JP2009049855A - Content-playback apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a content-playback apparatus capable of outputting a frame of a final GOP in a case where the end of a file is reached by fast forwarding. <P>SOLUTION: A content-playback apparatus includes a decision means 25 for deciding on the presence/absence of image data in a skip destination; a calculating means 12 for calculating the time stamp of a key image frame in a final group to which a final image frame belongs, based on a time stamp of the final image frame in contents and the number of frames in dividing a plurality of image frames into groups, when there are not image data; a temporal position acquiring means 24 for acquiring a temporal position of arbitrary image data, preceding the image data of the key image frame; a request means 10 for requesting acquisition of content data containing image data following the temporal position; and an acquisition means 25 for decoding image data after the key image frame of the final group, based on the time stamp of an image frame, corresponding to the image data received in response to the request and the time stamp of the key image frame. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a content reproduction apparatus for reproducing video / audio and the like via a network.

  Currently, MPEG (Moving Picture Experts Group), which is a moving image compression technique, is widely used in DVD-Video, digital television broadcasting, and the like. As shown in FIG. 9, MPEG is composed of I, B, and P-Picture (picture). The I picture is an Intra encoded image (intra-frame encoded image), the P picture is a Predictive encoded image (inter-frame forward predictive encoded image), and the B picture is a Bidirectionally predictive encoded image (bidirectional predictive encoded image). is there.

  The P picture is created based on the previous screen (I picture or P picture), and the B picture is created based on the previous and subsequent screen data (I picture or P picture). For this reason, the P picture and the B picture do not become a complete frame with only one screen. Therefore, random access is realized in units of GOP (Group Of Picture), which is a group of several frames. In the example of FIG. 9, 1 GOP is 15 frames.

In addition, network media players (also referred to as network player devices) that play back video / audio recorded on a server over a network via a network due to the speedup of PCs (personal computers) and network devices are also described below. (See Patent Document 1). Also, in order to realize interoperability between servers and clients of various manufacturers, standardization is being promoted by Digital Living Network Alliance (hereinafter also referred to as DLNA, see Non-Patent Document 2 below). However, since file access using the network is slower than normal (local) file access, trick play such as fast forward and fast reverse is different from local video playback. DLNA presents skip processing (fast-forward processing and fast-reverse processing) as shown in FIG. 10 as one method for realizing fast-forward / fast-reverse.
http://www.regza.jp/product/tv/z2000/index.html http://itpro.nikkeibp.co.jp/NNW/index.html, “First DLNA” Nikkei Network March 2006 issue

  However, when the end of the file is reached by fast-forwarding by skip processing (fast-forward processing), a frame near the end cannot always be output. For example, as shown in FIG. 11, when the seek position exceeds the end of the file, a frame far from the last frame is displayed last. This phenomenon appears particularly remarkably during high-speed fast feed such as 60 times speed and 100 times speed (because the skip size is large). In order to solve this, it is necessary to know the seek position (number of bytes from the beginning) of the final GOP. However, currently widely used video data of the MPEG2 standard supports a variable bit rate. An accurate seek position of the final GOP cannot be obtained from the bit rate.

  The present invention is to solve the above-described problems, and provides a content playback apparatus capable of outputting a frame of the final GOP (an example of the final group described above) when the end of a file is reached by fast-forwarding. For the purpose.

  To achieve the above object, according to the present invention, content data including image data and audio data constituting a plurality of image frames, the content data acquired from an external or internal storage means is decoded. In the content playback apparatus that performs skip playback by receiving a skip playback instruction for skipping the content and skipping the content every predetermined amount of image data when the content is decoded and played back by the means, the skip playback received Based on the instruction, when it is determined that the image data does not exist at the skip destination, and a determination unit that determines whether the image data exists at the skip destination, the final image in time series of the content A time stamp indicating frame time information and a plurality of the image frames Based on the predetermined number of frames when divided into a plurality of groups with a fixed number of frames, obtained by intra-frame coding that is the basis of the final group to which the final image frame of the content belongs. Calculating means for obtaining the time stamp of the key image frame to be obtained, and time arrangement of the entire image data of the content of arbitrary image data time-sequentially before the image data constituting the key image frame of the final group Time position obtaining means for obtaining a temporal position in the image by a predetermined calculation or program, and obtaining the content data including the image data time-sequentially after the obtained time position from the external or internal storage means Requesting means for making a request to perform the request, and corresponding to the image data received by the request Obtain image data corresponding to subsequent image frames including the key image frame of the final group based on the time stamp of the image frame and the time stamp of the key image frame of the final group. Then, a content reproducing apparatus is provided, comprising: an acquisition unit that causes the decoding unit to decode. With this configuration, the frame of the last GOP (an example of the last group described above) can be output when the end of the file is reached by fast-forwarding. Note that the above-described group corresponds to, for example, a GOP. The key image frame corresponds to, for example, an I picture frame described later. The predetermined image data amount corresponds to, for example, the number of skip bytes described later. The predetermined calculation refers to an operation for obtaining seek_pos using, for example, an expression (2) described later, and the predetermined program refers to an algorithm for obtaining seek_pos using, for example, expression (2).

  The content reproduction apparatus of the present invention has the above-described configuration, and can output a frame of the last GOP (an example of the above-mentioned final group) when the end of the file is reached by fast-forwarding.

  Hereinafter, a network player device (corresponding to a content reproduction device) of the present invention will be described. FIG. 1 shows an example of the configuration of a network player device (hereinafter also simply referred to as a player) that can output the frame of the final GOP when the end of an MPEG file (consisting of MPEG data) is reached by fast-forwarding. FIG. As shown in FIG. 1, the player 100 is connected to the same communication network 102 as the server 101. The server 101 in the embodiment of the present invention has an MPEG2-PS format video file (hereinafter also referred to as an MPEG file), and transmits an MPEG file to the player 100 in response to a request (request) from the player 100. It has a function to do. The server 101 also has a byte seek function (seeks an arbitrary position from the beginning of data).

  The player 100 can receive and play back the MPEG file that the server 101 has, and has fast forward and fast reverse functions. In the embodiment of the present invention, it is assumed that the player 100 knows in advance the MPEG file that the server 101 has and its file size.

  Here, a system structure of MPEG2-PS used in the embodiment of the present invention will be briefly described. In MPEG2-PS data (MPEG data), a plurality of individual streams (Video (video), Audio (audio), etc.) are packetized to an appropriate length and multiplexed. Usually, it is handled in a unit called a pack in which a plurality of (or one) packets are bundled. FIG. 2 shows the structure of MPEG2-PS data. As shown in FIG. 3, each packet includes a header portion (portion from the packet start code to the rest) and a data portion (data portion).

  The packet start code is a code number assigned to the packet. The stream ID is a stream ID of video data and audio data, and is defined by the MPEG standard. The packet length indicates the packet length, the flags indicate the packet type, the header length indicates the header length, and the time stamp indicates time information for AV synchronization. It is.

  Also, an SCR (System Clock Reference) is written in the pack header shown in FIG. The SCR is a value for setting the decoder clock when the decoder performs AV synchronization. That is, the decoder realizes AV synchronization using the SCR in the pack header and the time stamps of the video packet and the audio packet. A bit rate and the like are written in a system header (not shown). The above is the outline of the MPEG2-PS system structure.

  Hereinafter, the configuration of the player 100 will be described with reference to FIG. First, the transmission / reception means 10 will be described. The transmission / reception means 10 holds a received data amount counter that counts the received data amount. The transmission / reception means 10 receives a control command from the control means 25 described later, requests the server 101 for an MPEG file (MPEG data), receives the MPEG data, and writes the received MPEG data in the buffer means 11. Here, the control commands received by the transmission / reception means 10 are three types of commands: a reception start command, a reception stop command, and a counter reset command.

  When a reception start command is received, MPEG data is received from the server 101 and the received MPEG data is written in the buffer means 11. Further, the received data amount counter is incremented by the received data amount. If a reception stop command is received, reception is stopped. When a counter reset command is received, the received data amount counter is cleared to zero.

  The buffer unit 11 buffers the MPEG data received from the server 101 by the transmission / reception unit 10 and outputs it to the Demux unit 12. Next, the bit rate management means 20, GOP management means 21, time information management means 22, and frame rate management means 23 will be described. The bit rate management means 20 stores the bit rate information input from the Demux means 12 described above. The GOP management means 21 stores the number of pictures in the GOP input from the video decoding means 15 described later.

  The time information management unit 22 stores time information input from the video decoding unit 15, that is, a time stamp of a picture processed by the video decoding unit 15. The frame rate management means stores the frame rate information input from the video decoding means 15.

  Next, the Demux means 12 will be described. The Demux unit 12 receives a control command from the control unit 25 to be described later, and separates the MPEG data in the buffer unit 11 into a video packet, an audio packet, unillustrated system information (system information) and bit rate information, and a changeover switch. The video packet is output to the video buffer means 14 via the (SW) 26, the audio packet is output to the audio buffer means 17, and system information (not shown) is output to the system decoding means 13. The Demux unit 12 outputs the bit rate information to the bit rate management unit 20.

  Here, a control command from the control means 25 to the Demux means 12 will be described. Control commands output from the control unit 25 to the Demux unit 12 include a normal Demux and a Demux with a time stamp designation. When receiving the normal Demux command, the Demux unit 12 separates the MPEG data in the buffer unit 11 as described above. On the other hand, when a time stamp designation Demux command is received, only data after the designated time stamp is output.

  Next, the video decoding means 15 will be described. The video decoding unit 15 operates in response to a decoding start command, a capture command, and a decoding stop command from the control unit 25, decodes the video data written in the video buffer unit 14, and outputs it to the video output unit 16. When GOP information is detected during decoding, it is output to the GOP information management means 21. When a time stamp is detected, it is output to the time information management means 22 and frame rate information is detected. Are output to the frame rate management means 23, respectively. When a capture command is received, the control means 25 is notified of the capture completion at the time when the decoding of one picture is completed from the start of decoding.

  Next, the audio decoding means 18 will be described. The audio decoding unit 18 operates in response to a control command from the control unit 25. The audio decoding means 18 receives two types of control commands: a decode start command and a decode stop command. When the decoding start command is received, the audio data written in the audio buffer means 17 is decoded and output to the audio output means 19. On the other hand, when the decoding stop instruction is received, the decoding process is stopped.

  The video output means 16 displays the image decoded by the video decoding means 15 on a display means (not shown). The audio output means 19 outputs the audio data decoded by the audio decoding means 18.

  The final GOP seek position calculation means 24 includes the bit rate stored in the bit rate management means 20, the number of GOP pictures stored in the GOP information management means 21, and the time stored in the time information management means 22. The seek position of the final GOP is obtained from the stamp and output to the control means 25. Here, the seek position information represents the number of bytes from the beginning of the MPEG file. The control means 25 receives commands from the user, controls each module (each means) of the player 100, and realizes user operations. The operation of the control means 25 will be described in the operation of the player 100 described later. The above is an example of the configuration of the player according to the embodiment of the present invention.

  Next, the operation of the player according to the embodiment of the present invention will be described with reference to FIG. When the player 100 is activated, the control unit 25 waits for a command (user operation) from the user and determines what the user operation is (step S401). If a playback command is received from the user, the process proceeds to playback step S402. If a fast forward command is received, the process proceeds to fast forward capture step S404. If a fast reverse command is received, the process proceeds to fast reverse capture step S406. If a command is received, the process ends.

  First, a case where a reproduction command is received will be described. In step S402, MPEG data is received from the server 101, decoded, and output. In step S403, it is determined what the user operation is after reproduction (step S403). If it is a stop command, the process proceeds to stop step S408, and if it is an end command, the process ends. When there is no user operation, the process returns to the reproduction step S402 and the reproduction process is continued. If it is a fast-forward command, the process proceeds to fast-forward capture step S404. If it is a fast-return command, the process proceeds to fast-reverse capture step S406.

  In step S401, if the operation from the user is a fast-forward command, the process proceeds to fast-forward capture step S404. If there is a stop command in step S405, the process proceeds to stop step S408. On the other hand, if the operation from the user is a fast reverse command in step S401, the process proceeds to fast reverse capture step S406, and if there is a stop command in step S407, the process proceeds to stop step S408. In stop step S408, a stop command is issued to the video decoding unit 15 and the audio decoding unit 18, a reception stop command is issued to the transmission / reception unit 10, the reception data amount counter of the transmission / reception unit 10 is cleared to zero, and the process returns to step S401. Wait for user operation again.

  Details of the reproduction step S402 will be described with reference to FIG. FIG. 5 is a flowchart showing an example of the operation of the reproduction step S402. In the reception step S501, the transmission / reception means 10 receives MPEG data and writes it in the buffer means 11. In the Demux step S502, the Demux means 12 separates the MPEG data in the buffer means 11. In the video decoding step S503, the video decoding unit 15 decodes the separated video data and outputs the decoded video data to the video output unit 16. In the audio decoding step S504, the audio decoding means 18 decodes the audio data written in the audio buffer means 17 and outputs it to the audio output means 19.

  Here, the details of the video decoding step S503 will be described with reference to FIG. In the decoding step S 601, the video decoding unit 15 decodes the video data written in the video buffer unit 14 and outputs it to the video output unit 16. In step S602, the video decoding unit 15 determines the presence or absence of GOP information. If GOP information is present, the GOP information is stored in the GOP management unit 21 in GOP information management step S603.

  On the other hand, if there is no GOP information, in step S604, the video decoding unit 15 determines whether or not there is a time stamp. If there is a time stamp, the video decoding unit 15 stores it in the time information management unit 22 in time stamp management step S605. . On the other hand, if there is no time stamp, in step S606, the video decoding unit 15 determines the presence / absence of frame rate information. If there is frame rate information, the video decoding unit 15 sends the frame rate management unit 23 to the frame rate management unit 23 in frame rate management step S607. Remember. On the other hand, if there is no frame rate information, the process ends. By performing the above processing, MPEG data received from the server 101 can be reproduced, and GOP information, time information, and frame rate information can be obtained.

  Next, the fast reverse process will be described. As shown in FIG. 4, the fast reverse process is realized by repeatedly performing the fast reverse capture process (steps S406 and S407). In the fast reverse capture step S406, the seek position of the MPEG data received from the server 101 is determined, and the MPEG data is requested to the server 101 from the seek position. Then, the received data is separated (Demux), decoded, and an image is captured (acquired). Details will be described later.

  In step S407, it is determined what the user operation is, and if there is no user operation, the process returns to the fast reverse capture step S406 to continue the process. If there is a reproduction command from the user, the process proceeds to reproduction step S402, and if there is a stop command from the user, the process proceeds to stop step S408.

  Here, the fast reverse capture step S406 will be described with reference to FIG. In the seek position determination step S701, a value obtained by subtracting an arbitrary number of skip bytes from the value of the reception data amount counter of the transmission / reception means 10 is set as the seek position. If the number of skip bytes is reduced, low-speed rewind is performed, and if it is increased, high-speed rewind is performed. In request step S702, the control unit 25 sets the seek position obtained in step S701 in the received data amount counter of the transmission / reception unit 10, and the transmission / reception unit 10 requests the server 101 for data from the seek position.

  In the reception step S 703, the transmission / reception unit 10 receives MPEG data from the server 101 and writes the received data in the buffer unit 11. In the Demux step S 704, the Demux unit 12 separates the video data from the MPEG data written in the buffer unit 11 and writes the video data in the video buffer unit 14. At this time, other than the video data is discarded. In the video decoding step S705, the video decoding means 15 performs the same process as the video decoding step S503 in FIG.

  In step S706, it is determined whether or not one image has been output in video decoding step S705. If not, the process returns to reception step S703 to continue the processing. When one image is output, the process of fast reverse capture step S406 ends. The above is the details of the fast reverse capture step S406. Thereby, skip and capture are repeated, and the operation of fast reverse processing is realized.

  Next, the fast-forward process will be described. Similar to the fast reverse process, the fast forward process is realized by repeatedly performing the fast forward capture process (steps S404 and S405) as shown in FIG. In the fast forward capture step S404, the seek position of the MPEG data received from the server 101 is determined, the data is received, and the image is captured. Details will be described later. In step S405, it is determined what the user operation is, and if there is no user operation, the process returns to the fast-forward capture step S404 and the process is continued. If there is a reproduction command from the user, the process proceeds to reproduction step S402, and if there is a stop command from the user, the process proceeds to stop step S408.

  Here, the fast-forward capture step S404 will be described with reference to FIG. Here, the procedure of FIG. 8 can be divided into two procedures: steps S801 to S807 for the purpose of capturing only and procedures for capturing the frame of the final GOP. The case of only capture is realized by executing steps S801 to S807. On the other hand, when capturing the frame of the last GOP, steps S809 to S816 are executed, the seek position of the final GOP and the time stamp of the final I picture are obtained, and then the steps I803 to S807 are executed. This can be achieved by capturing a picture frame. Details are described below.

  In seek position determination step S801, when the control means 25 receives a fast-forward instruction (skip reproduction instruction) from the user while MPEG data (content) is being reproduced, the value of the received data amount counter of the transmission / reception means 10 is calculated. A value obtained by adding an arbitrary number of skip bytes (predetermined amount of image data) is set as a seek position. If the number of skip bytes is reduced, low-speed fast-forwarding is performed, and if it is increased, high-speed fast-forwarding is performed.

  In seek position determination step S802, the control means 25 (determining means described above) determines whether or not the seek position obtained in seek position determination step S801 is within the MPEG file size range. That is, based on the fast-forward instruction, it is determined whether or not MPEG data exists at the skip destination. If it is within the range, the process proceeds to request step S803. If it is out of the range, that is, when a value larger than the MPEG file size is obtained, the process proceeds to final frame seek position determination step S809 to output the final I picture. Transition.

  In request step S803, the transmission / reception means 10 requests the server 101 for MPEG data at the seek position obtained in step S801 or the final I picture seek position determination step S816 described later. In the reception step S804, the transmission / reception means 10 receives MPEG data from the server 101 and writes the received MPEG data in the buffer means 11. In the Demux step S 805, the Demux unit 12 separates video data from the MPEG data written in the buffer unit 11 and writes the video data in the video buffer unit 14. At this time, other than the video data is discarded.

  In the video decoding step S806, the video decoding means 15 performs the same process as the video decoding step S503 in FIG. In step S807, the control unit 25 or the video decoding unit 15 determines whether one image is output in the video decoding step S806. If not, the process proceeds to step S808, and the image is output. The fast-forward capture step ends. In step S808, the transmission / reception means 10 determines whether or not reception is completed. That is, it is determined whether the end of the MPEG file has been received.

  If the reception is not finished, the process returns to the reception step S804 and the processing is continued. On the other hand, the reception end is a case where the end of the MPEG file is reached without being captured, and the process proceeds to the final frame seek position detection step S809 in order to output the final GOP frame.

  Here, the procedure (steps S809 to S816) for capturing the frame of the final GOP will be described. In the final frame seek position determination step S809, for example, the final GOP seek position calculation unit 24 or the control unit 25 determines the seek position of the final frame from the bit rate stored in the bit rate management unit 20. The seek position can be obtained using, for example, the following equation (1).

  Here, bitrate is a bit rate stored in the bit rate information management unit 20, and frame_rate is a frame rate stored in the frame rate information management unit 23. file_size is the size of the MPEG file. However, the seek position obtained by equation (1) is not necessarily the seek position of the final frame. Therefore, first, the time stamp of the final frame is obtained by executing steps S810 to S814. In request step S810, the transmitting / receiving means 10 requests the server 101 for MPEG data from the seek position obtained in step S809.

  In the reception step S811, the transmission / reception means 10 writes the received data into the buffer means 11, and in the Demux step S812, the Demux means 12 separates the video data from the MPEG data written in the buffer means 11, and sends it to the video buffer means 14. Write. At this time, other than the video data is discarded. In time stamp detection step S813, the video decoding means 15 detects the time stamp of the video data and stores it in the time information management means 22. In step S814, the transmission / reception means 10 determines whether or not reception is complete. That is, it is determined whether the end of the MPEG file has been received.

  If the end of the MPEG file has not been received, the process returns to the reception step S811, and the processing is continued. By performing the processing from step S811 to S813, the time stamp of the last frame is written in the time information storage unit 22. Next, in the Demux means setting step S815, the time stamp of the final I picture is obtained, and the Demux means 12 is instructed to specify the time stamp. The time stamp of the final I picture is a value obtained by subtracting the number of GOPs from the time stamp of the final frame obtained by the processing from steps S809 to S813.

  That is, the Demux unit 12 (the calculation unit described above) includes a time stamp indicating time information of an image frame in a final image frame in time series of content, and a plurality of groups of image frames with a predetermined number of frames ( GOP) based on the predetermined number of frames and the time of the key image frame (final I picture) obtained by intraframe coding as the basis of the final group, which is the group to which the final image frame of the content belongs. Ask for a stamp.

  Next, in the final I picture seek position determination step S816, the final GOP seek position calculation means 24 (time position acquisition means described above) obtains the seek position of the final I picture that is a position near the final I picture. In other words, the final GOP seek position calculation means 24 in the time sequence of the entire image data of the content of arbitrary image data time-sequentially before the image data constituting the final key image frame (final I picture frame) A temporal position (seek position) is determined by a predetermined program (a program corresponding to Equation (2) described later).

  The seek position is determined by the GOP information stored in the GOP information management unit 21 (GOP_frames: number of pictures of 1 GOP) and the bit rate (bitrate) stored in the bit rate management unit 20. Based on the MPEG file size (file_size) and the frame rate (frame_rate), the following equation (2) is used.

  Then, the transmitting / receiving means 10 (the request means described above) requests MPEG data from the obtained seek position (that is, after the seek position in time series), and the time stamp of the last I picture frame obtained earlier. The I picture of the final GOP can be captured based on That is, the control unit 25 (the acquisition unit described above) performs the time stamp of the image frame based on the image data obtained by receiving the content data including the image data after the determined position (seek position), and the final key image frame ( The final key image frame is acquired (captured) based on the time stamp of the last I picture frame), and the subsequent image frames including the final key image frame are displayed on the video decoding unit 15. By executing the request steps S803 to S807 as described above, the I picture of the final GOP can be captured.

  As described above, the MPEG data at the end of the MPEG file is received, the time stamp of the final frame is obtained, the time stamp of the I picture of the final GOP is obtained from the time stamp and GOP information, and the seek of the final I picture is further obtained. The frame capture of the final GOP can be realized by obtaining the position and using the MPEG data received from the obtained seek position and the time stamp of the I picture of the final GOP. This makes it possible to always output the frame of the final GOP even when fast-forwarding by skipping and reaching the end of the MPEG file.

  Note that by multiplying GOP_frames in Expression (2) by a number greater than 1, for example, the seek position is closer to the start point of the content, so that the amount of MPEG data to be received increases, and the I picture frame of the final GOP is surely received. Can be captured. By receiving extra MPEG data in this way, the I picture frame of the final GOP can be reliably captured even when the first MPEG data cannot be received successfully due to a malfunction at the start of reception. It is useful to receive a lot of MPEG data. Also, MPEG data is requested from the server 101 from the obtained seek position, but since MPEG data is received once when obtaining the time stamp of the I picture of the final GOP, the MPEG data received once is predetermined. By storing in the storage area, it is possible to eliminate the need for MPEG data again.

  Further, the above-described player functions may be realized by a computer by a program. This program may be read from a recording medium and loaded into a computer, or may be transmitted via a communication network and loaded into a computer.

  The network player device according to the present invention can output a frame of the final GOP (an example of the above-mentioned final group) when fast-forwarding reaches the end of the file. This is useful for a network player device that reproduces

It is a block diagram which shows an example of a structure of the content reproduction apparatus (network player apparatus) which concerns on embodiment of this invention. It is a figure which shows an example of the structure of MPEG2-PS data in embodiment of this invention. It is a block diagram which shows an example of the structure of the packet in embodiment of this invention. It is a flowchart which shows an example of the operation | movement flow of the content reproduction apparatus which concerns on embodiment of this invention. It is a flowchart for demonstrating the detail of the reproduction | regeneration step in embodiment of this invention. It is a flowchart for demonstrating the detail of the video decoding step in embodiment of this invention. It is a flowchart for demonstrating the detail of the fast reverse capture step in embodiment of this invention. It is a flowchart for demonstrating the detail of the fast-forward capture step in embodiment of this invention. It is a figure for demonstrating MPEG which exists conventionally. It is a figure for demonstrating one of the methods of implement | achieving the conventional fast forward / fast reverse. It is a figure for demonstrating the problem that the seek position in the past will exceed the end of a file.

Explanation of symbols

10 Transmission / reception means (request means)
11 Buffer means 12 Demux means (calculation means)
13 System decoding means 14 Video buffer means 15 Video decoding means 16 Video output means 17 Audio buffer means 18 Audio decoding means 19 Audio output means 20 Bit rate management means 21 GOP information management means 22 Time information management means 23 Frame rate management means 24 Final GOP seek position calculation means (time position acquisition means)
25 Control means (judgment means, acquisition means)
26 changeover switch (SW)
100 player 101 server 102 communication network

Claims (1)

Content data including image data and audio data constituting a plurality of image frames, and the content data acquired from an external or internal storage means is decoded by a decoding means, and the content is reproduced. In a content playback apparatus that performs skip playback by accepting a skip playback instruction for skipping playback of the content by skipping each image data amount,
Determining means for determining whether or not the image data exists at a skip destination based on the received skip reproduction instruction;
When it is determined that the image data does not exist at the skip destination, a time stamp indicating time information of the last image frame in time series of the content, and a plurality of groups of the plurality of image frames with a predetermined number of frames The time stamp of the key image frame obtained by intra-frame coding that is the basis of the final group that is the group to which the final image frame of the content belongs based on the predetermined number of frames Calculating means for obtaining
A time position for obtaining a temporal position in a time sequence of the entire image data of the content of arbitrary image data time-sequentially before the image data constituting the key image frame of the final group by a predetermined calculation or program Acquisition means;
Request means for making a request for acquiring the content data including image data after time series from the obtained temporal position from the external or internal storage means;
Including the key image frame of the final group based on the time stamp of the image frame corresponding to the image data received by the request and the time stamp of the key image frame of the final group. Acquisition means for acquiring image data corresponding to subsequent image frames and decoding the decoding means;
A content playback apparatus comprising:

Images