JP4089017B2 - After-recording method and apparatus for digital recording medium and reproducing method and apparatus for digital recording medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for performing after recording on video data or the like recorded on a digital recording medium.
[0002]
[Prior art]
After-recording (hereinafter, also simply referred to as “after-recording”), for example, after recording original data (video data only, or audio data such as video data and lines) in studio recording or outdoor recording, Is a voice editing processing method in which new voice data (after-recording voice data) is added and recorded, or a part of the original voice data is replaced with such after-recording voice data.
[0003]
There are several methods for performing post-recording on original data recorded on a digital recording medium, for example, the following (1) to (3). The description will be made on the methods (1) and (3).
[0004]
(1) After-recording sound is input while reproducing the original data, and this after-recording sound data is multiplexed with the original data in real time when the original data is reproduced and recorded on the digital recording medium.
[0005]
(2) Recording the after-recording sound data input while reproducing the original data once on another recording medium (that is, not in real time), and then recording the after-recording sound data reproduced from the other recording medium with the original data. Multiplex and record on a digital recording medium.
[0006]
(3) After-recording audio data is recorded on the digital recording medium without being multiplexed with the original data, and the original audio data read from the digital recording medium and the after-recording audio data are mixed during reproduction. Output as sound.
[0007]
FIG. 5 shows an example of recording data (bit stream) on a digital recording medium. A video bit stream V, a main audio bit stream A1, and a sub audio bit stream A2 are multiplexed and recorded in one stream. Since the bit rate of the audio bit stream is lower than the bit rate of the video bit stream (for example, the former is about 6 Mbps or 8 Mbps, while the latter is about 256 kbps, the ratio is about 25 to 1 or 32 to 1. However, while V occupies most of the recording area, the recording areas A1 and A2 are periodically scattered.
[0008]
For example, MPEG2 is used as an encoding standard for a digital recording medium. In this case, a video bitstream V compressed and encoded with MPEG2 video and a main audio bitstream compressed and encoded with MPEG2 audio are used. A1 and the sub audio bitstream A2 are recorded by the MPEG2 system in a packet multiplexing manner.
[0009]
FIG. 6 shows an example of a processing process when post-recording is performed on the original data recorded on the digital recording medium as in the example of FIG. 5 by the method (1). First, the video bit stream V and the main audio bit stream A1, which are original data, are read from the digital recording medium, demodulated and error-corrected by the RF and demodulation circuit 21 and the ECC circuit 22, and then read rate and decoding processing are performed. The signal is decoded by a decoder (including a demultiplexing unit for demultiplexing, a video decoder, and an audio decoder) 24 through a buffer 23 for absorbing the difference from the rate, and from the video output terminal P1 and the audio output terminal P2. Original video and audio are played by sending to a display and speakers (not shown).
[0010]
The user who wants to perform dubbing, while reproducing video and audio in this way, dubbed audio data (for example, audio data generated in front of a microphone (not shown) or audio selected and reproduced from a dubbing audio library tape). Data) is input from the audio input terminal P3. As the after-recording audio data to be actually recorded, the input after-recording audio data is often mixed with the original (main audio) audio data by the mixer 25.
[0011]
The post-record audio data is encoded by the encoder 26 in synchronization with the reproduction of the original video and audio, and after passing through a buffer 27 for absorbing the difference between the encoding processing rate and the write rate, the ECC circuit 28, the modulation and RF circuit After the error correction code is added and modulated in 29, the post-recording audio data is written in the recording area of the sub audio bitstream A2.
[0012]
Here, the recording area of the sub audio bit stream A2 only needs to have a capacity capable of recording after-recording audio data, so it is not necessary to record the audio data before performing after-recording, and is blank. May be. However, when the after-recording audio data is written in the blank recording area of the sub audio bit stream A2, the video bit stream V, the main audio bit stream A1, and the sub audio bit stream A2 are correct (the MPEG2 system standard). If the bit stream does not become a multiplexed bit stream, it is necessary to perform multiplexing again after dubbing.
[0013]
The dubbing is now complete. When the video and audio as a completed work are reproduced from the digital recording medium after the post-recording as described above, any of the original audio (main audio bitstream A1) and after-recording audio (sub audio bitstream A2) is selected. Can be selected and played.
[0014]
In the above processing example, it is assumed that only after-recording audio data is written at the time of writing for convenience. However, in practice, it is necessary to rewrite the original data together with the writing of the post-recording audio data because the ECC circuit performs processing in units of data blocks of a certain size. That is, for example, if the size of the packet of the audio bit stream is 2 kbytes, but the size of the data block of the ECC circuit is 32 kbytes or 64 kbytes, the error correction code is added by the ECC circuit 28. In addition, the recording must be performed in units of 32 or 64 kbytes of data including the after-recording audio data and the video bitstream V recorded in the area adjacent to the recording area of the sub-audio bitstream A2 to which the audio data is to be written. I must. As described above, when new data is written in a part of the area of the digital recording medium, the data in the area adjacent thereto is also a target to which the error correction code should be re-added, so that it is necessary to rewrite the original data. .
[0015]
[Problems to be solved by the invention]
By the way, in an after-recording process that has undergone such a processing process, it takes approximately the following processing time in each circuit until the after-recording audio data is written after the video bit stream V and the main audio bit stream A1 are read.
[0016]
ECC circuits 22 and 28: about several tens of milliseconds each
Buffers 23 and 27: about several hundred milliseconds to several tens of seconds (there are large variations depending on the function of the buffer used)
Decoder 24: about several tens of milliseconds
Encoder 26: about several tens of milliseconds
[0017]
Accordingly, since it takes a processing time of about several hundred milliseconds to several seconds (in some cases, about several tens of seconds), this processing time is longer than the area where the post-recording audio data is recorded with the original data to be reproduced at the same time. There has been a problem of delay that data is written in an area corresponding to a reproduction time delayed by a minute. That is, for example, in the case of packet multiplexing, post-recording audio data is recorded as a packet having a time stamp indicating a time later than the time indicated by the time stamp in the packet of the original data to be reproduced at the same time.
[0018]
In addition, since the length of this processing time usually varies somewhat every time after-recording is performed, the temporal relationship of the recording area of the after-recording audio data with respect to the recording area of the original data also varies every time after-recording is performed. As a result, conventionally, when reproducing video and audio as a finished product, it has been difficult to reproduce after-recording audio with the original video or the like accurately in time.
[0019]
The present invention has been made in view of the above points. Even after the processing process shown in FIG. 6 adopting the after-recording method of (1) above, the after-recording sound can be easily and accurately timed with the original video. It is an object of the present invention to provide an after-recording method and apparatus that can be reproduced in a consistent manner.
[0020]
Further, it is intended to provide an after-recording method and apparatus, and a reproducing method and apparatus, which can reproduce after-recording audio with the original video or the like accurately in time even if the after-recording method of (3) is adopted. It is what.
[0021]
[Means for Solving the Problems]
The after-recording method according to the present invention is as described in claim 1, It has recording areas for video bitstream, main audio bitstream, and sub audio bitstream From recording media , Including a video bitstream and at least one audio bitstream In synchronization with the first step of reading the bit stream, the second step of decoding the bit stream, and decoding of the bit stream, a new step is performed. voice A third step of encoding the data into a bit stream for post-recording, and the bit stream for post-recording Sub audio bitstream recording area As the information indicating the temporal correspondence between the fourth step written to the recording medium and the bit stream read from the recording medium and the bit stream for post-recording, the information corresponds to the bit stream for post-recording among the bit streams read from the recording medium. And a fifth step of writing information indicating the presentation time stamp of the starting portion in an area for recording additional information of the recording medium.
[0022]
According to this post-recording method, It has recording areas for video bitstream, main audio bitstream, and sub audio bitstream Read from the recording medium Including a video bitstream and at least one audio bitstream Synchronized with the decoding of the bitstream voice The bit stream for post-recording obtained by encoding the data is recorded on the recording medium. Sub audio bitstream recording area To write to.
[0023]
In this way, for post-recording voice Data Sub audio bitstream recording area By writing to the original data (Video bitstream and at least one audio bitstream) The temporal relationship of the recording area of the after-recording data with respect to the recording area is clarified. As a result, when the video and audio as a completed work are reproduced, it is possible to reproduce the after-recording data easily and accurately in time with the original data. Then, as information indicating the temporal correspondence between the original data and the after-recording data, information indicating the presentation time stamp of the portion of the original data that starts to correspond to the after-recording data is written in the recording area of the additional information on the recording medium. Even if the original data and the after-recording data are recorded without being multiplexed, it is possible to reproduce the after-recording data accurately in time with the original data based on this information in the additional information.
[0024]
An after-recording apparatus according to the present invention is also claimed in the claims. 5 As described in It has recording areas for video bitstream, main audio bitstream, and sub audio bitstream From recording media , Including a video bitstream and at least one audio bitstream Read means for reading the bit stream, a decoder for decoding the bit stream, and a new voice The encoder encodes the data into a bit stream for after recording, the writing means for writing the bit stream for after recording to the recording medium, and the encoder encodes in synchronization with the decoding of the bit stream by this decoder. The after-recording bit stream is controlled by this writing means. Sub audio bitstream recording area As the information indicating the temporal correspondence between the control means to be written to the recording medium and the bit stream read from the recording medium and the bit stream for after recording, it corresponds to the bit stream for after recording in the bit stream read from the recording medium. And additional information writing means for writing information indicating the presentation time stamp of the part to be started into an area for recording additional information on the recording medium.
[0025]
According to this after-recording apparatus, the data is read from the recording medium by the reading means. Including a video bitstream and at least one audio bitstream In synchronization with decoding by the bitstream decoder, a new voice When the data is encoded by the encoder to obtain the after-recording bit stream, the after-recording bit stream is recorded on the recording medium by the writing unit under the control of the control unit. Sub audio bitstream recording area Is written to.
[0026]
In this way, for post-recording voice Data Sub audio bitstream recording area As a result, the temporal relationship between the recording area of the after-recording data and the recording area of the original data becomes clear. As a result, when the video and audio as a completed work are reproduced, it is possible to reproduce the after-recording data easily and accurately in time with the original data. Then, as information indicating the temporal correspondence between the original data and the after-recording data, information indicating the presentation time stamp of the portion of the original data that starts to correspond to the after-recording data is written in the recording area of the additional information on the recording medium. Even if the original data and the after-recording data are recorded without being multiplexed, it is possible to reproduce the after-recording data accurately in time with the original data based on this information in the additional information.
[0027]
Claims 8 And 1 1 The reproduction method and apparatus described in (1) is an example of a method and apparatus suitable when the after-recording method (3) described above is employed.
[0029]
According to this reproduction method and apparatus, It has recording areas for video bitstream, main audio bitstream, and sub audio bitstream Original data from the additional information recording area of the recording medium (Video bitstream and at least one audio bitstream) And dubbing voice As the information indicating the temporal correspondence with the data, voice Information indicating the presentation time stamp of the part that starts to correspond to the data is read, and based on this information, the original data and Written in the recording area of the sub-audio bitstream of the recording medium Dubbing voice Since the data is read and decoded synchronously, the original data and the after-recording voice Even if data is recorded without being multiplexed, voice The data is played back with the original data accurately matched in time.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
First, when the method (1) of the above-described after-recording methods (1) to (3) is adopted (that is, after-recording sound is input while reproducing the original data, the after-recording sound data is reproduced as the original data. An example of the present invention will be described in the case where the original data is sometimes multiplexed in real time and recorded on the digital recording medium.
[0031]
In the case of adopting the after-recording method of (1), what kind of area is specifically determined as the “predetermined area” of the digital recording medium for recording the after-recording audio data is, for example, the following (A) or A region like (B) is conceivable. However, these are preferable examples, and are not intended to exclude other areas.
[0032]
(A) Area corresponding to the reproduction time substantially equal to the recording area of the original data
This is an example determined in accordance with a system restriction in a multiplexing system such as an MPEG system. This area will be described in relation to FIG. 5 and FIG. 6. This area is a recording area of the sub audio bit stream A2 that is reproduced substantially simultaneously with the main audio bit stream A1 read out in the process of FIG. For example, it can be considered as any one of the following (i) to (ii).
[0033]
(I) Recording area of the sub audio bit stream A2 that is spatially closest to the recording area of the main audio bit stream A1
(Ii) The sub audio bit stream A2 to which time information indicating substantially the same time as the time information added to the main audio bit stream A1 (presentation time stamp (PTS) in a packet in the MPEG system) is added. Recording area
[0034]
(B) Area corresponding to time greatly delayed from original data recording area
This is an example determined without complying with the restrictions on the method in the multiplexing method.
[0035]
Of these, when data for after-recording is written in the area (A), a data channel for reading original data from the digital recording medium and a data channel for writing data for after-recording to the digital recording medium are separately provided. Is necessary. Therefore, either a method of providing two heads for reading and writing and performing reading and writing independently, or a method of seeking and reading and writing in a time-division manner by seeking one head. (The latter method is, of course, limited to the case where post-recording is performed on original data recorded on a random-access recording medium such as a disk).
[0036]
Such a method is generally the same as the method when data input / output is performed in a multi-channel in a recording / reproducing apparatus. However, even if the number of channels is only two and reading and writing are performed independently, only two systems are necessary, and even when reading and writing are performed in a time-sharing manner, the distance according to the size of the delay Since the seek distance is relatively small since the head only needs to be sought (no full-stroke seek is performed), it can be said that the conditions for realization are not stricter than in general multi-channel.
[0037]
On the other hand, in the case of writing after-recording data in the area (B), it is sufficient to read the original data with one head and then write the after-recording data at the current position of the head. . Therefore, it can be said that this is easier to implement in terms of reducing the number of head systems and simplifying control of the head.
[0038]
However, in this case, at the time of reproduction of video and audio as a finished product, it is necessary to perform a process for reproducing after-recording data in time coincidence with the original data. This process is particularly troublesome during special playback such as slow playback or double speed playback. Moreover, performing such a process leads to an increase in the cost of the apparatus. Therefore, from these points, it can be said that it is preferable to write in the area (A).
Therefore, in the following, a specific example will be described taking the case of writing in the area (A) as an example.
[0039]
FIG. 1 shows an example of a system configuration of an optical disc apparatus to which the after-recording method and apparatus of the present invention are applied when the above-described after-recording method (1) is adopted.
In this optical disc apparatus, one optical pickup (optical head) 2 is provided for one rewritable optical disc 1, and the optical pickup 2 is shared for both reading and writing of data. In the same manner as shown in FIG. 5, the video bit stream V, the main audio bit stream A1, and the auxiliary audio bit stream A2 are recorded on the optical disc 1 by the MPEG2 system in a packet multiplexing system. In each of the bitstreams V, A1, and A2, there are packets having a presentation time stamp at a rate of one for several packets.
[0040]
The bit stream read from the optical disc 1 by the optical pickup 2 is an RF and demodulation / modulation circuit 3 (having the functions of the RF and demodulation circuit 21 and the modulation and RF circuit 29 in FIG. 6), and an ECC circuit 4 ( 6 having both the functions of the ECC circuit 22 and the ECC circuit 28 in FIG. 6), the data is demodulated and error-corrected, and then read through the switch 5 to absorb the difference between the read rate and the decode processing rate. It is sent to the channel buffer 6.
[0041]
The bit stream taken out from the read channel buffer 6 is decoded by a decoder (including a demultiplexing unit, a video decoder, and an audio decoder) 7, and is sent from a video output terminal P1 and an audio output terminal P2 to a display and a speaker (not shown). While being sent and reproduced, it is sent to the bypass buffer 8. The bypass buffer 8 plays a role of accumulating the bit stream read from the optical disc 1 even after the decoding process and rewriting it on the optical disc 1.
[0042]
The bit stream extracted from the bypass buffer 8 passes through a detector 9 that detects the media type (video, main audio, or sub audio) of the packet based on the stream ID in each packet, and the switch 10 Sent to one fixed contact.
[0043]
On the other hand, the audio data input from the audio input terminal P3 is encoded by the encoder 11 and then stored in the encoder buffer 12. The audio data extracted from the encoder buffer 12 is sent to the other fixed contact of the switch 10.
[0044]
The movable contact of the switch 10 is connected to a write channel buffer 13 for absorbing the difference between the encoding processing rate and the write rate. Data sent to the write channel buffer 13 via the switch 10 (the bit stream extracted from the bypass buffer 8 or the audio data extracted from the encoder buffer 12) is extracted from the write channel buffer 13 and the switch 5 Then, the error correction code is added and modulated by the ECC circuit 4, the RF and the demodulation / modulation circuit 3, and then written onto the optical disk 1 by the optical pickup 2.
[0045]
As an example, the read rate and the write rate are equal to each other (or both the read rate and the write rate are variable and their maximum rates are equal to each other).
[0046]
Also in this optical disk apparatus, since the bit stream is read from the optical disk 1 in this way and the audio data input in synchronization with the reproduction is written to the optical disk 1, it is still a number for the reason described with reference to FIG. Processing time from 100 milliseconds to several seconds is required.
[0047]
Therefore, the position of the optical pickup 2 with respect to the optical disc 1 is advanced by this processing time between this reading and writing. In other words, considering a certain time as a reference, the position W at which the optical pickup 2 must exist in order to write data in the area corresponding to the reproduction time substantially equal to the recording area of the read data is shown in FIG. As shown in FIG. 4, the time is behind the reading position R of the optical pickup 2 at this time by this processing time.
[0048]
Returning to FIG. 1, the system controller 14 controls the operation of each part of the optical disk apparatus during post-recording as will be described later. Although not shown, the ROM stores a CPU and a processing program to be executed by the CPU. And a RAM for temporarily storing data and the like generated during the processing. In this control, the fine adjustment of the position of the optical pickup 2 is performed by detecting the address detection circuit 15 that takes in the bit stream demodulated by the RF and demodulation / modulation circuit 3 and detects the address information of the data currently being read. Based on the results. The switching control of the switch 10 is performed based on the detection result of the detector 9.
[0049]
Next, an example of processing executed by the system controller 14 during post-recording will be described.
[First step]
First, the user designates original data to be post-recorded by operating an operation panel (not shown), or records on the optical disc 1 based on reading designation information of the original data to be post-recorded previously written on the optical disc 1. The range of the original data to be dubbed is determined among the original data being recorded.
[0050]
Subsequently, based on the address information of the original data to be dubbed, the optical pickup 2 is caused to seek to the read start position X0. Then, the optical pickup 2, RF, demodulation / modulation circuit 3, and ECC circuit 4 are set to the reading mode, the switch 5 is switched to the reading channel buffer 6 side, and the position of the optical pickup 2 is finely adjusted. Start reading by. As a result, the original data to be dubbed is accumulated in the read channel buffer 6.
[0051]
FIG. 3 shows the relationship between the position of the optical pickup 2 and the read / write state at each time during post-recording (A in FIG. 3), and data accumulation in the read channel buffer 6 and the write channel buffer 13 at these times. The quantity (B and C in the figure) is shown. In FIG. 3A, a thick solid line indicates that reading is in progress, a broken line indicates that writing is in progress, and a thin solid line indicates that seeking is in progress.
[0052]
In FIG. 3, the accumulation processing in the read channel buffer 6 corresponds to the stage from the time T0 to T2, and the state in which the data accumulation amount of the read channel buffer 6 increases is also shown in FIG. .
[0053]
[Second step]
Original data is taken out from the read channel buffer 6 and is decoded and reproduced by the decoder 7 while being stored in the bypass buffer 8.
[0054]
The decoding process in the decoder 7 is continuously performed until the dubbing is completed regardless of the position of the optical pickup 2 and whether the reading mode or the writing mode is set.
This decoding process is started between time T0 and time T1 in relation to FIG.
[0055]
[Third step]
The post-record audio data input by the user in synchronization with the reproduction of the original data is encoded by the encoder 11 and stored in the encoder buffer 12.
The encoding process in the encoder 11 is continuously performed until the dubbing is completed regardless of the position of the optical pickup 2 and whether the reading mode or the writing mode is set.
[0056]
[Fourth step]
Original data is extracted from the bypass buffer 8 and sent to the detector 9.
When the detection result of the detector 9 indicates that the original data currently extracted from the bypass buffer 8 is the video bit stream V or the main audio bit stream A1, the movable contact of the switch 10 is connected to the detector 9 side. Switching to the fixed contact, the original data is stored in the write channel buffer 13.
[0057]
On the other hand, when the detection result of the detector 9 indicates that the original data currently extracted from the bypass buffer 8 is the sub audio bit stream A2, the movable contact of the switch 10 is changed to a fixed contact on the encoder buffer 12 side. After switching, the post-recording audio data extracted from the encoder buffer 12 is accumulated in the write channel buffer 13. At the same time, the sub audio bit stream A2 is taken out from the bypass buffer 8 and continuously supplied to the fixed contact on the detector 9 side, so that the sub audio bit stream A2 is ignored on the write channel buffer 13 side.
[0058]
As a result, the bit that combines the original data and the after-recording audio data by replacing the sub-audio bit stream A2 of the video bit stream V, the main audio bit stream A1, and the sub-audio bit stream A2 that is the original data with the after-recording audio data. Streams are accumulated in the write channel buffer 13.
[0059]
The accumulation processing in the write channel buffer 13 is continued until after the dubbing is completed regardless of the position of the optical pickup 2 and whether it is in the read mode or the write mode.
The accumulation processing in the write channel buffer 13 corresponds to the stage after time T1 in FIG.
[0060]
Subsequently, when a certain condition determined by any one or a combination of two or more of the following factors (a) to (f) is satisfied, reading of the original data is stopped, and the switch 5 Is switched to the write channel buffer 13 side.
(A) Elapsed time from start of reading
(B) Amount of data stored in the read channel buffer 6
(C) Amount of data stored in the write channel buffer 13
(D) Media rate (read / write rate for the optical disc 1)
(E) Data rate of read channel and write channel (consumption rate of decoder 7, output rate of encoder 11)
(F) Capacity of buffers 6 and 13
[0061]
Finally, the address information of the original data sent to the read channel buffer 6 is stored. (When the next reading is resumed, the original data following the data sent to the buffer 6 at the end is read from the optical disc 1 based on this address information.)
The switching of the switch 5 corresponds to the stage at time T2 in FIG.
[0062]
Subsequently, based on information stored in advance in the system controller 14, the optical pickup 2 is sought from the current position X2 to the writing start position (here, the same position X0 as the reading start position), and approaches the position X0. And finely adjust the position of the optical pickup 2.
[0063]
This seek operation corresponds to the stage from time T2 to T3 in FIG. Taking FIG. 2 as an example, the position of the optical pickup 2 changes from R to W by this seek operation.
[0064]
Then, the optical pickup 2, the RF, the demodulation / modulation circuit 3, and the ECC circuit 4 are switched to the write mode, and data is taken out from the write channel buffer 13. As a result, data obtained by replacing the sub audio bit stream A2 with the post-record audio data in the original data read from the optical disk 1 is substantially equal to the original recording area on the optical disk 1 after the error correction code is added again. Will continue to be written. In other words, the post-recording audio data to be reproduced simultaneously with the original data in the area of the auxiliary audio bitstream A2 corresponding to the reproduction time substantially equal to the recording area of the video bitstream V and the main audio bitstream A1 as the original data. Are multiplexed and recorded.
[0065]
This writing process corresponds to the stage from time T3 to T4 in FIG. 3, and the state in which the amount of data stored in the write channel buffer 13 decreases is also shown in FIG.
[0066]
Subsequently, when a certain condition determined by any one or a combination of two or more of the elapsed time from the start of writing and the above factors (b) to (f) is satisfied, Data writing is stopped, and the switch 5 is switched again to the read channel buffer 6 side. Then, the address information of the last written data is stored. (When the next writing is resumed, the data following the last written data is taken out from the write channel buffer 13 based on this address information.)
The switching of the switch 5 corresponds to the stage at time T4 in FIG.
Up to the fourth step, one cycle of the after-recording operation is completed.
[0067]
Subsequently, based on the address information stored when the previous switch 5 is switched to the write channel buffer 13 side, the optical pickup 2 is sought from the current position X1 to the position X2 where the previous reading was stopped.
[0068]
This seek operation corresponds to the stage from time T4 to T5 in FIG. Taking FIG. 2 as an example, the position of the optical pickup 2 changes from W to R by this seek operation. Thus, the position of the optical pickup 2 reciprocates between the reading position and the writing position.
[0069]
Then, the optical pickup 2, RF, demodulation / modulation circuit 3, and ECC circuit 4 are set to the read mode again, the position of the optical pickup 2 is finely adjusted, and then reading by the optical pickup 2 is resumed. Hereinafter, until all of the post-recording data corresponding to the original data to be post-recording is completed (or until the end of post-recording is instructed by operation of an operation panel (not shown)), it is shown as a stage after time T5 in FIG. In addition, reading and writing as described above are performed in a time-sharing manner.
[0070]
In the example of FIG. 1, the detector 9 is provided at the subsequent stage of the bypass buffer 8, but the detector 9 is provided at the previous stage of the bypass buffer 8, or the type of packet media is detected by the decoder 7. Also good. However, when doing so, the system controller 14 needs to store the relationship between the detection result and the accumulated data of the bypass buffer 8.
[0071]
In addition to detecting the type of media, a detector for detecting the reproduction time of each packet based on the presentation time stamp in the packet may be provided. By doing so, the process of multiplexing and recording the after-recording audio data in the area corresponding to the reproduction time substantially equal to the recording area of the video bit stream V and the main audio bit stream A1 can be performed with higher accuracy.
[0072]
Further, instead of the combination of the detector and the switch 10, a multiplexer for multiplexing the original data extracted from the bypass buffer 8 and the post-recording audio data extracted from the encoder buffer 12 may be provided. . By doing so, multiplexing can be performed more efficiently and with high accuracy, and multiplexing can be performed with a configuration different from the original data.
[0073]
FIG. 4 shows another example of the system configuration of the optical disc apparatus to which the after-recording method and apparatus of the present invention is applied when the above-described after-recording method (1) is adopted. The same reference numerals are given and redundant description is omitted.
[0074]
In this optical disc apparatus, two systems of work memories 16 and 17 are provided as work memories for the ECC circuit 4, and data supplied to the ECC circuit 4 is transferred from the work memories 16 and 17 via the switch 18. (In contrast, in the optical disc apparatus of FIG. 1, the ECC circuit 4 is provided with only one system work memory, not shown).
[0075]
The processing executed by the system controller 14 in this optical disc apparatus during post-recording has the following differences from the processing in the optical disc device of FIG. 1, but the other points are the same as those of the optical disc device of FIG. Is consistent with the process.
[0076]
[Differences in read mode]
Original data read from the optical disc 1 and supplied to the ECC circuit 4 is temporarily stored in, for example, one work memory 16 via the switch 18.
[0077]
When a certain condition determined by any one or a combination of two or more of the above factors (a) to (f) is satisfied and the switch 5 is switched to the write channel buffer 13 side, the switch 18 Is switched to the work memory 17 side.
[0078]
When reading the original data and storing the address information, the address information of the original data sent last is stored in the work memory 16 instead of the original data sent last to the read channel buffer 6.
[0079]
[Differences in write mode]
When a certain condition determined by any one or a combination of two or more of the above factors (a) to (f) is satisfied and the switch 5 is switched to the read channel buffer 6 side, the switch 18 Is switched to the work memory 16 side again.
[0080]
The advantages of performing such processing are as follows.
In the processing in the optical disk apparatus of FIG. 1, since the ECC circuit 4 performs processing in units of data blocks having a certain size, data that has been input to the ECC circuit 4 but has not reached the size of the data block. Is forced to be discarded in the ECC circuit 4 when the switch 5 is switched. Therefore, when the reading is resumed, the discarded data must be read again from the optical disc 1, and when the writing is resumed, the discarded data must be retrieved from the write channel buffer 13, which is inefficient.
[0081]
On the other hand, in the processing in the optical disk apparatus of FIG. 4, data that has been input to the ECC circuit 4 at the time of reading and writing but has not reached the size of the data block remains unchanged after the switch 5 is switched. 17, it is sufficient to read data following the data held in the work memory 16 from the optical disk 1 when reading is resumed, and the data following the data held in the work memory 17 is resumed when writing is resumed. Since it is sufficient to take it out, it is possible to perform post-recording efficiently.
[0082]
Next, when the method (3) of the above-mentioned after-recording methods (1) to (3) is adopted (that is, the after-recording audio data is multiplexed with the original data on the digital recording medium on which the original data is recorded). An example of the present invention will be described in the case where original audio data and post-recording audio data read out from the digital recording medium are mixed and output as a completed sound during recording and reproduction.
[0083]
FIG. 7 shows an example of the system configuration of an optical disc apparatus to which the after-recording method and apparatus of the present invention is applied when the after-recording method of (3) is adopted. The same reference numerals are used for the same parts as in FIG. A duplicate description will be omitted.
In this optical disk apparatus, one optical pickup (optical head) 2 is provided for one rewritable optical disk 19, and the optical pickup 2 is shared for both reading and writing of data. As shown in FIG. 8, a video bit stream V, a main audio bit stream A1, and a sub audio bit stream A2 are recorded on the optical disc 19. The video bit stream V and the main audio bit stream A1, which are original data, are recorded by the MPEG2 system in a packet multiplexing system (R portion). The sub audio bit stream A2 is included in the packet by the packet multiplexing method of the MPEG2 system, but is recorded independently of the bit streams V and A1 (W portion). In each of the bitstreams V, A1, and A2, there are packets having a presentation time stamp at a rate of one for several packets.
[0084]
The bit stream read from the optical disk 19 by the optical pickup 2 is an RF / demodulation / modulation circuit 3 (having both functions of the RF / demodulation circuit 21 and the modulation / RF circuit 29 in FIG. 6), an ECC circuit 4 ( 6 having both the functions of the ECC circuit 22 and the ECC circuit 28 in FIG. 6), the data is demodulated and error-corrected, and then read through the switch 5 to absorb the difference between the read rate and the decode processing rate. It is sent to the channel buffer 6.
[0085]
The bit stream taken out from the read channel buffer 6 is decoded by a decoder (including a demultiplexing unit, a video decoder, and an audio decoder) 7, and is sent from a video output terminal P1 and an audio output terminal P2 to a display and a speaker (not shown). Sent and played.
[0086]
On the other hand, the audio data input from the audio input terminal P3 is encoded by the encoder 11 and then stored in the encoder buffer 12. The audio data extracted from the encoder buffer 12 is sent to the write channel buffer 13 via the multiplexer 20.
[0087]
Data sent to the write channel buffer 13 (audio data extracted from the encoder buffer 12) is extracted from the write channel buffer 13, and an error occurs in the ECC circuit 4, RF, and demodulation / modulation circuit 3 via the switch 5. After the correction code is added and modulated, it is written onto the optical disk 19 by the optical pickup 2.
[0088]
In the case of this example, the read rate and the write rate are usually different from each other. In other words, the read rate is the bit rate of a stream in which video and audio are multiplexed, and the write rate is the bit rate of a stream consisting of a single audio, so the read rate is expected to be higher than the write rate. Is done.
[0089]
Also in this optical disk apparatus, since the bit stream is read from the optical disk 19 in this way and the audio data input in synchronization with the reproduction is written to the optical disk 19, it is still a number for the reason described with reference to FIG. Processing time from 100 milliseconds to several seconds is required.
[0090]
Accordingly, the position of the optical pickup 2 with respect to the optical disc 19 is advanced by this processing time between reading and writing. However, in this example, the bit stream of the original data is the R portion in FIG. 8, whereas the after-recording audio data is written in the W portion in FIG. 8 as will be described later, and both portions are different from each other. Since it is a bit stream, there is no need to consider delay. That is, a time difference corresponding to a delay due to signal processing occurs between the data being read and the data being written, but this does not affect the operation at the time of recording.
However, as will be described later, the temporal correspondence between the bit stream of the original data and the bit stream of the after-recording audio data is recorded in the TOC area of the optical disc 19.
[0091]
Returning to FIG. 7, the system controller 14 controls the operation of each part of the optical disk apparatus during post-recording as will be described later. Although not shown, the ROM stores a CPU and a processing program to be executed by the CPU. And a RAM for temporarily storing data and the like generated during the processing. In this control, the fine adjustment of the position of the optical pickup 2 is performed by detecting the address detection circuit 15 that takes in the bit stream demodulated by the RF and demodulation / modulation circuit 3 and detects the address information of the data currently being read. Based on the results.
[0092]
Next, an example of processing executed by the system controller 14 during post-recording will be described.
[First step]
First, the user designates original data to be post-recorded by operating an operation panel (not shown), or records on the optical disc 19 based on reading designation information of the original data to be post-recorded previously written on the optical disc 19. The range of the original data to be dubbed is determined among the original data being recorded.
[0093]
Subsequently, based on the address information of the original data to be dubbed, the optical pickup 2 is caused to seek to the read start position X0. Then, the optical pickup 2, RF, demodulation / modulation circuit 3, and ECC circuit 4 are set to the reading mode, the switch 5 is switched to the reading channel buffer 6 side, and the position of the optical pickup 2 is finely adjusted. Start reading by. As a result, the original data to be dubbed is accumulated in the read channel buffer 6.
[0094]
FIG. 9 shows the relationship between the position of the optical pickup 2 and the read / write status at each time during post-recording (FIG. A), and data accumulation in the read channel buffer 6 and the write channel buffer 13 at these times. The quantity (B and C in the figure) is shown. In FIG. 9A, a thick solid line indicates that reading is in progress, a broken line indicates that writing is being performed, and a thin solid line indicates that seeking is in progress.
[0095]
In FIG. 9, the accumulation processing in the read channel buffer 6 corresponds to the stage from time T0 to T2, and the state in which the data accumulation amount of the read channel buffer 6 increases is also shown in FIG. .
[0096]
[Second step]
Original data is taken out from the read channel buffer 6, decoded by the decoder 7 and reproduced.
[0097]
The decoding process in the decoder 7 is continuously performed until the dubbing is completed regardless of the position of the optical pickup 2 and whether the reading mode or the writing mode is set.
This decoding process is started between time T0 and time T1 in relation to FIG.
[0098]
[Third step]
The post-record audio data input by the user in synchronization with the reproduction of the original data is encoded by the encoder 11 and stored in the encoder buffer 12.
The encoding process in the encoder 11 is continuously performed until the dubbing is completed regardless of the position of the optical pickup 2 and whether the reading mode or the writing mode is set.
[0099]
[Fourth step]
The post-recording audio data taken out from the encoder buffer 12 is stored in a packet in accordance with the MPEG2 system standard by the multiplexer 20 and stored in the write channel buffer 13.
[0100]
As a result, a bit stream temporally corresponding to the original data is created and stored in the write channel buffer 13.
[0101]
The accumulation processing in the write channel buffer 13 is continued until after the dubbing is completed regardless of the position of the optical pickup 2 and whether it is in the read mode or the write mode.
The accumulation processing in the write channel buffer 13 corresponds to the stage after time T1 in FIG.
[0102]
Subsequently, when a predetermined condition determined by any one or a combination of two or more of the following factors (a) to (f) is satisfied, reading of the original data is stopped, and the switch 5 is again switched to the write channel buffer 13 side.
(A) Elapsed time from start of reading
(B) Amount of data stored in the read channel buffer 6
(C) Amount of data stored in the write channel buffer 13
(D) Media rate (read / write rate for the optical disc 19)
(E) Data rate of read channel and write channel (consumption rate of decoder 7, output rate of encoder 11)
(F) Capacity of buffers 6 and 13
[0103]
Finally, the address information of the original data sent to the read channel buffer 6 is stored. (When reading is resumed next time, based on this address information, the original data following the last data sent to the buffer 6 is read from the optical disc 19).
The switching of the switch 5 corresponds to the stage at time T2 in FIG.
[0104]
Subsequently, based on the information stored in advance in the system controller 14, the optical pickup 2 is not overlapped with the write start position (here, the portion R in FIG. 8 which is the recording position of the original data) from the current position X2. , The position of the optical pickup 2 is finely adjusted when the position approaches Y0.
[0105]
This seek operation corresponds to the stage from time T2 to T3 in FIG. Taking FIG. 8 as an example, the position of the optical pickup 2 changes from R to W by this seek operation.
[0106]
Then, the optical pickup 2, the RF, the demodulation / modulation circuit 3, and the ECC circuit 4 are switched to the write mode, and data is taken out from the write channel buffer 13. As a result, the post-recording audio data is written on the optical disc 19 after the error correction code is added.
[0107]
This write process corresponds to the stage from time T3 to T4 in FIG. 9, and the figure shows that the amount of data stored in the write channel buffer 13 decreases.
[0108]
Subsequently, when a certain condition determined by one or a combination of two or more of the elapsed time from the start of writing and the factors (b) to (f) is satisfied, the optical disc 19 is loaded. Data writing is stopped, and the switch 5 is switched again to the read channel buffer 6 side. Then, the address information of the last written data is stored. (When the next writing is resumed, the data following the last written data is taken out from the write channel buffer 13 based on this address information.)
The switching of the switch 5 corresponds to the stage at time T4 in FIG.
Up to the fourth step, one cycle of the after-recording operation is completed.
[0109]
Subsequently, based on the address information stored when the previous switch 5 is switched to the write channel buffer 13 side, the optical pickup 2 is sought from the current position Y1 to the position X2 where the previous reading was stopped.
[0110]
This seek operation corresponds to the stage from time T4 to T5 in FIG. Taking FIG. 8 as an example, the position of the optical pickup 2 changes from W to R by this seek operation. Thus, the position of the optical pickup 2 reciprocates between the reading position and the writing position.
[0111]
Then, the optical pickup 2, RF, demodulation / modulation circuit 3, and ECC circuit 4 are again switched to the reading mode, the position of the optical pickup 2 is finely adjusted, and reading by the optical pickup 2 is resumed. Hereinafter, until all of the after-recording data corresponding to the original data to be post-recorded is completed (or until the end of the post-recording is instructed by operation of an operation panel not shown), it is shown as a stage after time T5 in FIG. In addition, reading and writing as described above are performed in a time-sharing manner.
[0112]
[Fifth step]
As the final stage of post-recording, information indicating the temporal correspondence between the original data and post-recording audio data is recorded on the optical disc 19.
Here, as an example, a presentation time stamp (PTS) is used.
That is, as described above, in the MPEG2 system, since the packet of the bit stream of each medium has a presentation time stamp, the video bit stream V and the original data as shown in FIG. The presentation time of the portion of the main audio bitstream A1 that starts to correspond to the audio bitstream A2 that is post-recording audio data (that is, the head portion of the original data to be postrecorded specified by the user or specified information written on the optical disc 19) The time correspondence between the original data and the post-recording sound data is uniquely specified by the stamp.
[0113]
Therefore, when writing of the after-recording audio data corresponding to the original data to be dubbed is completed or when the user instructs the end of the after-recording, the system controller 14 presents a portion of the original data that starts to correspond to the after-recording audio data. Information indicating the time stamp is recorded in a TOC (Table Of Contents) area of the optical disc 19.
Also, the address information of the portion of the original data that starts to correspond to the post-recording audio data (X0 in FIG. 9) and the address information of the start position (Y0 in FIG. 9) and the end position of the post-recording audio data are also recorded in the TOC area. To do.
[0114]
Thus, as information indicating the temporal correspondence between the original data and the post-recording audio data, information indicating the presentation time stamp of the portion of the original data that starts to correspond to the post-recording audio data is recorded in the TOC area of the optical disc 19. Therefore, although the original data and the post-recording audio data are recorded without being multiplexed, the post-recording audio data is reproduced with the time exactly matched with the original data based on this information in the TOC. It becomes possible to do.
[0115]
FIG. 11 shows an example of the system configuration of an optical disc apparatus to which the reproducing method and apparatus of the present invention are applied when the after-recording method (3) is adopted.
In this optical disk apparatus, a single optical pickup (optical head) 31 for reading data is provided, and a bit stream read by the optical pickup 31 from an optical disk mounted on the optical disk apparatus is an RF and demodulation circuit. 32 (having the functions of the RF and demodulating circuit 21 in FIG. 6) and the ECC circuit 33 (having the function of the ECC circuit 22 in FIG. 6) are demodulated and error-corrected, respectively, via the switch 34, It is sent to a buffer 35 (any one of the buffer 35a of the channel (Ch) 1 and the buffer 35b of the channel (Ch) 2) for absorbing the difference between the reading rate and the decoding processing rate.
[0116]
The bit stream extracted from the Ch1 buffer 35a is decoded by a decoder 36a (including a demultiplexing unit, a video decoder, and an audio decoder) 36a. The video signal output from the decoder 36a is sent to a display (not shown) from the video output terminal P1, and the audio signal output from the decoder 36a is sent to the mixing circuit 37.
[0117]
On the other hand, the bit stream extracted from the Ch2 buffer 35 b is decoded by a decoder (including an audio decoder) 36 b, and the audio signal output from the decoder 36 b is sent to the mixing circuit 37.
The audio signal output from the mixing circuit 37 is sent from an audio output terminal P2 to a speaker (not shown) and reproduced.
[0118]
Although not shown, the TOC information read from the optical disk by the optical pickup 31 is demodulated and error-corrected by the RF and demodulation circuit 32 and the ECC circuit 33, respectively, and then sent to the system controller 38.
As will be described later, the system controller 38 controls the operation of each part of the optical disk apparatus during playback. Although not shown, the system controller 38 includes a CPU, a ROM storing a processing program to be executed by the CPU, and a processing process. It includes a RAM for temporarily storing generated data and the like. Of this control, the fine adjustment of the position of the optical pickup 31 is performed by detecting an address detection circuit 39 that takes in the bit stream demodulated by the RF and demodulation / modulation circuit 32 and detects the address information of the data currently being read. Based on the results.
[0119]
Next, an example of a process executed by the system controller 38 at the time of reproducing the optical disc 19 (the one that has been dubbed by the optical disc apparatus of FIG. 7) will be described.
[First step]
7 shows the presentation time stamp of the portion of the original data that starts to correspond to the post-recording audio data, which is the information recorded by the optical disc apparatus of FIG. 7 when the optical pickup 31 reads the TOC information of the optical disc 19. The information, the address information of the portion of the original data that starts to correspond to the post-recording voice data (X0 in FIG. 9), and the address information of the start position (Y0 in FIG. 9) and end position of the post-recording voice data are obtained.
[0120]
[Second step]
When the user designates the reproduction start position of the original data (video bit stream V and main audio bit stream A1 in FIG. 8) by operating an operation panel (not shown), the optical pickup 31 is reproduced based on the address information of the reproduction start position. Seek to the start position. Then, the switch 34 is switched to the Ch1 buffer 35a side to finely adjust the position of the optical pickup 31, and then reading by the optical pickup 31 is started.
Then, the original data stored in the buffer 35a is taken out from the buffer 35a and sent to the decoder 36a, and the decoding process in the decoder 36a is started.
[0121]
As a result, the original video is reproduced and the original sound is reproduced as it is through the mixing circuit 37.
Since the consumption rate of the decoder 36a is smaller than the reading rate from the optical disc 19, when the original data is accumulated in the buffer 35a to the full capacity, the reading of the original data from the optical disc 19 is interrupted and then from the buffer 35a. When the data 35 is taken out and there is sufficient space in the buffer 35a, reading from the optical disc 19 is resumed.
[0122]
In this way, when the original data is read out and reaches the portion (X0 in FIG. 9 and PTS portion in FIG. 10) having the same presentation time stamp as the presentation time stamp indicated by the information obtained in the first step, When the amount of data stored in the buffer 35a reaches the minimum required amount determined from the following factors (g) to (j), for example (the amount full), the original data is read out. At the same time, the extraction of the original data from the buffer 35a is stopped, and the switch 34 is switched to the buffer 35b side of Ch2. (G) Elapsed time since reaching the portion having the same presentation time stamp as the presentation time stamp indicated by the information obtained in the first step
(H) Media rate (read / write rate for the optical disc 19)
(I) Ch1 and Ch2 data rates (consumption rates of the decoders 36a and 36b)
(J) Capacity of buffers 35a and 35b
[0123]
Then, the address information of the original data finally sent to the buffer 35a is stored. (When resuming the reading of the original data next time, based on this address information, the original data following the data finally sent to the buffer 35a is read from the optical disc 19.)
[0124]
Subsequently, based on the address information obtained in the first step, the optical pickup 31 is sought from the current position to the start position of post-recording audio data (Y0 in FIG. 9), and the position of the optical pickup 31 is finely adjusted. Thereafter, reading by the optical pickup 31 is started.
Thereby, the after-recording audio data (sub audio bit stream A2 in FIG. 8) is accumulated in the buffer 35b.
[0125]
[Third step]
Subsequently, the amount of data stored in the buffer 35b is determined as the minimum necessary amount determined from the factors (h) to (j) and the following (k) and (l) (for example, the capacity is full). The original data and the post-recording audio data are respectively taken out from the Ch1 buffer 35a and the Ch2 buffer 35b and sent to the decoders 36a and 36b, and the decoding process in the decoder 36b is also started.
(K) Elapsed time since the start of post-recording audio data reading
(L) Amount of data stored in the buffer 35a of Ch1
The minimum required data accumulation amount for the buffer 35b may be smaller than the minimum necessary data accumulation amount for the buffer 35a. This is because the after-recording audio data is still being read out after the decoding process in the decoder 36b is started, so that the risk of underflow in the buffer 35b is reduced.
[0126]
Also, in this example, when the second step reaches a portion having the same presentation time stamp as the presentation time stamp indicated by the information obtained in the first step, the extraction of the original data from the buffer 35a of Ch1 is stopped (accordingly, The decoding process of the original data in the decoder 36a is stopped), and in the subsequent third step, the after-recording audio data is started to be extracted from the Ch2 buffer 35b and the decoding process of the after-recording audio data is started in the decoder 36b. The extraction of the original data from the buffer 35a is resumed (therefore, the decoding process of the original data in the decoder 36a is resumed). However, as another example, in the second step, even if a portion having the same presentation time stamp as that indicated by the information obtained in the first step is reached, the extraction of the original data from the buffer 35a is continued (hence the decoder). 36a), in the state where the decoding process in the decoder 36a is continued in this manner, in the third step, the post-recording audio data extraction from the buffer 35b is started and the decoder 36b The decoding process of post-recording audio data may be started.
[0127]
[Fourth step]
As a result, the original video is reproduced, and the original sound and the after-recording sound are mixed by the mixing circuit 37 and started to be reproduced.
[0128]
Subsequently, the after-recording audio data is read when a certain condition determined from the factors (h) to (j), (k), (l) and the following (m) is satisfied. The switch 34 is switched to the buffer 35a side of Ch1 again.
(M) Amount of data stored in Ch2 buffer 35b
Then, the address information of the post-recording audio data sent last to the buffer 35b is stored. (When re-reading of the after-recording audio data is resumed next time, the after-recording audio data following the data finally sent to the buffer 35b is read from the optical disc 19 based on this address information.)
[0129]
Subsequently, based on the address information stored when the previous switch 34 is switched to the Ch2 buffer 35b side, the optical pickup 31 is sought from the current position to the position of the original data where the previous reading was stopped. After finely adjusting the position 31, reading by the optical pickup 31 is started.
Hereinafter, until the reading of the post-recording audio data to the end position is completed (or until the user instructs the end of the reproduction by operating the operation panel not shown), the reading of the original data and the recording of the post-recording audio data as described above are performed. Reading and time division are performed.
[0130]
FIG. 12 shows an example of the reading state of the optical pickup 31 (A in the figure) and the data accumulation amounts (B and C in the figure) of the Ch1 buffer 35a and Ch2 buffer 35b in the steady state during reproduction. . In FIG. 12A, Ch1 is a period during which original data is being read, Ch2 is a period during which post-recording audio data is being read, Tp is a period during seek, Tc is a repetition period of time-division reading, and Rm Is a reading rate from the optical disc 19.
[0131]
In FIG. 12, at time T0, reading of original data is resumed before the amount of data stored in the buffer 35a becomes zero, and at time T1 thereafter, reading of original data is stopped, and between times T1 and T2 The optical pickup 31 is sought at the recording position of the after-recording audio data, and thereafter, at time T2, reading of the after-recording audio data is resumed before the amount of data stored in the buffer 35b becomes zero. Reading is stopped, the optical pickup 31 is sought to the recording position of the original data between times T3 and T4, and the same process is repeated thereafter.
[0132]
In FIG. 12, the relationship between the length of the original data reading period and the post-recording audio data reading period, and the relationship between the data storage amount of the buffer 35a and the data storage amount of the buffer 35b and the size thereof are discarded. I draw. However, since the original data consists of the video bit stream V and the main audio bit stream A1, the after-recording audio data consists only of the sub-audio bit stream A2, so the period during which the original data is being read is during the reading of the after-recording audio data. Of course, it is longer than the period, and the data accumulation amount of the buffer 35a may be larger than the data accumulation amount of the buffer 35b.
[0133]
In this way, information indicating the presentation time stamp of the portion of the original data that starts to correspond to the post-recording audio data is read from the TOC area of the optical disc 19, and based on this information, the original data and the post-recording audio data are synchronized. Since the original data and the post-recording audio data are recorded without being multiplexed at the time of the post-recording, the post-recording audio data is accurately matched in time with the original data. Played.
[0134]
In each of the above examples, reading and writing (or reading of two channels of data) is performed in a time-sharing manner by seeking one system of optical pickup, but reading and writing (or two systems) are provided. (Reading data of two channels) may be performed independently.
[0135]
In the above example, the present invention is applied to an optical disk device equipped with a rewritable optical disk. For example, an appropriate rewritable disk-shaped recording medium such as a magnetic disk (or a random access method other than the disk-shaped recording medium). The present invention may be applied to a recording / reproducing apparatus equipped with a digital recording medium). When two heads are provided, the present invention may be applied to a recording / reproducing apparatus equipped with a sequential access type digital recording medium such as a magnetic tape.
[0136]
In the above example, the present invention is applied to a recording medium in which original data is recorded by a packet multiplexing method. However, the present invention may be applied to a digital recording medium in which original data is recorded by an appropriate method.
[0137]
In the above example, the audio data is post-recorded on the original data consisting of the video bit stream V and the main audio bit stream A1, but the original data consisting of a bit stream of an appropriate media type is used. The present invention may be applied when post-recording new data of an appropriate type. That is, for example, when performing post-recording of at least one of audio data and graphic data on original data consisting only of a video bit stream (or consisting of a video bit stream and an audio bit stream), or from only an audio bit stream The present invention may also be applied to the case where after-recording of at least one of video data and graphic data is performed on the original data.
[0138]
Then, in the case of adopting the after-recording method of (3) described above, the mixing at the time of reproduction is performed not only for the main audio bit stream A1 and the sub audio bit stream A2 as in the optical disc apparatus of FIG. You may make it perform about the video bit stream of these, and the video bit stream or graphic bit stream of the after-recording data.
[0139]
Further, the present invention is not limited to the above-described embodiments, and it is needless to say that various other configurations can be taken without departing from the gist of the present invention.
[0140]
【The invention's effect】
As described above, according to the post-recording method and apparatus according to the present invention, the original data (Video bitstream and at least one audio bitstream) For the recording area of Voice for Since the temporal relationship of the data recording area is clarified, the effect that the dubbing data can be easily reproduced in time exactly with the original data when reproducing the video and audio as a completed work. Is obtained.
[0141]
Also , Information indicating the temporal correspondence between original data and post-record data Information indicating the presentation time stamp of the original data that begins to correspond to the post-record data But recoding media Because it is recorded in the additional information recording area, the original data and post-recording data are recorded without being multiplexed. Even Based on this information, it is possible to reproduce the after-recording data by accurately matching it with the original data in terms of time.
[0142]
Moreover, the claim concerning this invention 8 And 1 1 According to the reproduction method and apparatus described in It has recording areas for video bitstream, main audio bitstream, and sub audio bitstream Original data from the additional information recording area of the recording medium (Video bitstream and at least one audio bitstream) And dubbing voice As the information indicating the temporal correspondence with the data, voice Information indicating the presentation time stamp of the part that starts to correspond to the data is read, and based on this information, the original data and Written in the recording area of the sub-audio bitstream of the recording medium Dubbing voice Since the data is read and decoded synchronously, the original data and the after-recording voice Even if data is recorded without being multiplexed, voice There is an effect that the data can be reproduced with the original data accurately matched in time.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an example of a system configuration of an optical disc apparatus to which the present invention is applied.
FIG. 2 is a diagram illustrating an example of a relationship between a reading position and a writing position of an optical pickup.
FIG. 3 is a diagram illustrating an example of a relationship between a position of an optical pickup and a read / write situation and an amount of data stored in a buffer.
FIG. 4 is a block diagram showing another example of the system configuration of the optical disc apparatus to which the present invention is applied.
FIG. 5 is a diagram illustrating an example of recording data on a digital recording medium.
FIG. 6 is a diagram showing an example of a conventional post-recording process.
FIG. 7 is a block diagram showing an example of a system configuration of an optical disc apparatus to which the present invention is applied.
FIG. 8 is a diagram illustrating an example of a relationship between a reading position and a writing position of the optical pickup.
FIG. 9 is a diagram illustrating an example of a relationship between a position of an optical pickup and a read / write situation, and an amount of data stored in a buffer.
FIG. 10 is a diagram showing a presentation time stamp of a portion of original data that starts to correspond to post-recording audio data.
FIG. 11 is a block diagram showing another example of the system configuration of the optical disc apparatus to which the present invention is applied.
FIG. 12 is a diagram illustrating an example of a state of reading of an optical pickup and a data accumulation amount in a buffer during time-division reproduction.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,19 ... Optical disc, 2, 31 ... Optical pick-up, 3 ... RF and demodulation / modulation circuit, 4, 33 ... ECC circuit, 5, 10, 18, 34 ... Switch, 6 ... For read channel Buffer, 7, 36a, 36b Decoder, 8 Bypass buffer, 9 Detector, 11 Encoder, 12 Encoder buffer, 13 Write channel buffer, 14, 38 System controller, 15, 39 ... Address detection circuit, 16, 17 ... Work memory, 20 ... Multiplexer, 32 ... RF and demodulation circuit, 35a ... Ch1 buffer, 35b ... Ch2 buffer, 37 ... Mixing circuit

Claims (13)

A first step of reading a bitstream including a video bitstream and at least one audio bitstream from a recording medium having a recording area of a video bitstream, a main audio bitstream, and a sub audio bitstream ;
A second step of decoding the bitstream;
In synchronism with the decoding of the bitstream, a third step of encoding new audio data into a bitstream for after recording;
A fourth step of writing the bit stream for the after recording into a recording area of the sub audio bit stream of the recording medium;
As information indicating the temporal correspondence between the bit stream read from the recording medium and the bit stream for after recording, the bit stream for after recording out of the bit stream read from the recording medium and And a fifth step of writing information indicating a presentation time stamp of a portion that starts to correspond to an area for recording additional information of the recording medium. The recording medium is a disc-shaped recording medium rewritable, according to claim 1, characterized in that with said fourth step and said first step, when dividing the common read-write head After-recording method for recording media. In the second step, the bit stream is sent to a decoder and stored in a buffer, and in the fourth step, the bit stream taken out from the buffer and the bit stream for after recording are combined into the recording medium. 3. The after-recording method for a recording medium according to claim 1, wherein writing is performed. Wherein in the fourth step, the recording medium according to the bit stream for after recording, any one of claims 1 to 3, characterized in that writing without the bit stream and multiplexing read in the first step After recording method. Read means for reading a bit stream including a video bit stream and at least one audio bit stream from a recording medium having recording areas for the video bit stream, the main audio bit stream, and the sub audio bit stream ;
A decoder for decoding the bitstream read from the recording medium by the reading means;
An encoder for encoding new audio data into a bitstream for after-recording,
Writing means for writing the bit stream for after-recording to the recording medium;
Control for writing the after-recording bitstream encoded by the encoder in synchronization with the decoding of the bitstream by the decoder into the recording area of the sub-audio bitstream of the recording medium by controlling the writing means Means,
As information indicating the temporal correspondence between the bit stream read from the recording medium and the bit stream for after recording, the bit stream for after recording out of the bit stream read from the recording medium and An after-recording apparatus for a recording medium, comprising: additional information writing means for writing information indicating a presentation time stamp of a portion that starts to correspond to an area for recording additional information of the recording medium. The recording medium is a rewritable disc-shaped recording medium,
The reading means and the writing means are a common read / write head,
6. The after recording apparatus for a recording medium according to claim 5 , wherein the control means causes the bit stream for the after recording to be written using the read / write head in a time division manner. The after-recording apparatus for a recording medium according to claim 5 or 6 , wherein the control means causes the bit stream for after-recording to be written without being multiplexed with the bit stream read by the reading means. . Includes a video bit stream and at least one audio bit stream that are subject to after recording from a recording area of additional information of a recording medium having recording areas of a video bit stream, a main audio bit stream, and a sub audio bit stream As the information indicating the temporal correspondence between the bit stream of the original data and the bit stream of the audio data for after recording written without being multiplexed with the bit stream of the original data, the after data of the original data A first step of reading information indicating a presentation time stamp of a portion that starts to correspond to the audio data for recording;
A second step of synchronously reading out the bit stream of the original data and the bit stream of the after-recording audio data written in the recording area of the sub-audio bit stream of the recording medium based on the information;
And a third step of decoding the bit stream of the original data and the bit stream of the audio data for after-recording. A method of reproducing an after-recorded recording medium, comprising: 9. The after-recorded recording medium according to claim 8 , further comprising a fourth step of mixing the bit stream of the original data decoded in the third step and the bit stream of the after-recording data. Playback method. The method of reproducing an after-recorded recording medium according to claim 8 or 9 , wherein the recording medium is a disk-shaped recording medium, and the second step is performed by using one read head for time division. . Read means for reading a bit stream from a recording medium having recording areas for a video bit stream, a main audio bit stream, and a sub audio bit stream ;
A bit stream of original data including a video bit stream and at least one audio bit stream, which is a target of after-recording, from the recording area of the additional information of the recording medium, and the bit stream of the original data Is a presentation time stamp of a portion of the original data that starts to correspond to the after-recording audio data as information indicating a temporal correspondence with the bit stream of the after-recording audio data written without being multiplexed to read the information indicating, on the basis of the information, the control the reading means, and a bit stream of the original data, wherein the after-record written to the recording area of the sub-audio bitstream of said recording medium And control means for read out is synchronized with the bit stream of the audio data for loading,
An after-recorded recording medium playback apparatus, comprising: a decoder for decoding the bit stream read from the recording medium by the reading means. Playback after recording by the recording medium of claim 1 1, characterized in that said decoder further comprises a mixing means for mixing the bit stream of the bit stream of the original data decoded the after-recording data apparatus. The recording medium is a disk-shaped recording medium;
The reading means is one reading head;
The control means according to claim 1 1 or 1 2, characterized in that to read the bit stream of the after-recording data and a bit stream of the original data using the time division the one read head Of after-recorded recording media.

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