JP2010245756A - Communication network system, method of reproducing content, and server - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that, in a conventional chunk method, a content cannot be continuously reproduced without applying large loads on a reproduction device and a server nor causing disturbance in an image or a sound at a discontinuous point. <P>SOLUTION: This communication network system includes: a server 100 configured to transmit, by a chunk method, a first content, and a second content reproduced based on a reproduction time of a reference position of the first content, and having a form different from that of the first content, and also transmit the information of the difference between a reproduction time of the rear end of the first content and that of the tip of the second content, and the information of the form of the second content; and a reproduction device 200 configured to receive data from the server 100, and continuously reproduce the first content and the second content using the information of the difference between the reproduction times and the information of the form of the second content. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a technology for transmitting and reproducing content via a communication network.

  Content in which image or audio data is compressed by MPEG or the like is composed of a plurality of packets, and the header of all or part of the packet includes a time stamp indicating the reproduction time of the packet. The playback device plays back the content continuously by playing back each packet with reference to the time stamp.

  The header also includes attribute information such as information (resolution information) indicating the resolution of the content included in the packet and information (format information) indicating the format.

  However, time stamps and attribute information may become discontinuous due to content editing or the like. For example, when editing is performed to cut halfway through the original content consisting of a two-hour moving image, the time before and after the cut portion skips by 30 minutes, and the time stamp becomes discontinuous. In addition, when editing is performed to reduce the resolution without cutting the middle 30 minutes, the resolution information is discontinuous between the 30-minute content and the content before and after that content.

  If such a content having discontinuous points is reproduced as it is, the image or sound may be disturbed at the discontinuous points.

  Normally, the playback device stores information on discontinuities that occur when content is edited, and when the edited content is played back, the above-described image or Prevents audio disturbance.

  By the way, a system in which a server and a playback device are connected via a network, and the playback device receives and plays back content stored in the server via the network is now widely used. In such a system, the information on the discontinuous points is stored in the server, and the playback device cannot use the information on the discontinuous points. Accordingly, when the playback apparatus plays back content having discontinuous points supplied from the server, there is a problem that the image or sound may be disturbed at the discontinuous points.

  In order to solve the above problem, for example, in Patent Document 1, a playback device designates a whole or a partial area of content, and a message for inquiring the range of a part (continuous area) in which the time stamp continues in the area. By continuously transmitting to the server according to a predetermined communication protocol and repeatedly transmitting a message specifying the range of the continuous area to the playback device according to the predetermined communication protocol, only the continuous area is reproduced without interruption. A method is disclosed.

JP 2005-260283 A

  However, the reproduction method disclosed in Patent Document 1 has a problem that a large load is applied to the reproduction apparatus and the server because the reproduction apparatus repeatedly inquires the server.

  The present invention has been made in view of the above-described problems, and can continuously play back content without causing disturbances in images and sound at discontinuous points without imposing a heavy load on the playback device and server. An object of the present invention is to provide a communication network system, a content reproduction method, and a server.

  In order to solve the above problems and achieve the above object, the communication network system according to the present invention uses the HTTP chunk method in which the information on the length of the content to be transmitted and the content are inserted into the response body and transmitted. And the second content that is reproduced with reference to the reproduction time at the reference position of the first content and has a different form from the first content, and after the first content A server that also transmits information on the difference in playback time between the end and the tip of the second content, and information on the form of the second content, the first content from the server, and the first content 2 contents, information on the difference between the reproduction times, and information on the form of the second content, and information on the differences between the reproduction times and the second content. Of using a form of information, and a reproducing apparatus for continuously reproducing the first content and the second content.

  In the content playback method of the present invention, the server uses the HTTP chunk method in which the length information of the content to be transmitted and the content are inserted into the response body and transmitted, and the first content and the content of the first content are transmitted. The second content that is reproduced with reference to the reproduction time at the reference position and is different in form from the first content is transmitted, and the rear end of the first content and the front end of the second content The information on the difference in reproduction time and the information on the form of the second content are also transmitted, and the reproduction device receives the first content, the second content, and the reproduction time from the server. Receiving the difference information and the second content type information, and using the reproduction time difference information and the second content type information, Play of content and the second content sequentially.

  The server according to the present invention uses the HTTP chunk method in which the length information of the content to be transmitted and the content are inserted into the response body and transmitted, thereby reproducing the first content and the reproduction time of the reference position of the first content. And the second content having a form different from that of the first content is transmitted, and the difference in reproduction time between the rear end of the first content and the front end of the second content is transmitted. Information and information in the form of the second content are also transmitted.

  According to the present invention, it is possible to continuously play back content without causing disturbances in images and sound at discontinuous points without imposing a heavy load on the playback device and the server.

1 is a configuration diagram of a communication network system according to a first embodiment. 5 is a diagram for describing content of the first embodiment. FIG. It is a figure which shows the sequence of transmission / reception of the data between a server and a reproducing | regenerating apparatus. 3 is a flowchart illustrating steps of operations of the server and the playback device according to the first embodiment. It is a figure which shows the request header which requests | requires the start of the reproduction | regeneration of the content from the middle of the content. It is a block diagram of the communication network system which processes invalid data. FIG. 3 is a configuration diagram of a communication network system according to a second embodiment. 10 is a flowchart illustrating steps of operations of the server and the playback device according to the second embodiment. FIG. 10 is a diagram for illustrating content of a second embodiment.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated with reference to drawings.

(Embodiment 1)
First, the configuration of the communication network system according to the first embodiment will be described with reference to FIG.

  FIG. 1 is a configuration diagram of a communication network system according to the first embodiment. The communication network system according to Embodiment 1 is a system that transmits and reproduces content via a communication network, and includes a server 100 and a reproduction device 200 as shown in FIG. The device 200 is connected to the communication network 300.

  In response to a request from the playback apparatus 200, the server 100 uses the chunk method for transmitting the length information of the data to be transmitted and the data to the content held by the server 100 via the communication network 300. 200, a transmission side request communication unit 101, a storage unit 102, a division unit 103, a discontinuous information addition unit 104, and a content transmission unit 105.

  The transmission side request communication unit 101 responds to a request for a communication session from the playback apparatus 200. The storage unit 102 stores content A. The content A will be described later with reference to FIG. The dividing unit 103 divides the content A into a plurality of chunks (hereinafter referred to as “continuous regions”). When the continuous area to be transmitted is discontinuous with the previously transmitted continuous area, the discontinuous information adding unit 104 adds discontinuous information to the continuous area to be transmitted. The content transmission unit 105 transmits a plurality of continuous areas constituting the content A to the playback device 200 via the communication network 300.

  The playback device 200 is a device that receives and plays back content from the server 100, and includes a reception-side request communication unit 201, a content reception unit 202, a discontinuous information analysis unit 203, a decoding unit 204, and an output unit. 205. Although not displayed in FIG. 1, the playback device 200 is connected to an output device such as a display device or a speaker.

  The receiving side request communication unit 201 obtains a communication session to the server 100. The content receiving unit 202 receives content from the server 100. When the discontinuous information is added to the content received by the content receiving unit 202, the discontinuous information analyzing unit 203 analyzes the discontinuous information. The decoding unit 204 decodes the content received by the content receiving unit 202. The output unit 205 outputs the content decrypted by the decoding unit 204 to an output device connected to the playback device 200.

  Next, the data structure of HTTP (Hyper Text Transfer Protocol) used for transmission and reception in the first embodiment will be described with reference to FIG.

  The content A shown in FIG. 2A is, for example, a movie broadcast between the position of 30 minutes to 40 minutes from the beginning of the original content and the position of 1 hour to 1 hour 10 minutes from the beginning. It is a content such as the inside news, weather forecast, etc., which is a discontinuous part and is edited so that the part is cut. That is, as shown in FIG. 2A, the content A according to the first embodiment includes a continuous area P1 at a position 30 minutes from the beginning to the beginning and a continuous area 40 minutes to a position 1 hour from the beginning. There are three continuous regions, P2 and a continuous region P3 at a position of 1 hour and 10 minutes to a position of 2 hours from the beginning.

  In each of the continuous region P1, the continuous region P2, and the continuous region P3, the time stamp (reproduction time) value is continuous, but the time stamp value at the rear end of the continuous region P1 and the leading end of the continuous region P2 The time stamp value of is not continuous. Further, the time stamp value at the rear end of the continuous area P2 and the time stamp value at the front end of the continuous area P3 are not continuous. That is, the value of the time stamp is discontinuous between the continuous region P1 and the continuous region P2 and between the continuous region P2 and the continuous region P3. It should be noted that for each packet of the continuous area P1, the continuous area P2, and the continuous area P3, the playback time is based on the time stamp value included in the packet at the reference position (for example, the head) of the continuous area P1. A value that identifies is included.

  FIG. 2B shows a data structure in the case where content A having discontinuities as described above is transmitted by the conventional batch transmission method in HTTP. In the response header (RESPONSE HEADER), Content-Length information indicating the entire size of the content A is inserted, and in the response body (RESPONSE BODY), continuous areas P1, P2, and P3 are inserted in a lump. Therefore, in this method, information on discontinuous points (hereinafter referred to as “discontinuous information”) is lost, and therefore, there is a high possibility that the image and the sound are disturbed when played back by the playback device.

  FIG. 2C shows a data structure of a transmission method used in the first embodiment. This transmission method is an improvement over the Chunked method, which is one of HTTP data transfer methods. The Chunked method is a data transfer method used when the overall size of the content to be transmitted is unknown. In the Chunked method, Transfer-Encoding information for indicating that the transfer method is the Chunked method is inserted in the response header instead of the Content-Length information. Then, the content to be transmitted is divided, and each size of the divided content is added to the head portion of the corresponding divided content in the response body.

  The transmission method used in the first embodiment is characterized in that discontinuous information is added in addition to the size as information added to the head portion of the divided content.

  In FIG. 2C, Size <1>, Size <2>, Size <3>, and Size <n> added to the leading portions of the continuous regions P1, P2, and P3 are the sizes in the conventional Chunked system. Information, and PTS_offset written in Size <2> and Size <3> is the discontinuous information added in the first embodiment.

  Next, the operation of the communication network system according to the first embodiment will be described with reference to FIGS.

  FIG. 3 is a diagram illustrating a data transmission / reception sequence between the server 100 and the playback device 200. HTTP is used for data transmission / reception between the server 100 and the playback apparatus 200. FIG. 4 is a flowchart showing steps of the operations of the server 100 and the playback device 200 according to the first embodiment. In the following description, FIG. 4 is mainly used.

  First, the receiving side request communication unit 201 of the playback device 200 transmits a request header to the server 100 in order to request the content A stored in the server 100 (S1). As shown in FIG. 2C, the request header is an HTTP request message including a GET method, and includes a URI designating “movie.mpg” indicating the content A.

  In the server 100, the transmission side request communication unit 101 receives the request header from the playback device 200, and transmits a response header to the playback device 200 in response to the request header (S2). 201 receives a response header from the server 100 (S3). Thereby, a session between the server 100 and the playback device 200 is established.

  In the reproduction method disclosed in Patent Document 1, the exchange of the request header and the response header is repeated, but in the first embodiment, the exchange of the request header and the response header is performed only once. Therefore, in the content reproduction method according to the first embodiment, the load on the server 100 and the reproduction apparatus 200 is reduced as compared with the reproduction method disclosed in Patent Document 1.

  In the server 100, when the response header is transmitted to the playback device 200 (S2), the dividing unit 103 divides the content A stored in the storage unit 102 into discontinuous parts (S4). Since the content A has two discontinuous portions as shown in FIG. 2A, the dividing unit 103 first converts the content A from the beginning of the content A to the first discontinuous point. The continuous area P1 and the first discontinuous point to the tail of the content A are divided (S4).

  Since the continuous area P1 is data transmitted first, the discontinuous information adding unit 104 does not add discontinuous information to the continuous area P1 (S5), and the content transmitting unit 105 determines the size of the continuous area P1. The data is transmitted to the playback device 200 via the communication network 300 (S6). Specifically, using FIG. 2C, the content transmission unit 105 first transmits “526C00 (hexadecimal number)” indicating the size (Size <2>) of the continuous area P1 to the playback device 200, Next, the data of the continuous area P1 is transmitted.

  Next, the dividing unit 103 checks whether or not the transmission of the content A is completed (S7), and determines that the transmission of the content A is not completed at the stage where the continuous area P1 is transmitted (No in S7). The operation of the server 100 returns to step S4.

  The dividing unit 103 divides the remaining part of the content A into a continuous region P2 from the first discontinuous point of the content A to the second discontinuous point, and from the second discontinuous point to the tail of the content A (S4). The discontinuity information adding unit 104 determines the difference between the reproduction time (time stamp) at the rear end of the continuous area P1 and the reproduction time at the front end of the continuous area P2 (hereinafter, also referred to as “first reproduction time difference”). As discontinuity information, it is added to the size information of the continuous area P2 (S5). The difference in the first reproduction time is “PTS_Offset = 60000” in the size information “36EE800; PTS_Offset = 60000” described before the continuous area P2 in FIG. 2C, which is discontinuous. The time stamp difference (10 minutes = 60000 milliseconds). The difference in the first reproduction time is used as an offset value in the reproduction apparatus 200.

  The content transmission unit 105 sends the size information including the size of the continuous area P2 (Size <2>) and the difference between the first reproduction times and the data of the continuous area P2 to the reproduction apparatus 200 via the communication network 300. Transmit (S6). Specifically, using FIG. 2C, the content transmission unit 105 indicates the difference between “36EE800 (hexadecimal number)” indicating the size (Size <2>) of the continuous area P2 and the first reproduction time. The size information “36EE800; PTS_Offset = 60000” combined with “PTS_Offset = 60000” is transmitted to the playback device 200, and then the data of the continuous area P2 is transmitted.

  Next, the dividing unit 103 checks whether or not the transmission of the content A is completed (S7), and determines that the transmission of the content A is not completed at the stage where the continuous area P2 is transmitted (No in S7). The operation of the server 100 returns to step S4 again.

  The dividing unit 103 sets the rest of the content A as the continuous area P3 (S4), and the discontinuous information adding unit 104 determines the difference between the playback time at the rear end of the continuous area P2 and the playback time at the front end of the continuous area P3 (hereinafter, (Also referred to as “second playback time difference”) is added as discontinuity information to the size information of the continuous region P3 (S5). The difference in the second reproduction time is “PTS_Offset = 60000” in the size information “8954400; PTS_Offset = 60000” described before the continuous area P3 in FIG. 2C, which is discontinuous. The time stamp difference (10 minutes = 60000 milliseconds). The difference in the second reproduction time is also used as an offset value in the reproduction apparatus 200.

  The content transmission unit 105 sends the size information including the size of the continuous area P3 (Size <3>) and the second playback time difference and the data of the continuous area P3 to the playback device 200 via the communication network 300. Transmit (S6). Specifically, using FIG. 2C, the content transmission unit 105 indicates the difference between “8954400 (hexadecimal number)” indicating the size (Size <3>) of the continuous region P3 and the second reproduction time. The size information “8954400; PTS_Offset = 60000” combined with “PTS_Offset = 60000” is transmitted to the playback device 200, and then the data of the continuous area P3 is transmitted.

  Next, the dividing unit 103 checks whether or not the transmission of the content A is completed (S7), determines that the transmission of the content A is completed when the continuous area P3 is transmitted (Yes in S7), and the content In order to indicate that the transmission of the content A is completed, the transmission unit 105 transmits size information in which the size of the continuous area to be transmitted thereafter is “0” (Size <n>) via the communication network 300. 200 (S8). Thereby, the operation of the server 100 ends.

  In the playback apparatus 200, the content receiving unit 202 receives the continuous area P1 from the server 100 (S9), and confirms that the size “0” indicating that the transmission of the content A has been completed has not been transmitted ( No in S10), the discontinuity information analysis unit 203 determines whether or not discontinuous information is included in the continuous area P1 (S11). Since the discontinuous information is not included in the continuous area P1 (No in S11), the decoding unit 204 decodes the continuous area P1 (S13), and the output unit 205 outputs the decoded continuous area P1 to the playback device 200. To an external output device (S14).

  Next, the operation of the playback device 200 returns to step S9, and the content receiving unit 202 receives the continuous area P2 from the server 100 (S9), and transmits a size “0” indicating that the transmission of the content A has ended. It is confirmed that no discontinuity information has been received (No in S10), and the discontinuity information analysis unit 203 determines whether discontinuous information is included in the continuous region P2 (S11). Since the difference between the reproduction time at the rear end of the continuous area P1 and the reproduction time at the front end of the continuous area P2 (first reproduction time difference) is added to the continuous area P2, the discontinuous information analysis unit 203 Then, it is confirmed that the time stamp has jumped 10 minutes from the rear end of the continuous area P1 to the front end of the continuous area P2, and an offset process is performed (S12). That is, the discontinuity information analysis unit 203 notifies the decoding unit 204 to subtract the first reproduction time difference from the time stamp added to each packet constituting the continuous area P2 (S12).

  The decoding unit 204 decodes the continuous region P2 by subtracting the first reproduction time difference from the time stamp added to each packet constituting the continuous region P2 (S13), and the output unit 205 outputs the decoded continuous data The region P2 is output to an output device external to the playback device 200 (S14).

  Since the offset processing is performed by the discontinuity information analysis unit 203 (S12), the decoding unit 204 and the output unit 205 reproduce the continuous region P1 and the continuous region P2 without interruption.

  Next, the operation of the playback apparatus 200 returns to step S9 again, and the content receiving unit 202 receives the continuous area P3 from the server 100 (S9), and the size “0” indicating that the transmission of the content A has ended is set. It is confirmed that the information has not been transmitted (No in S10), and the discontinuous information analysis unit 203 determines whether or not the discontinuous information is included in the continuous region P3 (S11).

  Since the difference between the reproduction time at the rear end of the continuous area P2 and the reproduction time at the front end of the continuous area P3 (second reproduction time difference) is added to the continuous area P3 (Yes in S11), discontinuity is generated. The information analysis unit 203 recognizes that the time stamp has jumped 10 minutes from the rear end of the continuous area P1 to the front end of the continuous area P2, and performs offset processing (S12). That is, the discontinuity information analysis unit 203 notifies the decoding unit 204 to subtract the second reproduction time difference from the time stamp added to each packet constituting the continuous region P3 (S12).

  The decoding unit 204 decodes the continuous region P3 by subtracting the second reproduction time difference from the time stamp added to each packet constituting the continuous region P3 (S13), and the output unit 205 outputs the decoded continuous data The region P3 is output to an output device external to the playback device 200 (S14).

  Since the offset processing is performed by the discontinuity information analysis unit 203 (S12), the decoding unit 204 and the output unit 205 reproduce the continuous region P2 and the continuous region P3 without interruption.

  Next, the operation of the playback apparatus 200 returns to step S9 again, and the content receiving unit 202 receives the continuous area P3 from the server 100 (S9), and the size “0” indicating that the transmission of the content A has ended is set. It is confirmed that it has been transmitted (Yes in S10). As a result, the operation of the playback device 200 ends.

  As described above, in the communication network system according to the first embodiment, server 100 transmits when the playback time at the front end of the continuous area to be transmitted and the playback time at the rear end of the previous continuous area are discontinuous. Before transmitting the target continuous area, information on the difference in playback time between the rear end of the previous continuous area and the front end of the continuous area to be transmitted is also transmitted. Using the difference information, the two continuous areas are reproduced continuously without interruption. In the communication network system of the first embodiment, the request header and response header are exchanged only once.

  Therefore, according to the communication network system of the first embodiment, the load applied to the playback device 200 and the server 100 is reduced, and the next playback is performed based on the playback time of a certain continuous area and the reference position of the continuous area. It is possible to obtain the effect of continuous reproduction without interruption from the continuous region.

  In addition, when reproducing | regenerating apparatus 200 reproduces | regenerates by performing decoding initialization and reproducing | regenerating, when reproducing | regenerating the latter continuous area | region of two adjacent continuous areas, it is continuous, without interrupting two adjacent continuous areas. May be played.

  Further, when the playback device 200 tries to start playback of the content from the middle of the content, the playback header 200 includes the RANGE header 51 in the request header 50 and designates the playback start position, as shown in FIG. In FIG. 5, “RANGE: 8634000-” indicates the reproduction start position. When the RANGE header is included in the request header, the transmission side request communication unit 101 of the server 100 includes the transmission target in the response header. A Content-RANGE header that specifies the data range is included.

  By the way, invalid data that cannot be reproduced by the reproduction apparatus 200 may be included in the continuous area reproduced by the server 100. In this case, the server 100 transmits the position of invalid data in the continuous area to the playback device 200 in order to increase the speed of playback of the continuous area. That is, as illustrated in FIG. 6, the server 100 reproduces invalid data position specifying unit 110 that specifies the position of invalid data and invalid information that indicates the position of invalid data specified by the invalid data position specifying unit 110. 200, an invalid information adding unit 111 for notifying 200 is included. The invalid information adding unit 111 adds invalid information to the size information transmitted by the content transmitting unit 105. When invalid data is included in the continuous area P1, the invalid information is included in the size information of the continuous area P1, for example, “17700; unless_1frame”. The invalid data is data that cannot constitute one moving image, for example.

  The server 100 can also perform an operation that does not transmit invalid data, but this may not correspond to a request that the playback device 200 makes to the server 100. Therefore, the server 100 transmits invalid data.

  The playback apparatus 200 includes an invalid information analysis unit 210 that analyzes invalid information. The invalid information analysis unit 210 analyzes invalid information received by the content reception unit 202, and the decoding unit 204 is based on the analysis result. Then, invalid data is skipped, and valid data that can be reproduced is decoded. As a result, the playback speed of the content A, specifically, the continuous area P1, the continuous area P2, and the continuous area P3 can be increased. The invalid data may be all of the continuous area P1, the continuous area P2, or the continuous area P3.

(Embodiment 2)
Next, a communication network system according to the second embodiment will be described. Since the second embodiment and the first embodiment have many overlapping portions, the second embodiment will focus on portions that are different from the portions described in the first embodiment.

  FIG. 7 is a configuration diagram of the communication network system according to the second embodiment. As shown in FIG. 7, the server according to the second embodiment includes a content generation unit 120 that generates real-time content in addition to the components included in the server 100 according to the first embodiment. The content generation unit 120 is, for example, a tuner that receives content in real time, a transcoder that converts the resolution of the content A stored in the storage unit 102 to a different resolution. In order to simplify the description, in the following, it is assumed that the content generation unit 120 is a tuner, and the content output from the content generation unit 120 is content B.

  FIG. 8 is a flowchart illustrating steps of operations of the server 100 and the playback device 200 according to the second embodiment. FIG. 9 is a diagram showing the content B to be played back.

  The content received by the content generation unit 120 includes a CM, or when the form of the content such as the resolution and format of the moving image changes midway due to switching from one program to the next program, etc. Assume.

  Hereinafter, operations of the server 100 and the playback device 200 according to the second embodiment will be described with reference to FIG.

  First, the receiving side request communication unit 201 of the playback apparatus 200 transmits a request header to the server 100 in order to request the content B from the server 100 (S21). The request header is an HTTP request message including a GET method, and includes a URI designating “tuner.mpg” indicating the content B.

  In the server 100, the transmission side request communication unit 101 receives the request header from the playback device 200, and transmits a response header to the playback device 200 in response to the request header (S22). 201 receives a response header from the server 100 (S23). Thereby, a session between the server 100 and the playback device 200 is established.

  In the server 100, when the transmission side request communication unit 101 transmits a response header to the playback device 200 (S22), the dividing unit 103 acquires a part of the content B from the content generation unit 120 (S24), and the resolution is included therein. It is determined whether or not there is a discontinuous portion having a different form of content such as or format (S25). When the dividing unit 103 determines that there is a discontinuous part having a different form in a part of the acquired content B (Yes in S25), the dividing unit 103 divides the content B by a part having a discontinuous form (S26). The discontinuity information adding unit 104 adds information on the form (resolution or format) of the continuous area P11 to the size information of the continuous area P11 from the beginning of the content B to the first discontinuous part (S27). The content transmission unit 105 transmits the size information of the continuous area P11 including the size of the continuous area P11 and the form of the continuous area P11 to the playback apparatus 200, and then transmits the data of the continuous area P11 to the playback apparatus 200 (S28). ).

  Next, the dividing unit 103 checks whether or not the transmission of the content B is completed (S29). If the dividing unit 103 determines that the transmission of the content B is not completed (No in S29), the operation of the server 100 is performed in step S24. Return to. On the other hand, when the dividing unit 103 determines that the transmission of the content B has been completed (Yes in S29), the content transmitting unit 105 indicates the continuous area to be transmitted thereafter to indicate that the transmission of the content B is finished. The size information with the size set to “0” is transmitted to the playback device 200 (S30). Thereby, the operation of the server 100 ends.

  When the dividing unit 103 determines that the transmission of the content B has not been completed and the operation returns to step S24, the dividing unit 103 acquires a part of the content B from the content generating unit 120, and includes the resolution and It is determined whether there is a discontinuous portion having a different content form such as a format (S25). When the dividing unit 103 determines that there is a discontinuous part having a different form in a part of the acquired content B (Yes in S25), the dividing unit 103 divides the content B by a part having a discontinuous form (S26). The discontinuity information adding unit 104 adds information on the form of the continuous area P12 to the size information of the continuous area P12 from the first discontinuous part to the second discontinuous part of the content B (S27). The content transmission unit 105 transmits the size information of the continuous area P12 including the size of the continuous area P12 and the form of the continuous area P12 to the playback apparatus 200, and then transmits the data of the continuous area P12 to the playback apparatus 200 (S28). ).

  Next, the dividing unit 103 checks whether or not the transmission of the content B is completed (S29). If the dividing unit 103 determines that the transmission of the content B is not completed (No in S29), the operation of the server 100 is performed in step S24. Returning to step S24, step S24 to step S29 are repeated. On the other hand, when the dividing unit 103 determines that the transmission of the content B has been completed (Yes in S29), as described above, the content transmitting unit 105 reproduces the size “0” indicating that the transmission of the content B has ended. It transmits to the apparatus 200 (S30), and the operation of the server 100 ends.

  In step S25, when the dividing unit 103 determines that there is no discontinuous part having a different form of content such as resolution or format in a part of the content B from the content generating unit 120 (No in S25), Operation proceeds to S27.

  In the playback apparatus 200, the content receiving unit 202 receives the continuous area P11 from the server 100 (S31), and confirms that the size “0” indicating that the transmission of the content B has not been transmitted ( No in S32), the discontinuous information analysis unit 203 confirms the form of the continuous area P11 (S33), and notifies the form of the continuous area P11 to the decoding unit 204 (S34).

  The decoding unit 204 decodes the continuous region P11 based on the information on the form of the continuous region P11 from the discontinuous information analysis unit 203 by a method suitable for the form of the continuous region P11 (S35), and the output unit 205 The continuous area P11 thus output is output to an output device external to the playback device 200 (S36).

  Next, the operation of the playback device 200 returns to step S31, and the content reception unit 202 receives the continuous area P12 from the server 100 (S31), and transmits a size “0” indicating that the transmission of the content B has ended. It is confirmed that it has not been performed (No in S32), and the discontinuous information analysis unit 203 confirms the form of the continuous region P2 (S33). Since the continuous region P12 includes information in a form different from the form of the continuous region P11 (S33), the discontinuous information analysis unit 203 notifies the decoding unit 204 of the form of the continuous region P12 (S34). .

  The decoding unit 204 decodes the continuous region P12 based on the information of the form of the continuous region P12 from the discontinuous information analysis unit 203 by a method suitable for the form of the continuous region P12 (S35), and the output unit 205 The continuous area P11 thus output is output to an output device external to the playback device 200 (S36).

  Specifically, for example, when the resolution of the content transmitted in the continuous area P11 is 720 × 480 and the resolution of the content transmitted in the next continuous area P12 is 360 × 240, the discontinuity information analysis unit 203 When notified, the decoding unit 204 changes the setting for decoding at a reduced resolution in advance, and waits for the data in the continuous area P12 to be input. The same applies to the format, for example, from MPEG2 to H.264. H.264, this H.264 Since the H.264 format information is notified from the discontinuous information analysis unit 203, the decoding unit 204 has previously received the H.264 format information. It changes to the setting for H.264 decoding, and waits for the data of the continuous area P12 to be input.

  Thereafter, the operation of the playback device 200 returns to step S31 again, and the discontinuous information analysis is performed to determine whether or not the data received by the content receiving unit 202 from the server 100 is the size “0” indicating that the transmission of the content B has ended. The unit 203 determines (S32). If the data received by the content receiving unit 202 is not the size “0” indicating that the transmission of the content B is completed, the operations from step S31 to step S36 are repeated. On the other hand, when the data received by the content receiving unit 202 is a size “0” indicating that the transmission of the content B has ended, the operation of the playback device 200 ends.

  As described above, in the communication network system according to the second embodiment, the server 100 transmits information in a form such as the resolution and format of each continuous area to the playback apparatus 200, and the playback apparatus 200 receives each continuous area from the server 100. By using the information in the form, the continuous continuous area is reproduced without interruption.

  In addition, when the time stamp of a certain continuous area (for example, continuous area P1) and the next continuous area (for example, continuous area P2) is not continuous, and the form (resolution, format, etc.) of both is different, the server 100, The difference between the playback time (time stamp) at the rear end of the previous continuous area and the playback time (time stamp) at the front end of the subsequent continuous area is transmitted to the playback apparatus 200. At the same time, the server 100 transmits the subsequent continuous area form to the playback device 200. The playback apparatus 200 continuously plays back two continuous areas without being interrupted as described in the first embodiment, and the subsequent continuous areas at the time of switching the continuous areas as described in the second embodiment. The subsequent continuous area is reproduced by a method adapted to the form of

  As a result, even when the server 100 transmits a certain continuous area and a next continuous area that have different time stamps and different forms (resolution, format, etc.) to the playback device 200, each area is The effect of continuous reproduction without interruption is obtained.

  In addition, when the time stamps of a certain continuous area and the next continuous area are not continuous and the form and the like of the two are different, the discontinuous information transmitted from the server 100 to the playback device 200 is described as follows, for example: Is done.

2BF200; PTS_Offset = 60000; Resolution = 720 × 480
This means that the difference between the playback times of the two continuous areas is “60000 seconds”, and the resolution of the subsequent continuous area is “720 × 480”.

  Alternatively, the discontinuity information may be as follows.

2BF200; AudioFormat = MP3
This means that the difference between the playback times of the two continuous areas is “60000 seconds”, and the format of the subsequent continuous area is “MP3”.

  The functions of the communication network system and server of the present invention described using the above-described embodiments may be realized using a program for causing a computer to realize the functions of the communication network system and server of the present invention. Good. That is, the present invention includes a program for causing a computer to realize the functions of the communication network system and the server of the present invention. The program may be read from a recording medium and taken into a computer, or may be transmitted via a communication network and taken into a computer.

  100 server, 101 transmission request communication unit, 102 storage unit, 103 division unit, 104 discontinuous information addition unit, 105 content transmission unit, 200 playback device, 201 reception side request communication unit, 202 content reception unit, 203 discontinuous information Analysis unit, 204 decoding unit, 205 output unit, 300 communication network.

Claims (6)

It is reproduced with reference to the reproduction time of the first content and the reference position of the first content by the HTTP chunk method in which the length information of the content to be transmitted and the content are inserted and transmitted in the response body. And transmitting the second content having a form different from that of the first content, information on a difference in reproduction time between the rear end of the first content and the front end of the second content, and the second content A server that also transmits information in the form of two contents;
Receiving the first content, the second content, the reproduction time difference information, and the second content form information from the server, and the reproduction time difference information; A communication network system comprising: a playback device that continuously plays back the first content and the second content using information in the form of the second content. If the server includes invalid data that cannot be reproduced in the first content or the second content, the server also transmits invalid information that specifies the position of the invalid data,
The communication network system according to claim 1, wherein the playback device skips and plays back the invalid data using the invalid information from the server. The communication network system according to claim 1, wherein the form is image resolution. The communication network system according to claim 1, wherein the form is a format. The server uses the HTTP chunk method in which the length information of the content to be transmitted and the content are inserted and transmitted in the response body, based on the playback time of the first content and the reference position of the first content. And the second content having a form different from that of the first content is transmitted, and information on the difference in playback time between the rear end of the first content and the front end of the second content; And also sends information in the form of the second content,
A playback device receives the first content, the second content, the difference in playback time, and the information in the form of the second content from the server, and the playback time A content playback method for continuously playing back the first content and the second content using the difference information and the information on the form of the second content.   It is reproduced based on the first content and the reproduction time at the reference position of the first content by the HTTP chunk method in which the length information of the content to be transmitted and the content are inserted and transmitted in the response body. And transmitting the second content having a form different from that of the first content, information on the difference in reproduction time between the rear end of the first content and the front end of the second content, and the second content A server that also transmits information in the form of content.

Images