JP2007028209A - Content reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a content reproducing device capable of improving operability during the reproduction, and also, capable of accurately synchronizing contents with each other. <P>SOLUTION: An HDD 44 reproduces four MPEG-PSs recorded on a hard disk 22 in parallel. A CPU 38 changes each of reproduction positions of the four MPEG-PSs when receiving positional change operation through an operation panel 36. The CPU 38 repeatedly detects a PTS corresponding to the current reproduction position from each of the four contents through MPEG decoders 28a-28d. The CPU 38 adjusts each of the reproduction positions of the four MPEG-PSs so that the time respectively shown by the detected PTSs is coincident with each other when receiving synchronization recovery operation. Consequently, it is possible to improve the operability during the reproduction, and also, to accurately synchronize the contents with each other. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a content reproduction apparatus, and more particularly to, for example, a content reproduction apparatus that reproduces a plurality of contents synchronously.

Conventionally, as this type of apparatus, one disclosed in Patent Document 1 is known. In this prior art, a buffer and a register are prepared for each of a plurality of contents. Each of the plurality of contents is stored in a corresponding buffer and output at the time set in the corresponding register. By setting the same output time in a plurality of registers, it is possible to accurately synchronize content.
JP-A-6-214689 [G06F 3/00, 1/14, H04N 5/907]

However, in the prior art, an operation for changing the playback speed or changing the playback position is not envisioned, and sufficient operability cannot be obtained. In addition, it is difficult to accurately synchronize contents in relation to such operations.
Therefore, a main object of the present invention is to provide a content reproduction apparatus that can improve operability during reproduction and can accurately synchronize content.

  The content reproduction apparatus according to the first aspect of the invention is a content reproduction apparatus that reproduces a plurality of contents each having time information that is repeatedly described in parallel, and when each of the plurality of contents is reproduced when a position change operation is accepted. Position change means (S97) for changing the position to the designated position, detection means (S131 to S135) for repeatedly detecting time information corresponding to the current playback position from each of the plurality of contents, and synchronous recovery after the change operation of the position change means It is characterized by comprising adjusting means (S103, 105, S109) for adjusting the reproduction position of each of the plurality of contents so that the times indicated by the time information detected by the detecting means when the operation is accepted are matched with each other.

  A plurality of contents each having time information repeatedly described are reproduced in parallel. When the position change operation is accepted, the reproduction position of each of the plurality of contents is changed to a designated position by the position change unit. The detecting means repeatedly detects time information corresponding to the current reproduction position from each of the plurality of contents. The adjusting means adjusts the reproduction position of each of the plurality of contents so that the times indicated by the time information detected by the detecting means coincide with each other when a synchronization recovery operation is received after the changing operation of the position changing means.

  In other words, the playback position of each of the plurality of contents is changed to the designated position when the position change operation is performed, and the time information corresponding to the current playback position matches each other when the synchronization recovery operation is performed. To be adjusted. As a result, the operability during reproduction is improved, and synchronization between contents is ensured when necessary.

  A content playback apparatus according to the invention of claim 2 is dependent on claim 1, and includes a speed changing means (S99) for changing the playback speed of each of the plurality of contents to a designated speed when a speed change operation is accepted, and an adjusting means. In relation to the adjustment operation, setting means (S107) is further provided for setting the playback speed of each of the plurality of contents to the reference speed.

  The playback speed of each of the plurality of contents is changed to a designated speed when a speed change operation is performed, and returned to the reference speed when the playback position is adjusted. This further improves operability and ensures synchronization.

  The content playback apparatus according to the invention of claim 3 is dependent on claim 1 or 2, and the specifying means for specifying, from among the plurality of contents, the preceding content that precedes the time indicated by the time information corresponding to the playback position (S101). ), And the adjustment means performs an adjustment operation based on time information detected from the preceding content. This allows efficient viewing.

  A content reproduction apparatus according to a fourth aspect of the present invention is dependent on any one of the first to third aspects, and the plurality of contents are a plurality of video contents photographed in parallel by a plurality of cameras.

  The content playback apparatus according to the invention of claim 5 is dependent on claim 4, wherein each of the plurality of video contents is in accordance with MPEG (Moving Picture Experts Group) system, and the time information is PTS (Presentation Time Stamp).

  A content reproduction program according to a sixth aspect of the invention is a content reproduction program executed by a processor of a content reproduction apparatus that reproduces a plurality of contents each having repeatedly described time information in parallel, and performs a position change operation. A position changing step (S97) for changing the reproduction position of each of the plurality of contents to a designated position when received, a detection step (S131 to S135) for repeatedly detecting time information corresponding to the current reproduction position from each of the plurality of contents; And an adjustment step (S103, 105) that adjusts the reproduction position of each of the plurality of contents so that the times indicated by the time information detected by the detection step coincide with each other when a synchronization recovery operation is received after the change operation of the position change step. , S109).

  According to the present invention, the operability at the time of reproduction can be improved and the contents can be accurately synchronized.

  The above object, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

  Referring to FIG. 1, the hard disk video recorder 10 of this embodiment includes four video input terminals 12a to 12d. Composite video signals output from four surveillance cameras (not shown) are input to the video input terminals 12a to 12d, respectively. The input composite video signals are supplied to NTSC decoders 14a to 14d, respectively. Each of the NTSC decoders 14a to 14d decodes a given composite video signal and outputs video data.

  The video data output from the NTSC decoders 14a to 14d is supplied to the MPEG encoders 16a to 16d forming the recording circuit 42, respectively. Each of the MPEG encoders 16a to 16d performs encoding processing according to the MPEG system on the given video data and outputs a video PES (Packetized Elementary Stream).

  The video PES output from the MPEG encoders 16 a to 16 d is written in the encoder buffer 18. The controller 20 multiplexes the written video PES for each channel to generate MPEG-PS. That is, the video PES output from the MPEG encoder 16a is multiplexed to generate an MPEG-PS for CH1, the video PES output from the MPEG encoder 16b is multiplexed to generate an MPEG-PS for CH2, and the MPEG encoder 16c The output video PES is multiplexed to generate CH3 MPEG-PS, and the video PES output from the MPEG encoder 16d is multiplexed to generate CH4 MPEG-PS.

  The controller 20 also generates INDEX data for managing the video frames forming the generated MPEG-PS for each channel. Therefore, MPEG-PS and INDEX data are generated for each of CH1 to CH4. The generated MPEG-PS and INDEX data are given to an HDD (Hard Disk Drive) 44 via the encoder buffer 18.

  The HDD 44 has a built-in hard disk 22. The HDD 44 writes the given MPEG-PS and INDEX data to an MPEG file and an INDEX file formed on the hard disk 22 for each channel. Therefore, writing is performed on four MPEG files and four INDEX files in parallel.

  In writing to each channel, INDEX data always has priority over MPEG-PS. That is, for example, in writing CH1, INDEX data corresponding to 10 seconds is first written to the INDEX file, and then MPEG-PS corresponding to the 10 seconds is written to the MPEG file. The same applies to CH2 to CH4. The video captured by each of the four surveillance cameras is thus recorded on the hard disk 22 in the form of an MPEG file and an INDEX file. The recorded video may be accompanied by audio. In this embodiment, MPEG-PS and INDEX data are collectively defined as “content”. Also, by resetting the MPEG encoders 16a to 16d and the MPEG decoders 28a to 28d at the same time and simultaneously starting / stopping recording for four channels, synchronization of CH1 to CH4 is ensured, that is, the same or sufficiently close to the MPEG encoders 16a to 16d. It is assumed that the PTS value to be output is output.

  Here, referring to FIG. 2, the recording area of hard disk 22 is divided into a management area 22a, an MPEG area 22b, and an INDEX area 22c. In the management area 22a, a management file including management data for each channel (see FIGS. 3A to 3D; described later) is recorded. The MPEG area 22a includes MPEG files # 1-1, MPEG files # 1-2,... Each including CH1 MPEG-PS (see FIG. 4A; described later), and CH2 MPEG-PS respectively. MPEG file # 3-1, MPEG file # 2-2,..., MPEG file # 3-1, MPEG file # 3-2,. File # 4-1, MPEG file # 4-2,... Are recorded.

  The INDEX area 22c includes INDEX file # 1-1, INDEX file # 1-2,... Each including CH1 INDEX data (see FIG. 4B), and INDEX file # including CH2 INDEX data. , INDEX file # 2-2,..., INDEX file # 3-1, INDEX file # 3-2,... Each including INDEX data of CH3, and INDEX file # 4- each including INDEX data of CH4. 1, INDEX file # 4-2,... Are recorded.

  Note that an MPEG file and an INDEX file assigned the same identifier correspond to each other, and therefore, for example, INDEX data corresponding to MPEG-PS written in MPEG file # 1-1 is INDEX file # 1-1. Exists within.

  3A to 3D, each management data of CH1 to CH4 includes a start time, an end time, a file number, an MPEG file start position, and an INDEX file start position. “Start time” indicates the time when writing to the corresponding MPEG file is started. “End time” indicates the time when writing to the corresponding MPEG file is completed. “File number” indicates the file number of the corresponding MPEG file. “MPEG file start position” indicates the write start position of the corresponding MPEG file. “INDEX file start position” indicates the write start position of the corresponding INDEX file.

  Referring to FIG. 4A, MPEG-PS is formed by a plurality of packs, and each pack includes a pack header, a system header, and a plurality of PES packets. In the MPEG format, three types of I picture, B picture, and P picture are defined, and PES packets forming one picture do not straddle different packs. An I picture is created, for example, every 15 frames, and one GOP (Group Of Pictures) is formed by 15 frames starting from the I picture. The composite video signal output from the surveillance camera has a frame rate of 30 fps, so 15 frames forming 1 GOP correspond to 0.5 seconds.

  An SCR (System Clock Reference), a multiplexing rate, and the like are described in the pack header, and a bit rate and the like are described in the system header. Each of the plurality of PES packets includes a PES packet header and an elementary stream. The PTS indicating the presentation timing of each frame is described in the PES packet header.

  Referring to FIG. 4B, the INDEX data is divided every 24 bytes, and the divided 24 bytes are assigned to each frame. That is, 24-byte INDEX data and one frame are associated with each other. The 24 bytes are a frame size indicating the size of the corresponding frame, an offset indicating the distance of the corresponding frame from the beginning of the MPEG file, a frame type indicating the type of the corresponding frame, and time information indicating the time when the corresponding frame was created. , And the corresponding frame PTS.

  4 bytes are assigned to the frame size, 8 bytes are assigned to the offset, and 4 bytes are assigned to the frame type. Also, 4 bytes are assigned to the time information, and 4 bytes are assigned to the PTS.

  By referring to the management data and the INDEX data, it is possible to specify an MPEG file including a video recorded at a designated location, that is, a desired time, and further specify a desired frame from the MPEG file.

  Referring again to FIG. 1, the reproduction of the video recorded on the hard disk 22 is also executed in parallel for four channels. When a desired time is designated by the designated location reproduction operation, first, an MPEG file including the designated time and an INDEX file corresponding thereto are specified based on the management data of CH1 (see FIG. 3A). The Next, a frame corresponding to the specified time is specified based on the INDEX data included in the specified INDEX file. Then, the reproduction start position of CH1 is detected based on the start position of the specified MPEG file and the specified frame offset. The reproduction start position is similarly detected for CH2 to CH4.

  The HDD 44 reproduces the MPEG-PS from the detected reproduction start position for each channel. The reproduced MPEG-PS is written into the decoder buffer 26 that forms the reproduction circuit 46. The controller 24 extracts video PES from the written MPEG-PS of CH1 to CH4, respectively, and supplies the extracted video PES to the corresponding MPEG decoders 28a to 28d.

  Each of the MPEG decoders 28 a to 28 d decodes the supplied video PES to generate video data, and supplies the generated video data to the multiplexer 30. The multiplexer 30 multiplexes the given video data of CH1 to CH4. The multiplexed video data is given to the NTSC encoder 32. The NTSC encoder 32 converts the given video data into a composite video signal, and outputs the converted composite video signal to the monitor 34. As a result, four scenes captured by the four surveillance cameras are displayed in one screen.

  Thus, the four scene images displayed on one screen are taken at the same time. That is, in the designated portion reproduction, the images of CH1 to CH4 are reproduced in a state of being synchronized with each other. In this state, when a fast-forward operation or a jump operation is performed toward a specific channel via the operation panel 36, processing for changing the reproduction speed or reproduction position of that channel is performed. As a result of such individual change processing, the synchronization between CH1 to CH4 is lost.

  When the synchronization recovery operation is performed via the operation panel 36 after the synchronization is lost, the playback speed of CH1 to CH4 is reset and the channel with the highest playback position among CH1 to CH4 (hereinafter referred to as “first channel”). ) Is detected, and the reproduction position of the remaining channel is matched with that of the earliest channel. Hereinafter, this synchronization recovery processing will be described with reference to FIGS. 5, 6 </ b> A to 6 </ b> C, 7 </ b> A to 7 </ b> D, and 8 </ b> A to 8 </ b> D.

  As described above, the MPEG decoders 28a to 28d refer to the PTS when reproducing the MPEG-PS. The CPU 38 takes in the PTS when it is detected from the MPEG-PS by the MPEG decoders 28a to 28d.

  A register R (see FIG. 5) is formed in the flash memory 40, and the PTSs fetched from the MPEG decoders 28a to 28d are written in the CH1 to CH4 areas in the register R, respectively. The written PTS is overwritten by the newly captured PTS. In this way, the register R always holds the latest PTS of each channel.

  As a result of the designated portion reproduction operation, the individual change operation, and the synchronization recovery operation, the four PTSs in the register R change as shown in FIGS. 6A to 6C. Immediately after the designated portion reproduction operation is performed, as shown in FIG. 6A, the PTSs of the respective channels are substantially at the same position on the time axis. After this, if no operation is performed, the PTS of each channel proceeds on the time axis at a constant speed while maintaining this positional relationship. When an individual change operation, such as a fast-forward operation or a jump operation, is performed toward CH2, as shown in FIG. 6B, the PTS of CH2 comes into a state preceding other PTSs. The synchronization recovery operation is performed in this state.

  In response to the synchronization recovery operation, the CPU 38 compares the four PTSs in the register R with each other and obtains the earliest PTS from the register R. Next, the offset corresponding to the acquired PTS or the closest offset is extracted from the INDEX data (see FIG. 4B). Then, the controller 24 is instructed to clear the decoder buffer 26 and output the MPEG-PS of each channel from the position corresponding to the extraction offset at a single speed.

  The controller 24 executes such an instruction, and as a result, the PTSs of CH1, CH3, and CH4 in the register R catch up with the PTS of the preceding CH2, as shown in FIG. After this, if no operation is performed, the PTS of each channel proceeds on the time axis at a constant speed while maintaining the positional relationship with each other.

  As a result of the designated location reproduction operation, individual change operation, and synchronization recovery operation, the four scenes in the screen change as shown in FIGS. 7A to 7D or FIGS. 8A to 8D. . When the designated location playback operation is performed, as shown in FIG. 7A or FIG. 8A, the playback of all four scenes starts at the same speed (10:10:00) at the same speed. .

  Thereafter, when a fast forward operation toward CH2 is performed as an individual change operation, the playback speed of CH2 is changed to, for example, double speed as shown in FIG. 7B, and as a result, the time of the scene corresponding to CH2 is changed. It becomes a state preceding that of other scenes. The difference in time increases with the passage of time. When the synchronization recovery operation is performed when the time difference reaches 50 seconds, for example, as shown in FIGS. 7C and 7D, the reproduction speed of CH2 is changed to 1 × speed, and CH1, CH3, and The time of each CH4 is moved forward by 50 seconds. As a result, the time and playback speed match in the four scenes.

  On the other hand, when a jump operation toward CH2 is performed as an individual operation, as shown in FIG. 8B, the time of the scene corresponding to CH2 moves to a breath forward, for example, 4 minutes and 40 seconds. In this case, the difference between the time of the scene corresponding to CH2 and that of the other scene is kept at 4 minutes 40 seconds. When the synchronization recovery operation is performed, as shown in FIGS. 8C and 8D, the times of CH1, CH3, and CH4 are moved forward by 4 minutes and 40 seconds. As a result, the time and playback speed match in the four scenes.

  In the hard disk video recorder 10 of this embodiment, recording is performed even when the normal recording operation is not performed by the operator. Such a recording operation is defined as “temporary recording”. At this time, the MPEG-PS of CH1 to CH4 is cyclically written in the MPEG file for temporary recording of CH1 to CH4.

  Further, when the designated portion reproduction operation by the operator is not performed, the MPEG-PS recorded on the hard disk 22 is reproduced promptly. That is, the same MPEG-PS recording / reproduction is performed almost simultaneously. Such playback operation is defined as “live playback”. When the designated part reproduction operation is performed, the live reproduction is interrupted, and the MPEG-PS at the designated part is reproduced from the hard disk 22. Note that the above-described temporary recording or normal recording is performed even while the designated portion reproduction operation is performed.

  The amount of data that can be recorded in one MPEG file is limited to 1 Gbyte or less. When the designated MPEG file is full in each of CH1 to CH4, the HDD 44 designates the next MPEG file and INDEX file as new recording destinations. Subsequent MPEG-PS and INDEX data are recorded in the newly designated MPEG file and INDEX file, respectively. The operation of updating the recording destination file in this way is defined as “file straddling”.

  Such file straddling also occurs during playback. That is, when all the MPEG-PSs are reproduced from the designated MPEG file, the next MPEG file is designated as the reproduction destination, and the MPEG-PS is reproduced from the designated MPEG file.

  Under the control of a multitasking OS such as μITRON, the CPU 38 performs the main task shown in FIG. 9, the normal recording task shown in FIGS. 10 and 11, the designated portion reproduction task shown in FIGS. 12 and 13, and the FIG. The indicated PTS capture task is executed in parallel. Note that control programs corresponding to these tasks are stored in the flash memory 40.

  First, the main task will be described. Referring to FIG. 9, in steps S1 and S3, a normal recording task and a designated portion reproduction task are activated, respectively, in step S5, MPEG encoders 16a to 16d and MPEG decoders 28a to 28d are activated, and in step S7, for temporary recording. The HDD 44 is instructed to open the four MPEG files. In step S9, the HDD 44 is instructed to start temporary recording, and in step S11, the HDD 44 is instructed to start live playback. As a result, the temporarily recorded video and audio are output almost simultaneously with the recording.

  When temporary recording and live playback are started, it is determined whether or not a normal recording start command is issued in step S13, and whether or not a normal recording stop command is issued is determined in step S15, and a specified location playback start command is issued. Is determined in step S25, and it is determined in step S27 whether or not a designated portion reproduction stop command has been issued.

  When a normal recording start operation is performed by the operation panel 36, a normal recording start command is issued. When a normal recording stop operation is performed by the operation panel 36, a normal recording stop command is issued. In addition, when a designated portion reproduction start operation is performed by the operation panel 36, a designated portion reproduction start command is issued. When a designated portion reproduction stop operation is performed by the operation panel 36, a designated portion reproduction stop command is issued.

  If YES is determined in the step S13, the HDD 44 is instructed to stop temporary recording in a step S17, and the HDD 44 is instructed to close four MPEG files for temporary recording in a step S19.

  If YES is determined in the step S15, the HDD 44 is instructed to open four MPEG files for temporary recording in a step S21, and the HDD 44 is instructed to start temporary recording in a step S23.

  If YES is determined in the step S25, the HDD 44 is instructed to stop the live reproduction in a step S29. If YES is determined in the step S27, the HDD 44 is instructed to start live reproduction in a step S31.

  Next, the normal recording task will be described. Referring to FIG. 10, it is determined in step S41 whether or not a normal recording start command has been issued. If YES, the management file, the four MPEG files, and the four INDEX files are opened in HDD 44 in step S43. To order. When the file is opened, the HDD 44 is instructed to start normal recording in step S45.

  In subsequent step S47, for each of CH1 to CH4, the HDD 44 is instructed to write the recording start time start_time, the file number fnum, the MPEG file start position Mstart, and the INDEX file start position Istart to the management file.

  In step S49, it is determined whether or not a normal recording stop command has been issued. In step S51, it is determined whether or not file straddling has occurred, that is, whether or not the writing destination MPEG file has become full. If “YES” in the step S49, the HDD 44 is instructed to stop the normal recording in a step S53, and the HDD 44 is instructed to add the recording end time end_time to the management file for each of the CH1 to CH4 in a step S55. In step S57, the HDD 44 is instructed to close the MPEG file, INDEX file, and management file, and then the process returns to step S41.

  If YES in step S51, steps S59 to S67 are executed. Referring to FIG. 11, in step S59, the HDD 44 is instructed to add the end time end_time to the management file for the channel where the file crossing has occurred. In step S61, the HDD 44 is instructed to close the MPEG file for the channel where the file straddling has occurred. In step S63, the HDD 44 is instructed to open the next MPEG file for the channel where the file straddle has occurred, and in step S65, the HDD 44 is instructed to start recording from the top of the opened MPEG file. In step S67, the HDD 44 is instructed to write the recording start time start_time, the file number fnum, the MPEG file start position Mstart, and the INDEX file start position Istart to the management file for the channel where the file crossing has occurred. When the writing is completed, the process returns to step S49.

  Next, the designated place reproduction task will be described. Referring to FIG. 12, first, at step S81, it is determined whether or not a designated location reproduction start command has been issued. If YES, an MPEG file including the designated location and corresponding to each of CH1 to CH4 at step S83. The HDD 44 is instructed to open the INDEX file. The file numbers of the MPEG file and the INDEX file to be opened are specified by referring to the management data (FIGS. 3A to 3D) in the management file. The specified four file numbers are described in the command.

  In step S85, four PTS import tasks (see FIG. 14) corresponding to CH1 to CH4, respectively, are activated. In step S87, for each of CH1 to CH4, the HDD 44 is instructed to start playback from a specific frame of MPEG-PS in the opened MPEG file. The frame to be played back is specified by referring to the INDEX data in the opened INDEX file. The instruction describes the offset of the specified frame.

  Thereafter, the process enters a loop of steps S89, S91, S111 and S113. In step S89, it is determined whether an individual change command has been issued. In step S91, it is determined whether a synchronization recovery command has been issued. Turning to FIG. 13, it is determined in step S111 whether or not file straddling has occurred, and in step S113, it is determined whether or not a designated location playback stop command has been issued.

  Returning to FIG. 12, if “YES” in the step S89, it is determined whether or not the individual change command is a speed change in a step S93, and whether or not the individual change command is a speed change is determined in a step S95. If “YES” in the step S93, the process proceeds to a step S99 to change the reproduction speed of the target channel. If “NO” in the step S95, the process shifts to a step S97 to change the reproduction position of the target channel. After the change, return to the loop.

  If YES in step S91, steps S101 to S109 are executed. That is, in step S101, the four PTSs in the register R are compared with each other, and the earliest PTS is specified based on the comparison result. In step S103, the specified PTS is acquired from the register R. In step S105, for each of CH1 to CH4, the offset corresponding to the acquired PTS or the closest offset is extracted from the INDEX data included in the opened INDEX file.

  In step S107, the reproduction speed is reset to 1 × for each of CH1 to CH4. In step S109, the reproduction position is reset to a position corresponding to the extracted offset for each of CH1 to CH4. As a result of the resetting, the synchronization of the four MPEG-PSs corresponding to CH1 to CH4 is restored (see FIGS. 6B and 6C). After this, return to the loop.

  Referring to FIG. 13, if “YES” in the step S111, the process shifts to a step S115 to instruct the HDD 44 to open the next MPEG file for the channel where the file straddling has occurred. In the subsequent step S117, the HDD 44 is instructed to start reproduction from the top of the opened MPEG file. In step S119, the HDD 44 is instructed to close the reproduced MPEG file. After this, return to the loop.

  If “YES” in the step S113, the process shifts to a step S115 to instruct the HDD 44 to stop the reproduction. In step S113, the HDD 44 is instructed to close the MPEG file and the INDEX file, and in step S125, the PTS import task is terminated. Then, this task itself is finished.

  Next, the PTS import task will be described. Referring to FIG. 14, in the PTS import task for CH1, first, in step S131, it is determined whether or not the MPEG decoder 28a has detected PTS. If YES, the process proceeds to step S113, and the detected PTS is detected. Captured from the MPEG decoder 28a. In the subsequent step S115, the fetched PTS is written in the CH1 area of the register R (see FIG. 5). After writing, the process returns to step S131. Note that the same processing is performed in the PTS import task for CH2 to CH4.

  As can be seen from the above description, in this embodiment, the HDD 44 reproduces four MPEG-PS recorded on the hard disk 22 in parallel. When receiving the position change operation, the CPU 38 changes the reproduction position of each of the four MPEG-PSs to the designated position (S97).

  On the other hand, the CPU 38 repeatedly detects the PTS corresponding to the current reproduction position from each of the four contents through the MPEG decoders 28a to 28d (S131 to S135). When the synchronization recovery operation is accepted, the reproduction positions of the four MPEG-PSs are adjusted so that the times indicated by the detected PTSs coincide with each other (S103, S105, S109).

  That is, the playback positions of each of the plurality of MPEG-PSs are changed to the designated positions when the position change operation is performed, while the PTSs corresponding to the current playback position match when the synchronization recovery operation is performed. To be adjusted. As a result, the operability during reproduction is improved, and synchronization between contents is ensured when necessary.

  Further, when receiving the speed change operation, the CPU 38 changes the playback speed of each of the plurality of MPEG-PSs to the designated speed (S99). Then, along with the adjustment of the playback position, the playback speed of each of the plurality of contents is reset to the reference speed (S107). That is, the playback speed of each of the plurality of contents is changed to the designated speed when the speed changing operation is performed, and returned to the reference speed when the playback position is adjusted. This further improves operability and ensures synchronization.

  The CPU 38 identifies the MPEG-PS with the earliest timing indicated by the PTS corresponding to the reproduction position from among the plurality of MPEG-PS (S101). Then, the playback position is adjusted based on the PTS detected from the specified MPEG-PS. This allows efficient viewing.

  In this embodiment, the playback position is adjusted based on the PTS detected from the most preceding MPEG-PS. However, even if this is performed based on the PTS detected from the most backward MPEG-PS. Good. This allows for careful viewing with few oversights. Further, it may be possible to arbitrarily select which MPEG-PS is used for adjustment based on the detected PTS. Thereby, appreciation suitable for the situation can be performed. Alternatively, instead of adjusting the playback position based on any one PTS, the reference time may be calculated based on a plurality of PTSs, and the playback position may be adjusted according to the calculation result.

  The hard disk video recorder 10 has been described above, but the present invention can be applied to a content playback apparatus that plays back a plurality of contents each having time information that is repeatedly described.

It is a block diagram which shows one Example of this invention. It is an illustration figure which shows the mapping state of the hard disk applied to the FIG. 1 Example. (A) is an illustrative view showing an example of CH1 management data created in the embodiment of FIG. 1, and (B) is an illustrative view showing an example of CH2 management data created in the embodiment of FIG. ) Is an illustrative view showing one example of CH3 management data created in FIG. 1 embodiment, and (D) is an illustrative view showing one example of CH4 management data created in FIG. 1 embodiment. (A) is an illustrative view showing a structure of MPEG-PS created in the embodiment of FIG. 1, and (B) is an illustrative view showing a structure of INDEX data created in the embodiment of FIG. FIG. 3 is an illustrative view showing a configuration example of a register applied to the embodiment in FIG. 1; (A)-(C) is an illustration figure which shows the change of the positional relationship of four PTS hold | maintained at the register | resistor of FIG. (A)-(D) is an illustration figure which shows an example of the change of the screen displayed in FIG. 1 Example. (A)-(D) is an illustration figure which shows another example of the change of the screen displayed in FIG. 1 Example. It is a flowchart which shows a part of operation | movement of FIG. 1 Example. It is a flowchart which shows a part of other operation | movement of FIG. 1 Example. It is a flowchart which shows a part of other operation | movement of FIG. 1 Example. It is a flowchart which shows a part of operation | movement of FIG. 1 Example further. It is a flowchart which shows a part of other operation | movement of FIG. 1 Example. It is a flowchart which shows a part of other operation | movement of FIG. 1 Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Hard disk video recorder 16a-16d ... MPEG encoder 18 ... Encoder buffer 20, 24 ... Controller 22 ... Hard disk 26 ... Decoder buffer 28a-28d ... MPEG decoder 30 ... Multiplexer 34 ... Monitor 38 ... CPU
42 ... Recording circuit 44 ... Hard disk drive (HDD)
46. Reproduction circuit

Claims (6)

In a content reproduction apparatus for reproducing a plurality of contents each having time information repeatedly described in parallel,
Position changing means for changing the reproduction position of each of the plurality of contents to a designated position when a position changing operation is received;
Detection means for repeatedly detecting time information corresponding to the current reproduction position from each of the plurality of contents, and time information detected by the detection means when a synchronization recovery operation is received after a change operation of the position change means An apparatus for reproducing content, comprising adjusting means for adjusting a reproduction position of each of the plurality of contents so that times coincide with each other. A speed changing means for changing the playback speed of each of the plurality of contents to a designated speed when a speed change operation is received; and a playback speed of each of the plurality of contents is set to a reference speed in connection with the adjustment operation of the adjusting means. The content reproduction apparatus according to claim 1, further comprising setting means for setting. Further comprising specifying means for specifying, from among the plurality of contents, preceding contents whose time indicated by the time information corresponding to the reproduction position is most advanced,
The content reproduction apparatus according to claim 1, wherein the adjustment unit performs an adjustment operation based on time information detected from the preceding content.   The content reproduction apparatus according to any one of claims 1 to 3, wherein the plurality of contents are a plurality of video contents photographed in parallel by a plurality of cameras. Each of the plurality of video contents follows the MPEG system,
The content reproduction apparatus according to claim 4, wherein the time information is PTS. A content reproduction program that is executed by a processor of a content reproduction apparatus that reproduces a plurality of contents each having repeatedly described time information in parallel,
A position changing step for changing the playback position of each of the plurality of contents to a designated position when a position changing operation is received;
A detection step that repeatedly detects time information corresponding to the current reproduction position from each of the plurality of contents, and time information detected by the detection step when a synchronization recovery operation is received after the change operation of the position change step A content playback program comprising an adjusting step of adjusting the playback position of each of the plurality of contents so that the times coincide with each other.

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