JP2011147057A - Playback apparatus, control method and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a playback apparatus capable of achieving special reproduction such as seeking, reverse-slow and film-frame-back functions while designating a PTS (Presentation Time Stamp). <P>SOLUTION: A playback apparatus (100) includes: an acquisition means (2) for acquiring at least data of a first GOP (Group of Picture) and data of a second GOP just before the first GOP, including data of a designated PTS for outputting image data, when the designated PTS is received; and a control means (43) for decoding the data acquired by the acquisition means (2) to the data of the designated PTS, and outputting image data of the designated PTS. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a technique for reproducing compressed image data of the MPEG (Moving Picture Image Coding Experts Group) method.

  The MPEG method is standardized as a method for encoding compressed image data. In the MPEG image encoding algorithm, encoding is performed in GOP (Group of Picture) units in order to enable a random access function. Each GPO is composed of an I picture, a P picture, and a B picture.

The I picture indicates an intra-coded picture (intra-frame coded picture), is picture data that is intra-frame coded, and is a picture that is not subjected to motion compensation.
A P picture indicates a Predictive-coded picture (forward prediction coded picture), and is a picture that has been subjected to motion compensation from the previous reproduced picture data (I picture or P picture) and subjected to interframe coding. is there.
A B picture indicates a bi-directionally predictive-coded picture (bidirectional predictive-coded picture), and bi-directional prediction is performed by performing motion compensation from the previous and next reproduced image data (I picture or P picture). This is a picture subjected to the inter-frame coding.

  Note that in order to realize frame-by-frame image reproduction in the above-described MPEG encoding encoding apparatus, seek, forward slow, reverse slow, frame advance, and frame return functions are required by user operations. .

  The forward throw and frame advance functions can be implemented using the well-known Direct Show function.

  However, special playback such as seek, reverse throw, and frame return functions cannot be realized using the well-known Direct Show function.

  For this reason, it is necessary to develop a new control method for realizing special reproduction such as seek, reverse throw, and frame return function.

  In addition, as a technical document filed prior to the present invention, there is a document that discloses a method for reproducing MPEG compressed moving image data in the reverse direction (see, for example, Patent Document 1).

  In the above-mentioned patent document 1, MPEG compressed moving image data is input in reverse order to forward playback in GOP units for backward playback. The switching circuits 8, 9, and 5 are controlled to switch the input series, and 1 GOP I picture and P picture, and I picture related to the previous GOP in the forward direction are decoded and reproduced, and stored in the frame memory 2a. On the other hand, a 1 GOP B picture is stored in the data memory 7 as encoded data. The B picture in the data memory 7 is decoded and reproduced while rewriting the data in the memories 7 and 2a by the FIFO method, and the switch circuit 6 is controlled to switch the reproduced image data of each picture in the reverse order. It is decided to make it output.

JP-A-8-102913

  In Patent Document 1, the I picture and the P picture are stored in the frame memory 2a, the B picture is stored in the data memory 7, and the reproduced image data of each picture is rewritten while the data in each of the memories 7 and 2a is rewritten by the FIFO method. It is disclosed that the signals are continuously output in the reverse direction.

  However, the above-mentioned patent document 1 does not describe anything about realizing special reproduction such as seek, reverse direction throw, and frame return function by specifying PTS.

  The present invention has been made in view of the above circumstances, and provides a playback apparatus, a control method, and a program capable of specifying special PTS and realizing special playback such as seek, reverse throw, and frame rewind function. For the purpose.

  In order to achieve this object, the present invention has the following features.

<Reproducing device>
The playback apparatus according to the present invention is
When a designated PTS (Presentation Time Stamp) for outputting image data is received, a first GOP (Group of Picture) including the data of the designated PTS and a second immediately before the first GOP An acquisition means for acquiring at least GOP data;
Control means for decoding the data acquired by the acquisition means up to the data of the designated PTS, and outputting the image data of the designated PTS;
It is characterized by having.

<Control method>
The control method according to the present invention includes:
A control method performed by a playback device,
When a designated PTS (Presentation Time Stamp) for outputting image data is received, a first GOP (Group of Picture) including the data of the designated PTS and a second immediately before the first GOP An acquisition process for acquiring at least GOP data;
Decoding the data acquired in the acquisition step up to the data of the designated PTS, and outputting the image data of the designated PTS;
It is characterized by having.

<Program>
The program according to the present invention is:
When a designated PTS (Presentation Time Stamp) for outputting image data is received, a first GOP (Group of Picture) including the data of the designated PTS and a second immediately before the first GOP An acquisition process that acquires at least GOP data;
Decoding the data acquired in the acquisition process up to the data of the designated PTS, and outputting the image data of the designated PTS;
Is executed by a computer.

  According to the present invention, it is possible to realize special reproduction such as seek, reverse direction throw, and frame rewind function by specifying PTS.

1 is a diagram illustrating an example of an internal configuration of a playback device 100 according to a first embodiment. It is a figure which shows the processing operation example of the reproducing | regenerating apparatus 100 of 1st Embodiment. It is a figure which shows the specific example for demonstrating the processing operation example of the reproducing | regenerating apparatus 100 of 1st Embodiment. It is a figure which shows the example of an internal structure of the reproducing | regenerating apparatus 100 of 2nd Embodiment. It is a figure which shows the processing operation example of the reproducing | regenerating apparatus 100 of 2nd Embodiment. It is a figure which shows the specific example for demonstrating the processing operation example of the reproducing | regenerating apparatus 100 of 2nd Embodiment. It is a figure which shows the specific example for demonstrating the processing operation example of the reproducing | regenerating apparatus 100 of 2nd Embodiment. It is a figure which shows the specific example for demonstrating the processing operation example of the reproducing | regenerating apparatus 100 of 2nd Embodiment. FIG. 3 is a diagram illustrating an internal configuration example of a Video Decoder 43 configuring the playback device 100 of the present embodiment. It is a figure which shows the processing operation example of Video Decoder43.

<Outline of playback device 100>
First, an overview of the playback apparatus 100 of the present embodiment will be described with reference to FIGS. 1 and 4.

  As shown in FIG. 1, the playback apparatus 100 according to the present embodiment, when receiving a designated PTS (Presentation Time Stamp) for outputting image data, receives a first GOP (Group of) including data of the designated PTS. Picture) and acquisition means (corresponding to the file reader 2) that acquires at least the data of the second GOP immediately before the first GOP, and the data acquired by the acquisition means (2) is decoded to the data of the specified PTS And control means (corresponding to Video Decoder 43) for outputting the image data of the designated PTS. As a result, the playback apparatus 100 according to the present embodiment can implement special playback such as seek, reverse throw, and frame return function by specifying PTS.

  Further, as shown in FIG. 4, the playback apparatus 100 of the present embodiment is a buffer (corresponding to the internal buffer 438) that stores image data of decoded I (Intra-coded) pictures and P (Predictive-coded) pictures. The control means (43) outputs the image data of the designated PTS using the decoded I picture and P picture image data stored in the buffer (438). As a result, the playback apparatus 100 according to the present embodiment outputs the image data of the designated PTS using the decoded I picture and P picture image data stored in the buffer (438). The processing time until the image data is output can be shortened. Hereinafter, the playback apparatus 100 of the present embodiment will be described in detail with reference to the accompanying drawings.

(First embodiment)
<Internal configuration example of playback device 100>
First, an example of the internal configuration of the playback apparatus 100 of this embodiment will be described with reference to FIG.

  The playback device 100 of this embodiment includes a memory 1, a file reader 2, a Demux 3, a Decoder 4, a Video Render 5, an Audio Render 6, a display 7, and a speaker 8.

  The memory 1 stores various information, and stores, for example, MPEG data such as a recorded program.

  The file reader 2 performs a function of reading MPEG data. When the file reader 2 receives a designated PTS of image data to be displayed on the display 7, the file reader 2 reads MPEG data corresponding to the designated PTS from the memory 1. The file reader 2 of this embodiment reads from the memory 1 in order from the MPEG data of the GOP immediately before the GOP including the designated PTS. The file reader 2 outputs the MPEG data read sequentially from the memory 1 to the Demux 3 together with the designated PTS.

  Demux3 performs a function of separating MPEG data into Video code data and Audio code data. The Demux 3 separates the MPEG data received from the file reader 2 into Video code data and Audio code data, and outputs a designated PTS to the Decoder 4 together with the separated Video code data and Audio code data.

  Decoder 4 performs a function of converting MPEG data into output data. Decoder 4 includes Buffers 41 and 42, and stores Video code data and Audio code data received from Demux 3 in Buffers 41 and 42, respectively. The Video Decoder 43 decodes the video code data stored in the Buffer 41 based on the designated PTS received from the Demux 3. The Audio Decoder 44 decodes the Audio code data stored in the Buffer 42 based on the designated PTS received from the Demux 3. However, the Audio Decoder 44 may not decode the Audio code data depending on the situation.

  Video Render5 performs a function of outputting image data. The Video Render 5 outputs the image data decoded by the Video Decoder 43 to the display 7 and displays the image data on the display 7.

  Audio Render 6 performs a function of outputting audio data. The Audio Render 6 outputs the audio data decoded by the Audio Decoder 44 to the speaker 8 and outputs the audio data from the speaker 8. However, Audio Render 6 may not output audio data depending on the situation.

<Example of processing operation of playback device 100>
Next, an example of the processing operation of the playback apparatus 100 of this embodiment will be described with reference to FIG. The following processing operation example is a case where seek, backward throw, and frame return are performed. Seek, reverse throw, and frame return can be realized by repeating the following processing operations shown in FIG.

  In the playback device 100 of the present embodiment, when seek, backward slow, and frame return are started, image data to be displayed on the display 7 at the start of playback of seek, backward slow, and frame backward is specified by a user operation as PTS (Presentation Time (Step A1).

  When the PTS of the image data to be displayed on the display 7 is designated (Step A1 / Yes), the playback device 100 uses the designated PTS to make the file reader 2 the previous GOP including the designated PTS. Read from memory 1 in order from MPEG data of GOP. Then, the designated PTS is output to the Demux 3 together with the MPEG data read sequentially from the memory 1.

  Demux3, when receiving MPEG data from the file reader 2, separates the received MPEG data into Video code data and Audio code data, and outputs the specified PTS together with the separated Video code data and Audio code data to Decoder4 To do.

  As a result, when the PTS is designated (step A1 / Yes), the playback apparatus 100 sequentially adds MPEG data (Video code data and Audio code data) of the GOP immediately preceding the GOP including the designated PTS to the Decoder 4 It can be entered (step A2).

  Decoder 4 stores Video code data and Audio code data received from Demux 3 in Buffers 41 and 42.

  The Video Decoder 43 decodes the video code data of the I, P, and B pictures stored in the Buffer 41 to the designated PTS based on the designated PTS received from the Demux 3 (Step A3).

  The Audio Decoder 44 decodes the audio code data stored in the Buffer 42 based on the designated PTS received from the Demux 3. However, the Audio Decoder 44 may not decode the Audio code data depending on the situation.

  Video Render 5 outputs the image data decoded by Decoder 4 to display 7 and displays the image data on display 7. Thereby, Video Render 5 can display the image data of the designated PTS on the display 7 (step A4).

  The Audio Render 6 outputs the audio data decoded by the Audio Decoder 44 to the speaker 8 and outputs the audio data from the speaker 8. However, Audio Render 6 may not output audio data depending on the situation.

<Specific example of the above processing operation>
Next, a specific example of the processing operation shown in FIG. 2 will be described with reference to FIG. In the following processing operation, a case where playback of seek, reverse direction slowdown and frame return is started from “B24” will be described. In this embodiment, for simplification of description, a 1 GOP unit is composed of 9 frames, but normally, a 1 GOP unit is composed of the number of frames conforming to MPEG. Also, the numbers given to the symbols (I, P, B) indicating each picture are for dividing each picture, and the data before being input to the Decoder 4 is indicated by “code order” shown in FIG. The data configured in the order and decoded by the Decoder 4 is configured in the order indicated by “display order” shown in FIG. For example, “GOP1” is composed of “I01 → B02 → B03 → P04 → B05 → B06 → P07 → B08 → B09” before being input to Decoder4. After decoding with Decoder4, “B02 → B03 → I01 → B05 → B06 → P04 → B08 → B09 → P07 ”. In addition, since the decoding performed by Decoder 4 is a process compliant with MPEG, specific processing is omitted.

  When the PTS of “B24” to be displayed on the display 7 at the start of playback of seek, reverse slow-down, and frame return is specified by the user operation (step A1 / Yes), the playback device 100 determines that the file reader 2 Based on the designated PTS of “B24”, the MPEG data of GOP2 immediately preceding GOP3 including the designated PTS of “B24” is read from the memory 1 in order. Then, the designated PTS is output to the Demux 3 together with the MPEG data read sequentially from the memory 1.

  Demux3, when receiving MPEG data from the file reader 2, separates the received MPEG data into Video code data and Audio code data, and outputs the specified PTS together with the separated Video code data and Audio code data to Decoder4 To do.

  As a result, when the “B24” PTS is designated (step A1 / Yes), the playback device 100 allows the GOP2 MPEG data (Video code data and the video data immediately before GOP3 including the designated “B24” PTS to be included). Audio code data) can be input to Decoder 4 in order (step A2).

  Decoder 4 stores Video code data and Audio code data received from Demux 3 in Buffers 41 and 42. The Video Decoder 43 decodes the video code data of the I, P, and B pictures stored in the Buffer 41 based on the designated PTS of “B24” received from the Demux 3. At this time, the Video Decoder 43 decodes from the head data (I10) of the 2GOP, and decodes up to “B24” data of the designated PTS (up to I10 to B24 data) (step A3).

  Thereby, the Video Render 5 can display the image data of “B24” of the designated PTS decoded by the Video Decoder 43 on the display 7 (Step A4).

  The playback device 100 can achieve seek, reverse slow, and frame reverse playback by repeating the above processing operations.

<Operation / Effect of Playback Device 100 of this Embodiment>
As described above, when receiving a designated PTS (Presentation Time Stamp) for outputting image data, the playback apparatus 100 according to the present embodiment receives a first GOP (Group of Picture) including data of the designated PTS and At least the data of the second GOP immediately before the first GOP is acquired. Then, the acquired data is decoded up to the data of the designated PTS, and the image data of the designated PTS is output. As a result, the playback apparatus 100 according to the present embodiment can implement special playback such as seek, reverse throw, and frame return function by specifying PTS.

(Second Embodiment)
Next, a second embodiment will be described.

  The playback apparatus 100 according to the first embodiment repeats the processing operation illustrated in FIG. 2 to realize seek, reverse slow, and frame reverse playback.

  However, if the processing operation shown in FIG. 2 is repeated, the data from the top 2GOP data to the designated PTS data will be decoded many times, so the process until the designated PTS image data is displayed on the display 7 The time will be longer.

  As shown in FIG. 4, the playback apparatus 100 according to the second embodiment includes a buffer 438 for storing image data of decoded I (Intra-coded) pictures and P (Predictive-coded) pictures. Using the decoded I picture and P picture image data stored in the buffer 438, the image data of the designated PTS is output. As a result, the playback device 100 according to the present embodiment outputs the image data of the designated PTS using the decoded I picture and P picture image data stored in the buffer 438, so that the image of the designated PTS is output. Processing time until data is output can be shortened. Hereinafter, the second embodiment will be described with reference to FIGS.

<Internal configuration example of playback device 100>
First, an example of the internal configuration of the playback apparatus 100 of this embodiment will be described with reference to FIG.

  Similar to the first embodiment, the playback device 100 of the present embodiment includes a memory 1, a file reader 2, a Demux 3, a Decoder 4, a Video Render 5, an Audio Render 6, a display 7, and a speaker 8. Including. Since the function of each part is the same as in the first embodiment, a specific description is omitted.

  Note that the Video Decoder 43 of this embodiment has internal buffers 437 and 438, and stores the image data decoded by the Video Decoder 43 in the internal buffers 437 and 438. The internal buffers 437 and 438 are an internal buffer 437 dedicated to the B picture that stores the image data of the B picture decoded by the Video Decoder 43, and an internal buffer dedicated to the I and P picture that stores the image data of the I and P pictures decoded by the Video Decoder 43. 438. The internal buffer 438 dedicated to I and P pictures stores I and P picture image data and PTS values in association with each other. The data capacity of the internal buffers 437 and 438 is not particularly limited, and can be appropriately designed to store an arbitrary frame. However, in order to implement the present invention, the internal buffer 437 dedicated to B pictures is configured with a data capacity capable of storing at least one frame of image data, and the internal buffer 438 dedicated to I and P pictures is at least It is preferable to configure with a data capacity capable of storing image data for I and P picture frames included in 2 GOP.

<First Processing Operation Example of Playback Device 100>
Next, a first processing operation example of the playback apparatus 100 of the present embodiment will be described with reference to FIG. The following first processing operation example is a case where frame rewinding is performed after normal playback.

  When normal playback is performed in the playback device 100 of the present embodiment, I / P picture data for 2 GOP decoded by the Video Decoder 43 during normal playback is stored in the internal buffer 438 dedicated to the I and P pictures. Become. Further, the B-picture image data for one frame decoded by the video decoder 43 during normal reproduction is stored in the internal buffer 437 dedicated to the B picture.

  In addition, when frame return is started after normal playback is performed in the playback device 100 of the present embodiment, image data to be displayed on the display 7 at the start of frame return is designated by PTS by a user operation (step B1).

  When the PTS is designated (step B1 / Yes), the playback device 100, based on the designated PTS, the memory 1 in order from the MPEG data of the GOP immediately preceding the GOP including the designated PTS. Read from. Then, the designated PTS is output to the Demux 3 together with the MPEG data read sequentially from the memory 1.

  Demux3, when receiving MPEG data from the file reader 2, separates the received MPEG data into Video code data and Audio code data, and outputs the specified PTS together with the separated Video code data and Audio code data to Decoder4 To do.

  As a result, when the PTS is designated (step B1 / Yes), the playback apparatus 100 sequentially adds MPEG data (Video code data and Audio code data) of the GOP immediately preceding the GOP including the designated PTS to the Decoder 4. It can be entered (step B2).

  Decoder 4 stores Video code data and Audio code data received from Demux 3 in Buffers 41 and 42.

  The Video Decoder 43 decodes the video code data of the I, P, and B pictures stored in the Buffer 41 based on the designated PTS received from the Demux 3. At this time, the Video Decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, decodes only the video code data of the I and P pictures not stored in the internal buffer 438 to the specified PTS, and associates them with the PTS value. Store in the internal buffer 438. In addition, when the designated PTS is a B picture, the Video Decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures and decodes the B picture data using the I and P pictures stored in the internal buffer 438. And stored in the internal buffer 437 dedicated to B pictures (step B3).

  As a result, the video decoder 43 does not decode the video code data of the I and P pictures stored in the internal buffer 438 at the start of frame return, and does not decode the I and P pictures stored in the internal buffer 438 at the start of frame return. Only the video code data and the video code data of the B picture of the designated PTS designated at the start of frame return can be decoded. If the designated PTS specified at the start of frame return is an I or P picture, if the I and P pictures of the designated PTS have already been stored in the internal buffer 438, the decoding process is not performed and the I and P pictures are not stored in the internal buffer 438. In the case of storage, decoding processing is performed.

  The Audio Decoder 44 decodes the Audio code data stored in the Buffer 42 based on the designated PTS received from the Demux 3. However, the Audio Decoder 44 may not decode the Audio code data depending on the situation.

  The Video Render 5 outputs the image data stored in the internal buffers 437 and 438 to the display 7 and displays the image data on the display 7. Thereby, Video Render 5 can display the image data of the designated PTS on the display 7 (step B4).

  The Audio Render 6 outputs the audio data decoded by the Audio Decoder 44 to the speaker 8 and outputs the audio data from the speaker 8. However, Audio Render 6 may not output audio data depending on the situation.

<Specific example of first processing operation>
Next, a specific example of the first processing operation described above will be described with reference to FIG. In the following processing operation, a case where normal reproduction is performed up to “B24” shown in FIG. 6 and then one frame return and two frame return are performed will be described.

  In the playback apparatus 100 of this embodiment, when normal playback is performed up to “B24” shown in FIG. 6A, normal playback is performed up to “B24” in the order of GOP1, GOP2, and GOP3. Therefore, the video decoder 43 decodes from the beginning of GOP1 to “B24” of GOP3 (from I01 to B24), and the video renderer 5 displays “B24” decoded by the video decoder 43 on the display 7.

  The Video Decoder 43 stores I / P picture data (P07, I10, P13, P16, I19, P22) for 2 GOPs decoded to “B24” in the internal buffer 438 dedicated to the I and P pictures. Become. Further, the B picture data (B24) for one frame is stored in the internal buffer 437 dedicated to the B picture. Then, the Video Render 5 displays “B24” stored in the internal buffer 437 dedicated to the B picture on the display 7.

  In addition, when the normal playback shown in FIG. 6 (a) is performed in the playback apparatus 100 of the present embodiment and the single frame return shown in FIG. The image data (B23) to be displayed on is designated by PTS (step B1).

  When the PTS of “B23” is designated (step B1 / Yes), the playback device 100 uses the GOP3 including the designated PTS of “B23” based on the designated PTS of “B23”. Read from the memory 1 in order from the previous GOP2 MPEG data. Then, the designated PTS is output to the Demux 3 together with the MPEG data read sequentially from the memory 1.

  Demux3, when receiving MPEG data from the file reader 2, separates the received MPEG data into Video code data and Audio code data, and outputs the specified PTS together with the separated Video code data and Audio code data to Decoder4 To do.

  As a result, when the “B23” PTS is designated (step B1 / Yes), the playback device 100 allows the GOP2 MPEG data (Video code data and the video data immediately before GOP3 including the designated “B23” PTS to be included). Audio code data) can be input to Decoder 4 in order (step B2).

  Decoder 4 stores Video code data and Audio code data received from Demux 3 in Buffers 41 and 42.

  The Video Decoder 43 decodes the video code data of the I, P, and B pictures stored in the Buffer 41 based on the designated PTS “B23” received from the Demux 3. At this time, the video decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, and designates only the video code data of the I and P pictures included in the GOP2 and GOP3 that are not stored in the internal buffer 438 by specifying “B23”. The PTS is decoded and stored in the internal buffer 438 in association with the PTS value. However, since the I and P pictures (I10, P13, P16, I19, and P22) up to the designated PTS of “B23” are already stored in the internal buffer 438, the decoding process of the video code data of the I and P pictures is not I will not do it.

  Since the designated PTS is a B picture of “B23”, the Video Decoder 43 refers to I19 and P22 stored in the internal buffer 438, decodes the video code data of “B23”, and decodes the decoded “B23” Are stored in an internal buffer 347 dedicated to B pictures (step B3).

  As a result, the video decoder 43 does not perform the decoding process on the video code data (I10, P13, P16, I19, P22) of the I and P pictures stored in the internal buffer 438 at the start of returning one frame, and starts returning one frame. Only the video code data of the B picture of “B23” of the designated PTS designated at the time can be decoded.

  The Video Render 5 can display the image data of “B23” of the designated PTS decoded by the Video Decoder 43 on the display 7 (Step B4).

  When performing the two-frame return shown in FIG. 6C, the image data (B21) to be displayed on the display 7 at the start of the two-frame return is designated by the PTS by the user operation (step B1).

  When the PTS of “B21” is designated (step B1 / Yes), the playback device 100 uses the GOP3 including the designated PTS of “B21” based on the designated PTS of “B21”. Read from the memory 1 in order from the previous GOP2 MPEG data. Then, the designated PTS is output to the Demux 3 together with the MPEG data read sequentially from the memory 1.

  Demux3, when receiving MPEG data from the file reader 2, separates the received MPEG data into Video code data and Audio code data, and outputs the specified PTS together with the separated Video code data and Audio code data to Decoder4 To do.

  As a result, when the “B21” PTS is designated (step B1 / Yes), the playback device 100 allows the GOP2 MPEG data immediately before GOP3 including the designated “B21” PTS (Video code data and Audio code data) can be input to Decoder 4 in order (step B2).

  Decoder 4 stores Video code data and Audio code data received from Demux 3 in Buffers 41 and 42.

  The Video Decoder 43 decodes the video code data of the I, P, and B pictures stored in the Buffer 41 based on the designated PTS “B21” received from the Demux 3. At this time, the Video Decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, and designates only the video code data of the I and P pictures included in the GOP2 and GOP3 that are not stored in the internal buffer 438 as “B21”. The PTS is decoded and stored in the internal buffer 438 in association with the PTS value. However, since the I and P pictures (I10, P13, P16, and I19) up to the designated PTS of “B21” have already been stored in the internal buffer 438, the video code data of the I and P pictures is not decoded. It will be.

  Since the designated PTS is a B picture of “B21”, the Video Decoder 43 refers to P16 and I19 stored in the internal buffer 438, decodes the video code data of “B21”, and decodes the decoded “B21”. Are stored in an internal buffer 347 dedicated to B pictures (step B3).

  As a result, the Video Decoder 43 does not decode the I / P picture video code data (I10, P13, P16, I19) stored in the internal buffer 438 at the start of the two-frame return, and is designated at the start of the two-frame return. Only the video code data of the B picture of “B21” of the designated PTS can be decoded.

  The Video Render 5 can display the image data of “B21” of the designated PTS decoded by the Video Decoder 43 on the display 7 (Step B4).

  As a result, the playback device 100 according to the present embodiment, when performing normal playback and receiving a designated PTS for starting frame rewinding, has decoded I and P pictures stored in the internal buffer 438 during normal playback. Frame-by-frame playback can be performed using this image data. For this reason, it is possible to shorten the processing time until the image data of the designated PTS designated at the start of frame return is output.

<Second Processing Operation Example of Playback Device 100>
Next, a second processing operation example of the playback apparatus 100 of this embodiment will be described with reference to FIG. The following second processing operation example is a case where reverse slow playback is performed after seek playback is performed.

  When seek playback is performed in the playback apparatus 100 of the present embodiment, image data to be displayed on the display 7 at the time of seek playback is specified by PTS by a user operation (step B1).

  When the PTS is designated (step B1 / Yes), the playback device 100, based on the designated PTS, the memory 1 in order from the MPEG data of the GOP immediately preceding the GOP including the designated PTS. Read from. Then, the designated PTS is output to the Demux 3 together with the MPEG data read sequentially from the memory 1.

  Demux3, when receiving MPEG data from the file reader 2, separates the received MPEG data into Video code data and Audio code data, and outputs the specified PTS together with the separated Video code data and Audio code data to Decoder4 To do.

  As a result, when the PTS is designated (step B1 / Yes), the playback apparatus 100 sequentially adds MPEG data (Video code data and Audio code data) of the GOP immediately preceding the GOP including the designated PTS to the Decoder 4. It can be entered (step B2).

  Decoder 4 stores Video code data and Audio code data received from Demux 3 in Buffers 41 and 42.

  The Video Decoder 43 decodes the video code data of the I, P, and B pictures stored in the Buffer 41 based on the designated PTS received from the Demux 3. At this time, the Video Decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, decodes only the video code data of the I and P pictures not stored in the internal buffer 438 to the specified PTS, and associates them with the PTS value. Store in the internal buffer 438. In addition, when the designated PTS is a B picture, the Video Decoder 43 refers to the internal buffer 438 dedicated to I and P pictures, decodes the data of the B picture, and stores it in the internal buffer 437 dedicated to the B picture (step B3 ).

  As a result, the Video Decoder 43 can decode only the video code data of the I and P pictures that are not stored in the internal buffer 438 at the start of seek playback, and the video code data of the B picture of the designated PTS specified at the start of seek playback. it can. If the specified PTS specified at the start of seek playback is an I or P picture, if the I and P pictures of the specified PTS are already stored in the internal buffer 438, the decoding process is not performed and the I and P pictures are not stored in the internal buffer 438. In the case of storage, decoding processing is performed.

  The Audio Decoder 44 decodes the Audio code data stored in the Buffer 42 based on the designated PTS received from the Demux 3. However, the Audio Decoder 44 may not decode the Audio code data depending on the situation.

  The Video Render 5 outputs the image data stored in the internal buffers 437 and 438 to the display 7 and displays the image data on the display 7. Thereby, Video Render 5 can display the image data of the designated PTS on the display 7 (step B4).

  The Audio Render 6 outputs the audio data decoded by the Audio Decoder 44 to the speaker 8 and outputs the audio data from the speaker 8. However, Audio Render 6 may not output audio data depending on the situation.

  In addition, when performing reverse slow playback after performing seek playback in the playback device 100 of the present embodiment, image data to be displayed on the display 7 at the start of reverse slow playback is specified by PTS by a user operation (step B1). .

  When the PTS is designated (step B1 / Yes), the playback device 100, based on the designated PTS, the memory 1 in order from the MPEG data of the GOP immediately preceding the GOP including the designated PTS. Read from. Then, the designated PTS is output to the Demux 3 together with the MPEG data read sequentially from the memory 1.

  Demux3, when receiving MPEG data from the file reader 2, separates the received MPEG data into Video code data and Audio code data, and outputs the specified PTS together with the separated Video code data and Audio code data to Decoder4 To do.

  As a result, when the PTS is designated (step B1 / Yes), the playback apparatus 100 sequentially adds MPEG data (Video code data and Audio code data) of the GOP immediately preceding the GOP including the designated PTS to the Decoder 4. It can be entered (step B2).

  Decoder 4 stores Video code data and Audio code data received from Demux 3 in Buffers 41 and 42.

  The Video Decoder 43 decodes the video code data of the I, P, and B pictures stored in the Buffer 41 based on the designated PTS received from the Demux 3. At this time, the Video Decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, decodes only the video code data of the I and P pictures not stored in the internal buffer 438 to the specified PTS, and associates them with the PTS value. Store in the internal buffer 438. In addition, when the designated PTS is a B picture, the Video Decoder 43 refers to the internal buffer 438 dedicated to I and P pictures, decodes the data of the B picture, and stores it in the internal buffer 437 dedicated to the B picture (step B3 ).

  As a result, the video decoder 43 decodes only the video code data of the I and P pictures that are not stored in the internal buffer 438 at the start of reverse slow play, and the video code data of the B picture of the designated PTS specified at the start of reverse slow play. be able to. If the designated PTS specified at the start of reverse slow playback is I or P picture, if the I and P pictures of the designated PTS are already stored in the internal buffer 438, the decoding process is not performed and the internal buffer 438 When the data is not stored, the decoding process is performed.

  The Audio Decoder 44 decodes the Audio code data stored in the Buffer 42 based on the designated PTS received from the Demux 3. However, the Audio Decoder 44 may not decode the Audio code data depending on the situation.

  The Video Render 5 outputs the image data stored in the internal buffers 437 and 438 to the display 7 and displays the image data on the display 7. Thereby, Video Render 5 can display the image data of the designated PTS on the display 7 (step B4).

  The Audio Render 6 outputs the audio data decoded by the Audio Decoder 44 to the speaker 8 and outputs the audio data from the speaker 8. However, Audio Render 6 may not output audio data depending on the situation.

<Specific Example of Second Processing Operation>
Next, a specific example of the above-described second processing operation will be described with reference to FIGS. In the following processing operation, a case where seek reproduction is started at “B24” shown in FIG. 7 and then reverse slow reproduction is performed will be described.

  In the playback apparatus 100 of the present embodiment, as shown in FIG. 7A, when the seek playback is started at “B24”, the image data (B24) to be displayed on the display 7 when the seek playback is started by the user operation. Specify with PTS (step B1).

  When the PTS of “B24” is designated (step B1 / Yes), the playback device 100 uses the GOP3 including the designated PTS of “B24” based on the designated PTS of “B24”. Read from the memory 1 in order from the previous GOP2 MPEG data. Then, the designated PTS is output to the Demux 3 together with the MPEG data read sequentially from the memory 1.

  Demux3, when receiving MPEG data from the file reader 2, separates the received MPEG data into Video code data and Audio code data, and outputs the specified PTS together with the separated Video code data and Audio code data to Decoder4 To do.

  As a result, when the “B24” PTS is designated (step B1 / Yes), the playback device 100 allows the GOP2 MPEG data (Video code data and the video data immediately before GOP3 including the designated “B24” PTS to be included). Audio code data) can be input to Decoder 4 in order (step B2).

  Decoder 4 stores Video code data and Audio code data received from Demux 3 in Buffers 41 and 42.

  The video decoder 43 decodes the video code data of the I, P, and B pictures stored in the buffer 41 up to the designated PTS of “B24” based on the designated PTS of “B24” received from the Demux 3. At this time, the Video Decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, and designates only the video code data of the I and P pictures included in the GOP2 and GOP3 that are not stored in the internal buffer 438 as “B24”. The PTS is decoded and stored in the internal buffer 438 in association with the PTS value.

  Since no data is stored in the internal buffer 438 at the start of seek reproduction shown in FIG. 7A, the Video Decoder 43 performs I, P pictures (I10, P13, P16) up to the designated PTS of “B24”. , I19, P22) are decoded and stored in the internal buffer 438. Since the designated PTS is a B picture of “B24”, the Video Decoder 43 refers to I19 and P22 stored in the internal buffer 438, decodes the video code data of “B24”, and decodes the decoded “B24” Data is stored in an internal buffer 347 dedicated to B pictures (step B3).

  As a result, the video decoder 43 receives the I / P picture video code data (I10, P13, P16, I19, P22) that is not stored in the internal buffer 438 at the start of seek playback, and the specified PTS specified at the start of seek playback. Only the video code data of the B picture of B24 can be decoded.

  The Video Render 5 can display the image data of “B24” of the designated PTS decoded by the Video Decoder 43 on the display 7 (Step B4).

  In addition, in the playback apparatus 100 of the present embodiment, when the reverse slow playback shown in FIG. 7B is started after the seek playback is started at “B24” shown in FIG. The image data (B23) to be displayed on the display 7 at the start of reproduction is designated by PTS (step B1).

  When the PTS of “B23” is designated (step B1 / Yes), the playback device 100 inputs the data from GOP2 immediately before GOP3 including the designated PTS of “B23” to Decoder 4 in order (step B2). ).

  Decoder 4 decodes the video code data of the input GOP I and P pictures up to the designated PTS of “B23”. At this time, the video decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, and designates only the video code data of the I and P pictures included in the GOP2 and GOP3 that are not stored in the internal buffer 438 by specifying “B23”. The PTS is decoded and stored in the internal buffer 438 in association with the PTS value. However, since the I and P pictures (I10, P13, P16, I19, and P22) up to the designated PTS of “B23” are already stored in the internal buffer 438, the decoding process of the video code data of the I and P pictures is not I will not do it.

  Since the designated PTS is a B picture of “B23”, the Video Decoder 43 refers to I19 and P22 stored in the internal buffer 438, decodes the video code data of “B23”, and decodes the decoded “B23” Are stored in an internal buffer 347 dedicated to B pictures (step B3).

  Then, the Video Render 5 displays the image data “B23” of the designated PTS decoded by the Video Decoder 43 on the display 7 (Step B4).

  Next, when the “I19” PTS shown in FIG. 7C is designated (step B1 / Yes), the playback device 100 sets the GOP2 immediately preceding GOP3 including the designated “I19” PTS. Data is input to Decoder 4 in order (step B2).

  Decoder 4 decodes the video code data of the input GOP I and P pictures up to the designated PTS of “I19”. At this time, the video decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, and designates only the video code data of the I and P pictures included in the GOP2 and GOP3 that are not stored in the internal buffer 438 by specifying “I19”. The PTS is decoded and stored in the internal buffer 438 in association with the PTS value. However, since the I and P pictures (I10, P13, P16, and I19) up to the designated PTS of “I19” are already stored in the internal buffer 438, the video code data of the I and P pictures is not decoded. It will be.

  Also, since the I picture of “I19” of the designated PTS has already been stored in the internal buffer 438, the decoding process of the video code data of the “I19” picture of the designated PTS is not performed. Then, Video Render5 displays the image data of “I19” of the designated PTS stored in the internal buffer 438 on the display 7 (step B4).

  Next, when the “B21” PTS shown in FIG. 8D is designated (step B1 / Yes), the playback device 100 sets the GOP2 immediately preceding GOP3 including the designated PTS of “B21”. Data is input to Decoder 4 in order (step B2).

  Decoder 4 decodes the video code data of the input GOP I and P pictures up to the designated PTS of “B21”. At this time, the Video Decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, and designates only the video code data of the I and P pictures included in the GOP2 and GOP3 that are not stored in the internal buffer 438 as “B21”. The PTS is decoded and stored in the internal buffer 438 in association with the PTS value. However, since the I and P pictures (I10, P13, P16, and I19) up to the designated PTS of “B21” have already been stored in the internal buffer 438, the video code data of the I and P pictures is not decoded. It will be.

  Since the designated PTS is a B picture of “B21”, the Video Decoder 43 refers to P16 and I19 stored in the internal buffer 438, decodes the video code data of “B21”, and decodes the decoded “B21”. Are stored in an internal buffer 347 dedicated to B pictures (step B3).

  Then, the Video Render 5 displays the image data “B21” of the designated PTS decoded by the Video Decoder 43 on the display 7 (Step B4).

  Next, when the PTS of “B20” shown in FIG. 8E is designated (step B1 / Yes), the playback device 100 sets the GOP2 immediately preceding GOP3 including the designated PTS of “B20”. Data is input to Decoder 4 in order (step B2).

  Decoder 4 decodes the video code data of the input GOP I and P pictures up to the designated PTS of “B20”. At this time, the video decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, and designates only the video code data of the I and P pictures included in the GOP2 and GOP3 that are not stored in the internal buffer 438 as “B20”. The PTS is decoded and stored in the internal buffer 438 in association with the PTS value. However, since the I and P pictures (I10, P13, P16, and I19) up to the designated PTS of “B20” are already stored in the internal buffer 438, the decoding process of the video code data of the I and P pictures is not performed. It will be.

  Since the designated PTS is a B picture of “B20”, the Video Decoder 43 refers to P16 and I19 stored in the internal buffer 438, decodes the video code data of “B20”, and decodes the decoded “B20”. Are stored in an internal buffer 347 dedicated to B pictures (step B3).

  Then, the Video Render 5 displays the image data of “B20” of the designated PTS decoded by the Video Decoder 43 on the display 7 (Step B4).

  Next, when the “P16” PTS shown in FIG. 8F is designated (step B1 / Yes), the playback device 100 determines the GOP1 immediately before GOP2 including the designated “P16” PTS. Data is input to Decoder 4 in order (step B2).

  Decoder 4 decodes the video code data of the input GOP I and P pictures up to the designated PTS of “P16”. At this time, the video decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, and designates only the video code data of the I and P pictures included in the GOP1 and GOP2 not stored in the internal buffer 438 as “P16”. The PTS is decoded and stored in the internal buffer 438 in association with the PTS value. In this case, since the pictures I01, P04, and P07 included in GOP1 are not stored in the internal buffer 438, the pictures I01, P04, and P07 are decoded and stored in the internal buffer 438. However, since the I and P pictures (I10, P13, and P16) up to “P16” of the designated PTS after that are already stored in the internal buffer 438, the decoding process of the video code data of the I and P pictures is performed. There will be no.

  Further, since the P picture of “P16” of the designated PTS has already been stored in the internal buffer 438, the decoding process of the video code data of the picture of “P16” of the designated PTS is not performed. Then, the Video Render 5 displays the image data of “P16” of the designated PTS stored in the internal buffer 438 on the display 7 (step B4).

  Next, when the “B18” PTS shown in FIG. 8G is designated (step B1 / Yes), the playback device 100 determines the GOP1 immediately before GOP2 including the designated “B18” PTS. Data is input to Decoder 4 in order (step B2).

  Decoder 4 decodes the video code data of the input GOP I and P pictures up to the designated PTS of “B18”. At this time, the video decoder 43 refers to the internal buffer 438 dedicated to the I and P pictures, and designates only the video code data of the I and P pictures included in the GOP1 and GOP2 not stored in the internal buffer 438 as “B18”. The PTS is decoded and stored in the internal buffer 438 in association with the PTS value. However, since the I and P pictures (I01, P04, P07, I10, P13, and P16) up to the designated PTS of “B18” are already stored in the internal buffer 438, decoding of the video code data of the I and P pictures No processing will be performed.

  Also, since the designated PTS is a B picture of “B18”, the Video Decoder 43 refers to P13 and P16 stored in the internal buffer 438, decodes the video code data of “B18”, and decodes the decoded “B18” Are stored in an internal buffer 347 dedicated to B pictures (step B3).

  Then, the Video Render 5 displays the image data “B18” of the designated PTS decoded by the Video Decoder 43 on the display 7 (Step B4).

  As a result, when the playback device 100 of the present embodiment receives a designated PTS for starting reverse slow playback after performing seek playback, the decoded I, P stored in the internal buffer 438 during seek playback is received. Reverse slow playback can be performed using picture data. For this reason, it is possible to shorten the processing time until the image data of the designated PTS designated at the start of reverse slow playback is output.

<Internal configuration example of Video Decoder 43>
Next, an internal configuration example of the Video Decoder 43, which is a characteristic part of the present embodiment, will be described with reference to FIG. In the following description, only the functional operation when PTS is specified will be described.

  The video decoder 43 of the present embodiment includes a first PTS check unit 431, a second PTS check unit 432, a decode processing unit 433, a frame memory processing unit 434, and a third PTS check unit 435. And configure.

  The decoding processing unit 433 includes a motion compensation processing unit 436. Motion compensation performed by the motion compensation processing unit 436 performs well-known motion compensation based on MPEG.

  The frame memory processing unit 434 includes internal buffers 437 and 438. The internal buffers 437 and 438 include an internal buffer 437 dedicated to B pictures and an internal buffer 438 dedicated to I and P pictures. The B buffer dedicated internal buffer 437 is a buffer for storing B picture data of a specified PTS, and is configured with an area in which data for one frame can be stored. The internal buffer 438 dedicated to the I and P pictures is a buffer for storing data of the I and P pictures decoded by the decoding processing unit 433, and is an area in which data for the frames of the I and P pictures included in the 2GOP can be stored. Constitute. The internal buffer 438 dedicated to I and P pictures stores the PTS value and I and P picture data in association with each other. The areas of the internal buffers 437 and 438 are not particularly limited, and can be appropriately designed to store data for an arbitrary frame. However, in order to realize the present invention, the internal buffer 437 dedicated to B pictures is configured with an area capable of storing at least one frame of data, and the internal buffer 438 dedicated to I and P pictures is at least 2 GOPs. It is preferable to configure an area that can store data for the included I and P picture frames.

  When receiving the video code data stored in Buffer 41, the first PTS check unit 431 performs the first PTS check based on the designated PTS received from the Demux 3.

  The first PTS check unit 431 outputs only the I and P picture data to the second PTS check unit 432 until the designated PTS, and the B picture data is discarded by the first PTS check unit 431. 2 is controlled so as not to be output to the PTS check unit 432 in FIG. Also, when the designated PTS is B picture data, the first PTS check unit 431 outputs the B picture data to the second PTS check unit 432, and the data after the designated PTS is the first PTS. Control is performed so that the data is discarded by the check unit 431 and not output to the second PTS check unit 432. However, if there is I or P picture data in the data after the designated PTS, control is performed so that the I and P picture data is output to the second PTS check unit 432. Accordingly, the first PTS check unit 431 can output all the I and P picture data and the B picture data of the designated PTS to the second PTS check unit 432.

  When the second PTS check unit 432 receives data from the first PTS check unit 431, the second PTS check unit 432 performs a second PTS check based on the designated PTS received from the Demux 3.

  If the data received from first PTS check unit 431 is B picture data of the designated PTS, second PTS check unit 432 outputs the accepted B picture data of the designated PTS to decode processing unit 433. To control. In addition, when the data received from the first PTS check unit 431 is I / P picture data, the second PTS check unit 432 stores the I / P picture dedicated internal buffer 438 in the frame memory processing unit 434. When the PTS values match when compared with the stored PTS values of the I and P pictures, the I and P picture data received from the first PTS check unit 431 is discarded by the second PTS check unit 432 Then, control is performed so as not to output to the decoding processing unit 433. If the PTS values do not match, control is performed so that the I and P picture data received from the first PTS check unit 431 is output to the decode processing unit 433. As a result, the second PTS check unit 432 outputs the B picture data of the designated PTS and the I and P picture data not stored in the internal buffer 438 dedicated to the I and P pictures to the decode processing unit 433. Can do.

  When receiving data from the second PTS check unit 432, the decoding processing unit 433 performs known decoding processing such as variable length decoding, inverse quantization, and inverse DCT. When the data received from the second PTS check unit 432 is P or B picture data, the decoding processing unit 433 stores the I stored in the internal buffer 438 dedicated to I and P pictures in the frame memory processing unit 434. , P motion picture is referred to, and motion compensation unit 436 performs known motion compensation. The decode processing unit 433 outputs the decoded data to the frame memory processing unit 434.

  When the frame memory processing unit 434 receives data from the decoding processing unit 433 and the received data is B picture data, the frame memory processing unit 434 stores the data in the internal buffer 437 dedicated to the B picture. Further, in the case of I, P picture data, it is stored in the internal buffer 438 dedicated to the I, P picture in association with the PTS value. The frame memory processing unit 434 stores the data of the I and P pictures in the free area if the internal buffer 438 dedicated to the I and P pictures has a free area. Based on the PTS, the area of the PTS value larger than the designated PTS is cleared, and the newly received I and P picture data is stored. If there is still no free area, the area with the smallest PTS value is cleared and the newly received I and P picture data is stored.

  The third PTS check unit 435 reads the data of the designated PTS from the internal buffers 437 and 438 in the frame memory processing unit 434 based on the designated PTS received from the Demux 3, and outputs the read data to the Video Render 5.

<Example of processing operation of Video Decoder 43>
Next, a processing operation example of the Video Decoder 43, which is a characteristic part of the present embodiment, will be described with reference to FIG. The following processing operations are processing operations when a designated PTS is received.

  First, the first PTS check unit 431 determines whether or not the designated PTS received from the Demux 3 is a B picture (step S10).

  When the designated PTS received from the Demux 3 is a B picture (step S10 / Yes), the B picture and all I and P pictures of the designated PTS included in the GOP are set as decoding targets (step S11).

  If the designated PTS received from Demux3 is an I or P picture (step S10 / No), all the I and P pictures included in the GOP are to be decoded (step S12).

  The second PTS check unit 432 refers to the internal buffer 438 dedicated to I and P pictures in the frame memory processing unit 434, and outputs only data not stored in the internal buffer 438 to the decoding processing unit 433. Decoding is performed at 433 (step S13).

  The frame memory processing unit 434 stores the data decoded by the decoding processing unit 433 in the internal buffers 437 and 438 (step S14). Specifically, when the data decoded by the decoding processing unit 433 is a B picture, it is stored in the internal buffer 437 dedicated to the B picture, and when the data decoded by the decoding processing unit 433 is an I, P picture, I, The data is stored in the internal buffer 438 dedicated to P pictures in association with the PTS value.

  The third PTS check unit 433 refers to the internal buffers 437 and 438 of the frame memory processing unit 434 based on the designated PTS received from the Demux 3, and outputs data corresponding to the designated PTS to the Video Render 5 (step S15). Thereby, the Video Render 5 can display the image data of the designated PTS decoded by the Decoder 4 on the display 7.

<Operation / Effect of Playback Device 100 of this Embodiment>
As described above, the playback apparatus 100 according to the present embodiment outputs the image data of the designated PTS using the decoded image data of the I and P pictures included in the internal buffer 348. As a result, the playback apparatus 100 of the present embodiment can shorten the processing time until the designated PTS image data is output.

  The above-described embodiment is a preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiment alone, and various modifications are made without departing from the gist of the present invention. Implementation is possible.

  For example, the playback apparatus 100 of the present embodiment described above has a file reader 2 and a Demux 3 as shown in FIGS. 1 and 4, and a function of reading MPEG data from the memory 1 (function of the file reader 2). And the function to separate the MPEG data (Demux3 function). However, the file reader 2 function and the Demux 3 function can be integrated as one function.

  Further, the control operation in each device constituting the playback device 100 in the present embodiment described above can be executed using hardware, software, or a combined configuration of both.

  In the case of executing processing using software, it is possible to install and execute a program in which a processing sequence is recorded in a memory in a computer incorporated in dedicated hardware. Alternatively, the program can be installed and executed on a general-purpose computer capable of executing various processes.

  For example, the program can be recorded in advance on a hard disk or ROM (Read Only Memory) as a recording medium. Alternatively, the program can be stored (recorded) temporarily or permanently in a removable recording medium. Such a removable recording medium can be provided as so-called package software. The removable recording medium includes a floppy (registered trademark) disk, a CD-ROM (Compact Disc Read Only Memory), an MO (Magneto optical) disk, a DVD (Digital Versatile Disc), a magnetic disk, a semiconductor memory, and the like.

  The program is installed in the computer from the removable recording medium as described above. In addition, it is wirelessly transferred from the download site to the computer. In addition, it is transferred to the computer via a network by wire.

  Further, the playback device 100 in the present embodiment is not only executed in time series according to the processing operation described in the above embodiment, but also the processing capability of the device that executes the processing, or in parallel as necessary It can also be constructed to run individually.

  The present invention is applicable to a technique for reproducing an MPEG standard code.

100 playback device 1 memory 2 file reader (acquisition means)
3 Demux
4 Decoder (control means)
41, 42 Buffer
43 Video Decoder
431 First PTS check unit 432 Second PTS check unit 433 Decode processing unit 434 Frame memory processing unit 435 Third PTS check unit 436 Motion compensation processing unit 437 Internal buffer dedicated to B picture 438 Internal dedicated to I and P picture Buffer 44 Audio Decoder
5 Video Render
6 Audio Render
7 Display 8 Speaker

Claims (8)

When a designated PTS (Presentation Time Stamp) for outputting image data is received, a first GOP (Group of Picture) including the data of the designated PTS and a second immediately before the first GOP An acquisition means for acquiring at least GOP data;
Control means for decoding the data acquired by the acquisition means up to the data of the designated PTS, and outputting the image data of the designated PTS;
A playback apparatus comprising: A buffer that stores image data of decoded I (Intra-coded) pictures and P (Predictive-coded) pictures;
The control means includes
2. The reproducing apparatus according to claim 1, wherein the image data of the designated PTS is output using the decoded I picture and P picture image data stored in the buffer. The control means includes
Among the data of the first GOP and the second GOP, I picture and P picture data not stored in the buffer are decoded up to the designated PTS data, and the designated PTS image data is output. The reproducing apparatus according to claim 1 or 2, characterized in that The control means includes
Store the decoded I picture and P picture image data in the buffer,
4. The image data of the designated PTS is output using image data of decoded I picture and P picture stored in the buffer when the designated PTS is received. 5. Playback device. The control means includes
When the image data of the designated PTS is an I picture and the image data of the I picture is stored in the buffer, the decoded I picture image data stored in the buffer is output, and the I A first control unit that decodes the image data of the I picture and outputs the decoded image data of the I picture when the image data of the picture is not stored in the buffer;
When the image data of the designated PTS is a P picture and the image data of the P picture is stored in the buffer, the image data of the decoded P picture stored in the buffer is output, and the P If a picture is not stored in the buffer, the decoded I picture or P picture image data stored in the buffer is used to decode the P picture image data, and the decoded P picture Second control means for outputting the image data of
When the image data of the designated PTS is a B (Bi-directionally predictive-coded) picture, the image data of the B picture is converted using the image data of the decoded I picture or P picture stored in the buffer. Third control means for decoding and outputting the decoded image data of the B picture;
5. The playback apparatus according to claim 2, wherein the playback apparatus includes: The control means includes
Storing the image data of the I picture decoded by the first control means in the buffer;
6. The reproducing apparatus according to claim 5, wherein the image data of the P picture decoded by the second control means is stored in the buffer. A control method performed by a playback device,
When a designated PTS (Presentation Time Stamp) for outputting image data is received, a first GOP (Group of Picture) including the data of the designated PTS and a second immediately before the first GOP An acquisition process for acquiring at least GOP data;
Decoding the data acquired in the acquisition step up to the data of the designated PTS, and outputting the image data of the designated PTS;
A control method characterized by comprising: When a designated PTS (Presentation Time Stamp) for outputting image data is received, a first GOP (Group of Picture) including the data of the designated PTS and a second immediately before the first GOP An acquisition process that acquires at least GOP data;
Decoding the data acquired in the acquisition process up to the data of the designated PTS, and outputting the image data of the designated PTS;
A program that causes a computer to execute.

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