JP2002354419A - Recording reproducing equipment and method therefor, recording medium and program thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To output a smoothly changing image and sound synchronous to the image, in special reproduction. SOLUTION: In step S1, a program stream is read at a speed two or more times an ordinary value. In step S2, a DTS value and a PTS value of each frame are obtained from the program stream. In step S3, the DTS value and the PTS value are offset corresponding to a reproduction speed of the special reproduction, and a DTS offset value and a PTS offset value are produced. In a step S4, the PTS value and the DTS value of an image frame included in the program stream, and the PTS value of a sound frame are rewritten to be a PTS offset value and a DTS offset value. In a step S5, each of the rewritten PTS value and DTS value is compared with an STC counter value, and the timing of decode and the timing of output are controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus and method, a recording medium, and a program.
The present invention relates to a recording / reproducing apparatus and method, a recording medium, and a program suitable for use in performing special reproduction of an encoded AV signal data stream.

[0002]

2. Description of the Related Art Moving Picture Experts MPEG (MPEG) is used as a method for compressing and encoding video and audio signals with high efficiency.
roup) There are two methods. A video and audio data stream encoded according to the MPEG2 system is called an elementary stream. The elementary stream is a PES (Packetized ElementaryS) having common reference time information.
A stream is converted into a program stream by being divided and incorporated into a data structure called a packet.

A transport stream is a single bit string in which one or more program streams are multiplexed, and is used in digital CS broadcasting, digital BS broadcasting, and the like.

[0004] In the MPEG2 system, each video frame constituting a video signal is categorized into one of an I picture, a P picture, and a B picture and encoded. I picture is
It is encoded using only the information of its own video frame (intra-picture encoding). P picture is
It is coded based on forward inter-picture predictive coding. The B picture is encoded by bidirectional predictive encoding using information on forward and backward video frames.

A video signal coded according to the MPEG2 system is, for example, a GOP (Group of Pic
ture), random access is possible. GOP
Contains at least one video frame containing an intra-coded I picture.

A transport stream composed of a program stream encoded by the MPEG2 system (hereinafter, referred to as a transport stream)
MPEG2-TS) includes a PC so that video and audio can be reproduced at the timing intended by the transmitting side such as a broadcasting station.
A program time reference reference value called R (Program Clock Reference), time management information for reproduction called PTS (Presentation Time Stamp), and DTS (Decoding Tim
Time management information for decoding called “e Stamp” is added. PCR sets the reference time on the sending side,
Information for calibration, which is embedded in the transto stream and transmitted. PTS and DTS are information indicating the timing of reproduction and the timing of decoding, respectively, and are transmitted by being embedded in the header information of PES.

On the receiving side such as a set-top box, a PCR is acquired at the time of channel switching or the like, and a value indicated by the PCR (hereinafter referred to as a PCT value) is stored in its own STC (System Time).
Clock) counter. Thereafter, every time a PCR is acquired, the acquired PCR value and the value of the STC counter (hereinafter, STC
Then, the reference time intended by the transmitting side is restored on the reproducing side by fine-tuning the clock of the STC counter so that the two coincide with each other.

[0008] The stream is decoded at a timing when the value indicated by the DTS (hereinafter, referred to as the DTS value) matches the STC counter value.
This is performed at the timing when the S value matches the STC counter value.
Thereby, the video and the audio are reproduced on the reproducing side in the sequence and the time interval intended by the transmitting side.

FIG. 1 shows an example of the configuration of a recording and reproducing apparatus for recording and reproducing MPEG2-TS. In the recording / reproducing apparatus, the input MPEG2-TS is supplied to the TS parser 1 and the terminal a of the switch 2.

[0010] The TS parser 1 extracts a program stream to be recorded from the MPEG2-TS and supplies it to the writing unit 4 of the recording / reproducing unit 3. The writing unit 4 includes the TS parser 1
Is recorded on a recording medium 5 such as a hard disk drive. The reading unit 6
The program stream recorded on the recording medium 5 is read and supplied to the terminal b of the switch 2.

[0011] The switch 2 is provided for the MPEG2 supplied to the terminal a.
-Output the TS or the program stream supplied to the terminal b to the PCR acquisition unit 7 and the PES parsers 8 and 9. Hereinafter, MPEG2-TS output from the switch 2 to the subsequent stage,
Alternatively, the program stream is simply described as a stream.

The PCR acquisition section 7 extracts a PCR from the stream output by the switch 2 and outputs the extracted PCR to the control section 10.
The control unit 10 compares the PCR value with the STC counter value of the STC counter 12, and when the two values are different from each other,
Set to 2. The clock generator 11 oscillates a clock signal for counting up the STC counter 11 and supplies the clock signal to the STC counter 12. The STC counter 12
The PCR value supplied from the control unit 10 is set, and the value is counted up in synchronization with the clock signal supplied from the clock generation unit 11. The STC counter value is supplied to the comparator 16 of the video decoder 13 and the comparator 21 of the audio decoder 18.

The PES parser 8 stores video frame data from the stream output from the switch 2.
The PES is extracted and output to the input buffer 14 of the video decoder 13. The input buffer 14 receives the PES from the PES parser 8
Are buffered for a predetermined time, and then output to the PTS / DTS acquisition unit 15 and the video decoding unit 17. PTS / DTS
The acquisition unit 15 extracts PTS and DTS from the PES packet and outputs the PTS and DTS to the comparator 16.

The comparator 16 compares the PTS value and the DTS value with the STC counter value. If the DTS value and the STC counter value match, the time is the timing of decoding the corresponding PES packet. To the video decoding unit 17
When the PTS value matches the STC counter value, the video decoding unit 17 is notified that the time is the output timing of the corresponding PES packet. The video decoding unit 18 decodes and outputs the corresponding PES packet from the input buffer 14 in synchronization with the timing notified from the comparator 16.

The PES parser 9 stores voice frame data from the stream output from the switch 2.
The PES is extracted and output to the input buffer 19 of the audio decoder 18. The input buffer 19 receives the PES from the PES parser 9
After buffering for a predetermined time, the PTS acquisition unit 2
0 and output to the audio decoding unit 22. PTS acquisition unit 2
0 extracts the PTS from the PES packet and outputs it to the comparator 21.

The comparator 21 compares the PTS value with the STC counter value. If the PTS value and the STC counter value match, the comparator 21 informs the audio decoding unit 22 that the time is the output timing of the corresponding PES packet. Notice. Audio decoding unit 2
2 decodes and outputs the corresponding PES packet from the input buffer 19 in synchronization with the timing notified from the comparator 21.

Next, the video decoder 1 of the recording / reproducing apparatus
3 and the operation of reproducing the stream by the audio decoder 18 will be described with reference to FIG.

The horizontal axis of FIG. 2 shows the STC counter value. In the figure, I1, B1, P1 and the like indicate a video frame of an I picture, a video frame of a B picture, or a video frame of a P picture, respectively, and the subscript numerical value (“1” of I1) is the same. The order of the display output in the type of picture is shown.

FIG. 2A shows the first video stream included in the video stream input from the PES parser 8 to the video decoder 13.
It shows the input timing of a video frame that forms part of a GOP (GOP1) and a subsequent second GOP (GOP2).
For example, a video frame I1 of an I picture is input to the video decoder 13 at a timing when the STC counter value is 3994. Also, it is shown that the video frame B1 of the B picture is input to the video decoder 13 at the timing when the STC counter value is 6997. It is assumed that the DTS value (decode timing) and the PTS value (output timing) of each video frame are as shown.

FIG. 2B shows an input timing of an audio frame of an audio stream input from the PES parser 9 to the audio decoder 18. For example, an audio frame A1 corresponding to a video frame I1 of an I picture has an audio decoder 1 at a timing when the STC counter value is 3994.
8 is input. The audio frame A2 corresponding to the video frame B1 of the B picture is an STC.
This shows that the counter value is input to the audio decoder 18 at the timing of 6997. It is assumed that the PTS value (output timing) of each audio frame is as shown.

Note that the PTS of video frames and audio frames
For example, in the case of BS digital broadcasting, the value and the DTS value are set by incrementing 3003 for consecutive frames.

The relationship between the decoding order of the video stream and the DTS value will be described with reference to FIG. FIG.
(C) shows the decoding timing of the video frame. Since the video frame I1 is a video frame to be decoded first in the first GOP, it is the smallest video frame.
DTS value is set. Since the subsequently input video frames B1 and B2 are bidirectionally predictive coded, the information of the preceding and succeeding video frames is used for decoding. Therefore, it is necessary to decode the succeeding video frame P1 first. Therefore, the DTS value is set so that the value increases in the order of the video frames P1, B1, and B2.

According to the DTS set as described above, the input video stream has an STC counter value of 3994.
The video frame I1 is decoded at the timing
Next, at the timing when the STC counter value is 13003, the video frame P1 is decoded using the already decoded video frame I1. Further, at the timing when the STC counter value is 16006, the video frame B
1 is the already decoded video frame I1, P1
Is decoded by using.

The relationship between the order of video stream display output and the PTS value will be described with reference to FIG. FIG.
(D) shows the display output timing of the video frame. The order of the video output is the same as the order of the input timing shown in FIG. Therefore, the PTS value is
300 in the order of video frames I1, B1, B2,.
A value that is incremented by three is set.

As for the display of the input video stream, the decoded video frame I1 is displayed and output at the timing when the STC counter value is 13003. Next, the decoded video frame B1 is displayed and output at a timing when the STC counter value is 16006. Further, the decoded video frame B2 is displayed and output at a timing when the STC counter value is 19,099.

As shown in FIG. 2E, the order of the input timing, the order of the decode timing, and the order of the output timing of the audio stream corresponding to the video stream are the same. Therefore, the audio stream is decoded and output in the order of the audio frames A1, A2, A3,... At the timing when the set PTS value matches the STC counter value.

In the conventional recording / reproducing apparatus, when performing special reproduction such as fast forward reproduction or rewind reproduction, the reading section 6
Reads out the stream at a predetermined speed higher than usual, the PES parser 8 extracts only the I-picture video frame from the video frames and supplies it to the video decoder 13, and the video decoder 13 outputs the PTS value and the DTS Instead of controlling the decode timing and the display output timing by comparing the value with the STC counter value, this is realized by sequentially decoding the input I-picture video frames and displaying and outputting them.

Referring to FIG. 3, a description will be given of double-speed fast-forward reproduction by a conventional recording / reproducing apparatus. Figure (A)
Are the video frames I1, I2, of the extracted I picture
The timing at which I3 is input to the video decoder 13 is shown. It is assumed that the DTS value and the PTS value set for the I picture are as illustrated. FIG. 3B shows the decoding timing of the I picture. FIG.
The display output timing of the I picture is shown.

As shown in FIGS. 3B and 3C, the video frames I1, I2, and I3 are composed of the set DTS value and PTS.
Regardless of the value, it is decoded and displayed at the time of input. For example, the video frame I1 is decoded and displayed at a timing when the STC counter value is 3994. The video frame I2 is decoded at the timing when the STC counter value is 25015, and is displayed and output. Further, the video frame I3 is decoded at the timing when the STC counter value is 46036, and is displayed and output.

If attention is paid to the interval between the timings at which the video frames I1, I2 and I3 are displayed and output in the double-speed fast-forward reproduction, the interval between the display outputs between the video frames is 21021.
It is. This value is 45045 (= video flake I2), which is the interval when normal reproduction (1 × speed reproduction) is performed.
PTS value (58048)-PTS value of video flake I1 (1
3003)). That is, it can be seen that the reproduction is realized at twice the normal reproduction.

[0031]

In the operation of digital broadcasting such as digital CS broadcasting and digital BS broadcasting, a GOP included in a stream is composed of 15 video frames (15 pictures), of which only one video frame is provided. Is an I picture. That is, the I picture is only 1/15 of all the video frames.

Therefore, when special reproduction is performed at a speed of, for example, 15 times or less by the conventional recording / reproducing apparatus, the video does not change smoothly and becomes jerky like frame advance. there were.

In consideration of outputting audio along with video, during special playback, as described above, control of decode timing and display output timing based on the PTS value and DTS value and the STC counter value is performed. Since it is not performed, there is a problem that it is difficult to synchronize video and audio.

The present invention has been made in view of such a situation. In the case of performing special reproduction, the PTS of all video frames regardless of the type of video frame (I picture, B picture, and P picture). It is an object of the present invention to be able to output a video that smoothly changes and an audio synchronized with the video by rewriting a value and a DTS value and rewriting a PTS value of all audio frames.

[0035]

A recording / reproducing apparatus according to the present invention comprises a reading means for reading a data stream from an information recording medium, and a first means for indicating a decoding timing of the data stream from the data stream read by the reading means. Acquisition means for acquiring information and second information indicating output timing, and generation for offsetting the first and second information acquired by the acquisition means to generate first offset information and second offset information. Means for replacing the first and second information included in the data stream with the first and second offset information generated by the generating means, and a data stream including the first and second offset information. Decoding means for decoding and reproducing a video signal and an audio signal.

[0036] The recording / reproducing apparatus of the present invention may further include adjusting means for extracting reference time information for adjusting the reference time from the data stream and adjusting the reference time.

The generating means generates first offset information and second offset information using the first and second information obtained by the obtaining means, a reference time, and a coefficient corresponding to the reproduction speed. You can do so.

According to the recording / reproducing method of the present invention, there are provided a reading step for reading a data stream from an information recording medium, and first information indicating a decoding timing of the data stream and output timing from the data stream read in the processing of the reading step. An acquisition step of acquiring second information indicating the following, and a generation step of offsetting the first and second information acquired in the processing of the acquisition step to generate first offset information and second offset information. , A first and a second included in the data stream
Replacing the information with the first and second offset information generated in the processing of the generation step, and decoding a data stream including the first and second offset information to reproduce a video signal and an audio signal. Decoding step.

The program of the recording medium according to the present invention comprises: a reading step of reading a data stream from an information recording medium; and a first information indicating a decoding timing of the data stream and an output from the data stream read in the processing of the reading step. An acquisition step of acquiring second information indicating a timing; and offsetting the first and second information acquired in the processing of the acquisition step to obtain a first information.
Generating the offset information and the second offset information, and replacing the first and second information included in the data stream with the first and second offset information generated in the processing of the generating step. And a decoding step of decoding a data stream including the first and second offset information to reproduce a video signal and an audio signal.

The program according to the present invention comprises a reading step of reading a data stream from an information recording medium, and a first step indicating a decoding timing of the data stream from the data stream read in the processing of the reading step.
Obtaining the first information and the second information indicating the output timing; and offsetting the first and second information obtained in the processing of the obtaining step to obtain the first offset information and the second offset information. A generating step of generating; a replacing step of replacing the first and second information included in the data stream with the first and second offset information generated in the processing of the generating step;
And decoding a data stream including the second offset information and reproducing a video signal and an audio signal.

In the recording / reproducing apparatus, method, and program according to the present invention, a data stream is read from an information recording medium, and a first timing indicating a decoding timing of the data stream is read from the read data stream.
And the second information indicating the output timing are obtained, and the obtained first and second information are offset to generate first offset information and second offset information. In addition, the first stream included in the data stream
And the second information are replaced with the generated first and second offset information. In addition, the first and second
Is decoded, and the video signal and the audio signal are reproduced.

[0042]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A configuration example of a recording / reproducing apparatus according to an embodiment of the present invention will be described with reference to FIG.
This recording / reproducing apparatus records a program stream included in an input MPEG2-TS, reads and decodes the same, outputs the obtained video and audio, and also converts a program stream included in the input MPEG2-TS in real time. And outputs the obtained video and audio. Further, the recording / reproducing apparatus performs special reproduction of the read program stream.

In this recording / reproducing apparatus, the input MP
The EG2-TS is supplied to the TS parser 31 and the terminal a of the switch 32. The TS parser 31 extracts a program stream to be recorded from the MPEG2-TS, and supplies the program stream to the writing unit 34 of the recording / reproducing unit 33. Writing unit 34
Records the program stream from the TS parser 31 on a recording medium 35 such as a hard disk drive. The reading unit 36 reads the program stream recorded on the recording medium 35 and reads the program stream from the PTS / DTS acquisition unit 3.
7 and output to the PTS / DTS rewriting unit 39.

The PTS / DTS acquisition unit 37 converts the program stream input from the reading unit 36
The DTS value and the PTS value are obtained and output to the PTS / DTS calculation unit 38. The PTS / DTS calculation unit 38 offsets the DTS value and the PTS value from the PTS / DTS acquisition unit 37 in accordance with the playback speed of trick play, and converts the obtained DTS offset value and PTS offset value into a PTS / DTS rewrite unit. Output to 39.

The PTS / DTS rewriting unit 39 includes the reading unit 3
The PTS value and the DTS value of each frame included in the program stream input from the PTS 6 are rewritten to the PTS offset value and the DTS offset value input from the PTS / DTS operation unit 38, and are supplied to the terminal b of the switch 32.

The switch 32 outputs the MPEG signal supplied to the terminal a.
2-TS or the program stream supplied to the terminal b is output to the PCR acquisition unit 40 and the PES parsers 41 and 42. Hereinafter, MPEG2 output by the switch 32 to the subsequent stage
-A TS or a program stream is simply described as a stream.

The PCR acquisition section 40 extracts a PCR from the stream output from the switch 32 and outputs the extracted PCR to the control section 43. The control unit 43 reads a control program stored in a recording medium 56 including a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, and the like, and based on the read control program, a command input by a user, and the like, It controls the entire recording and playback device. Further, the control unit 43 compares the PCR value with the STC counter value of the STC counter 45, and sets the PCR value in the STC counter 45 when the two are different.

The clock generator 44 includes an STC counter 45
Oscillates a clock signal to count up
It is supplied to the STC counter 45. The STC counter 45 sets the PCR value supplied from the control unit 43, and counts up the value in synchronization with the clock signal supplied from the clock generation unit 44. The STC counter value is supplied to the PTS / DTS operation unit 38 of the recording / reproducing unit 33, the comparator 16 of the video decoder 13, and the comparator 21 of the audio decoder 18.

The PES parser 41 extracts the PES storing the video frame data from the stream output from the switch 32 and outputs the PES to the input buffer 4 of the video decoder 46.
7 is output. The input buffer 47 buffers the PES of the PES parser 41 and the like for a predetermined time, and then sets the PTS / DT
The signal is output to the S acquisition unit 48 and the video decoding unit 50. PTS
The DTS acquisition unit 48 extracts the PTS and the DTS from the PES packet and outputs the PTS and the DTS to the comparator 49.

The comparator 49 compares the PTS value and the DTS value with the STC counter value. If the DTS value matches the STC counter value, a pulse indicating the timing of decoding the corresponding video frame. Video decoding unit 5
When the PTS value matches the STC counter value, a pulse indicating the timing of the display output of the corresponding video frame is output to the video decoding unit 50. The video decoding unit 50 decodes and displays and outputs the corresponding video frame from the input buffer 14 in synchronization with the pulse from the comparator 49.

The PES parser 42 extracts, from the stream output from the switch 32, the PES in which the data of the audio frame is stored, and extracts the PES from the input buffer 5 of the audio decoder 51.
Output to 2. The input buffer 52 buffers the PES from the PES parser 42 for a predetermined time, and then outputs the PES to the PTS acquisition unit 53 and the audio decoding unit 55. The PTS acquisition unit 53 extracts the PTS from the PES packet and outputs the PTS to the comparator 54.

The comparator 54 compares the PTS value with the STC counter value. If the PTS value and the STC counter value match, the comparator 54 outputs a pulse indicating the timing of decoding and outputting the corresponding audio frame. Output to 55.
The audio decoding unit 55 decodes and outputs a corresponding audio frame from the input buffer 19 in synchronization with the pulse from the comparator 54.

Next, FIG. 5 shows the PTS offset value and DTS
3 shows a configuration example of a PTS / DTS calculation unit 38 that calculates an offset value.

In the PTS / DTS operation section 38, the PTS value from the PTS / DTS acquisition section 37 is input to a subtracter 67, and the PTS / DTS
The DTS value from the DTS acquisition unit 37 is input to the subtractor 64 and the DTS value memory 61, and the STC counter value from the STC counter 45 is input to the STC counter value memory 63.

The DTS value memory 61 holds a DTS value corresponding to a newly input video frame of the I picture among the input DTS values, and subtracts the held DTS value from the subtracters 64 and 67.
Output to

The coefficient memory 62 supplies the coefficient K corresponding to the reproduction speed to the multipliers 65 and 68. When the reproduction speed is X times, the coefficient K = 1 / X. For example,
In the case of double-speed fast-forward playback, the coefficient K is 1/2. Further, for example, in the case of 1/4 speed slow reproduction, the coefficient K =
It becomes 4.

The STC counter value memory 63 holds the STC counter value input from the STC counter value 45 at that time in synchronization with the timing when the DTS value memory 61 holds the DTS value, and stores the held STC counter value. Output to adders 66 and 69.

The subtracter 64 subtracts the DTS value held in the DTS value memory 61 from the DTS value corresponding to each frame sequentially input from the PTS / DTS acquisition unit 37, and outputs the operation result to the multiplier 65. I do. The multiplier 65 multiplies the operation result of the subtractor 64 by a coefficient K, and outputs the operation result to the adder 66. The adder 66 adds the STC counter value held in the STC counter value memory 63 to the operation result of the multiplier 65,
The calculation result is output to the PTS / DTS rewriting unit 39 as a DTS offset value.

The subtracter 67 subtracts the DTS value held in the DTS value memory 61 from the PTS value corresponding to each frame sequentially input from the PTS / DTS acquisition unit 37, and outputs the operation result to the multiplier 68. I do. Multiplier 68 multiplies the operation result of subtractor 67 by coefficient K, and outputs the operation result to adder 69. The adder 69 adds the STC counter value held in the STC counter value memory 63 to the operation result of the multiplier 68,
The calculation result is output to the PTS / DTS rewriting unit 39 as a PTS offset value.

Therefore, the PTS offset value and the DTS offset value are calculated by the following equations (1) and (2). PTS offset value = K (PTS value of each frame−DTS value held by DTS value memory 61) + STC counter value held by STC counter value memory 63 (1) DTS offset value = K (DTS value of each frame) −DTS value held in DTS value memory 61) + STC counter value held in + STC counter value memory 63 (2)

Next, the special reproduction process by the recording / reproducing apparatus to which the present invention is applied will be described with reference to the flowchart of FIG.

In step S1, the reading section 36
Reads the program stream recorded on the recording medium 35 at a reading speed that is twice or more the normal reading speed,
Output to the S / DTS acquisition unit 37 and the PTS / DTS rewriting unit 39. In step S2, the PTS / DTS acquisition unit 37
Acquires the DTS value and PTS value of each frame from the program stream input from the
• Output to the DTS calculation unit 38.

In step S3, the PTS / DTS operation unit 3
8 represents the DTS value and the PTS value from the PTS / DTS acquisition unit 37,
Offset corresponding to the playback speed of trick play
The DTS offset value and the PTS offset value are output to the PTS / DTS rewriting unit 39.

FIG. 7 shows the details of the processing in step S3.
This will be described with reference to FIG.

The horizontal axis of FIG. 7 shows the STC counter value. FIG. 7A illustrates a first GOP (GOP1) of a video stream read from the reading unit 36 and a second GOP subsequent thereto.
It shows the input timing of a video frame that forms part of a GOP (GOP2). For example, the video frame I1 is ST
This indicates that the C counter value was read at a timing of 3994. Also, the video frame B1 is an STC
This indicates that the counter value was read at a timing of 5496. Note that the DTS value (decode timing) and PTS value (output timing) of each video frame
Is as shown in the figure.

FIG. 7B shows the input timing of the audio frames constituting the audio stream read from the reading section 36. For example, the audio frame A1 corresponding to the video frame I1 has an STC counter value of 3994.
At a certain timing. The audio frame A2 corresponding to the video frame B1 is
This indicates that the STC counter value was read at a timing of 5496. It is assumed that the PTS value (output timing) of each audio frame is as shown.

The PTS / DTS calculation unit 38 is a PTS / DTS acquisition unit 3
7 is offset as shown in equation (1), and the DTS value from the PTS / DTS acquisition unit 37 is offset as shown in equation (2).

For example, the PTS offset value of the video frame I1 is calculated according to equation (1) as follows: PTS offset value = 0.5 (13003-3994) + 3994 = 8499.

The DTS offset value of the video frame I1 is
According to equation (2), DTS offset value = 0.5 (3994-3994) + 3994 = 3994 is calculated.

Further, for example, the PTS offset value of the video frame B1 is calculated according to equation (1) as follows: PTS offset value = 0.5 (16006-3994) + 3994 = 10000.

The DTS offset value of the video frame B1 is
According to equation (2), DTS offset value = 0.5 (16006-3994) + 3994 = 10000 is calculated.

Further, for example, the PTS of the video frame P1
The offset value is calculated as PTS offset value = 0.5 (22012-3994) + 3994 = 130003 according to equation (1).

The DTS offset value of the video frame P1 is
According to equation (2), DTS offset value = 0.5 (13003-3994) + 3994 = 8499 is calculated.

Similarly, the PTS offset value and DTS offset value of each video frame are calculated as shown in FIG. For audio frames, PT
Only the offset value of the S value is calculated as shown in FIG.

Returning to FIG. In step S4, the PTS
The DTS rewriting unit 39 is a PTS of a video frame included in the program stream input from the reading unit 36.
The value and the DTS value and the PTS value of the voice frame are rewritten to the PTS offset value and the DTS offset value input from the PTS / DTS calculation unit 38. The stream in which the PTS value and the DTS value have been rewritten is supplied to the subsequent stage via the terminal b of the switch 32.

In step S5, the PES parser 41
Extracts the PES storing the video frame data from the stream from the switch 32 and outputs it to the input buffer 47 of the video decoder 46. Input buffer 47
After buffering the PES from the PES parser 41 for a predetermined time, the PES is output to the PTS / DTS acquisition unit 48 and the video decoding unit 50. The PTS / DTS acquisition unit 48 extracts PTS and DTS from the PES packet and outputs the PTS and DTS to the comparator 49. The comparator 49 compares each of the PTS value and the DTS value with the STC counter value. If the DTS value and the STC counter value match, the comparator 49 decodes a pulse indicating the timing of decoding the corresponding video frame. Output to unit 50, PT
When the S value and the STC counter value match, a pulse indicating the timing of display output of the corresponding video frame is output to the video decoding unit 50. The video decoding unit 50
The input buffer 14 is synchronized with the pulse from the comparator 49.
And decodes and outputs the corresponding video frame. The order of the video frame decoding timing and the display output timing is as shown in FIG.

On the other hand, the PES parser 42 extracts the PES storing the data of the audio frame from the stream from the switch 32 and outputs the extracted PES to the input buffer 52 of the audio decoder 51. The input buffer 52 is a PES parser 42
After buffering these PESs for a predetermined time, they are output to the PTS acquisition unit 53 and the audio decoding unit 55. The PTS acquiring unit 53 extracts the PTS from the PES packet and
Output to The comparator 54 compares the PTS value with the STC counter value. If the PTS value matches the STC counter value, the comparator 54 outputs a pulse indicating the timing of decoding and outputting the corresponding audio frame to the audio decoding unit 55. I do.
The audio decoding unit 55 decodes and outputs a corresponding audio frame from the input buffer 19 in synchronization with the pulse from the comparator 54. The order of the decoding timing of the audio frame and the display output timing is shown in FIG.
As shown in FIG.

As described above, in the special reproduction processing by the recording / reproducing apparatus to which the present invention is applied, all video frames can be displayed and output regardless of the type of video frame. Also, corresponding to the playback speed,
Since the PTS value and DTS value and the PTS value of the corresponding audio frame are rewritten, the video and the audio can be output in synchronization.

The value of the coefficient K in the processing of the PTS / DTS calculation section 38 in step S3 can be changed in accordance with the operation of the user. If the coefficient K is set to 1, normal reproduction is performed. If the value of the coefficient K is 3, then
1/3 speed slow reproduction is executed.

As described above, according to the recording / reproducing apparatus to which the present invention is applied, the video of all video frames is displayed,
Since the audio of the audio frame is output in synchronization with it,
The usability of the user is improved by searching for a scene to be viewed.

Further, it is possible to view the content in a shorter time by the fast-reproduction reproduction, and to slowly view the hard-to-recognize part by the slow-reproduction reproduction.

Incidentally, the above-described series of processing can be executed by hardware, but can also be executed by software. When a series of processing is executed by software, a program constituting the software can execute various functions by installing a computer built into dedicated hardware or installing various programs. It is installed from a recording medium into a possible general-purpose personal computer or the like.

As shown in FIG. 4, this recording medium is a magnetic disk (including a floppy disk) on which the program is recorded and an optical disk (CD) which are distributed separately from the computer to provide the program to the user. -ROM (C
ompact Disc-Read Only Memory), DVD (Digital Versati
le Disc), magneto-optical disc (MD (Mini Disc)
), Or a package medium such as a semiconductor memory, as well as a ROM or a hard disk in which a program is recorded and provided to a user in a state of being incorporated in a computer in advance.

In this specification, the steps of describing the program recorded on the recording medium are not limited to the processing performed in chronological order according to the described order, but are not necessarily performed in chronological order. Alternatively, it also includes individually executed processing.

[0085]

As described above, according to the recording / reproducing apparatus, method, and program of the present invention, the first information indicating the decoding timing of the data stream and the second information indicating the output timing obtained from the data stream. The information is offset to generate first offset information and second offset information, and the first and second information are replaced with the generated first and second offset information. Thus, it is possible to output a smoothly changing video and audio synchronized with the video.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a configuration of a conventional recording / reproducing apparatus that records and reproduces MPEG2-TS.

FIG. 2 is a diagram for explaining a normal reproducing operation by a conventional recording / reproducing apparatus.

FIG. 3 is a diagram for explaining a 2 × speed reproduction operation by a conventional recording / reproducing apparatus.

FIG. 4 is a block diagram illustrating a configuration example of a recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 5 is a block diagram illustrating a configuration example of a PTS / DTS calculation unit 38.

FIG. 6 is a flowchart illustrating a special reproduction operation performed by the recording / reproduction device according to an embodiment of the present invention.

FIG. 7 is a diagram for explaining the calculation of a PTS offset value and a DTS offset value by a PTS / DTS calculation unit 38;

[Explanation of symbols]

37 PTS / DTS acquisition unit, 38 PTS / DTS calculation unit, 3
9 PTS / DTS rewrite unit, 43 control unit, 45 ST
C counter, 46 video decoder, 51 audio decoder, 56 recording medium

Continued on front page F term (reference) 5C052 AB04 AC05 CC11 DD04 DD10 5C053 FA20 FA30 GA11 GB05 GB38 HA24 JA22 KA01 KA08 KA22 KA24 LA00 LA06 LA07 5D044 AB07 BC01 CC05 DE28 DE48 FG09 FG18 GK12

Claims (6)

[Claims] 1. A recording / reproducing apparatus for recording and reproducing a data stream of an encoded AV signal, comprising: reading means for reading the data stream from an information recording medium; and the data stream read by the reading means. An acquisition unit for acquiring first information indicating a decode timing of the data stream and second information indicating an output timing, and offsetting the first and second information acquired by the acquisition unit, Generating means for generating first offset information and second offset information; and converting the first and second information included in the data stream into the first and second offsets generated by the generating means. Replacement means for replacing the first and second offset information with each other; It decodes the over arm, the recording and reproducing apparatus characterized by comprising a decoding means for reproducing video signals and audio signals. 2. The recording / reproducing apparatus according to claim 1, further comprising: adjusting means for extracting reference time information for adjusting a reference time from the data stream, and adjusting the reference time. . 3. The method according to claim 1, wherein the generating unit uses the first and second information acquired by the acquiring unit, the reference time, and a coefficient corresponding to a reproduction speed to generate first offset information and second information. The recording / reproducing apparatus according to claim 2, wherein offset information is generated. 4. A recording / reproducing method of a recording / reproducing apparatus for recording and reproducing a data stream of an encoded AV signal, comprising: a reading step of reading the data stream from an information recording medium; An obtaining step of obtaining, from the output data stream, first information indicating a decoding timing of the data stream and second information indicating an output timing; and the first and second information obtained in the processing of the obtaining step. Generating the first offset information and the second offset information by offsetting the second information, and generating the first and second information included in the data stream by the processing of the generating step. Said the first
And a replacement step of replacing with the second offset information; and a decoding step of decoding the data stream including the first and second offset information to reproduce a video signal and an audio signal. Recording and playback method. 5. A recording and reproducing program for recording and reproducing a data stream of an encoded AV signal, comprising: a reading step of reading the data stream from an information recording medium; An obtaining step of obtaining, from the output data stream, first information indicating a decoding timing of the data stream and second information indicating an output timing; and the first and second information obtained in the processing of the obtaining step. Generating the first offset information and the second offset information by offsetting the second information, and generating the first and second information included in the data stream by the processing of the generating step. Said the first
And a replacement step of replacing with the second offset information; and a decoding step of decoding the data stream including the first and second offset information to reproduce a video signal and an audio signal. Recording medium on which a computer-readable program to be executed is recorded. 6. A computer for recording and reproducing a data stream of an encoded AV signal, comprising: a read step of reading the data stream from an information recording medium; and the data stream read in the processing of the read step. An obtaining step of obtaining first information indicating a decoding timing of the data stream and second information indicating an output timing of the data stream; and offsetting the first and second information obtained in the processing of the obtaining step. And generating the first offset information and the second offset information; and generating the first and second information included in the data stream by the first and second information generated in the processing of the generating step.
And a replacing step of replacing the data stream with the second offset information, and a decoding step of decoding the data stream including the first and second offset information to reproduce a video signal and an audio signal.