JP2010041183A - Information processor, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reproduce a large unspecified number of contents distributed by MPEG2 through broadcast or a network without taking plenty of time. <P>SOLUTION: When reproducing a content by receiving encoded stream data, this information processor relates and holds reproduction reference information consulted in reproducing the content by information obtained by analyzing the stream data by using a part of the received stream data, executes comparison using a part of stream data when newly receiving the stream data, and reproduces the content by using the held reproduction reference information in accordance with the comparison result. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an information processing apparatus and a program, and more particularly to a technique preferably applied to reproducing an unspecified number of MPEG2s without taking time when receiving content distributed via a network, for example. is there.

  In digital broadcasting, images, sounds, and other necessary data as broadcast programs are transmitted as MPEG (Moving Picture Experts Group) 2-TS (Transport Stream) (hereinafter referred to as transport stream). This transport stream is composed of 188-byte TS packets having a fixed data length. The TS packet includes a header and a payload. The header includes a 13-bit PID (Packet Identifier) for identifying data included in the payload. Further, when data stored in the MPEG2-TS format is distributed, each packet is distributed in a 192-byte format with a 4-byte arrival time at the head of each TS packet. This is called MPEG2-TTS (Timestamped TS) format.

  The data transmitted by the transport stream includes a program association table (PAT) and a program map table (PMT) in addition to programs and content images and sounds. PAT and PMT are a kind of program specification information PSI (Program Specific Information), and are TS packets having a PID different from that of images and sounds. That is, the PID describes the PID of the TS packet storing the PMT, and the PMT describes the PID of the TS packet storing the image and audio of each content transmitted in the transport stream. Therefore, by referring to the PAT and PMT as follows, it is possible to extract only TS packets that constitute the desired content from the transport stream.

  For example, an information processing apparatus that reproduces content distributed via a network first extracts a TS packet in which a PAT is stored from a transport stream, and recognizes the PID of the PMT by referring to the PAT. Furthermore, the information processing apparatus extracts a TS packet in which the PMT of the transport stream is stored based on the PID of the PMT, and recognizes the PID of the TS packet in which, for example, the content image and audio requested by the user are stored. . Based on the PID of the TS packet in which the image (Video) or audio (Audio) of the desired content is stored, the information processing apparatus receives the TS packet in which the Video or Audio of the desired content is stored from the transport stream. Extract.

  As described above, in order to play back the content by interpreting the transport stream, the PID of the PMT is obtained after finding the PAT inserted in the stream at regular intervals, and the PDI of Video and the PID of Audio are obtained from the PMT. Need to get. In practice, it is necessary to find a sequence header position from Video and obtain information necessary for output such as a frame rate and a frame size.

By the way, in Patent Document 1, for example, in a relatively low bit rate broadcasting system in which program specific information (NIT or PMT) cannot be sent frequently, the program specific information acquisition time after channel switching is shortened, and video and audio are presented. A mobile digital broadcast receiver for speeding up is disclosed. In the apparatus, setting is made so that all the first information (PMT) that can be included in the transport stream can be extracted, and the PID of the program configuration data (ES) is obtained from the first information extracted first after switching the channel. get. Then, the program configuration data is extracted from the transport stream and decoded to present video and audio.
JP 2006-173760 A

  In the conventional content reproduction method as described above, information necessary for reproducing the content (eventually, PID of Video or Audio, information necessary for output (sequence header information, etc.)) is acquired. Takes some time. Since it takes time to acquire these pieces of information, as shown in FIG. 6, a lot of Video and Audio TS packets are discarded from when the transport stream is received until the content can be reproduced. Will end up.

  The technique of Patent Document 1 is configured to perform extraction in advance so that all PMTs can be extracted by omitting the procedure of extracting the NIT from the transport stream, analyzing the NIT, specifying the PMT, and extracting the PMT. Yes (it is possible to replace NIT with PAT). That is, it is possible to extract a PMT and extract a Video or Audio TS packet without extracting a PAT. However, the technique of Patent Document 1 is premised on video / audio display in one-segment broadcasting in mobile communication, and PMT extraction conditions are set using a reference table including eight types of PMTs and corresponding PIDs. Yes. For this reason, for example, it cannot be applied to a case where a large number of unspecified contents distributed from a home server via a network are reproduced, and it is also based on the conventional contents reproduction method.

  In view of the above, an object of the present invention is to enable reproduction of an unspecified number of contents distributed by MPEG2 via broadcast or a network without taking time.

  In order to achieve this object, the first information processing apparatus of the present invention analyzes the stream data using a part of the received stream data when receiving the encoded stream data and reproducing the content. Is stored in association with the playback reference information that is referred to during content playback. When new stream data is received, a comparison is made using a part of the stream data, and the stored playback reference is determined according to the comparison result. Play back content using information.

  A second information processing apparatus of the present invention is an information processing apparatus that receives an encoded transport stream and reproduces content, and identifies the received transport stream using a TS packet including a PAT. Identification information generating means for generating information, stream analysis means for analyzing the received transport stream to obtain reproduction reference information to be referred to during content reproduction, and reproduction reference information obtained by the stream analysis means Reproduction reference information holding means held in association with the identification information generated by the information generation means, and each time the transport stream is received, the identification information generated by the identification information generation means and the reproduction reference information holding means are held in association with each other. Content using the playback reference information according to the comparison result Having a content reproducing means for reproducing.

  The third information processing apparatus according to the present invention is the second information processing apparatus according to the second information processing apparatus, wherein when the identification information is the same in the comparison, the content reproduction means When the content is reproduced using the reproduction reference information held by the reproduction reference holding unit, and the identification information of both is different in the comparison, the transport stream is newly analyzed by the stream analysis unit The content is reproduced using the reproduction reference information.

  Further, in the fourth information processing apparatus of the present invention, in the second or third information processing apparatus, when the content reproduction unit compares both pieces of identification information with each other, the received information is transmitted to the transport stream. On the other hand, the content is played back using the playback reference information held by the playback reference holding means, and the stream analysis means analyzes the received transport stream and acquires the playback reference information at the same time as the playback of the content. When the reproduction reference information associated with the identification information already held by the information holding unit is different from the reproduction reference information acquired by the stream analysis unit, the information holding unit updates using the acquired reproduction reference information.

  The fifth information processing apparatus of the present invention is the information processing apparatus according to any one of the second to fourth aspects, wherein the identification information generating unit obtains the identification information by excluding the packet time information from the TS packet including the PAT. Generate.

  A first program of the present invention is a program used in an information processing apparatus that receives an encoded transport stream and reproduces content, and the computer includes a TS including a PAT in the received transport stream. An identification information generation step for generating identification information using a packet, a stream analysis step for analyzing the received transport stream to obtain reproduction reference information to be referred to during content reproduction, and a reproduction obtained in the stream analysis step A reproduction reference information holding step for holding the reference information in association with the identification information generated in the identification information generation step, and holding the identification information and the reproduction reference information generated in the identification information generation step each time a transport stream is received. Knowledge stored in association with each step It compares the information, to execute a content reproduction step for reproducing content by using the playback reference information according to the comparison result.

  According to the present invention, it is possible to reproduce an unspecified number of contents distributed by MPEG2 via broadcast or a network without taking time.

  First, an embodiment of the present invention will be described with reference to the drawings. The embodiments described below are preferred embodiments of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. Unless otherwise stated, the present invention is not limited to these embodiments.

  First, the configuration of the information processing apparatus according to the embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a diagram illustrating a hardware configuration of the information processing apparatus according to the present embodiment. The information processing apparatus of the present embodiment is a client 20 that receives MPEG2-TTS 8 from a server 10 that distributes content via a network 9. The client 20 includes a receiving unit 21, a splitter 22, a reproduction reference information recording unit 23, a decoder 24, and an AV output unit 25, and further includes a control unit (not shown). The server 10 includes a TS data storage unit 11 and a transmission unit 12. In the present embodiment, for example, a home server that distributes content recorded by a video camera will be described as an example of receiving a transport stream via a network. As another embodiment, a channel broadcast from a broadcasting station is described. And the case of receiving a channel by inputting a URL in IPTV.

  First, the hardware configuration of the server 10 will be described. The TS data storage unit 11 stores content to be distributed and holds it in the MPEG2-TS format. The transmission unit 12 transmits a transport stream that constitutes the content selected by the client 20. The TS data storage unit 11 may hold the content in the MPEG2-PS format. In this case, the transmission unit 12 converts the content into the MPEG2-TS format and transmits it.

  Next, the hardware configuration of the client 20 will be described. The receiving unit 21 receives the MPEG2-TTS 8 transmitted from the server 10 via the network 9 and sends it to the splitter 22. The splitter 22 analyzes the transport stream received from the receiving unit 21, acquires the reproduction reference information necessary for reproducing the content, and sends the transport stream and the reproduction reference information to the decoder. Further, the splitter 22 generates a hash value by using a part of TS packets (TS packet including PAT) in the transport stream, and associates the reproduction reference information acquired by the analysis with the hash value, and a reproduction reference information recording unit 23. Although details will be described later, every time the splitter 22 receives the transport stream, the splitter 22 generates a hash value from the TS packet including the PAT, and searches the reproduction reference information recording unit 23 for a matching hash value. The decoder 24 decodes TS packets (Video, Audio, etc.) constituting the desired content using the reproduction reference information held in the recording unit 23 or the reproduction reference information obtained by analysis. The AV output unit 25 performs external output of Video and Audio decoded by the decoder 24. In this embodiment, the splitter 22 is provided with functions for generating a hash value, searching for a hash value, and analyzing a transport stream. It is also possible to configure so that functions are provided in separate hardware.

  FIG. 2 is a diagram illustrating functional blocks of the information processing apparatus according to the present embodiment. The control unit 1 logically includes an identification information generating unit 2, a stream analyzing unit 3, a reproduction reference information holding unit 4, and a content reproducing unit 5. That is, the identification information generation means 2 has a function corresponding to the identification information generation means described in the claims, the stream analysis means 3 has a function corresponding to the stream analysis means described in the claims, and the reproduction reference information holding means 4 has the function. The content reproduction means 5 has a function corresponding to the content reproduction means described in the claims, and the content reproduction means 5 has a function corresponding to the content reproduction means described in the claims.

  The feature of the present invention is that reproduction reference information necessary for content reproduction is stored in association with each other, and a hash value is generated every time a transport stream is received, and the reproduction reference information is stored in the hash value as a key. Is used for content reproduction. Here, the reproduction reference information is held in association with a hash value obtained by hashing some TS packets in the transport stream. Some TS packets are TS packets including a PAT, and in this embodiment, three packets after the PAT are used as shown in FIG. The TS packet for which the hash value is generated may be a single PAT, and the number of packets including the PAT is set to increase the accuracy of identity determination. Further, the range of TS packets for which a hash value is to be generated can be arbitrarily set such as 3 packets after PAT, 3 packets (PAT + 1 packet before and after PAT), and 3 packets before PAT.

  The reason why PAT is included in the object of hashing is as follows. In general, it is known that the specification of an encoder differs depending on each distribution device or recording device. Therefore, the binary configuration around the PAT and the value of PID tend to be roughly determined in each device. This is probably because the MPEG2-TS standard allows a wide range of discretion so that data is created after the range of use of the standard is defined as a rule for each encoder and broadcast specification. Therefore, a binary configuration around the PAT that is different for each device (encoder) can be used as information for identifying a transport stream. For example, if a hash value is obtained from the binary around the PAT, a unique value is obtained for each device (encoder). Hashing is employed to compress the amount of data and increase the search speed, and other techniques may be used as long as these objects are achieved.

  Next, a content reproduction operation performed by the information processing apparatus according to the present embodiment will be described with reference to FIGS. FIG. 3 is a diagram for explaining the content reproduction operation in the present embodiment. In the first reproduction, the received MPEG2-TTS is analyzed as usual to obtain reproduction reference information, and decoding processing and AV output processing are performed. In addition, the obtained reproduction reference information is associated with identification information in a recording unit (FIG. 1). Are stored in the reproduction reference information recording unit 23). That is, as shown in FIG. 3A, a PAT is extracted from the received MPEG2-TTS, and a hash value is generated for three packets from the PAT (1). On the other hand, reproduction reference information is acquired by analyzing MPEG2-TTS (2). Then, the reproduction reference information obtained by the analysis is recorded in the recording unit in association with the hash value (3). Then, using the obtained reproduction reference information, the TS packet (Video, Audio) constituting the desired content is specified from the MPEG2-TTS, and the decoding process is performed (4). Then, external output of the decoded Video and Audio is performed (5). The operations of (1) to (3) are performed by the splitter 22 (FIG. 1), the operation of (4) is performed by the decoder 24 (FIG. 1), and the operation of (5) is performed by the AV output unit 25 (FIG. 1). .

  Note that the reproduction reference information is information necessary for reproduction of the content. As shown in FIG. 4, the PMT PID value, the Video PID value, the Audio PID value, the Video format (MPEG2-PS, H264), and the sequence header Information, Audio format (AC3, AAC), and WAVEFORMAT information.

  Since the reproduction reference information is not stored in the recording unit in the first reproduction, the reproduction reference information is recorded without searching the recording unit. However, in the second and subsequent reproductions, the reproduction reference information is stored in the recording unit. Therefore, search using the hash value as a key. That is, a hash value is generated using three packets from the received MPEG2-TTS PAT (11), and a matching hash value is searched from the recording unit (12). When a matching hash value is found, the reproduction reference information associated with the searched hash value is read and used for the decoding process (14). On the other hand, the received MPEG2-TTS is analyzed in parallel with the generation of the hash value to obtain reproduction reference information (13). When a matching hash value is not found in the search operation, the reproduction reference information obtained by the analysis is used for decoding and stored in the recording unit in association with the hash value (15). Also, when a matching hash value is found and decoding processing is started using the reproduction reference information of the recording unit, but the reproduction reference information obtained by the analysis performed at the same time is different from the reproduction reference information of the recording unit Updates the reproduction reference information obtained by the analysis by overwriting (16).

  FIG. 5 is a flowchart showing the flow of content reproduction operation in the present embodiment. First, MPEG2-TTS is received by the receiving unit 21 (FIG. 1) (step S101). Next, the identification information generating means 2 (FIG. 2) hashes the three packets after the PAT and calculates a hash value (step S102). Hashing is performed every time MPEG2-TTS is received. Next, the MPEG2-TTS is analyzed in parallel with hashing by the stream analysis means 3 (FIG. 2) to obtain reproduction reference information (step S103). The analysis of MPEG2-TTS is performed every time MPEG2-TTS is received regardless of the hash value search result described later.

  When obtaining the hash value, the arrival information (ATS) of the first 4 bytes is removed from the three TTS packets. This is because even if the distribution data is from the same device, a different value (packet arrival time) is added for each distribution, so that the hash value is different and cannot be used for transport stream identification.

  When the flow returns, the content reproduction means 5 (FIG. 2) uses the calculated hash value to search the data (hash value associated with the reproduction reference information) stored in the reproduction reference information recording unit 23 (FIG. 1). (Step S104). When a matching hash value is found (step S105 / YES), reproduction reference information associated with the searched hash value is read from the recording unit, and decoding processing is started using MPEG2-TTS and reproduction reference information. (Step S106).

  Further, the reproduction reference information analyzed in parallel with the hashing is acquired by the stream analysis unit 3 (step S107), and the reproduction reference information acquired by the analysis and the reproduction reference information being used in the decoding process are acquired by the content reproduction unit 5. Comparison is performed (step S108). When both reproduction reference information is the same (step S109 / YES), the decoding process is continued (step S110), but when both are different (step S109 / NO), the decoding is stopped and the reproduction reference obtained by the analysis is obtained. The decoding process is started using the information (step S111), and the acquired reproduction reference information is overwritten to update the data of the reproduction reference information recording unit 23 (step S112).

  On the other hand, if a matching hash value is not found in the search of the data stored in the reproduction reference information recording unit 23 (step S105 / NO), the reproduction reference information analyzed in parallel with the hashing by the stream analysis unit 3 (Step S113), the reproduction reference information holding means 4 (FIG. 2) stores the reproduction reference information in the reproduction reference information recording unit 23 in association with the hash value (step S114). Then, decoding processing is started using the reproduction reference information acquired by analysis (step S115).

  According to the above-described embodiment, the reproduction reference information obtained by analyzing the transport stream as usual is stored, and the reproduction reference information stored in the reproduction of the stream data distributed from the same device is used. The contents of the channel once received can be reproduced without taking time from the second time.

  In addition, according to the above-described embodiment, a hash value is generated for a TS packet including a PAT of a transport stream, and reproduction reference information is held using the hash value. Therefore, reproduction reference is associated with each device (encoder). Information can be used. At this time, by adopting hashing, the amount of data to be recorded can be compressed, and the data search process can be speeded up. Also, the data amount can be reduced as compared with the case where the reproduction reference information is stored for each content.

  The above-described embodiment is a preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiment alone, and various modifications are made without departing from the gist of the present invention. Implementation is possible.

  That is, the program executed by the information processing apparatus according to the present embodiment has a module configuration including the above-described units (identification information generation unit, stream analysis unit, reproduction reference information holding unit, content reproduction unit). Specific means are realized by using actual hardware. That is, when the computer (CPU) reads out and executes a program from a predetermined recording medium, the above-described units are loaded onto the main storage device, and the identification information generating unit, the stream analyzing unit, the reproduction reference information holding unit, and the content reproduction unit Are generated on the main memory.

  The program executed by the information processing apparatus in the present embodiment may be configured to be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. Further, the program may be provided or distributed via a network such as the Internet.

  The program is a file in an installable or executable format, such as a floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, DVD, nonvolatile memory card, or the like. It may be configured to be provided by being recorded on a computer-readable recording medium. Further, the program may be provided by being incorporated in advance in a ROM or the like.

  In this case, the program code itself read from the recording medium or loaded and executed through the communication line realizes the functions of the above-described embodiments. And the recording medium which recorded the program code comprises this invention.

It is a hardware block diagram of an information processor concerning an embodiment of the present invention. It is a functional block diagram of a control part of an information processor concerning an embodiment of the present invention. It is a figure for demonstrating the content reproduction operation | movement in embodiment of this invention. It is a figure for demonstrating the information required for reproduction | regeneration of the content comprised by MPEG2. It is the flowchart which showed the flow of the content reproduction | regeneration operation | movement in embodiment of this invention. It is a figure for demonstrating the reproduction | regeneration method in the past of the content comprised by MPEG2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control part 2 Identification information production | generation means 3 Stream analysis means 4 Reproduction | regeneration reference information holding means 5 Content reproduction means 8 MPEG2-TTS
9 Network 10 Server 11 TS Data Storage Unit 12 Transmission Unit 20 Client 21 Reception Unit 22 Splitter 23 Playback Reference Information Recording Unit 24 Decoder 25 AV Output Unit

Claims (8)

  When reproducing the content by receiving the encoded stream data, a part of the received stream data is used to associate the reproduction reference information referred to during content reproduction with the information obtained by analyzing the stream data. The information processing is characterized in that when the stream data is held and the stream data is newly received, the comparison is performed using a part of the stream data, and the content is played back using the held playback reference information according to the comparison result. apparatus.   The information processing apparatus according to claim 1, wherein the stream data is a transport stream, and a part of the stream data is a TS packet including a PAT.   When the comparison result is the same, the content is reproduced using the held reproduction reference information for the newly received stream data, and when the comparison result is different, the newly received stream data is received 3. The reproduction reference information acquired by analyzing stream data is held in association with each other, and the content is reproduced using the acquired reproduction reference information for the stream data. Information processing device. An information processing apparatus that receives an encoded transport stream and reproduces content,
Identification information generating means for generating identification information using a TS packet including a PAT in the received transport stream;
Stream analysis means for analyzing the received transport stream and obtaining reproduction reference information referred to during content reproduction;
Reproduction reference information holding means for holding the reproduction reference information acquired by the stream analysis means in association with the identification information generated by the identification information generation means;
Each time a transport stream is received, the identification information generated by the identification information generating means is compared with the identification information held in association with the reproduction reference information holding means, and the reproduction reference information is used according to the comparison result. Content playback means for playing back content,
An information processing apparatus comprising:   The content reproduction means reproduces the content using the reproduction reference information held by the reproduction reference holding means for the received transport stream when both identification information is the same in the comparison, The content is reproduced using the reproduction reference information newly analyzed by the stream analysis means for the transport stream when both identification information is different in the comparison. Information processing device. The content reproduction means reproduces the content using the reproduction reference information held in the reproduction reference holding means for the received transport stream when both identification information is the same in the comparison,
The stream analyzing means analyzes the received transport stream and obtains reproduction reference information simultaneously with the content reproduction,
The reproduction reference information holding means, when the reproduction reference information associated with the identification information already held is different from the reproduction reference information acquired by the stream analysis means, the acquired reproduction reference information The information processing apparatus according to claim 4, wherein the information processing apparatus is used and updated.   The information processing apparatus according to claim 4, wherein the identification information generation unit generates identification information by excluding time information of a packet from a TS packet including the PAT. A program used in an information processing apparatus that receives an encoded transport stream and reproduces content,
On the computer,
An identification information generating step of generating identification information using a TS packet including a PAT in the received transport stream;
A stream analysis step of analyzing the received transport stream to obtain reproduction reference information referred to during content reproduction;
A reproduction reference information holding step for holding the reproduction reference information acquired in the stream analysis step in association with the identification information generated in the identification information generation step;
Each time a transport stream is received, the identification information generated in the identification information generation step is compared with the identification information held in association with the reproduction reference information holding step, and the reproduction reference information is used according to the comparison result. Content playback step for playing back content,
A program characterized by having executed.

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