby, the encoder unit 1
04 is stored.

When receiving a pause release instruction, the encoder control unit 1507 causes the video encoder 150 to start generating a new video object with the internal state stored in the encoder unit 104 as an initial state.
1. The audio encoder 1503 and the system encoder 1508 are controlled. As a result, a video object that can be seamlessly reproduced is generated.

The encoder control unit 1507 adjusts the compression ratio of the video encode buffer 1502 according to the occupancy of the virtual decoder buffers 1603 and 1605. This adjustment is made so that the video and audio buffers in the decoder do not overflow and underflow during playback. The system encoder 1508 controls the video encoding buffer 15
02. Compressed video data and compressed audio data corresponding to the pack size of the pack (or packet) are respectively extracted from the audio encode buffer 1504, V_PCK and A_PCK are created, and the created packs are interleaved to sequentially create VOBUs. , To the track buffer 1407.

(3.1.1) System Encoder In the system encoder 1508 of FIG. 6, the virtual reproduction time counting section 1601 generates the S generated by the STC section 1506.
Based on TC, a time stamp (SCR, DTS (Decode Time Stamp), PTS (Pre
sentation TimeStamp) is generated as a reference time (virtual reproduction time). Here, the DTS is a time stamp indicating the time at which the decoder unit 106 starts decoding in the reproducing operation, and the PTS is a time stamp indicating the time at which the video data or audio data decoded in the reproducing operation is displayed or outputted.

The video packing unit 1602 extracts compressed video data from the video encoding buffer 1502, and V_PC on which the extracted compressed video data is loaded.
K are sequentially generated. At this time, the time stamp is determined so as not to cause overflow and underflow in the virtual decoder buffer 1603. The virtual decoder buffer 1603 is a virtual buffer for simulating the data occupancy of a buffer (that is, a video buffer in the decoder) that temporarily stores compressed video data during a playback operation.

The compressed audio data is extracted from the audio packing unit 1604 and the audio encode buffer 1504, and A_PCK on which the extracted compressed audio data is loaded is sequentially generated. At this time, the time stamp is determined so that overflow and underflow do not occur in the virtual decoder buffer 1605.

The virtual decoder buffer 1605 is a virtual buffer for simulating the data occupancy of a buffer (that is, an audio buffer in the decoder) that temporarily holds compressed audio data during a reproducing operation. The interleave unit 1607 sequentially takes out the packs having the smallest SCR value from the packs generated by the video packing unit 1602 and the audio packing unit 1604, and stores a pack sequence arranged in the order in which the packs are taken out in the track buffer 1407. Output to

(4) Recording Operation Before and After Pause FIG. 7 is a flowchart showing details of the pause processing by the encoder control unit 1507. The pause process of FIG. 7 will be described with an explanatory diagram showing the internal operation before and after the pause of the encoder unit 104 shown in FIG. As shown in FIG. 7, when the pause is notified from the system control unit 102 during the recording operation, the encoder control unit 1507 first converts the video data input from the input unit 103 to the input buffer in the video encoder 1501 into a picture break. Stop at
The input of audio data from the input unit 103 to the input buffer in the audio encoder 1503 is stopped (step 71), and the encoding operation of the audio encoder 1503 is stopped at a break between audio frames (step 72).

In FIG. 9, at this point, the audio encoder 1503 outputs the audio frame f3 of the input buffer.
Is encoded into the compressed audio data a3,
Stop the encoding operation. As a result, the input buffer in the audio encoder 1503 holds the audio frame f4 and a part up to the part f51 of the audio frame.
4, compressed audio data... A1, a2, a3
Is held up.

On the other hand, at this point, the video encoder 150
1, the picture data B8, B9
Is held up. In this state, video encoder 1
501 completes the encoding of the video data held in the input buffer. In FIG. 9, the video encoder 1501 completes encoding of pictures P9, B7, and B8.

When the encoding of the picture data remaining in the input buffer by the video encoder 1501 is completed (step 73), the encoder control unit 1507 stops the encoding operation of the video encoder 1501 (step 74). The compressed video data encoded until the video encoder 1501 stops is temporarily stored in the video encode buffer 1502. The system encoder 1508 controls the video encoding buffer 1
Until 502 becomes empty, the video encode buffer 15
The compressed video data is extracted from the data 02 and multiplexed with the compressed audio data as a video object.

The encoder control unit 1507 determines that the video encoding buffer 1502 has become empty (step 7).
5) The operation of the system encoder 1508 is stopped (step 76). Thus, the generation of the video object is completed. The encoder control unit 1507 holds the state without resetting various buffers thereafter (step 77), and notifies the system control unit 102 of the encoding information of the video object that has been generated (step 78). The various buffers mentioned here are
(A) an input buffer in the video encoder 1501;
(B) video encode buffer 1502, (c) virtual decoder buffer 1603, (d) input buffer in audio encoder 1503, (e) audio encode buffer 1504, (f) virtual decoder buffer 1
605.

In FIG. 9, the system encoder 1508
(A) and (b) are empty, (c) and (f) hold the occupancy, and (d)
Shows a state in which the audio frame data f4 and a part f51 of the audio frame are held, and (e) shows a state in which the compressed audio frame data a1, a2, and a3 are held. This state continues until a pause release is notified.

FIG. 8 is a flowchart showing details of the pause release processing by the encoder control unit 1507. As shown in the figure, the encoder control unit 1507 receives the pause release notification from the system control unit 102 in the paused state without resetting the various buffers (disable reset signals to the various buffers). In the stored state (step 81), video data input from the input unit 103 to the input buffer in the video encoder 1501 and audio data input from the input unit 103 to the input buffer in the audio encoder 1503 are restarted ( Step 82), and the encoding operation of the video encoder 1501, the audio encoder 1503, and the system encoder 1508 is restarted (step 83).

After the encoding operation is resumed, the audio encoder 1503 encodes the uncorrelated audio frames while suppressing the audio level (step 8).
4). In the case of FIG. 9, the audio frame having no correlation is an audio frame composed of f51 and f52 whose continuity is lost due to the pause. For example, the audio encoder 1503 performs encoding after replacing all of the audio frames composed of f51 and f52 or one of f51 and f52 with silent data. As a result, the audio level of the audio frame for which the correlation is lost due to the pause is suppressed, so that it is possible to eliminate the generation of noise (pop noise) during reproduction.

As described above, the generation of a new video object is started by taking over the state at the time of the pause. Further, the encoder control unit 1507 generates and holds a seamless flag and seamless information as a part of the encoding information to be notified when the new video object is completed (step 85).

In FIG. 9, the above (d) is canceled by releasing the pause.
The audio frame data f4 and a part f51 of the audio frame in the
, And the compressed audio frame data a1, a2, and a3 in (e) are interleaved by the system encoder 1508 into the video object. The encoding operations of the video encoder 1501 and the audio encoder 1503 are as follows.
Since the compression rate is controlled by the encoder control unit 1507 with the occupancy stored in the (c) virtual decoder buffer 1603 and the (d) virtual decoder buffer 1605 as the initial value, the newly generated video object is Can be seamlessly reproduced for the video object.

(5) Decoder Unit FIG. 10 is a block diagram showing a detailed configuration of the decoder unit 106 in FIG. As shown in FIG.
Is a demultiplexer 1702, a video buffer 170
3. Video decoder 1704, reorder buffer 170
5, switch 1706, audio buffer 1707,
Audio decoder 1708, control information output unit 1709
Is provided.

The demultiplexer 1702 receives a VOB from the track buffer 1407 at the time of a reproducing operation, and sequentially stores the payload (packet) of the pack in the video buffer 1703 and the audio buffer 1707 according to the type of each pack in the VOB. Video buffer 1
703, storage in the audio buffer 1707 is performed when the SCR in the pack matches the STC.

The video decoder 1704 takes out a packet from the video buffer 1703 and decodes it. The packet is extracted when the DTS (PTS in the case of an audio packet) described in the first packet in the video buffer 1703 matches the STC. The reorder buffer 1705 is a buffer for changing the output order of the decoded data from the coding order to the display order on a picture basis.

The switch 1706 is connected to the video decoder 17
04 and the switch 1706 to output decoded data to the output unit 1405 in picture units. This output is performed when the PTS described in the packet matches the STC. The audio decoder 1708 takes out the packet from the audio buffer 1707 and decodes it. The packet is fetched by the audio buffer 1707.
This is performed when the PTS described in the first packet in the table matches the STC. The decoding result is immediately output to the output unit 140
5 is output.

(5.1) Playback Operation Upon receiving a playback start instruction, the system control unit 102 refers to the PGCI shown in FIG. 4 and instructs the decoder unit 106 to play back the video object indicated by the cell information. For example, if the PGCI includes all of VOB # 1 and VOB # 2
Are designated in order as the reproduction path, the system control unit 102 first notifies the decoder unit 106 of a reproduction instruction of VOB # 1, and immediately before the reproduction is completed,
The reproduction instruction of # 2 is notified to the decoder unit 106.

Prior to the notification of the reproduction instruction, the system control unit 102 refers to the VOBI corresponding to the video object to be reproduced, and if the seamless flag included in the VOBI is "0", initializes the decoder unit 106. Then, if the seamless flag included in the VOBI is “1” and another video object is already being reproduced, the reproduction start is notified without initializing the decoder unit 106. The initialization here means resetting the video buffer 1703, the audio buffer 1707, and the reorder buffer 1705.

When the seamless flag is "1", the system control unit 102, after the notification of the reproduction start, outputs the
In 06, the control is performed so that the video object to be reproduced is supplied in a state where the above-mentioned reset has not been performed since the end of the immediately preceding video object is input. As a result, the decoder unit 106 plays back seamlessly when the video object is switched.

The above reproduction indicates reproduction at a normal speed. When performing special playback such as fast-forward playback or rewind playback, the system control unit 102
Then, special playback is realized by partially playing back (for example, only I pictures) in VOBU units. At this time, the seamless information in the case where the seamless flag is “1” can be used in trick play. For example, in rewind reproduction, the STC of the decoder unit 106 can be switched before reading the immediately preceding VOB by referring to the last SCR of the immediately preceding VOB.

(6) Others In the above embodiment, the stationary optical disk recording / reproducing apparatus has been described as an example, but a portable video camera (cam recorder) may be used. In this case, the input unit 103 includes a microphone and a camera, and the output unit 105 includes a small liquid crystal panel and a small speaker.

Although the DVD-RAM has been described as an example of the optical disk, other writable optical disks may be used. Alternatively, the recording may be performed on a hard disk instead of the optical disk. In the operation example shown in FIG. 9, the audio encoder 1503 stops the encoding operation while leaving the audio data f4 and f51 in the internal input buffer. However, the encoding operation is performed after the audio data f4 in the input buffer is encoded. May be stopped. In this case, after the pause instruction, only data less than one audio frame remains in the input buffer, and the audio encoding buffer 1504 also holds the compressed audio data encoded for the audio frame f4. Become.

In the above embodiment, in order to suppress the level of audio frames (for example, f51 and f52 in FIG. 9) that have been separated due to pauses and have no correlation, the audio encoder 1503 uses one of the separated audio data or Both are replaced with silent data before encoding. Alternatively, the following may be performed. That is, the input unit 103 and the audio encoder 1
A mute circuit is added during the period 503 to mute for a period shorter than the audio frame (for example, several mS) from the time when the encoding operation of the audio encode buffer 1504 is restarted by releasing the pause. In this case, the mute circuit inputs silent data to the audio encoder 1503 during the above period. As a result, the audio frame divided by the pause does not generate noise (pop noise) during reproduction.

The mute circuit may be configured to mute the audio encoder 1503 in a short period from immediately before the stop of the encoding operation to the stop by the pause instruction. Alternatively, the mute may be performed both immediately before stopping the encoding operation and immediately after resuming the encoding operation.

[0074]

According to the optical disk recording apparatus of the present invention, a receiving means for receiving a user operation including a recording start instruction, a recording end instruction, a pause instruction, and a pause release instruction, and a pause instruction or recording from a recording start instruction or a pause release instruction are provided. Until the end instruction is received, one video object is generated by compressing and encoding the audiovisual data, and when the pause release instruction is received, seamless playback with the video object generated immediately before is possible. Encoding means for generating a simple video object; and generating means for generating a seamless flag indicating whether seamless reproduction is possible when the video object and the immediately preceding video object are reproduced in order each time a video object is generated. , The video object generated by the encoding means The seamless flag generated by the generating means and recording means for recording on the optical disk.

Here, the seamlessly reproducible video object is included in the seamlessly reproducible video object without causing overflow and underflow in a video buffer in a reproducing apparatus for temporarily storing compressed video data. The compressed video data is input to the video buffer in the playback device following the immediately preceding video object.

If the seamless flag indicates that seamless playback is possible, the decoder in the playback device starts playback of the video object without resetting the decoder internal state after completion of playback of the immediately preceding video object. According to this configuration, a user's pause instruction made during recording and video objects generated before and after the pause release can be recorded in real time so that seamless reproduction is possible.
It is possible to determine whether seamless reproduction is possible by referring to the seamless flag before reproducing the video object.

Here, the generation means calculates the last system clock reference value of the video object whose generation has been completed by the pause instruction and the first system clock reference value of the video object whose generation has been started by the pause release instruction. Obtained from encoding means,
The recording means may be configured to record the last system clock reference value, the first system clock reference value, and the seamless flag as video object information on an optical disc.

According to this configuration, the reproducing apparatus can smoothly perform special reproduction such as reverse reproduction by referring to the system clock reference in the video object information before reproducing the video object. Here, the encoding means replaces the compressed audio data with the audio data divided by the pause instruction and the pause release by replacing a period immediately before or immediately after the division and shorter than the audio frame with silent data. You may comprise so that it may generate | occur | produce.

According to this configuration, the encoding means generates compressed audio data after replacing the period with silent data, so that uncorrelated data is continuously mixed in the audio frame divided by the pause. Therefore, noise at the time of reproduction can be eliminated. Also, the optical disc reproducing apparatus of the present invention is a reproducing apparatus for reproducing a video object recorded on an optical disc, wherein the optical disc records a plurality of video objects and a plurality of pieces of video object information, and the video object is compressed. The video object information includes video data and compressed audio data,
The optical disc playback device corresponds to a video object and includes a seamless flag, wherein the seamless flag indicates whether seamless playback is possible when the corresponding video object and the preceding video object are played back in sequence. Reading means for reading information and a video object corresponding thereto, decoding means for generating audiovisual data by decoding the video object read by the reading means, and video object information read by the reading means And control means for controlling seamless playback by the decoding means based on the seamless flag in.

According to this configuration, it is possible to determine whether seamless reproduction is possible by referring to the seamless flag before reproducing the video object. Here, the decoding means includes a separating means for separating the video object read by the reading means into compressed video data and compressed audio data; a video buffer for temporarily holding the separated compressed video data; An audio buffer for temporarily storing the compressed audio data, a first decoder for decoding the compressed video data in the video buffer, and a second decoder for decoding the compressed audio data in the video buffer. When the seamless flag corresponding to the video object to be reproduced next indicates that seamless reproduction is possible, when switching from the current video object to the next video object, the video buffer and the audio buffer are read out to the reading means without initializing. The next video object It may be controlled so as to supply the de means.

According to this configuration, when it is determined that seamless reproduction is possible, when the video object is switched, the video buffer and the audio buffer are reproduced without initialization, so that seamless reproduction can be easily performed. . Here, the video object information includes a seamless flag, a last system clock reference value of a preceding video object, and a first system clock reference value of a corresponding video object. If the possibility is indicated, the system time clock inside the decoding means may be controlled to be switched according to the last system clock reference value of the corresponding video object and the first system clock reference value of the corresponding video object.

According to this configuration, by referring to the system clock reference in the video object information before reproducing the video object, special reproduction such as reverse reproduction between the video objects can be smoothly performed. . Further, the optical disc recording method of the present invention includes a recording start instruction, a recording end instruction, a pause instruction,
A video object by compressing and encoding audiovisual data during a receiving step of receiving a user operation including a pause release instruction, and during a period from a recording start instruction or a pause release instruction until a pause instruction or a recording end instruction is received. Encoding step for generating a video object that can be seamlessly reproduced with a video object generated immediately before the pause instruction is received, and a video object generated by the encoding unit that is recorded on an optical disc. (1) a recording step; and a generating step of generating, every time a video object is generated, video object information including a seamless flag indicating whether seamless reproduction is possible when the video object and the immediately preceding video object are sequentially reproduced. ,Raw The video object information generated by the unit and a second recording step of recording on the optical disk.

According to this configuration, the reproducing apparatus can smoothly perform special reproduction such as reverse reproduction by referring to the system clock reference in the video object information before reproducing the video object.

[Brief description of the drawings]

FIG. 1 shows an appearance of an optical disk recording / reproducing apparatus.

FIG. 2 is a diagram showing a lead-in area, a data area, and a lead-out area provided in an area of an optical disc, and an outline of a file configuration recorded in the data area.

FIG. 3 is a diagram showing VR_MOVIE. FIG. 4 is a diagram illustrating a data configuration of a VRO file.

FIG. 4 is a management information file VR_MANG shown in FIG. 2;
R. FIG. 3 is a diagram hierarchically showing a data structure of an IFO.

FIG. 5 is a block diagram showing a configuration of a main part of the optical disc recording / reproducing apparatus shown in FIG.

FIG. 6 is a block diagram showing a detailed configuration of an encoder unit 104 in FIG.

FIG. 7 is a flowchart illustrating details of a pause process performed by an encoder control unit 1507;

FIG. 8 is a flowchart illustrating details of a pause release process performed by an encoder control unit 1507.

FIG. 9 shows an internal operation of the encoder unit 104 before and after a pause.

FIG. 10 is a block diagram showing a detailed configuration of a decoder unit 106 in FIG.

[Explanation of symbols]

 Reference Signs List 1 optical disk recording / reproducing device 2 television receiver 101 user interface unit 102 system control unit 103 input unit 104 encoder unit 105 output unit 106 decoder unit 107 track buffer 108 drive 1405 output unit 1407 track buffer 1501 video encoder 1502 buffer 1502 video encode buffer 1503 audio encoder 1504 audio encode buffer 1505 control information buffer 1506 STC unit 1507 encoder control unit 1508 system encoder 1601 virtual playback time clock unit 1602 video packing unit 1603 virtual decoder buffer 1604 audio packing unit 1605 virtual decoder buffer 1607 interleave unit 1702 Demultip Lexer 1703 Video buffer 1704 Video decoder 1705 Reorder buffer 1706 Switch 1707 Audio buffer 1708 Audio decoder 1709 Control information output unit

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/92 H04N 5/93 Z 5/93 G11B 27/02 K (72) Inventor Kazuhiko Nakamura Kadoma, Osaka 1006 Kadoma, Matsushita Electric Industrial Co., Ltd. (72) Inventor Tomoyuki Okada 1006 Kadoma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (22)

[Claims] 1. A receiving means for receiving a user operation including a recording start instruction, a recording end instruction, a pause instruction, and a pause release instruction, and a period from a recording start instruction or a pause release instruction until a pause instruction or a recording end instruction is received. Encoding means for generating one video object by compressing and encoding audio-visual data, and generating a video object which can be seamlessly reproduced with the video object generated immediately before when a pause release instruction is received; Each time a video object is generated, generating means for generating a seamless flag indicating whether seamless reproduction is possible when the video object and the immediately preceding video object are sequentially reproduced; and a video generated by the encoding means. Object and the sheet generated by the generator An optical disk recording apparatus, comprising: recording means for recording a flag on an optical disk. 2. The optical disc recording apparatus according to claim 1, wherein the seamlessly playable video object does not cause overflow and underflow in a video buffer in a playback apparatus that temporarily stores compressed video data. An optical disc recording apparatus, characterized in that compressed video data included in the seamlessly playable video object is input to a video buffer in a playback device following the immediately preceding video object. 3. The optical disc recording apparatus according to claim 2, wherein when the seamless flag indicates that seamless reproduction is possible, the decoder in the reproduction apparatus resets the internal state of the decoder after the reproduction of the immediately preceding video object is completed. An optical disk recording apparatus, which starts reproduction of the video object without the need. 4. The optical disc recording apparatus according to claim 1, wherein said encoding means completes generation of a video object when a pause instruction is received, and saves an internal state of said encoding means at the time of completion. An optical disc recording apparatus, wherein when a pause release instruction is received, generation of a new video object is started with the stored internal state as an initial state. 5. The optical disc recording apparatus according to claim 4, wherein the generating unit generates a seamless flag indicating that seamless reproduction is possible when the encoding unit completes generation of the video object by a pause instruction. An optical disc recording apparatus characterized in that when an encoding means completes generation of a video object in response to an end instruction, a seamless flag indicating no seamless reproduction is generated. 6. The optical disk recording apparatus according to claim 5, wherein the generation unit generates the last system clock reference value of the video object whose generation has been completed by the pause instruction, and the video whose generation has been started by the pause release instruction. The first system clock reference value of the object is obtained from encoding means, and the recording means uses the last system clock reference value, the first system clock reference value, and the seamless flag as video object information as an optical disc. An optical disk recording device for recording information on an optical disk. 7. The optical disk recording apparatus according to claim 4, wherein, when a pause instruction is received, said encoding means reproduces compressed audio data in an audio buffer remaining without being multiplexed in the video object. An optical disk recording device, wherein the virtual buffer size obtained by simulating the data size of a compressed video data input buffer in the device and the virtual buffer size are stored as the internal state. 8. The optical disk recording apparatus according to claim 6, wherein the encoding means performs a period immediately before or immediately after the division on the audio data divided by the pause instruction and the pause release from the audio frame. An optical disk recording apparatus characterized in that compressed audio data is generated after replacing a short period with silent data. 9. The optical disc recording apparatus according to claim 4, wherein said encoding means temporarily compresses and encodes the video data by the first encoder, and temporarily compresses and compresses the video data by the first encoder. A second buffer for sequentially compressing and encoding the audio data, a second buffer for temporarily storing the compressed audio data compressed and encoded by the second encoder, and a compression from the first buffer. A video object is generated by multiplexing the video data and the compressed audio data from the second buffer in a fixed-length pack unit. Multiplexing means for assigning a pack unit, and compressed video data First virtual buffer means for simulating the data occupancy of the temporarily held video buffer; and simulating the data occupancy of the audio buffer for temporarily holding the compressed audio data in the playback device according to the time information in pack units. When the pause instruction is received, the first encoder and the second encoder are stopped, and the states of the first, second buffers, the first and second virtual buffers are saved, and the pause is performed. An encoding control unit configured to generate a seamlessly playable video object by restarting the first encoder and the second encoder with the saved state as an initial state when a release instruction is received. Optical disk recording device. 10. The optical disc recording apparatus according to claim 9, wherein the second encoding unit outputs audio data divided by a pause instruction and a pause release during a period immediately before or immediately after the division. An optical disc recording apparatus, wherein compressed audio data is generated after replacing silent data for a period shorter than a frame. 11. The optical disk recording apparatus according to claim 10, wherein said second encoding means has a mute circuit capable of replacing input audio data with silence data, and is divided by a pause instruction and a pause release. An optical disk recording apparatus characterized in that a mute circuit is operated in a period immediately before or immediately after the division of audio data and shorter than an audio frame. 12. A reproducing apparatus for reproducing a video object recorded on an optical disc, wherein the optical disc records a plurality of video objects and a plurality of pieces of video object information, wherein the video objects are compressed video data and compressed audio data. Data, the video object information corresponds to the video object, includes a seamless flag, the seamless flag indicates whether seamless playback is possible if the corresponding video object and the preceding video object are played sequentially, The optical disc reproducing apparatus includes: a reading unit that reads video object information and a video object corresponding to the video object information from the optical disc; and decodes the video object read by the reading unit to obtain audio / video data. A decoding means for generating an optical disk reproducing apparatus, characterized in that it comprises a control means for controlling the seamless reproduction by the decoding means based on the seamless flag of the read video object information by reading means. 13. The optical disk reproducing apparatus according to claim 12, wherein the decoding unit separates the video object read by the reading unit into compressed video data and compressed audio data. A video buffer for temporarily storing compressed video data; an audio buffer for temporarily storing separated compressed audio data; a first decoder for decoding compressed video data in the video buffer; And a second decoder for decoding. When the seamless flag corresponding to the video object to be reproduced next indicates that seamless reproduction is possible, the control means controls a video buffer and a video buffer when switching from the current video object to the next video object. Without initializing the audio buffer, An optical disc reproducing apparatus for controlling a next video object read by a reading means to be supplied to a decoding means. 14. The optical disc reproducing apparatus according to claim 13, wherein the video object information includes a seamless flag,
Including a last system clock reference value of a preceding video object and a first system clock reference value of a corresponding video object, wherein the control means, when a seamless flag indicates seamless playback possible, a last system clock reference value; An optical disc reproducing apparatus for controlling switching of a system time clock inside decoding means according to a first system clock reference value of a corresponding video object. 15. An optical disk recording method, comprising: a receiving step of receiving a user operation including a recording start instruction, a recording end instruction, a pause instruction, and a pause release instruction; and a pause instruction or a recording end instruction from a recording start instruction or a pause release instruction. During the period until the instruction is received, one video object is generated by compressing and encoding the audiovisual data, and when the pause release instruction is received, seamless reproduction with the video object generated immediately before is possible. An encoding step of generating a video object; a first recording step of recording the video object generated by the encoding means on an optical disc; and each time a video object is generated, the video object and the immediately preceding video object are sequentially reproduced. Can be played seamlessly when An optical disc recording method, comprising: a generating step of generating video object information including a seamless flag indicating whether or not the video object information has been generated; and a second recording step of recording the video object information generated by the generating means on an optical disc. 16. The optical disc recording method according to claim 15, wherein the seamlessly reproducible video object does not cause an overflow and an underflow in a video buffer in a reproducing apparatus for temporarily storing compressed video data. An optical disc recording method, wherein compressed video data included in a video object that can be seamlessly reproduced is input to a video buffer in a reproducing apparatus, following a video object immediately before. 17. The optical disc recording method according to claim 16, wherein when the seamless flag indicates that seamless reproduction is possible, the decoder in the reproduction device resets the internal state of the decoder after the reproduction of the immediately preceding video object is completed. An optical disc recording method, characterized in that reproduction of the video object is started without the need. 18. The optical disc recording method according to claim 17, wherein the encoding step completes generation of the video object when a pause instruction is received, and saves an internal state of the encoder at the time of completion. An optical disc recording method, wherein when a pause release instruction is received, generation of a new video object is started with the stored internal state as an initial state. 19. The optical disc recording method according to claim 18, wherein the generation step generates a seamless flag indicating that seamless reproduction is possible when the generation of the video object is completed by a pause instruction in the encoding step. An optical disk recording method, wherein, when the generation of a video object is completed by an end instruction in the encoding step, a seamless flag not indicating that seamless reproduction is possible is generated. 20. The optical disc recording method according to claim 19, wherein, in the generating step, a video system whose generation is started by a pause release instruction and a last system clock reference value of a video object whose generation is completed by a pause instruction. Obtaining the first system clock reference value of the object from the encoder; and the second recording step includes, as the video object information, the optical disc using the last system clock reference value, the first system clock reference value, and the seamless flag. An optical disk recording method characterized by recording information on an optical disk. 21. The optical disk recording method according to claim 18, wherein, when a pause instruction is received, the compressed audio data in an audio buffer remaining without being multiplexed in the video object when the pause instruction is received is reproduced. The virtual buffer size obtained by simulating the data size of the compressed video data input buffer in the device is stored as the internal state. An optical disc recording method characterized by the above-mentioned. 22. The optical disk recording method according to claim 18, wherein the encoding step is a period immediately before or immediately after the division of the audio data divided by the pause instruction and the pause release, and An optical disk recording method, wherein compressed audio data is generated after replacing a short period with silent data.