JP2005244473A - Digital broadcast receiving terminal, data reproduction method thereof, and analog broadcast receiving terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a digital broadcast receiving terminal technology with good user-friendliness nature. <P>SOLUTION: When a reproducing operation of received digital data is temporarily stopped, the digital data are continuously received during the temporary stop. The continuously received digital data are stored in a storage means in the state that the amount of the data is reduced. When the temporary stop is released and the reproducing is re-started, the stored digital data are reproduced in a time sharing state, and thereafter shifted to the reproduction automatically in real time. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a data reproduction technique in a broadcast receiving terminal, and more particularly to a technique in a case where a reproduction operation is paused and then resumed.

  The digital broadcasting system is a broadcasting system that transmits compressed audio / video digital data from a broadcasting station and decodes and reproduces the received compressed audio / video digital data on the receiving side. For example, in Japanese Patent Laid-Open No. 2003-244951 (Patent Document 1), Japanese Patent Laid-Open No. 2001-320657 (Patent Document 2), and Japanese Patent Laid-Open No. 2000-350130 (Patent Document 3) As a technique for time-shifting and reproducing the digital broadcast data, a time-short time-shift reproduction technique is described in which the reproduction time is shortened by reproducing at a speed faster than the actual broadcast time. The received broadcast data is stored as data with no excess or deficiency.

Japanese Patent Laid-Open No. 2003-244591

JP 2001-320657 A JP 2000-350130 A

In the above conventional digital broadcast receiving terminal, consideration is not given to the storage of received data and the limitation of the storage capacity therefor, which is important for portable use, for example. For this reason, when playback is paused, reception data may not be stored within a predetermined storage capacity for all periods during the pause.
In view of the above-described prior art, the problem of the present invention is that in the digital broadcast receiving terminal, it is possible to save received data in a predetermined storage capacity in a predetermined storage capacity, and to solve the suspension. When the reproduction is resumed, the stored digital data can be reproduced in a time-shifted state.
An object of the present invention is to solve such problems and to provide a digital broadcast receiving terminal technology with good usability.

  In order to solve the above problems, in the present invention, when the reproduction operation of the received broadcast data is paused, the broadcast data is continuously received during the pause, and the continuously received broadcast data is converted into digital data. When the data amount is reduced and saved in the storage means, and the reproduction is resumed after releasing the pause, the saved digital data is reproduced in a time-shifted state, and then automatically transferred to real-time reproduction.

  According to the present invention, in the broadcast receiving terminal, the received data in the entire paused period can be reproduced in a time-shifted state after the suspension is canceled, and the usability of the terminal can be improved.

The best mode for carrying out the present invention will be described below with reference to the drawings.
1-3 is explanatory drawing of the 1st Embodiment of this invention. FIG. 1 is a structural example diagram of a broadcast receiving terminal as a first embodiment of the present invention, FIG. 2 is an explanatory diagram of an operation procedure of the broadcast receiving terminal of FIG. 1, and FIG. 3 is an explanatory diagram of storing digital data It is. The case of a portable terminal is assumed as the broadcast receiving terminal.

  In FIG. 1, 101 is a control means such as a microcomputer for controlling the entire broadcast receiving terminal, 102 is an operating means for receiving an instruction from a user, and 103 is a first for receiving digital broadcast data (digital data). , 104 is a channel selection unit that selects received digital data, 105 is a storage unit that stores an operation program of the control unit 101, received digital data, and the like, and 106 is a wireless signal such as a telephone signal or a mail signal. A second antenna for transmitting / receiving a communication signal, 107 is a communication means for performing processing for communication such as a telephone signal and a mail signal, 108 is a video decoding means for decoding compressed video data, 109 is A display unit that displays the video decoded by the video decoding unit 108, 110 an audio decoding unit that decodes the compressed audio data, and 111 a sound An audio output unit that outputs audio decoded by the decoding means 110, 112 is a power supply unit for supplying power to each block.

  When digital data is received by the first antenna 103, it is taken into the control means 101 via the channel selection means 104 and temporarily stored in the storage means 105. The temporarily stored digital data is separated into compressed video data and compressed audio data under the control of the control means 101. The separated compressed video data is decoded by the video decoding unit 108 and displayed on the display unit 109. The separated compressed audio data is decoded by the audio decoding unit 110 and output as audio from the audio output unit 111.

  On the other hand, when a wireless communication signal such as a telephone signal or a mail signal is received by the second antenna 106, it is taken into the control unit 101 as digital data via the communication unit 107 and temporarily stored in the storage unit 105. The control means 101 separates the temporarily stored digital data of the wireless communication signal into character data such as mail and voice data such as a call, the character data is displayed on the display unit 109, and the voice data is a voice output unit. 111 is output as audio.

FIG. 2 is an explanatory diagram of an operation procedure of the broadcast receiving terminal of FIG.
In FIG.
(1) Reception of digital broadcast data (digital data) is started in accordance with a user instruction from the operation unit 102 (step S201).
(2) The control unit 101 temporarily stores the received digital broadcast data (compressed digital data) in the storage unit 105 (step S202).
(3) The control unit 101 separates the compressed digital data (received digital broadcast) temporarily stored in the storage unit 105 into video data and audio data, and the video data after separation is the video decoding unit 108. (Step S203).
(4) The decoded video data is displayed on the display unit 109 (step S204).
The separated audio data is decoded by the audio decoding unit 110 and output as audio from the audio output unit 111.
(5) The control means 101 determines whether or not there is a user instruction regarding a pause (pause of the reproduction operation) (step S205). At this time, the control unit 101 receives a user instruction from the operation unit 102 and makes a determination. For example, when the second antenna 106 receives a wireless communication signal such as a telephone signal or a mail signal, the pause instruction is given by the user to perform a telephone call or a mail communication. The pause instruction may be performed in accordance with a user instruction. However, when a wireless communication signal such as a telephone signal or a mail signal is received, the pause operation may be performed without the user instruction. In addition to receiving a wireless communication signal such as a telephone signal or e-mail signal, the transition to the pause operation can be performed by a timer operation or control when the battery level is low, etc. It is possible without depending on. Furthermore, the transition to the pause operation can be performed by a user instruction based on, for example, a physiological factor of the user.

(6) If the result of determination in step S205 is that there is no pause instruction from the user, the operations in steps S202 to S204 are repeated. This is the state when the user is viewing a digital broadcast.
(7) If the result of determination in step S205 is that there is a pause instruction from the user, the control means 101 reduces the amount of received digital broadcast data (compressed digital data) to the storage means 105. Save (step S206). The control means 101 is means for reducing the frame rate of video data of digital data continuously received during the pause (pause), means for selecting a part of the video data and cutting out a part of the image, or monaural audio data. The data amount is reduced by reducing the frame rate of the video data, cutting out an image by selecting a part of the video data, or monauralizing the audio data.
(8) The control means 101 determines whether or not there is a user instruction regarding pause release (resumption of reproduction of digital data) (step S207). The control unit 101 receives a user instruction via the operation unit 102.
(9) If the result of determination in step S207 is that there is no pause release instruction from the user, the control means 101 determines that the pause state is continued and continues to receive the received digital broadcast data (compressed digital data). Data) is stored in the storage means 105 with the data amount reduced (step S206).
(10) If the result of determination in step S207 is that the user has issued a pause release instruction, the control means 101 determines that the pause state has been released, and receives the received digital broadcast data (compressed digital data). The reduced digital data already stored in the storage unit 105 is reproduced while being stored in the storage unit 105 with the data amount reduced (step S208). Even when the reduced digital data is reproduced in step S208, the same processing operation as in steps S202 to S205 is performed. That is, digital data with a reduced amount of data is temporarily stored in the storage unit 105 and separated into video data and audio data by the control unit 101. The separated video data is decoded by the video decoding means 108 (step S203) and displayed on the display unit 109 (step S204). On the other hand, the separated audio data is decoded by the audio decoding unit 110 and output as audio from the audio output unit 111. If there is no pause instruction from the user, the operation in step S208 is continued. If there is a pause instruction from the user, the process proceeds to step S206 and subsequent steps.

(11) The control unit 101 detects the reduced digital data storage status stored in the storage unit 105, and determines whether or not the reproduction of the reduced digital data stored in the storage unit 105 has ended. It discriminate | determines (step S209).
(12) As a result of the determination in step S209, if the reproduction of the reduced digital data stored in the storage unit 105 is not completed, the control unit 101 continues to receive the received digital broadcast (compressed digital data). Data) is stored in the storage unit 105 with the data amount reduced, and the reduced digital data already stored in the storage unit 105 is reproduced (step S208).
(13) As a result of the determination in step S209, when the reproduction of the reduced digital data stored in the storage unit 105 is completed, the control unit 101 performs normal time when the user is viewing the digital broadcast. The operations in step S202 to step S204 in the state are repeated.
Of the operations in steps S201 to S209, the operation by the control unit 101 is performed by causing the computer in the control unit 101 to execute a procedure corresponding to the operation by an operation program stored in the storage unit 105. Done.

  FIG. 3 is an explanatory diagram of digital data storage in the storage unit 105. FIG. 3 shows the storage status of the reduced data in the storage unit 105 in the above steps S206 and S208, and shows the storage status of a storage FIFO (First In First Out) area for storing the reduced data. Yes.

  FIG. 3A shows the storage state of the storage FIFO area 301 for storing the reduced data until the pause instruction in step S205 is given. In the figure, since there is no pause instruction, the reduced data is not stored.

  FIG. 3B shows the storage state of the storage FIFO area 301 that stores the reduced data until the pause instruction in step S205 is given and the restart instruction in step S207 is given. In the figure, since there is a pause instruction, the reduced data is sequentially stored, and the saved area 302 for storing the reduced data is sequentially increasing.

  FIG. 3C shows the storage state of the storage FIFO area 301 that stores the reduced data until the reproduction of the reduced data stored in step S209 ends when the restart instruction in step S207 is given. It is. In the figure, since the reproduction of the saved reduced data is not finished, the reduced data is sequentially saved, and the reduced data is saved from the saved area 302 for saving the reduced data for reproduction. Are sequentially read, and the saved area 302 for storing the reduced data is sequentially reduced.

  FIG. 3D shows the storage state of the storage FIFO area 301 for storing the reduced data when the playback of the reduced data stored in step S209 is completed, and is reduced for playback. All the reduced data is read from the saved area 302 for saving the data, and the reduced data is not saved.

  Table 1 shows an example of parameters of compressed digital data in digital broadcasting. Examples of the parameters include parameters of compressed video data and compressed audio data according to the MPEG (Moving Picture Experts Group) standard.

  The compressed video data has a frame rate of 15 fps for displaying 15 frames per second, a displayed image size of CIF (Common Intermediate Format) of 352 dots × 288 dots, and an average bit rate for reception of 384 kbps (per second) 384 kbit data is received). The compressed audio data is stereo audio data, and the average bit rate at the time of reception is 96 kbps (data of 96 kbit is received per second). Accordingly, the average bit rate of the sum of the compressed video data and the compressed audio data is 480 kbps (receives 480 kbit data per second). In this case, the data amount for 5 minutes is converted into bytes, 14.4 Mbytes (384,000 × 60 × 5/8) for compressed video data, and 3.6 Mbytes (96,000 × 60 ×) for compressed audio data. 5/8), and the total of the compressed video data and the compressed audio data is 18 Mbytes in 5 minutes. Generally, in a portable terminal, the storage capacity of the storage means built in the housing is at most about 20 Mbytes (some models are 4 Mbytes or less), and the storage capacity of the storage means is all 20 Mbytes. Even if it is used for storing digital broadcasts, it can be stored only for about five and a half minutes, which is a practical limitation.

  Table 2 shows a parameter example (first parameter example) of reduced digital data stored in the storage means in the present invention.

  In the parameter example of Table 2, the compressed video data to be stored is stored by thinning the frame rate to 1 fps (one image is displayed per second). Compressed video data according to the MPEG standard is an I picture (Intra frame) that is an intra-frame coding screen that does not require previous and subsequent predictions, and P that is an inter-frame prediction coding screen that predicts (forward prediction) from a past reproduced image. It consists of a picture (Predictive) and the like. Since the amount of data for an I picture is approximately three times that of a P picture, if the I picture screen is one in 15 (one per second) and the rest is a P picture, the amount of data for the P picture Is 2.82 kbytes ((384/8) / 17) / sheet, and the data amount of the I picture is 8.47 kbytes (2.8 k × 3) / sheet. If only I pictures are stored (reduced storage), the amount of video data to be stored is 8.4 kbytes / second (8.4 k × 8 = 67.8 kbps), and the data amount for 5 minutes is 2.5 M. This is a byte (8.47 k × 60 × 5). Since the compressed audio data is the same as in Table 1, the total of the compressed video data and the compressed audio data is 6.14 Mbytes in 5 minutes. If the entire storage capacity of 20 Mbytes of the storage means is used for storing digital broadcasts, it becomes about 16.3 minutes, and practical restrictions are reduced.

  Table 3 shows a parameter example (second parameter example) of the reduced digital data to be stored in the present invention.

  In the parameter example in Table 3, in addition to the parameters obtained by thinning out the compressed video data in Table 2, the compressed audio data is reduced by half from 96 kbps stereo (2 channels) to 48 kbps monaural (1 channel). Yes. As a result, the data amount of the compressed audio data for 5 minutes is 1.8 Mbytes (3.6 MB / 2), and the total of the compressed video data and the compressed audio data is 4.3 Mbytes for 5 minutes. If the entire storage capacity of 20 Mbytes of storage means is used for storing digital broadcasts, it takes about 23 minutes, and practical restrictions are almost eliminated.

  Table 4 shows a parameter example (third parameter example) of the reduced digital data to be stored in the present invention.

  In the parameter example in Table 4, in addition to thinning out the compressed video data in Table 3 and monauralizing the compressed audio data, the image size to be displayed is 320 dots × 240 which is a QVGA (Quarter Video Graphics Array) size. Dots. The display screen size is almost 3/4, and the compressed video data is reduced by about 25%. As a result, the data amount of the compressed video data for 5 minutes is 1.9 Mbytes (2.5 MB × (352 × 288) / (320 × 240)), and the total of the compressed video data and the compressed audio data is 5 minutes. Thus, it becomes 3.7 Mbytes. If the entire storage capacity of 20 Mbytes of storage means is used for storing digital broadcasts, it takes about 27 minutes, and practical restrictions are almost eliminated. As a means for reducing the display image (video) size, in addition to partial segmentation of video data as described above (= image segmentation by selecting a part of video data), averaging by pixel aggregation, video data Re-compression and pixel data decimation.

At the time of playback, the video data is only an I picture, so the displayed video is not a moving picture but a picture-like screen, and the playback time is shorter and shorter than the actually received broadcast time. The As a user, it is not actually broadcast video, but as a story, it can be understood. Also, the audio data to be reproduced is reproduced in a short time in order to match the reproduction speed of the video data.
By performing such a short-time playback, the reduced stored digital data is played back shorter than the actual broadcast time for the short-time playback, and the short-time playback catches up with the actual digital broadcast playback time. Transition to reception playback.

  Methods for reducing the amount of data include the frame rate reduction, monaural audio data, and image size reduction described in Tables 2 to 4, but there are various other methods, for example, There are techniques such as lowering the bit rate of video data and recompressing and saving, or saving only audio.

  In the first embodiment, the storage means 105 that is a semiconductor memory (storage capacity of about 20 Mbytes) in the portable terminal is assumed in the storage FIFO (First In First Out) area for storing the reduced data. However, for example, a portable miniSD card (mini Secure Digital memory card) of about 128 Mbytes that can be mounted can also be used. In this case, since the storage capacity of the storage FIFO (First In First Out) area that can be stored is expanded to about 6.4 times, the length of the broadcast time of the digital broadcast storing the reduced digital data can be increased, It is possible to reduce the amount of reduction of the bit rate of the digital data to be reduced and improve the image quality (adding not only an I picture but also a P picture) and sound quality.

  According to the first embodiment of the present invention, even when the playback operation is paused in the digital broadcast receiving terminal, the received data in all the paused periods is time-shifted after the pause is released. It is possible to reproduce in a state, and the usability of the receiving terminal can be improved.

FIG. 4 is a configuration example diagram of a broadcast receiving terminal as the second embodiment of the present invention. This broadcast receiving terminal is an analog broadcast receiving terminal that receives analog broadcast data and reproduces it as digital data. 4, the same components as those in FIG. 1 are denoted by the same reference numerals as those in FIG.
In FIG. 4, 401 is an antenna (first antenna) for receiving analog broadcast data, 402 is a channel selection means for selecting the received analog broadcast data and converting it into digital data, and 403 is the selected digital data. Among these, video compression means 404 as a compression means for compressing video data, and 404 is an audio compression means as a compression means for compressing audio data among the selected digital data. The channel selection means 402 separates into video information and audio information and incorporates an AD converter, and converts the separated analog signal into a digital signal (digital data).

When the analog broadcast data is received by the antenna 401, the analog broadcast data is separated into video information and audio information in the channel selection means 402 under the control of the control means 101, and converted into respective digital data by the AD converter. The Video digital data and audio digital data are taken into the control means 101 and further temporarily stored in the storage means 105.
The temporarily stored video digital data and audio digital data are read out and compressed under the control of the control means 101. That is, the video digital data is compressed by the video compression unit 403, and the compression result is taken into the control unit 101 and temporarily stored in the storage unit 105. Similarly, the audio digital data is compressed by the audio compression unit 404, and the compression result is taken into the control unit 101 and temporarily stored in the storage unit 105.
The compressed digital data temporarily stored in the storage unit 105 is processed in the same manner as in the first embodiment when the reproduction operation is paused and then resumed.

  According to the second embodiment of the present invention, the analog broadcast receiving terminal can reproduce the received data in the entire period in which the reproduction operation is paused in a time-shifted state after releasing the pause. For this reason, the usability of the receiving terminal can be improved.

1 is a configuration example diagram of a broadcast receiving terminal as a first embodiment of the present invention. It is explanatory drawing of the operation | movement procedure of the terminal of FIG. It is explanatory drawing of preservation | save of digital data. It is a structural example figure of the broadcast receiving terminal as the 2nd Embodiment of this invention.

Explanation of symbols

101 ... control means,
102 ... operation means,
103, 106, 401 ... antenna,
104, 402 ... channel selection means,
105. Storage means,
107: Communication means,
108: Video decoding means,
109 ... display section,
110 ... voice decoding means,
111 ... Audio output unit,
112 ... power supply,
403 ... video compression means,
404: Audio compression means.

Claims (6)

A digital broadcast receiving terminal capable of receiving a digital broadcast,
An antenna for receiving digital data of the digital broadcast;
A channel selection means for selecting the received digital data;
Storage means for storing the selected digital data;
Reproducing means for reproducing the selected digital data;
Control means for controlling the channel selection means, the storage means, and the reproduction means;
And when the playback operation of the received digital data is paused, the control means continuously receives the digital data during the pause and stores the received digital data by reducing the data amount. The digital data is stored in a means, and when the reproduction is resumed after releasing the pause, the stored digital data is read out and controlled to be reproduced in a time-shifted state by the reproduction means. Broadcast receiving terminal. A digital broadcast receiving terminal capable of receiving a digital broadcast,
A first antenna for receiving the digital broadcast;
Channel selection means for selecting the received digital broadcast signal;
Storage means for storing the selected digital data;
A second antenna for transmitting and receiving telephone or email signals;
Communication means for performing processing for communication of the telephone signal or mail signal;
Reproducing means for decoding the selected digital data, performing display or output based on the decoding result, and performing display or output for communication of the telephone signal or mail signal;
Control means for controlling the channel selection means, the storage means, the communication means and the reproduction means;
And the control means continuously receives the digital data during the pause when the digital broadcast reproduction operation is paused for the communication of the telephone signal or the mail signal, and the digital data received continuously. Is stored in the storage means by reducing the data amount, and when the reproduction is resumed after releasing the pause, the stored digital data is read and the digital data is reproduced in a time-shifted state by the reproduction means. A digital broadcast receiving terminal characterized in that it is configured to control as described above.   The control means includes means for reducing the frame rate of video data of digital data continuously received during the pause, means for reducing the video size, or means for monaural audio data. The digital broadcast receiving terminal according to claim 1 or 2, wherein the digital broadcast receiving terminal is configured to reduce the amount of data to be saved by reducing, reducing the video size, or monaural audio data. A data reproduction method for a digital broadcast receiving terminal capable of receiving a digital broadcast,
A first step of receiving the digital broadcast;
A second step of selecting the received digital broadcast signal;
A third step of storing the selected digital data and decoding and reproducing the selected digital data;
A fourth step of performing a process of continuously receiving digital data during the pause and reducing the data amount of the continuously received digital data when the playback is paused;
A fifth step of storing digital data with a reduced amount of data;
A sixth step of reading the stored digital data and replaying the read digital data in a time-shifted state when the pause is released and playback is resumed;
A method for reproducing data of a digital broadcast receiving terminal, wherein digital data is reproduced through   5. In the fourth step, the data amount is reduced by reducing a frame rate of video data of digital data continuously received during the pause, reducing a video size, or monaural audio data. The data reproduction method of the digital broadcast receiving terminal as described. An analog broadcast receiving terminal that receives analog broadcast data and reproduces it as digital data,
A first antenna for receiving the analog broadcast data;
Channel selection means for selecting the received analog broadcast data and converting it into digital data;
Compression means for compressing the selected digital data;
Storage means for storing the compressed digital data;
A second antenna for transmitting and receiving telephone or email signals;
Communication means for performing processing for communication of the telephone signal or mail signal;
Reproducing means for decoding the compressed digital data, performing display or output based on the decoding result, and performing display or output for communication of the telephone signal or mail signal;
Control means for controlling the channel selection means, the storage means, the communication means and the reproduction means;
When the analog broadcast data playback operation is temporarily stopped for the communication of the telephone signal or the mail signal, the control means continuously receives the analog broadcast data during the temporary stop, and receives the continuous reception. A part of digital data formed by conversion and compression from analog data is stored in the storage means, and when the reproduction is resumed after releasing the pause, the stored digital data is read, and the digital data is read An analog broadcast receiving terminal characterized in that the reproduction means controls the reproduction in a time-shifted state.

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