JP2006352783A - Output method and output device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an output method and an output device for immediately starting output and outputting high-quality video and audio when the output is continuously executed, in an output device of a cellular phone etc. for receiving and outputting distribution data in which loss compensation data are added to output data such as video data and audio data. <P>SOLUTION: A generating device 2 generates distribution data in which the loss compensation data for compensating a loss portion per block are added to the output data of the video data and audio data, and distributes the generated distribution data as streaming data. The output device 1 receives the distribution data which are distributed, and performs output based on the output data included in the distribution data as output when output starts. After receiving a predetermined operation, if a predetermined condition such as lapse of a predetermined time from the output start based on the distribution data is satisfied, the output device 1 performs output based on the output data for which loss compensation processing based on the loss compensation data is performed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an output method for receiving distribution data in which loss compensation data for compensating for a missing portion is added to output data, and performing output based on the output data related to the received distribution data, and an output device to which the output method is applied In particular, the present invention relates to an output method and an output device capable of promptly starting output based on output data such as streaming data and compensating for a missing portion.

  Video distribution systems that distribute various types of video data such as movies, television broadcasts, concerts, and the like are widespread (see, for example, Patent Document 1).

  In addition, recent video distribution systems are developing not only for wired networks but also for wireless networks, for example, mobile phones as devices on the receiving side, and more channels for distributed video data are being promoted. Yes.

  In such a video distribution system, part of the video data may be lost due to various noises before the distributed video data reaches the receiving device. In particular, when video data is transmitted wirelessly to a mobile phone, not only the effects of electromagnetic noise but also the effects of obstacles such as buildings are large, so countermeasures against deficiencies are required beyond transmission via wired networks. It becomes.

  Therefore, a systematic code type loss compensation code method is employed as a method for compensating for the loss of video data. In the loss compensation coding method, the original video data (original data) is divided into blocks of a predetermined length, and loss compensation coding is made possible to compensate for the missing portions by adding the loss compensation data to the data divided into blocks. The data subjected to loss compensation coding is divided into packet units and distributed from the transmission side device, and the reception side device generates block unit data from the received data, and based on the block unit data Then, defect compensation decoding is performed to compensate for the defect.

  In the systematic code type loss compensation code method, for example, when original data represented by three data of x, y, and z is distributed from a transmission side device, exclusive OR is performed on the data x, y, and z. The data w (= x XOR y XOR z) in relation is added as missing compensation data and distributed. Thus, for example, even if the data received by the device on the receiving side is only x, y, w, the data w can be received because it is in an exclusive OR relationship with the data x, y, z. Data x can be obtained from data x, y, w, and original data x, y, z can be compensated.

FIG. 6 is an explanatory diagram conceptually showing an example of data subjected to loss compensation coding. Data with numbers such as 1, 2,..., 10,..., 20,... Indicate video data that is original data divided by a predetermined data length, and are denoted by symbols such as R1, R2,. The attached data indicates missing compensation data. Also, the data shown in FIG. 6 is transferred in the order of 1, 2,..., 10, R1, 11,. The example shown in FIG. 6 shows a form in which blocks such as a first block, a second block,... Are formed by adding one missing compensation data to the original 10 pieces of video data. When the receiving side device such as a mobile phone receives the video data subjected to the loss compensation coding shown in FIG. 6, the transmission speed of the video data received by the mobile phone is 128 Kbps, and the block size of one block is 160 Kbytes. If this is the case, the time required for receiving the video data constituting one block is 10 seconds. Since loss compensation is performed in units of blocks, the ability to compensate for packet loss can be enhanced by increasing the block size of one block and increasing the loss compensation data included in the block.
JP 2004-80169 A

  However, the larger the block size that is the unit of loss compensation encoding, the longer the time from the start of receiving the loss compensation encoded video data to the start of video output based on the received video data. There is a problem. When receiving video data encoded with missing compensation, after completing reception of one block, after performing loss compensation processing based on the missing compensation encoded data included in the received block, the video based on the video data is displayed. It is because it will output. For example, as described with reference to FIG. 6, if it takes 10 seconds to receive the data constituting one block, it takes 10 seconds or more from the start of data reception until the video is output. . In particular, when so-called zapping is performed in which the number of channels is increased and the output video is switched one after another, the time from the start of data reception to the output is stressed to the viewer.

  In addition, when transmitting video data to which no missing compensation code is added, the receiving device does not need to wait for the reception of data constituting one block, and therefore promptly after receiving video data. Although an image based on the image data can be output, the missing portion is not compensated, so that the image is likely to be distorted and the image quality is deteriorated.

  The present invention has been made in view of such circumstances, and in an output device that receives and outputs distribution data in which loss compensation data is added to output data such as video data, an output included in the distribution data at the start of output. An output method capable of performing output based on data, and then performing output based on output data obtained by performing defect compensation processing based on defect compensation data, thereby preventing a reduction in output quality such as video quality and enabling prompt output And an output device to which the output method is applied.

  An output method according to a first aspect of the present invention is an output method for receiving distribution data in which loss compensation data for compensating for a missing portion is added to the output data, and performing output based on the output data related to the received distribution data. The output is based on the output data included in the distribution data, and then the output is based on the output data that has been subjected to the loss compensation processing based on the loss compensation data.

  An output device according to a second aspect of the present invention is an output device that receives distribution data in which loss compensation data for compensating for a missing portion is added to the output data, and performs output based on the output data related to the received distribution data. First means for performing output based on the output data included in the distribution data, and second means for performing output based on the output data subjected to the loss compensation processing based on the loss compensation data after the output by the first means. It is characterized by providing.

  The output device according to a third aspect of the invention is the output device according to the second aspect, further comprising operating means for accepting an operation, wherein the second means is configured to start output based on an operation accepted by the operating means. Features.

  The output device according to a fourth aspect of the present invention is the second or third aspect of the present invention, further comprising time-counting means for timing the time after the start of the output by the first means, wherein the second means is time-measured by the time-measurement means. The output is started when the predetermined time reaches a predetermined time.

  An output device according to a fifth invention is configured to receive distribution data of a plurality of channels in any one of the second invention to the fourth invention, further comprising a selection means for selecting the distribution data related to the output, The first means is configured to perform output based on output data included in the distribution data as an output at the time of starting output related to the distribution data selected by the selection means.

  The output device according to a sixth invention is the output device according to any one of the second invention to the fifth invention, wherein the output data is streaming data related to video data and / or audio data, and the output of the first means and the second means. Is an output of video and / or audio.

  In the present invention, the output based on the output data included in the distribution data is performed as the output at the start of output, so that the output is started without waiting for reception of data for one block to which the missing compensation data is added. Therefore, it is possible to shorten the time from the start of receiving the distribution data to the output.

  Also, in the present invention, when a predetermined condition is satisfied after a predetermined operation is received and a predetermined time elapses after the start of output based on distribution data, the output is performed after performing the loss compensation processing, so that the video quality It is possible to prevent the output quality from being degraded.

  The output method and output device according to the present invention generates distribution data in which loss compensation data for compensating for a missing portion in block units is added to output data such as video data and audio data, and distributes the generated distribution data as streaming data The present invention is applied to an output device that receives received distribution data and outputs video and audio based on output data related to the received distribution data. Then, the output device performs output based on the output data included in the distribution data as an output at the start of output, and after receiving a predetermined operation, after a predetermined time has elapsed from the start of the output based on the distribution data When the condition is satisfied, output based on the output data that has been subjected to the loss compensation processing based on the loss compensation data is performed.

  In the present invention configured as described above, at the start of output, the output is performed based on the output data included in the distribution data, so that the output can be performed without waiting for the reception of data for one block to which the loss compensation data is added. Since it is started, it is possible to shorten the time from the start of receiving the distribution data until the output is performed.

  In addition, since the present invention outputs video and audio after performing defect compensation processing after satisfying a predetermined condition, it is difficult for output abnormalities such as video disturbance to occur and prevents deterioration of output quality such as video quality. It has an excellent effect such as being able to do so.

  In the present invention, there is a possibility that the same video is temporarily output again due to a delay associated with the defect compensation process immediately after switching from performing the defect compensation process to performing the defect compensation process. However, when the output is continued, the temporary re-output of the video immediately after the switching does not give a great stress to the viewer and does not become a big problem.

  Further, the present invention receives distribution data of a plurality of channels, selects distribution data to be output from the received distribution data of the plurality of channels, particularly when performing so-called zapping, which switches the channels related to output one after another. Since the time from the selection of data to the output of video and audio is short, there is an excellent effect that the viewer is not stressed. Since defect compensation processing is not performed at the start of output, for example, there is a risk of image disturbance. However, slight image disturbance during zapping does not cause significant stress on the viewer. It will not be a problem.

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof. FIG. 1 is an explanatory diagram conceptually showing an example of a video distribution system to which the output method of the present invention is applied. 1, reference numeral 1 denotes an output device such as a mobile phone that outputs video and audio based on video data and audio data received by wireless communication. Video data and audio data received by the output device 1 are generated as distribution data subjected to loss compensation coding by a generation device 2 such as a server computer, and are streamed via a wireless base station. Note that channels are assigned to distribution data to be distributed by streaming, and the output device 1 outputs video and audio based on video data and audio data related to distribution data of one channel selected from a plurality of channels. . However, the distribution data of each channel may be generated and distributed by one generation device 2, or may be generated and distributed by a plurality of generation devices 2, respectively.

  FIG. 2 is a block diagram showing a configuration example of a video distribution system to which the output method of the present invention is applied. The output device 1 using a mobile phone includes a control means 101 such as a CPU (Central Processing Unit) for controlling various processes such as various communication processes, voice input / output processes, and image display processes, and various information such as computer programs and data. Recording means 102 such as a ROM (Read Only Memory) and a RAM (Random Access Memory).

  Further, the output device 1 outputs the communication means 103 such as an antenna and a communication control circuit for performing communication such as reception of distribution data distributed by telephone and streaming, and the distribution data of the plurality of channels received by the communication means 103. Selecting means 104 for selecting distribution data relating to the channel. In this embodiment, the communication unit 103 is shared by telephone communication and distribution data reception. However, the communication unit 103 may be provided for each communication.

  Further, the output device 1 has a cache memory that temporarily records the received loss compensation encoded delivery data, such as an integrated circuit that performs processing for compensating for the loss of the delivery data recorded in the cache memory. When the loss compensation decoding means 105 and the distribution data are data obtained by compressing and encoding the original data of video data and audio data in an encoding format such as MPEG (Motion Picture Expert Group), the video data is decompressed and decoded. And decompression decoding means 106 such as an integrated circuit for generating the original data of the audio data. Instead of mounting an integrated circuit as the loss compensation decoding means 105 and the decompression decoding means 106, the processing for compensating for the loss may be executed by executing a computer program recorded in the recording means 102.

  Furthermore, the output device 1 includes a voice input unit 107 such as a microphone and a voice processing circuit, a voice output unit 108 such as a speaker and a voice processing circuit, and an operation unit 109 such as a push button that accepts key inputs such as alphanumeric characters and various commands. , A display means 110 such as a liquid crystal display for displaying various information such as key input information and information to be transmitted and received, and a time measuring means 111 such as a clock and a timer circuit. As the operation means 109, push buttons such as a selection button 109a for starting video and audio viewing based on distribution data and selecting a channel, and a loss compensation processing start button 109b for starting loss compensation processing are arranged. .

  The generation device 2 includes a control unit 21 such as a CPU that controls the entire apparatus, a recording unit 22 such as a hard disk that records original data of video data and audio data to be distributed, video data recorded in the recording unit 22, and Compression encoding means 23 that compresses and encodes original data of audio data in an encoding format such as MPEG, and video data and audio data (output data) compressed and encoded by the compression encoding means 23 are divided into blocks. And loss compensation encoding means 24 for generating delivery data to which loss compensation data for compensating for the loss is added, and communication means 25 for delivering the delivery data via the base station. Note that when the output method of the present invention is applied to a video distribution system for capturing an image of an imaging target such as a concert or an urban area and distributing it live, video data and audio data are not recorded in the recording unit 22 in advance, but a camera or the like. Video data and audio data may be generated by imaging using the imaging unit, and the generated video data and audio data may be compression encoded and loss compensation encoded to generate distribution data. In addition, video data and audio data that have been compression-encoded in advance may be recorded in the recording unit 22, and in that case, the compression-encoding unit 23 is unnecessary. Further, when the distribution data is distributed from the generation device 2 to the output device 1 at a sufficiently high speed, the original data of video data and audio data may be distributed without compression encoding.

  Next, distribution data distributed from the generation device 2 will be described. FIG. 3 is an explanatory diagram conceptually showing an example of distribution data distributed from the generation device 2 used in the video distribution system to which the output method of the present invention is applied. In FIG. 3, data with numbers such as 1, 2,..., 10,..., 20, etc. indicate video data and audio data which are output data divided into predetermined data lengths. Data with symbols such as R 2,... Indicate missing compensation data added by the missing compensation encoding means 24. The data shown in FIG. 3 is distributed in the order of 1, 2,..., 10, R1, 11,. The missing compensation data is data that is in an exclusive OR relationship with a predetermined number of data divided by a predetermined data length. By adding missing compensation data to the predetermined number of data, the first block, A block serving as a unit of defect compensation processing shown as a second block,. In the example shown in FIG. 3, one block is configured by adding one deficiency compensation data to 10 video data and audio data divided into predetermined data lengths.

  Also, the distribution data generated by the loss compensation encoding to which the loss compensation data is added is distributed from the generation device 2 in packet units, which are transmission units having a data length smaller than that of the block. In each packet, a code indicating a channel of distribution data is shown as header information.

  Next, processing of various devices used in a video distribution system to which the output method of the present invention is applied will be described. FIG. 4 is a flowchart showing the output process of the output device 1 of the present invention. A viewer who views video and audio output from the output device 1 operates the output device 1 to receive distribution data, output video and audio, and select a channel to be viewed. The output device 1 receives an operation for starting viewing and selecting a channel from the selection button 109a under the control of the control unit 101 (step S1), receives the distribution data at the communication unit 103 (step S2), and receives it. The distribution data of the channel selected from the distribution data is selected by the selection means 104 (step S3), and the selected distribution data is recorded in the cache memory of the loss compensation decoding means 105 (step S4). The channel selection in step S3 is performed at the start of receiving distribution data or when switching channels.

  Then, the output device 1 extracts video data and audio data, which are output data included in the recorded distribution data, under the control of the control unit 101 (step S5), and based on the extracted video data and audio data, the display unit 110 and the audio output means 108 start outputting video and audio (step S6). When the video data and audio data that are the extracted output data are compression-encoded data, the video and audio are output after being decompressed and decoded by the decompression decoding means 106. As shown in steps S5 to S6, the output device 1 of the present invention performs output based on the output data included in the distribution data as a process at the time of starting the output of the selected distribution data.

  The output device 1 that has started outputting video and audio by the processing shown in steps S5 to S6 uses the time measuring means 111 to measure the time since the start of the output, and the time measuring means 111 measures the time. When the time after the start of output reaches a predetermined time, the time measuring means 111 generates an interrupt command for starting the loss compensation processing. Further, when the operation for starting the defect compensation process is received from the defect compensation process start button 109b even when the time after the start of output timed by the time measuring means 111 has not reached the predetermined time, the defect compensation process start button is received. 109b generates an interrupt instruction for starting the loss compensation process.

  The output device 1 continues to detect whether or not the interrupt instruction for starting the loss compensation processing is generated in the control unit 101 (step S7), and when the generation of the interrupt instruction is detected (step S7: YES). Then, the loss compensation decoding means 105 performs loss compensation processing of video data and audio data as output data based on the loss compensation data included in the distribution data recorded in the cache memory (step S8), and performs the loss compensation processing. Based on the recorded video data and audio data, output of video and audio is started from the display means 110 and the audio output means 108 (step S9). When the output of video and audio based on the video data and audio data that have been subjected to the loss compensation processing in steps S8 to S9 is started, the output of video and audio that is not subjected to the loss compensation processing in steps S5 to S6 is stopped. When the video data and audio data that are output data subjected to the loss compensation process are compression-encoded data, the video data and audio are output after being decompressed by the decompression decoding means 106. As shown in steps S7 to S9, the output device 1 according to the present invention detects the occurrence of an interrupt instruction for starting a loss compensation process after starting output based on the output data included in the distribution data. Perform output based on the output data.

  Note that, when an operation for a channel is received again during the output process described with reference to FIG. 4, an interrupt instruction for restarting the output process is generated based on the received operation, and the process returns to step S <b> 1 to perform the subsequent processes. repeat. That is, when an operation called so-called zapping, in which channels for output are switched one after another, is accepted, the processing from step S1 is repeated every time the channel is switched.

  FIG. 5 is an explanatory diagram conceptually showing an example of distribution data received by the output device 1 of the present invention. In FIG. 5, data with numbers such as 1, 2,..., 10,..., 20, etc. indicate video data and audio data that are output data divided into predetermined data lengths. Data with symbols such as R2,... Indicate missing compensation data. Then, the output device 1 receives the data shown in FIG. 5 in the order of 1, 2,..., 10, R1, 11, ..., 20, R2, 21,. The missing compensation data is data that is in an exclusive OR relationship with a predetermined number of data divided by a predetermined data length. By adding missing compensation data to the predetermined number of data, the first block, A block serving as a unit of defect compensation processing shown as a second block,. When the output device 1 receives and records the distribution data composed of the output data and the loss compensation data, the processing of steps S5 to S6 does not require receiving all the data forming the first block. , 1,... Are extracted, and output based on the extracted output data is started. Even when the loss compensation data indicated as R1 has not been received and all the data forming the first block has not been received at the time when output by the processing of steps S5 to S6 is started, If the output data indicated as... Is received, the output device 1 cannot perform the loss compensation process, but can start output based on the output data.

  When the output device 1 has received and recorded the distribution data up to the output data indicated as 22 belonging to the third block at the time of starting the loss compensation processing, first, the second block is processed by the processing of steps S8 to S9. The output based on the output data to which the loss compensation processing based on the output data having the numbers 11 to 20 and the missing compensation data having the symbol R2 is applied is started. Therefore, at this time, if the output process based on the output data with the numbers 11 to 20 belonging to the second block is started, the same video and audio will be output, but this is temporary. Therefore, it is considered that viewers do not feel great stress. When the output device 1 has received and recorded the distribution data up to the output data indicated as 2 belonging to the first block at the time of starting the loss compensation processing, it receives the loss compensation data labeled with R1. Until this time, output is started by the processing of steps S5 to S6.

  In the above-described embodiment, the form applied to the system that distributes video data and audio data by streaming is shown. However, the present invention is not limited to this, and various forms such as application to a system that distributes video data or audio data. It is possible to expand to.

  In the above embodiment, a mobile phone is used as an output device. However, the present invention is not limited to this, and a communication device other than a mobile phone may be used. It is possible to develop various forms such as distributing audio data.

It is explanatory drawing which shows notionally an example of the video delivery system to which the output method of this invention is applied. It is a block diagram which shows the structural example of the video delivery system to which the output method of this invention is applied. It is explanatory drawing which shows notionally an example of the delivery data delivered from the production | generation apparatus used with the video delivery system to which the output method of this invention is applied. It is a flowchart which shows the output process of the output device of this invention. It is explanatory drawing which shows notionally an example of the delivery data which the output device of this invention received. It is explanatory drawing which shows notionally an example of the data which performed loss compensation encoding.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Output device 104 Selection means 105 Missing compensation decoding means 108 Audio | voice output means 109 Operation means 109a Selection button 109b Missing compensation process start button 110 Display means 111 Time measuring means 2 Generation apparatus 24 Missing compensation encoding means

Claims (6)

In the output method of receiving the distribution data in which the defect compensation data for compensating for the missing portion is added to the output data, and performing the output based on the output data related to the received distribution data,
As output at the start of output, output based on the output data included in the distribution data,
Next, an output method comprising: performing output based on output data obtained by performing defect compensation processing based on defect compensation data. In an output device that receives distribution data in which defect compensation data that compensates for a missing portion is added to output data and performs output based on output data related to the received distribution data,
A first means for performing output based on output data included in the distribution data as an output at the start of output;
An output device comprising: second means for performing output based on output data obtained by performing defect compensation processing based on defect compensation data after output by the first means. An operation means for receiving an operation;
The output device according to claim 2, wherein the second means is configured to start output based on an operation received by the operation means. Further comprising time measuring means for measuring the time after starting the output by the first means,
4. The output device according to claim 2, wherein the second means is configured to start output when the time measured by the time measuring means reaches a predetermined time. 5. It is configured to receive multi-channel distribution data,
Further comprising a selection means for selecting distribution data relating to the output;
The first means is configured to perform output based on output data included in the distribution data as an output at the start of output related to the distribution data selected by the selection means. 5. The output device according to any one of 4. The output data is streaming data related to video data and / or audio data,
The output device according to any one of claims 2 to 5, wherein the outputs of the first means and the second means are video and / or audio outputs.

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