JP4748977B2 - Portable viewing device - Google Patents

Description

  The present invention relates to a portable viewing device such as a cellular phone capable of viewing terrestrial digital broadcasting.

In recent years, a mobile device such as a mobile phone having a TV broadcast viewing function and a recording function has been proposed (see Patent Document 1). Furthermore, digital terrestrial broadcasting (one segment broadcasting) is scheduled for portable viewing devices.
JP 2003-101921 A

  By the way, when performing broadcast viewing and recording in a portable viewing device, it is expected that there may be cases where the broadcast cannot be viewed or recorded to the end due to the relationship with the battery and memory. In addition, if much of the CPU processing capacity is used for decoding, other processing may not be performed smoothly.

  In view of the above circumstances, an object of the present invention is to provide a portable viewing device that can record a program to the end as much as possible and can reduce the processing load due to decoding. .

  In order to solve the above problems, the portable viewing device of the present invention has a driving battery, demodulates the received digital broadcast wave, generates a stream, generates a frame from the stream, and decodes the frame In the portable viewing device configured to perform the normal viewing mode for decoding for viewing all of the independent frame that can be decoded by itself and the accompanying frame group that can be decoded in consideration of the independent frame; It was configured to be able to execute the intermittent viewing mode in which the original frame is decoded but part or all of the associated frame group is not decoded (the ratio of the unaccompanied associated frame to the entire associated frame group is referred to as the intermittent ratio). (Hereinafter referred to as the first configuration in this section).

  With the above configuration, when the intermittent viewing mode is selected, the original frame is decoded, but a part or all of the accompanying frame group is not decoded. be able to. In particular, when another CPU performs the decoding process, it is possible to reduce battery consumption by cutting off the power supply to the other CPU during the non-decoding period. In addition, as described above, by not performing partial decoding, there is a case where a fast-moving video is easy to see.

  In the portable viewing device of the first configuration, the intermittent ratio is preferably set so as to increase as the remaining battery level decreases.

  In the portable viewing device of the first configuration, the intermittent ratio is determined by a table in which priority indicating which of image quality input by a user and viewing time is prioritized and a remaining battery level are associated with each other. Also good.

  In the first configuration and the configuration subordinate thereto, the intermittent ratio may be reset under a predetermined condition.

  In the first configuration and the subordinate configuration, the intermittent viewing mode may be configured to be able to perform settings that omit generation of either video or audio.

  In the first configuration and the configuration subordinate thereto, the normal viewing mode and the intermittent viewing mode may be selected by the user. In such a configuration, even when the intermittent viewing mode is selected by the user, the normal viewing mode may be executed under a predetermined condition.

  The portable viewing device of the present invention is a portable viewing device having a drive battery and configured to reproduce a stream from a recording medium to generate a frame or to reproduce a frame from a recording medium. A normal playback viewing mode that decodes all of the independent frame that can be decoded by itself and the accompanying frame group that can be decoded in consideration of the independent frame for playback viewing, and the original frame is decoded, but the associated frame group It is configured to be able to execute an intermittent playback viewing mode in which part or all of the decoding is not performed (the ratio of the accompanying frames that are not decoded to the entire accompanying frames is referred to as an intermittent ratio) (hereinafter referred to as this section). This is called the fourth configuration.)

  With the above configuration, when the intermittent playback viewing mode is selected, the original frame is decoded, but a part or all of the accompanying frame group is not decoded. can do. In particular, when another CPU performs the decoding process, it is possible to reduce battery consumption by cutting off the power supply to the other CPU during the non-decoding period. In addition, as described above, by not performing partial decoding, there is a case where a fast-moving video is easy to see.

  In the portable viewing device having the fourth configuration, it is preferable that the intermittent ratio is set to increase as the remaining battery level decreases.

  In the portable viewing device of the fourth configuration, the intermittent ratio is determined by a table in which priority indicating which of image quality and viewing time input by a user is prioritized and a remaining battery level are associated with each other. May be.

  In the fourth configuration and the configuration dependent thereon, the intermittent ratio may be reset under a predetermined condition.

  In the fourth configuration and the subordinate configuration, in the intermittent playback viewing mode, a setting may be made so as to omit generation of either video or audio.

  In the fourth configuration and the configuration subordinate thereto, the normal playback viewing mode and the intermittent playback viewing mode may be selected by the user. In such a configuration, even when the intermittent playback viewing mode is selected by the user, the normal playback viewing mode may be executed under a predetermined condition.

  As described above, according to the present invention, it is possible to record a program to the end as much as possible, and to achieve various effects such as reducing the processing load due to decoding.

  Hereinafter, a portable viewing device according to an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a block diagram showing a mobile phone 100 with a TV as a portable viewing device. The TV-equipped mobile phone 100 includes a terrestrial digital broadcast receiver. In this broadcast receiving unit, the terrestrial antenna 1 gives the received signal to the terrestrial digital tuner 2. The terrestrial digital tuner 2 extracts a signal having a specific frequency from the high-frequency digital modulation signal including video / audio data. The terrestrial digital tuner 2 includes a demodulation circuit, a deinterleave circuit, an error correction circuit, and the like, and demodulates the selected digital modulation signal to output a transport stream (TS).

  The demultiplexer (DEMUX) 3 converts the transport stream (TS) shown in FIG. H.264 and other video frames, audio frames, and sections. The section includes PSI / SI (Program Specific Information / Service Information), broadcast information (region identifier, service type, broadcast station identification, service number, remote control key ID) and the like. The video frame and the audio frame are supplied to the AV decoder 4, and the section is supplied to the section processing unit 5. The section processing unit 5 performs EPG (electronic program guide) data creation processing based on the PSI / SI included in the section.

  The AV decoder 4 includes a video decoder that decodes video frames and an audio decoder that decodes audio frames. The video decoder decodes an input encoded signal to obtain a quantization coefficient and a motion vector, and performs inverse DCT transform, motion compensation control based on the motion vector, and the like. The audio decoder decodes the input encoded signal to generate audio data. The video data generated by the decoding is output to the video processing circuit 5, and the audio data is output to the audio processing circuit 6.

  The video processing circuit 6 receives video data from the AV decoder 4 and generates, for example, RGB data. The RGB data is given to a display unit (for example, a liquid crystal display panel) 8 to display an image. The audio processing circuit 7 receives the audio data output from the AV decoder 4 and performs D / A conversion to generate, for example, a right (R) sound analog signal and a left (L) sound analog signal. These audio signals are supplied to a speaker 9 or a speaker (not shown) provided separately from the speaker 9.

  At the time of recording the received digital broadcast program, for example, video frames and audio frames are input to the recording processing unit 10 (may be TS recording). The recording processing unit 10 converts the video frame and the audio frame into a recording format. The file system 11 records the formatted file data in a memory (an internal memory, a removable memory card, etc.) 12. On the other hand, at the time of reproduction, file data to be reproduced is read from the memory 12 by the file system 11 and supplied to the recording processing unit 10. The video frame and the audio frame generated by the recording processing unit 10 are supplied to the AV decoder 4 and thereby played back.

  The memory management unit 14 generates remaining memory information of the memory 12 and gives this remaining memory information to the CPU 13. The memory remaining amount may be a percentage of the remaining amount (memory free capacity) with respect to the total memory amount, or may be usable byte amount information. When the CPU 13 has data “120” as the recordable time when the memory is completely empty and receives information such as 50% as the percentage, the CPU 13 determines that the recordable time is 60 minutes. Also, for example, when there is unit byte amount information used in video recording for one second, the recordable time (seconds) is calculated by dividing the usable byte amount by the unit byte amount. Can do. Of course, the above processing example is an example.

  The time management unit 15 gives the current time information to the CPU 13. Further, the CPU 13 can acquire the program start time and program duration information of the program from the section processing unit 5 when viewing (recording) the program. When viewing (recording) is started in the middle of a program, the viewing (recording) time can be calculated by obtaining a value obtained by subtracting the program start time from the current time and subtracting this value from the program duration information.

  The operation unit 16 includes a numeric keypad, a cross key (arrow key), and various function keys in the mobile phone 100 with TV.

  The battery management unit 17 detects the remaining amount of the battery (secondary battery, primary battery) 18 and gives this remaining amount information to the CPU 13. The remaining battery level is used not only for displaying a pictogram indicating the remaining battery level (for example, smallly displayed on the upper portion of the display unit 8), but also used for intermittent viewing (recording) control according to the present invention. When the CPU 13 has data “120” as the viewable (recording) possible time when the remaining battery level is 100% and receives information such as 50% as the remaining battery level from the battery management unit 17, Recording) It is determined that the possible time is 60 minutes. Of course, the above processing example is an example.

  The telephone function unit 20 performs communication control and call processing for a mobile phone.

Here, the concept of the basic processing of the present invention is shown below.
I. If it is desired to record the received program to the end, the power consumption of the battery 18 is reduced because it may be small.
B. If it is desired to record the received program to the end, the usage amount of the memory 12 is reduced.
C. If it is desired to watch the received program to the end, the power consumption of the battery 18 is reduced because it may be small.
D. By detecting the remaining amount of the battery 18 and the remaining amount of the memory 12, and comparing the viewing (recording) possible time and the viewing (recording) end time based on the detected values, an optimal intermittent ratio (intermittent interval) is obtained. decide.
E. The intermittent processing is realized, for example, by generating a smaller number of frames than the number of frames during normal viewing / recording.

[Setting process]
Settings for intermittent viewing / recording processing can be performed, for example, by calling a menu screen in a standby state, selecting an item on the menu screen, and inputting a value by the user. FIG. 2 shows a flowchart for setting. When the user selects the intermittent function on the menu screen (YES in step S1), for example, a time input frame screen is displayed as the next screen. The user inputs viewing or recording end time on this screen (YES in step S2, step S3). When the time input is skipped, the program information (EPG information) is used to calculate the time until the end of the program (NO in step S2). Next, a priority input screen is displayed as the next screen. This priority is used for calculating the intermittent ratio when there is no end time by user input and the end time cannot be obtained from the program information. For example, as shown on the vertical axis of the table in FIG. 8, the smaller the numerical value, the higher the priority is given to the image quality, and the higher the numerical value, the higher priority is given to time, and the user inputs a desired numerical value (priority). . Then, as shown in FIG. 8, a table in which the intermittent ratio is obtained from the priority and the remaining battery level is prepared in the memory. In addition, a table in which the intermittent ratio is obtained from the priority and the remaining memory capacity in the same format is also prepared. The user inputs a priority (numerical value) in viewing or recording on the input screen (step S4).

[Determination of intermittent ratio during viewing]
At the start of TV viewing, the CPU 13 performs a process of confirming whether or not the section management unit (EPG management unit) 6 has the program information of the program being received. Further, the CPU 13 acquires battery remaining amount information from the battery management unit 17.

  When the program information of the program being received exists, the CPU 13 calculates the viewable time from the battery remaining amount information, and compares the time until the end of the currently received program obtained from the program information and the viewable time. And process as follows.

I. When viewable time ≧ program end time, the viewing process in the normal mode is performed without intermittent.
B. When viewable time <program end time, the number of frames to be decoded is determined at a ratio of (viewable time / program end time) × 100% or (viewable time / program end time) × 100% ± α. . Note that the ratio of the undecoded accompanying frames to all the accompanying frames is an intermittent rate. Therefore, the greater the intermittent ratio, the greater the number of accompanying frames that are not decoded. The frame generation in the intermittent viewing mode will be described later. The accompanying frame corresponds to a non_IDR frame described later.

  If the program information does not exist, the end time information input in step S3 in FIG. 2 is used. If the end time information does not exist, the priority input in step S4 in FIG. 2 is used. CPU13 determines an intermittent ratio from the table of FIG. 8 based on the priority and battery remaining charge which were input by the user.

  If the recorded program is reproduced and viewed, the reproduction time information stored in the memory 12 can be used as ancillary information of the recorded program.

[Determining intermittent ratio during recording]
At the start of recording, the CPU 13 performs processing for checking whether or not the program information of the program being received and recorded exists in the section management unit (EPG management unit) 6. Further, the CPU 13 acquires battery remaining amount information from the battery management unit 17. Further, the CPU 13 acquires remaining memory information from the memory management unit 14.

  When the program information exists, the CPU 13 compares the time until the end of the program obtained from the program information with the operable time based on the remaining battery capacity and the recordable time based on the remaining memory capacity, and processes as follows: .

I. When the operable time based on the remaining battery level ≧ the program end time and the recordable time based on the remaining memory amount ≧ the program end time, the recording process is performed in the normal mode without any intermittent operation.
B. In cases other than the above, the number of recording frames is provisionally determined at a ratio of (operable time / program end time) × 100% or (operable time / program end time) × 100% ± α. Further, the number of recording frames is provisionally determined at a ratio of (recordable time / program end time) × 100% or (recordable time / program end time) × 100% ± α. A smaller number of recording frames is adopted out of both the number of recording frames. Here, the ratio of non-recording accompanying frames to all accompanying frames is referred to as an intermittent ratio. The accompanying frame corresponds to a non_IDR frame described later.

  When the program information does not exist, the end time information input in step S3 in FIG. 2 is used. If the end time information does not exist, the priority input in step S4 in FIG. 2 is used. The CPU 13 extracts the intermittent ratio from the table of FIG. 8 based on the priority input by the user and the remaining battery level. Further, an intermittent ratio is extracted from a table (not shown) based on the priority and the remaining memory capacity. CPU13 employ | adopts the intermittent ratio with a larger value among both intermittent ratios. The intermittent ratio when recording while viewing the received program is set to be larger than the intermittent ratio when recording without viewing the received program.

  FIG. 3 is a flowchart showing the above processing contents in a simple manner. When viewing (recording) is started, the CPU 13 determines whether or not the intermittent function is ON (step S11), and when it is OFF, normal viewing (recording) is performed (step S12). When the intermittent function is ON (YES in step S11), the remaining battery level (and the remaining memory capacity) is detected (step S13). The CPU 13 determines whether an end time exists (step S14). If the end time does not exist, the intermittent rate is set based on the priority (see the table in FIG. 8) (step S15), and the process proceeds to step S17. On the other hand, if the end time exists (YES in step 14), the intermittent ratio is calculated by comparing the end time with the remaining battery level (and the remaining memory capacity) (step S16). When intermittent (0%) is not necessary (YES in step S17), normal mode viewing (recording) is performed (step S12). When intermittent is required (NO in step S17), viewing (recording) in intermittent mode is performed (step S18). Further, the CPU 13 monitors the occurrence of an interrupt (step S19). When the occurrence of an interrupt is detected, the CPU 13 performs an interrupt process (step S20). When no interrupt is detected, the viewing (recording) is terminated.

  By the way, in the terrestrial digital broadcasting, as described above, the broadcast data is composed of a transport stream (Transport Stream) made up of fixed-length data called a transport stream packet (Transport Stream Packet). Each TS packet is assigned a PID based on data such as video data and audio data, and the demultiplexer 3 separates the data based on the PID.

  In terrestrial digital broadcasting for mobile phones, the video encoding method is IEEE H.264. H.264 is adopted. H. H.264 includes an IDR frame (independent frame) and a non_IDR frame (accompanying frame). It is guaranteed that decoding can be performed normally when decoding from the IDR frame, and the IDR frame must be reliably decoded. become.

  In the intermittent processing, for example, if normal viewing / recording is performed at a rate of 15 frames per second, 3 (15-12) frames at an intermittent rate of 80%, 7 (15-8) frames at an intermittent rate of 50%, intermittent If the ratio is 40%, only 9 (15-6) frames are processed.

  In the intermittent viewing process, when only N frames (for example, 5 frames) are decoded, the IDR frame is set as the first frame, and then the N frames are decoded and displayed. When the display of N frames is completed, the video data (packet ID) is checked until the next IDR frame is detected. Specifically, as shown in the flowchart of FIG. 4, when only N frames are viewed, when the video frame is completed (step S21), it is determined whether or not it is an IDR frame (step S22). If it is an IDR frame, 0 is set in the frame counter (step S23), and the process proceeds to step S25. If it is not an IDR frame, it is determined whether or not the value of the frame counter is greater than or equal to N (step S24). If it is greater than or equal to N, the process returns to step S21. On the other hand, when the value of the frame counter is less than N (NO in step S24), decode display is performed (step S25). Further, the frame counter is incremented (step S26), and the process returns to step S21.

  In such intermittent viewing, an IDR frame and, for example, five non_IDR frames are displayed. The video of the last non_IDR frame is continuously displayed during the remaining 10 frames. Then, the display of the next IDR frame and the display of five non_IDR frames are followed. For audio, all frames are decoded.

  When frame recording is performed, the recording frame is determined by the same method as described above, and the recording frame is recorded. Specifically, as shown in the flowchart of FIG. 5, first, a video frame is completed (step S41). Next, it is determined whether the frame is an IDR frame (step S42). If the frame is an IDR frame, 0 is set in the frame counter (step S43). If it is not an IDR frame (NO in step S42), it is determined whether or not the value of the frame counter is greater than or equal to N (step S44). If the value of the frame counter is greater than or equal to N, the process returns to step S41. If the value of the frame counter does not satisfy N, recording is performed (step S45). Further, the frame counter is incremented (step S46), and the process returns to step S41. Note that the recording processing unit 10 records the intermittent rate in the memory 12 as accompanying information of the recorded program when intermittent recording is performed. At the time of reproduction, processing similar to the intermittent viewing (continuous display for omitted frames) is performed based on the intermittent ratio. Further, the number of frames omitted as the attached information of the recorded program may be recorded in the memory 12.

  When performing TS recording, as shown in the flowchart of FIG. 6, when TS packets are acquired, buffering is performed (step S51). If the TS packet is not video data (NO in step S52), the next TS packet is acquired (proceeds to step S51). If the TS packet is video data (YES in step S52), it is determined whether the video frame is completed (step S53). If the video frame is not completed, the next TS packet is acquired (proceed to step S51). When the frame is completed, it is determined whether it is an IDR frame or a non_IDR frame (step S54). If it is an IDR frame, 0 is set in the frame counter, and all TS packets are recorded from the recording start position (step S58). The counter is incremented (step S59). If it is not an IDR frame (NO in step S54), it is determined whether or not the value of the frame counter is greater than or equal to N (step S56). If the value of the frame counter is greater than or equal to N, TS packets other than the video TS packet are recorded (step S57), and the process proceeds to step S60. On the other hand, if the value of the frame counter is less than N (NO in step S56), all TS packets are recorded (step S58), the frame counter is incremented (step S59), and the process proceeds to step S60. In step S60, the recording start position is updated, and then the process returns to step S51.

  When viewing (recording) only one of video and audio, unnecessary TS packets are not acquired (discarded by filtering), so that only one of video and audio can be acquired. When video decoding is not performed, power consumption is further suppressed. For example, as shown in the flowchart of FIG. 7, TS packet acquisition is performed (step S31), and it is determined whether or not the acquired TS packet is a TS packet to be viewed (step S32). If it is a TS packet to be viewed (YES in step S32), a frame is created (step S33). Steps S32 to S34 are repeated until the frame is completed. When the frame is completed (YES in step S34), decode display is performed (step S35), and the process returns to step S31.

  When a received program or other content is recorded in the memory (built-in memory, removable memory card, etc.) 12, the above-described intermittent processing in viewing can be applied when reproducing the program. This intermittent processing may be applied only when the recorded content is recorded in the normal recording mode, and may not be applied when the recorded content is recorded in the intermittent recording mode. This reproduction process can also be used in a reproduction-only portable device (including a portable telephone with a reproduction function) that does not include a digital broadcast receiver.

  Further, when interrupt processing occurs (see, for example, step S20 in FIG. 3), the remaining battery capacity and remaining memory capacity may be detected again during or after the interrupt processing, and the intermittent ratio may be recalculated. The timing (trigger) for calculating and recalculating the intermittent ratio may be periodic, when some operation is performed by the user, or when the CPU 13 receives some event.

  In the above example, the intermittent ratio is variable. However, when the intermittent mode is selected by the user, the intermittent mode is executed in which the intermittent ratio is uniformly 50% regardless of the remaining battery level and the remaining memory capacity. You may do it. The user may select the intermittent mode to reduce the processing load on the CPU (when it feels that some processing is slow), not from the viewpoint of the remaining battery level. Further, instead of allowing the user to select between the normal mode and the intermittent mode, for example, the mode may be automatically switched to the intermittent mode when the remaining battery level or the remaining memory level drops below 50%. In the intermittent mode, the non-IDR frame may not be decoded at all. When the dedicated decoding circuit (separate CPU) is responsible for the decoding process, power consumption can be further suppressed by cutting off the power supply to the dedicated circuit during non-decoding.

It is the block diagram which showed the mobile telephone with TV of embodiment of this invention. It is the flowchart which showed the intermittent setting of embodiment of this invention. It is the flowchart which showed the intermittent process of embodiment of this invention. It is the flowchart which showed intermittent viewing-and-listening of embodiment of this invention. It is the flowchart which showed the intermittent recording (frame recording) of embodiment of this invention. It is the flowchart which showed the intermittent recording (TS recording) of embodiment of this invention. It is the flowchart which showed the intermittent process of audio / video single viewing / listening of embodiment of this invention. It is explanatory drawing which showed an example of the table for the intermittent process of embodiment of this invention. It is explanatory drawing which showed the relationship between a transport stream and a video / audio frame.

Explanation of symbols

4 AV decoder 10 Recording processing unit 12 Memory 13 CPU
14 Memory management unit 15 Time management unit 17 Battery management unit

Claims (10)

A portable viewing device having a drive battery, configured to demodulate a received digital broadcast wave to generate a stream, generate a frame from the stream, and decode the frame. Normal viewing mode for decoding for viewing all possible independent frames and associated frame groups that can be decoded in consideration of the independent frames, and decoding the original frame but not part or all of the associated frame groups It is configured to be able to execute the intermittent viewing mode (the proportion of the accompanying frames that are not decoded with respect to the entire accompanying frames group is referred to as an intermittent proportion).
When the program end time of the program received by the digital broadcast wave can be acquired, and when the viewable time by the remaining battery of the driving battery is equal to or longer than the program end time, the normal viewing mode If the viewable time is less than the program end time, the number of frames to be decoded in the intermittent view mode at an intermittent rate based on a value obtained by dividing the viewable time by the program end time. Decide
When the program end time of the program received by the digital broadcast wave cannot be acquired, the intermittent ratio is set to a priority indicating whether the image quality input by the user or the viewing time is given priority and the remaining battery power. A portable viewing device characterized in that it is determined by a table in which amounts are associated with each other. 2. The portable viewing device according to claim 1 , wherein the intermittent ratio is set to increase as the remaining battery level decreases. 3. The portable viewing device according to claim 1 or 2 , wherein the intermittent ratio is reset under a predetermined condition. The portable viewing device according to any one of claims 1 to 3 , wherein the intermittent viewing mode is configured to be able to be set to omit generation of either video or audio. Viewing device. The portable viewing device according to any one of claims 1 to 4, even when the intermittent viewing mode is selected by the user, is configured such that there is a case where the normal viewing mode is executed under a predetermined condition A portable viewing device. In a portable viewing device having a drive battery and configured to reproduce a stream from a recording medium to generate a frame or to reproduce a frame from a recording medium, the independent frame that can be decoded by itself Normal playback viewing mode that decodes all of the accompanying frame groups that can be decoded in consideration of independent frames for playback viewing, and intermittent playback viewing mode that decodes the original frame but does not decode part or all of the accompanying frame groups (The ratio of the accompanying frames that are not decoded to the entire accompanying frames group is referred to as an intermittent ratio).
When the end time of the content being played back by the recording medium can be acquired, and when the viewable time due to the remaining battery level of the driving battery is equal to or longer than the end time, the normal playback viewing mode When viewing processing is performed and the viewable time is less than the end time, the number of frames to be decoded in the intermittent playback viewing mode is determined at an intermittent rate based on a value obtained by dividing the viewable time by the end time. ,
If the end time of the content being played back by the recording medium cannot be acquired, the intermittent ratio is given a priority indicating which priority is given to the image quality input by the user or the viewing time, and the remaining battery level. A portable viewing device characterized in that it is determined by a table in which the items are associated with each other. 7. The portable viewing device according to claim 6 , wherein the intermittent ratio is set so as to increase as the remaining battery level decreases. 8. The portable viewing device according to claim 6 or 7 , wherein the intermittent ratio is reset under a predetermined condition. The portable viewing device according to any one of claims 6 to 8, in the intermittent playback viewing mode, characterized in that it is configured to allow the setting to eliminate the production of one of the video and audio mobile Type viewing device. The portable viewing device according to any one of claims 6 to 9, configured such cases even when the intermittent playback viewing mode is selected by the user, the normal play viewing mode under predetermined conditions is performed A portable viewing device characterized by that.

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