JP2012191384A - Program receiver, program reception method, and program reception program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the shortening of a time to be required for program selection and also appropriate stream reception processing concerning a configuration for receiving and processing a stream where program information is divided into multiple packets.SOLUTION: A program receiver 101 includes: a buffer 12 for temporarily accumulating packets which are received by a reception part 11 and outputting them in accumulation order; a packet discrimination part 14 for discriminating the packets received from the buffer 12, based on identifiers; and an accumulation packet search part 17 for searching the packets to be indicated by the designated identifiers in the buffer 12. The accumulation packet search part 17 searches program map packets which are received during a period from the reception of a channel selection indication to the reception of a first program-related packet. The packet discrimination part 14 discriminates a reproduction object packet, based on the identifiers which are included in the program map packets searched by the accumulation packet search part 17.

Description

  The present invention relates to a program receiving apparatus, a program receiving method, and a program receiving program, and in particular, a program receiving apparatus, a program receiving method, and a program receiving program for receiving and processing a stream in which program information is divided into a plurality of packets. About.

  Japanese Patent Laying-Open No. 2006-262483 (Patent Document 1) discloses a technique for reducing the channel switching time in digital broadcasting. That is, an apparatus for controlling switching of a broadcast channel in a digital multimedia broadcast receiver, which is buffered to acquire program information related to the switched broadcast channel after first buffering a transmission stream packet. A first demultiplexer that searches a PAT (Program Association Table), a PMT (Program Map Table), and an intra frame from the received data; and the second buffering of the transmission stream packet, and the first demultiplexing A second demultiplexing unit that performs audio or video demultiplexing by searching for audio or video transmission stream packets of the corresponding broadcast channel from the second buffered transmission stream packets based on the program information acquired by the unit With.

  The following technique is disclosed in Japanese Translation of PCT International Publication No. 2005-522953 (Patent Document 2). That is, the device performs a data cache operation in response to a channel change event, and reduces the channel change time by the operation. The apparatus includes a cache memory that operates to cache an incoming data stream in response to a channel change command. The processor is operative to search for program specific information contained in the incoming data stream. A decoder decodes the cache data stream in response to the processor searching for the program specific information.

JP 2006-26283 A JP 2005-522953 A

  However, since the technique described in Patent Document 2 searches for the latest sequence block after the channel change command, not only the sequence header received after the PMT but also the sequence received before the PMT. There is a possibility of using the header. In this case, a program different from the desired program is reproduced.

  Also, Patent Document 1 does not disclose a configuration for solving such a problem.

  The present invention has been made to solve the above-described problems, and its object is to reduce the time required for selecting a program in a configuration in which a stream in which program information is divided into a plurality of packets is received and processed. In addition, a program receiving apparatus, a program receiving method, and a program receiving program capable of appropriately performing stream reception processing are provided.

  In order to solve the above problems, a program receiving apparatus according to an aspect of the present invention is a program receiving apparatus for receiving and processing a stream obtained by dividing information of one or a plurality of programs into a plurality of packets, The plurality of packets are generated corresponding to the reproduction target packet, the program map packet including the identifier of the reproduction target packet of the corresponding program, and the program including one or more identifiers of the program map packet. A receiving unit for receiving the packet, including a related packet; a buffer for temporarily storing the packets received by the receiving unit; and outputting the packets in the order of storage; and the packet received from the buffer A packet discriminating unit for discriminating based on the identifier and the packet indicated by the designated identifier in the buffer; And the stored packet search unit searches for the program map packet received from when a channel selection instruction is received until the first program-related packet is received. The packet determination unit determines the reproduction target packet based on the identifier included in the program map packet searched by the stored packet search unit.

  With such a configuration, with respect to a program map packet received from when a channel selection instruction is received until a program-related packet is received, a packet received after the program map packet can be used for program reproduction. Thereby, the time required for channel selection can be shortened. Further, since the received packet is not used for program playback in the period from receiving the channel selection instruction to receiving the program map packet, it is possible to prevent an inappropriate program from being played back along with the channel selection. it can.

  Preferably, when the stored packet search unit cannot search for the program map packet, the packet determination unit may store the buffer later than the program-related packet first received after receiving the channel selection instruction. The reproduction target packet is discriminated based on the identifier included in the program map packet received from.

  Thereby, even when the program map packet does not exist after the channel selection instruction is received until the program related packet is received, it is possible to prevent an inappropriate program from being reproduced along with the channel selection.

  Preferably, the program receiving apparatus further excludes the program-related packet from the packets stored in the buffer, and receives the channel selection instruction until the first program map packet is received. A storage packet discarding unit for deleting the received packet.

  With such a configuration, with respect to a program map packet received from when a channel selection instruction is received until a program-related packet is received, the packet received before the program map packet and after receiving the channel selection instruction is It can be surely prevented from being erroneously used for program reproduction.

  Preferably, upon receiving the channel selection instruction, the packet determination unit determines the reproduction target packet until the packet received after the program map packet searched by the stored packet search unit is received from the buffer. To stop.

  With such a configuration, with respect to a program map packet received from when a channel selection instruction is received until a program-related packet is received, the packet received before the program map packet and after receiving the channel selection instruction is It can be surely prevented from being erroneously used for program reproduction.

  Preferably, the program receiving apparatus further includes a stored packet discard unit for receiving the channel selection instruction and deleting the packet stored in the buffer.

  With such a configuration, it is possible to reliably prevent the reproduction or the like from being performed using the packet stored in the buffer at the time of receiving the channel selection instruction among the packets corresponding to the program before selection.

  Preferably, the stored packet search unit has received the program map packet received in the past in the buffer after receiving the channel selection instruction and before receiving the first program-related packet. Search in order from the packet.

  Thus, the program map packet can be searched at an early stage by the configuration in which the search is performed in order from the packet received in the past.

  Preferably, each of the program-related packet and the program map packet is repeatedly transmitted at a predetermined cycle, and the buffer is transmitted between the transmission of a certain program-related packet and the transmission of the next program-related packet. The packet to be transmitted can be stored at least.

  With such a configuration, it is possible to reliably search for a program map packet between program-related packets in the buffer.

  Preferably, the packet determining unit acquires the program-related packet from the packets received from the buffer, and the program receiving device further analyzes the program-related packet acquired by the packet determining unit. An identification information acquisition unit for notifying the packet determination unit of the identifier indicated by the program-related packet, the packet determination unit being notified from the identification information acquisition unit from the received packets The program map packet is acquired based on an identifier, and the identification information acquisition unit analyzes the program map packet acquired by the packet determination unit, acquires the identifier indicated by the program map packet, and determines the packet determination. Is based on the identifier indicated by the program map packet acquired by the identification information acquisition unit. The packet to be reproduced is determined from the packets received from the buffer, and the identification information acquisition unit receives the first program-related packet after receiving the channel selection instruction. When the stored program map packet is searched by the stored packet search unit, the packet determination unit notifies the identifier of the reproduction target packet indicated by the searched program map packet to the packet determination unit. The reproduction target packet is determined based on the identifier notified from the identification information acquisition unit.

  With such a configuration, in a configuration in which normal stream reception processing using a packet identifier is performed, it is possible to realize prevention of inappropriate program reproduction accompanying channel selection with a simple configuration and processing.

  More preferably, when the stored packet search unit is unable to search for the program map packet, the identification information acquisition unit is later than the program-related packet received first after receiving the channel selection instruction. The packet identifier is notified of the identifier indicated by the received program map packet.

  With such a configuration, in a configuration in which normal stream reception processing using a packet identifier is performed, even if a program map packet does not exist after receiving a channel selection instruction until a program-related packet is received, the channel It is possible to prevent an inappropriate program from being reproduced along with the selection with a simple configuration and processing.

  More preferably, when receiving the channel selection instruction, the packet determination unit stops determining the reproduction target packet until the identifier is newly notified from the identification information acquisition unit.

  With such a configuration, in a configuration in which normal stream reception processing using a packet identifier is performed, a program map packet received during a period from when a channel selection instruction is received until a program-related packet is received A simple configuration and processing can reliably prevent a packet received before a map packet and after receiving a channel selection instruction from being erroneously used for program reproduction.

  In order to solve the above problems, a program receiving method according to an aspect of the present invention is a program receiving method for receiving and processing a stream obtained by dividing information of one or a plurality of programs into a plurality of packets. The packet of the reproduction target packet indicating the content of the program, the program map packet generated corresponding to the program and including the identifier of the reproduction target packet of the corresponding program, and one or a plurality of the program map packets Including a program-related packet including an identifier, receiving the packet, temporarily storing the received packet, outputting the packet in the order of accumulation, and storing the packet indicated by the specified identifier A step of searching among packets, and a step of determining the packets output in the order of accumulation based on the identifiers. In the step of searching for the packet, in the step of searching for the program map packet received from when a channel selection instruction is received until the first program-related packet is received, and determining the packet Determines the reproduction target packet based on the identifier included in the searched program map packet.

  With such a configuration, with respect to a program map packet received from when a channel selection instruction is received until a program-related packet is received, a packet received after the program map packet can be used for program reproduction. Thereby, the time required for channel selection can be shortened. Further, since the received packet is not used for program playback in the period from receiving the channel selection instruction to receiving the program map packet, it is possible to prevent an inappropriate program from being played back along with the channel selection. it can.

  In order to solve the above problems, a program receiving program according to an aspect of the present invention is a program receiving program for receiving and processing a stream obtained by dividing information of one or a plurality of programs into a plurality of packets. The packet of the reproduction target packet indicating the content of the program, the program map packet generated corresponding to the program and including the identifier of the reproduction target packet of the corresponding program, and one or a plurality of the program map packets A program-related packet including an identifier, and receiving the packet in a computer; temporarily storing the received packet; outputting the packet in the accumulation order; and storing the packet indicated by the specified identifier Searching among the above-mentioned packets, and the packets output in the order of accumulation as the identifier And the step of searching for the packet, in the step of searching for the packet, the program received between the time the channel selection instruction is received and the first packet related to the program is received. In the step of searching the map packet and determining the packet, the reproduction target packet is determined based on the identifier included in the searched program map packet.

  With such a configuration, with respect to a program map packet received from when a channel selection instruction is received until a program-related packet is received, a packet received after the program map packet can be used for program reproduction. Thereby, the time required for channel selection can be shortened. Further, since the received packet is not used for program playback in the period from receiving the channel selection instruction to receiving the program map packet, it is possible to prevent an inappropriate program from being played back along with the channel selection. it can.

  According to the present invention, in a configuration in which a stream in which program information is divided into a plurality of packets is received and processed, the time required for selecting a program can be shortened and stream reception processing can be performed appropriately.

It is a figure which shows the structure of the program receiver which concerns on embodiment of this invention. It is the flowchart which defined the operation | movement procedure at the time of the TS filter part in the program receiver which concerns on embodiment of this invention performing the discrimination | determination and distribution process of TS packet. It is a figure for demonstrating the problem which arises by channel switching. It is a figure which shows the content change of a stream. It is a figure for demonstrating the other problem which arises by channel switching. It is the flowchart which defined the operation | movement procedure at the time of the channel switching process in the program receiver which concerns on embodiment of this invention. It is the flowchart which defined the operation | movement procedure when the program receiver and server which concern on embodiment of this invention switch a channel. It is the flowchart which defined the operation | movement procedure at the time of each unit in the program receiver which concerns on embodiment of this invention performs processes, such as initialization, according to a channel switching command. It is the flowchart which defined the operation | movement procedure at the time of the stored packet search part in the program receiver which concerns on embodiment of this invention performs the search process of TS packet. It is a figure which shows an example of the channel switching timing in the program receiver which concerns on embodiment of this invention. It is a figure which shows an example of the TS packet accumulate | stored in the buffer of the program receiver which concerns on embodiment of this invention. It is a figure which shows an example of the channel switching timing in the program receiver which concerns on embodiment of this invention. It is a figure which shows an example of the TS packet accumulate | stored in the buffer of the program receiver which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  [Configuration and basic operation]

  FIG. 1 is a diagram showing a configuration of a program receiving apparatus according to an embodiment of the present invention.

  Referring to FIG. 1, a program receiving apparatus 101 includes a receiving unit 11, a buffer 12, a TS filter unit (packet discriminating unit) 13, a demultiplexing unit (packet discriminating unit) 14, a video decoder 15, and an audio. A decoder 16, an accumulated packet search unit 17, and a control unit (identification information acquisition unit and accumulated packet discard unit) 18 are provided.

  The program receiving apparatus 101 receives and processes a stream obtained by dividing information of one or a plurality of programs into a plurality of packets. For example, the program receiving apparatus 101 receives and processes a stream according to the MPEG2-TS (Moving Picture Experts Group 2 Transport Stream) standard.

  More specifically, the program receiving apparatus 101 is, for example, an STB (Set Top Box), receives a stream from the station side apparatus, decodes video and audio from the stream, and reproduces the program on the display apparatus 102. The station-side device is, for example, a device installed in a digital broadcasting broadcast station or a server corresponding to IPTV (Internet Protocol Television). Note that the program receiving apparatus 101 may be configured to include the display apparatus 102.

  The stream includes a plurality of TS packets, and each TS packet includes a PID (Packet Identification) that is an identifier. The stream includes a TS packet indicating PSI (Program Specific Information) in addition to a video TS packet indicating program video and an audio TS packet indicating program audio. This PSI includes a PAT (Program Association Table) and a PMT (Program Map Table). The PAT includes one or more programs included in the stream, that is, a channel ID that is an identifier of one or more programs that are currently being broadcast, and a PMT PID that includes information on each broadcast channel. The PMT includes PIDs of video TS packets and audio TS packets that include the contents of the corresponding program. PAT and PMT are repeatedly transmitted from the station side device at predetermined intervals.

  That is, the plurality of TS packets in the stream includes a video TS packet and an audio TS packet, which are playback target packets indicating video or audio of the program. The plurality of TS packets in the stream include a PMT packet that is generated corresponding to a program and includes a PID of a reproduction target packet of the corresponding program, and a PAT packet that includes a PID of one or more PMT packets. Hereinafter, the PMT packet and the PAT packet may be simply referred to as PMT and PAT, respectively.

  More specifically, the receiving unit 11 receives a TS packet transmitted from the station side device and outputs the TS packet to the buffer 12.

  The buffer 12 is, for example, a FIFO (First In First Out), accumulates TS packets received from the receiving unit 11, and if TS packets are accumulated beyond a certain number, TS packets exceeding the certain number are accumulated. Output in order of accumulation. For example, the buffer 12 can store at least each TS packet transmitted between the transmission of one PAT packet and the transmission of the next PAT packet.

  The TS filter unit 13 outputs the TS packet received from the buffer 12 to the demultiplexing unit 14. In addition, the TS filter unit 13 acquires a PAT packet from each TS packet received from the buffer 12. More specifically, the TS filter unit 13 refers to the PID of the TS packet and outputs a TS packet that matches the PID of the PAT registered in advance to the control unit 18.

  The demultiplexing unit 14 discriminates and outputs the reproduction target packet from the TS packets received from the buffer 12 via the TS filter unit 13. More specifically, the demultiplexing unit 14 refers to the PID of the TS packet received from the TS filter unit 13 to determine whether or not it matches the PID of the video TS packet notified from the control unit 18, The matched TS packet is output to the video decoder 15. Further, the demultiplexing unit 14 determines whether or not it matches the PID of the audio TS packet notified from the control unit 18, and outputs the matching TS packet to the audio decoder 16.

  In this way, with the configuration in which the buffer 12 is provided before the demultiplexing unit 14, after the PID is acquired from the PMT, the demultiplexing unit 14 receives the TS packet from the buffer 12, and performs the discrimination and distribution processing of the packet to be reproduced. Can be performed.

  The video decoder 15 performs a decoding process on the TS packet received from the demultiplexing unit 14 to generate a video signal, and outputs the video signal to the display device 102.

  The audio decoder 16 performs a decoding process on the TS packet received from the demultiplexing unit 14 to generate an audio signal, and outputs the audio signal to the display device 102.

  The display device 102 reproduces a program based on the video signal received from the video decoder 15 and the audio signal received from the audio decoder 16.

  FIG. 2 is a flowchart defining an operation procedure when the TS filter unit in the program receiving apparatus according to the embodiment of the present invention performs TS packet discrimination and distribution processing.

  Referring to FIG. 2, first, TS filter unit 13 monitors the PID of the TS packet received from buffer 12 (step S1).

  Next, the TS filter unit 13 acquires a TS packet that matches the PID of the PAT packet (step S2) and outputs the TS packet to the control unit 18 (step S3).

  Next, the control unit 18 analyzes the TS packet received from the TS filter unit 13, that is, the PAT packet, acquires the PID of the PMT packet (step S4), and notifies the TS filter unit 13 of the PID of the PMT packet (step S4). S5).

  Next, the TS filter unit 13 acquires a TS packet that matches the PID of the PMT packet notified from the control unit 18 (step S6), and outputs the TS packet to the control unit 18 (step S7). Thereafter, the TS filter unit 13 continuously monitors the PID of the TS packet received from the buffer 12 (step S11).

  Next, the control unit 18 analyzes the TS packet, that is, the PMT packet received from the TS filter unit 13, and acquires the PID of the video TS packet and the audio TS packet of the program corresponding to the PMT packet (step S8). The PID of the video TS packet and the PID of the audio TS packet are notified to the demultiplexing unit 14 (step S9).

  Next, the demultiplexing unit 14 performs TS packet discrimination and distribution processing based on the PID of the video TS packet and the audio TS packet newly notified from the control unit 18 (step S10).

  FIG. 3 is a diagram for explaining a problem caused by channel switching. In FIG. 3, the horizontal axis represents time, and the information transmitted in the past is shown on the left side of the page.

  Referring to FIG. 3, consider the case where the program receiving apparatus performs the following operation. That is, the program receiving apparatus receives the PAT after receiving the channel switching command, and acquires PMT1 corresponding to the PID included in the PAT. Then, the program receiving apparatus determines the video TS packet and the audio TS packet received by the program receiving apparatus 101 before PMT1 using the PID of the video TS packet and the audio TS packet included in PMT1, and Perform playback.

  Here, when the PMT2 transmitted from the station-side device before the program receiving apparatus receives the channel switching command and the PMT1 received by the program receiving apparatus after receiving the channel switching command, the contents are as follows. There is no problem even if the operation is performed, and the time required for channel switching can be shortened.

  FIG. 4 is a diagram showing the change of the contents of the stream.

  In the stream, the program is changed between the generation timing of PMT2 and the generation timing of PMT1, and the contents of PMT1 and PMT2 may be different. In the example shown in FIG. 4, before the program change, the PIDs of the 21ch, 22ch, and 23ch video TS packets are 100, 101, and 102, respectively, and the PIDs of the audio TS packets are 110, 111, and 112, respectively. After the program change, the PIDs of the video TS packets of 21ch, 22ch, and 23ch are all 100 and the PIDs of the audio TS packets are all 110.

  For example, it is assumed that PMT1 and PMT2 correspond to a 22ch program and 22ch is selected by channel switching. In this case, the demultiplexing unit 14 outputs the TS packet of PID “100” of the 22ch video TS packet included in the PMT1 and the TS packet of PID “110” of the audio TS packet to the video decoder 15 and the audio decoder 16, respectively. .

  Here, since the TS packet received by the program receiving apparatus 101 before receiving the PMT1 is the TS packet transmitted before the program change, the TS packet with the PID “100” and the TS packet with the PID “110” are , 21ch video TS packet and audio TS packet. For this reason, after receiving the channel switching command, an inappropriate program, that is, a 21ch program is reproduced at first.

  FIG. 5 is a diagram for explaining another problem caused by channel switching. The way of viewing the figure is the same as in FIG.

  Referring to FIG. 5, consider the case where age viewing restrictions are set for a program. In general, age viewing restriction is performed based on PMT information.

  For example, a period before PMT1 is a viewing prohibition period, and a period after PMT1 is a viewable period, that is, a TS packet that arrives at the program receiving apparatus 101 before PMT1 is received is subject to age viewing restriction. Assume that a TS packet that arrives at the program receiving apparatus 101 after receiving is not subject to age viewing restriction.

  In such a situation, the program receiving apparatus receives a channel switching command after the PMT2 is transmitted from the station side apparatus until the program receiving apparatus receives the PMT1, and then receives the PAT1 and receives the PAT1. PMT1 corresponding to the included PID is acquired. Then, the program receiving apparatus determines the video TS packet and the audio TS packet received by the program receiving apparatus 101 before PMT1 using the PID of the video TS packet and the PID of the audio TS packet included in PMT1, and Perform playback.

  In this case, TS packets received by the program receiving apparatus before receiving PMT1 are processed in the same manner as TS packets that are not subject to age viewing restriction after PMT1 is received, even though they are subject to age viewing restriction. Inappropriate programs that ignore age restrictions are played.

  Therefore, the program receiving apparatus according to the embodiment of the present invention solves the above problems by performing the following operations.

  The accumulated packet search unit 17 searches the buffer 12 for a PMT packet received from when a channel switching command indicating a channel to be selected is received until the first PAT packet is received. Here, the channel indicated by the channel switching command may be one of the multi-channels. For example, the accumulated packet search unit 17 searches the buffer 12 in order from TS packets received in the past in the buffer 12.

  Then, the demultiplexing unit 14 determines and outputs a reproduction target packet based on the PID included in the PMT packet searched by the stored packet searching unit 17.

  More specifically, the control unit 18 analyzes the PAT packet acquired by the TS filter unit 13 and notifies the TS filter unit 13 of the PID indicated by the PAT packet.

  Next, the TS filter unit 13 acquires a PMT packet based on the PID notified from the control unit 18 from among the TS packets received from the buffer 12.

  Next, the control unit 18 analyzes the PMT packet acquired by the TS filter unit 13 and acquires the PID indicated by the PMT packet.

  Next, based on the PID indicated by the PMT packet acquired by the control unit 18, the demultiplexing unit 14 discriminates and outputs the reproduction target packet from among the TS packets received from the TS filter unit 13.

  Next, when the PMT packet received from when the channel switching command is received until the first PAT packet is received is searched by the accumulated packet search unit 17, the control unit 18 searches for the searched PMT. The demultiplexing unit 14 is notified of the PID of the reproduction target packet indicated by the packet.

  Then, the demultiplexing unit 14 determines and outputs a reproduction target packet based on the PID notified from the control unit 18.

  In addition, when the accumulated packet search unit 17 cannot search for the PMT packet, the demultiplexing unit 14 receives the PMT packet received from the buffer 12 after the PAT packet received first after receiving the channel switching command. Based on the indicated PID, the reproduction target packet is determined and output. More specifically, when the accumulated packet retrieval unit 17 cannot retrieve the PMT packet, the control unit 18 determines that the PMT packet received after the PAT packet received first after receiving the channel switching command is received. The demultiplexing unit 14 is notified of the indicated PID.

  Further, the control unit 18 receives the channel switching command and deletes each TS packet stored in the buffer 12.

  Further, the control unit 18 excludes the PAT packet from among the TS packets stored in the buffer 12, and receives each TS packet received from when the channel switching command is received until the first PMT packet is received. delete.

  Further, when receiving the channel switching command, the demultiplexing unit 14 stops the discrimination and output of the reproduction target packet until receiving from the buffer 12 each TS packet received after the PMT packet searched by the stored packet searching unit 17. To do. More specifically, when receiving the channel switching command, the demultiplexing unit 14 stops determining and outputting the reproduction target packet until a new PID is notified from the control unit 18.

[Operation]
Next, the operation when the program receiving apparatus according to the embodiment of the present invention performs the channel switching process will be described in detail with reference to the drawings.

  The program receiving apparatus 101 reads out each step of each flowchart shown below from a memory (not shown) and executes it. This program can be installed externally. The installed program is distributed in a state stored in a recording medium, for example.

  FIG. 6 is a flowchart defining an operation procedure when the program receiving apparatus according to the embodiment of the present invention performs the channel switching process.

  Referring to FIG. 6, first, program receiving apparatus 101 continues the normal stream receiving process until a channel switching command is received (NO in step S61).

  Next, when receiving the channel switching command (YES in step S61), the program receiving apparatus 101 searches the TS packets stored in the buffer 12 for the first PAT packet received after receiving the channel switching command. (Step S62).

  Next, the program receiving apparatus 101 searches for the PMT packet received before the first PAT packet from among the TS packets stored in the buffer 12, and if the search is successful (YES in step S63). Then, the PID of the video TS packet and the PID of the audio TS packet are acquired from the retrieved PMT packet (step S64).

  Next, the program receiving apparatus 101 receives the video TS packet received after the searched PMT packet from among the TS packets stored in the buffer 12 based on the acquired PID of the video TS packet and the PID of the audio TS packet. Then, the audio TS packet is discriminated and distributed, the video and audio are decoded, and the program is reproduced on the display device 102 (step S65).

  On the other hand, when the PMT packet received before the first PAT packet does not exist in each TS packet stored in the buffer 12 (NO in step S63), the program receiving apparatus 101 The PID of the video TS packet and the PID of the audio TS packet are acquired from the PMT packet received after the PAT packet (step S66). That is, the program receiving apparatus 101 returns to the normal stream receiving process. More specifically, the accumulated packet search unit 17 ends the process, and the TS filter unit 13 acquires the PMT packet received after the first PAT packet by using the PID of the PMT packet notified from the control unit 18. And output to the control unit 18. Alternatively, the accumulated packet search unit 17 may continue the processing and search the buffer 12 for PMT packets received after the first PAT packet.

  Next, based on the acquired PID of the video TS packet and the PID of the audio TS packet, the program receiving apparatus 101 determines the video TS packet received after the PMT packet from among the TS packets stored in the buffer 12. PID and audio TS packet PID discrimination and distribution processing are performed, video and audio are decoded, and a program is reproduced on the display device 102 (step S67).

  FIG. 7 is a flowchart defining an operation procedure when the program receiving apparatus and the server according to the embodiment of the present invention perform channel switching. For example, the control unit 18 performs the processing on the program receiving apparatus 101 side.

  Referring to FIG. 7, in the IPTV system, for example, in a state where program receiving apparatus 101 is receiving a stream of the old channel from the server (step S41), for example, a channel switching command is received from the user (step S42). .

  Next, the program receiving apparatus 101 receives a channel switching command and transmits a channel change request to the server (step S43).

  Next, the server receives a channel change request from the program receiving apparatus 101, and transmits a stream of a new channel indicated by the channel change request to the program receiving apparatus 101 (step S44).

  FIG. 8 is a flowchart defining an operation procedure when each unit in the program receiving apparatus according to the embodiment of the present invention performs processing such as initialization in accordance with a channel switching command.

  Referring to FIG. 8, first, control unit 18 receives a channel switching command (step S51), and outputs a reception processing stop command to each unit (step S52).

  The control unit 18 deletes all TS packets in the buffer 12 (step S53). As a result, it is possible to prevent reproduction or the like from being performed using the TS packets stored in the buffer 12 when the channel switching command is received among the TS packets corresponding to the channel before switching.

  Next, the video decoder 15 and the audio decoder 16 receive the reception process stop command from the control unit 18 and stop the decoding process for the TS packet from the demultiplexing unit 14 (step S54).

  Further, the demultiplexing unit 14 receives the reception processing stop command from the control unit 18 and stops the TS packet discrimination and distribution processing received from the TS filter unit 13. For example, the demultiplexing unit 14 clears the currently used video TS packet PID and audio TS packet PID (step S55). Thereby, the reproduction of the program is stopped until the PID of the video TS packet and the PID of the audio TS packet are newly notified from the control unit 18.

  Next, the processing of each step shown in FIG. 7 is performed between the control unit 18 and the server. When the control unit 18 transmits a channel change request to the server (step S56), the reception processing restart command is output to each unit. (Step S57).

  Next, each unit resumes the TS packet reception process. Specifically, the PID of the video TS packet and the PTS of the audio TS packet are newly notified to the demultiplexing unit 14 by the processing of the accumulated packet search unit 17 and the control unit 18, and the demultiplexing unit 14 receives the TS filter unit 13. The TS packet determination and distribution process received from step 1 is resumed (step S58).

  FIG. 9 is a flowchart defining an operation procedure when the stored packet search unit in the program receiving apparatus according to the embodiment of the present invention performs a TS packet search process.

  Referring to FIG. 9, first, control unit 18 receives a channel switching command and deletes all TS packets in buffer 12 (step S21 and step S53 in FIG. 8), and then newly outputs from reception unit 11. The TS packets are accumulated in the buffer 12. Next, the accumulated packet search unit 17 receives a reception process restart command from the control unit 18 (step S22 and step S57 in FIG. 8), and refers to the PID of the TS packet in the buffer 12, thereby A TS packet that matches the PID is searched (step S23).

  Next, the accumulated packet search unit 17 acquires a TS packet that matches the PID of the PAT packet (step S24), and outputs it to the control unit 18 (step S25).

  Next, the control unit 18 analyzes the TS packet, that is, the PAT packet received from the stored packet search unit 17 to acquire the PID of the PMT packet (step S26), and notifies the stored packet search unit 17 of the PID of the PMT packet. (Step S27).

  Next, the accumulated packet search unit 17 acquires a TS packet that matches the PID of the PMT packet notified from the control unit 18 (step S28), and outputs the TS packet to the control unit 18 (step S29). Thereafter, the stored packet search unit 17 waits until the program receiving apparatus 101 receives the next channel switching command, that is, until it receives the receiving process restart command from the control unit 18 (step S34).

  Next, the control unit 18 deletes each TS packet in the buffer 12 stored before the PMT packet, regarding the TS packet received from the stored packet search unit 17, that is, the PMT packet. That is, the control unit 18 deletes each TS packet received between the time when the channel switching command is received and the time when the first PMT packet is received (step S30).

  Next, the control unit 18 analyzes the TS packet, that is, the PMT packet received from the accumulated packet search unit 17, and obtains the PID of the video TS packet and the audio TS packet of the program corresponding to the PMT packet (step S31). ), The PID of the video TS packet and the PID of the audio TS packet are notified to the demultiplexing unit 14 (step S32).

  Next, the demultiplexing unit 14 performs TS packet discrimination and distribution processing based on the PID of the video TS packet and the audio TS packet newly notified from the control unit 18 (step S33).

  The operation procedure shown in FIG. 9 is executed when the PMT is first acquired after receiving the channel switching command. Thereafter, the PMT can be acquired according to the operation procedure shown in FIG. 2 until the next channel is switched.

  FIG. 10 is a diagram showing an example of channel switching timing in the program receiving apparatus according to the embodiment of the present invention.

  Referring to FIG. 10, when PMTa received before PATa received first is present in buffer 12 after timing t1 when the channel switching command is received, program receiving apparatus 101 receives PMTa. The video TS packet and the audio TS packet received during the period from the reception to the PATa are used for program reproduction. That is, a TS packet received in a period Ta after PMTa can be used for program reproduction. Thereby, the time required for channel switching can be shortened.

  Since the program receiving apparatus 101 does not use the PID and audio TS packet of the video TS packet received during the period Tk from when the channel switching command is received until the PMTa is received, to the program playback, FIG. It is possible to prevent the problem as shown.

  FIG. 11 is a diagram showing an example of TS packets stored in the buffer of the program receiving apparatus according to the embodiment of the present invention. In FIG. 11, V is a video TS packet, A is an audio TS packet, PAT is a PAT packet, and PMT is a PMT packet. In addition, the horizontal axis represents time, and the left side of the drawing indicates TS packets received in the past.

  Referring to FIG. 11, program receiving apparatus 101 receives PMTa after receiving PMTa since PMTa before PATa received first is present in buffer 12 after timing t1 at which the channel switching command is received. Three TS packets indicated by P2 until reception and one packet indicated by P1 received after PATa are used for program reproduction.

  The program receiving apparatus 101 does not use the six packets indicated by P3 received before PMTa for program reproduction.

  FIG. 12 is a diagram showing an example of channel switching timing in the program receiving apparatus according to the embodiment of the present invention.

  Referring to FIG. 12, when the PMT before the first received PATb does not exist in the buffer 12 after the timing t <b> 1 when the channel switching command is received, the program receiving apparatus 101 determines the PMTb received after the PATb. , Video TS packets and audio TS packets received in a period Tb after PMTb are used for program reproduction.

  Since the program receiving apparatus 101 does not use the PID and audio TS packet of the video TS packet received during the period Tk from when the channel switching command is received until the PMTb is received, to the program reproduction, FIG. It is possible to prevent the problem as shown.

  FIG. 13 is a diagram showing an example of TS packets stored in the buffer of the program receiving apparatus according to the embodiment of the present invention. The view of FIG. 13 is the same as that of FIG.

  Referring to FIG. 13, since the PMT before the first received PATb does not exist in the buffer 12 after the timing t1 when receiving the channel switching command, the program receiving apparatus 101 is indicated by P11 received after the PMTb. Four TS packets are used for program reproduction.

  The program receiving apparatus 101 does not use the five packets indicated by P12 and P13 received before PMTb for program reproduction.

  By the way, in the technique described in Patent Document 2, since the latest sequence block after the channel change command is searched, not only the sequence header received after the PMT but also the sequence received before the PMT. There is a possibility of using the header. In this case, a program different from the desired program is reproduced.

  On the other hand, in the program receiving apparatus according to the embodiment of the present invention, receiving unit 11 receives a TS packet. The buffer 12 temporarily accumulates TS packets received by the receiving unit 11 and outputs them in the order of accumulation. The demultiplexer 14 determines and outputs the TS packet received from the buffer 12 based on the PID. The accumulated packet search unit 17 searches the buffer 12 for PMT packets received during the period from when the channel switching command is received until the first PAT packet is received. Then, the demultiplexing unit 14 determines and outputs a reproduction target packet based on the PID included in the PMT packet searched by the stored packet searching unit 17.

  With such a configuration, with respect to the PMT packet received from when the channel switching command is received until the PAT packet is received, the TS packet received after the PMT packet can be used for program reproduction. Thereby, the time required for channel switching can be shortened. In addition, since the video TS packet and audio TS packet received during the period from receiving the channel switching command to receiving the PMT packet are not used for program playback, an inappropriate program is played back when the channel is switched. Can be prevented.

  Further, in the program receiving apparatus according to the embodiment of the present invention, the demultiplexing unit 14 is first received after receiving the channel switching command when the accumulated packet searching unit 17 cannot search the PMT packet. Based on the PID included in the PMT packet received from the buffer 12 after the PAT packet, the reproduction target packet is determined and output.

  As a result, it is possible to prevent an inappropriate program from being reproduced along with channel switching even when there is no PMT packet between the reception of the channel switching command and the reception of the PAT packet.

  In the program receiving apparatus according to the embodiment of the present invention, the control unit 18 receives the first PMT packet after receiving the channel switching command, except for the PAT packet, among the TS packets stored in the buffer 12. Each TS packet received until it is deleted is deleted.

  With such a configuration, for a PMT packet received from when a channel switching command is received until a PAT packet is received, the video TS packet and audio received before the PMT packet and after receiving the channel switching command. It is possible to reliably prevent the TS packet from being erroneously used for program reproduction.

  In the program receiving apparatus according to the embodiment of the present invention, when receiving the channel switching command, the demultiplexing unit 14 buffers each TS packet received after the PMT packet searched by the stored packet searching unit 17. Until receiving from, the discrimination and output of the reproduction target packet are stopped.

  With such a configuration, for a PMT packet received from when a channel switching command is received until a PAT packet is received, the video TS packet and audio received before the PMT packet and after receiving the channel switching command. It is possible to reliably prevent the TS packet from being erroneously used for program reproduction.

  In the program receiving apparatus according to the embodiment of the present invention, the control unit 18 receives each channel switching command and deletes each TS packet stored in the buffer 12.

  With such a configuration, it is possible to reliably prevent reproduction or the like from being performed using the TS packets stored in the buffer 12 at the time of receiving the channel switching command among the TS packets corresponding to the channel before switching. it can.

  In the program receiving apparatus according to the embodiment of the present invention, the accumulated packet search unit 17 uses the buffer 12 to receive the PMT packet received during the period from when the channel switching command is received until the first PAT packet is received. , Search in order from the TS packets received in the past.

  As described above, the PMT packet can be searched early by the configuration in which the search is performed in order from the TS packets received in the past.

  Moreover, in the program receiving apparatus according to the embodiment of the present invention, the PAT packet and the PMT packet are repeatedly transmitted at a predetermined period. The buffer 12 can store at least each TS packet transmitted from the time when a certain PAT packet is transmitted until the next PAT packet is transmitted.

  With such a configuration, it is possible to reliably search for PMT packets between PAT packets in the buffer.

  In the program receiving apparatus according to the embodiment of the present invention, the TS filter unit 13 receives TS packets from the buffer 12 and outputs them to the demultiplexing unit 14, and obtains PAT packets from the received TS packets. To do. The control unit 18 analyzes the PAT packet acquired by the TS filter unit 13 and notifies the TS filter unit 13 of the PID indicated by the PAT packet. The TS filter unit 13 acquires a PMT packet based on the PID notified from the control unit 18 from the received TS packets. The control unit 18 analyzes the PMT packet acquired by the TS filter unit 13 and acquires the PID indicated by the PMT packet. Based on the PID indicated by the PMT packet acquired by the control unit 18, the demultiplexing unit 14 discriminates and outputs the reproduction target packet from among the TS packets received from the TS filter unit 13. When the PMT packet received from when the channel switching command is received until the first PAT packet is received is searched by the accumulated packet search unit 17, the control unit 18 indicates the searched PMT packet. The demultiplexing unit 14 is notified of the PID of the packet to be reproduced. Then, the demultiplexing unit 14 determines and outputs a reproduction target packet based on the PID notified from the control unit 18.

  With such a configuration, in a configuration in which a normal stream reception process using a packet identifier is performed, it is possible to prevent reproduction of an inappropriate program accompanying channel switching with a simple configuration and process.

  Further, in the program receiving apparatus according to the embodiment of the present invention, when the accumulated packet search unit 17 cannot search for the PMT packet, the control unit 18 first receives the PAT received after receiving the channel switching command. The demultiplexing unit 14 is notified of the PID indicated by the PMT packet received after the packet.

  With such a configuration, in a configuration in which normal stream reception processing using a packet identifier is performed, channel switching can be performed even when no PMT packet exists between receiving a channel switching command and receiving a PAT packet. Accordingly, it is possible to prevent an inappropriate program from being reproduced with a simple configuration and processing.

  Further, in the program receiving apparatus according to the embodiment of the present invention, when the demultiplexing unit 14 receives the channel switching command, the demultiplexing unit 14 stops determining and outputting the reproduction target packet until a new PID is notified from the control unit 18. To do.

  With such a configuration, in a configuration in which normal stream reception processing using a packet identifier is performed, a PMT packet received between receiving a channel switching command and receiving a PAT packet is received from the PMT packet. It is possible to reliably prevent a video TS packet and an audio TS packet received before and after receiving a channel switching command from being erroneously used for program reproduction with a simple configuration and processing.

  The program receiving apparatus according to the embodiment of the present invention is configured to execute the stream receiving process for appropriately performing the program reproduction accompanying the channel switching command, but the present invention is not limited to this. A channel selection instruction for selecting a channel is not limited to a channel switching instruction. For example, a similar stream reception process can be applied to a channel selection instruction when the program receiving apparatus 101 is activated. is there. Moreover, the channel selection instruction | indication performed by selecting a program from a program schedule may be sufficient.

  In the program receiving apparatus according to the embodiment of the present invention, the demultiplexing unit 14 is configured to distribute the video TS packet and the audio TS packet. However, the present invention is not limited to this. If only one of video and audio is to be reproduced, the demultiplexing unit 14 determines a video TS packet or an audio TS packet from each packet received from the TS filter unit 13 and outputs it. Good.

  In the program receiving apparatus according to the embodiment of the present invention, the video TS packet and the audio TS packet are the reproduction target packets, but the present invention is not limited to this. The program receiving apparatus 101 may be configured to reproduce subtitles, data broadcasts, and the like in addition to video and audio. The subtitles and the data broadcast may be unrelated to the content of the reproduction target program.

  Further, in the program receiving apparatus according to the embodiment of the present invention, the demultiplexing unit 14 determines the playback target packet from the TS packets received from the buffer 12 via the TS filter unit 13 and outputs the packet. Although there is, it is not limited to this. The demultiplexing unit 14 may be configured to discriminate the reproduction target packet, and may be configured to discard packets other than the reproduction target packet or may not be discarded.

  In the program receiving apparatus according to the embodiment of the present invention, the TS filter unit 13 and the demultiplexing unit 14 are separately provided. However, the TS filter unit 13 and the demultiplexing unit 14 have a common hardware configuration. It may be provided in common such as realized by a wear circuit.

  In addition, the program receiving apparatus according to the embodiment of the present invention is configured to perform stream receiving processing according to the MPEG2-TS standard, but the present invention is not limited to this. It may be configured to perform stream reception processing according to another standard.

  The above embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

11 Receiver 12 Buffer 13 TS Filter (Packet Discrimination Unit)
14 Inverse multiplexing part (packet discrimination part)
15 Video decoder 16 Audio decoder 17 Stored packet search unit 18 Control unit (identification information acquisition unit and stored packet discard unit)
101 Program receiving device

Claims (12)

A program receiving apparatus for receiving and processing a stream obtained by dividing information of one or more programs into a plurality of packets,
The plurality of packets are a reproduction target packet, a program map packet generated corresponding to the program and including an identifier of the reproduction target packet of the corresponding program, and a program including an identifier of one or more program map packets Including related packets,
A receiving unit for receiving the packet;
A buffer for temporarily storing the packets received by the receiving unit and outputting them in the order of storage;
A packet determining unit for determining the packet received from the buffer based on the identifier;
An accumulated packet search unit for searching in the buffer for the packet indicated by the specified identifier,
The stored packet search unit searches for the program map packet received between receiving a channel selection instruction and receiving the first program-related packet,
The program receiving device, wherein the packet discriminating unit discriminates the reproduction target packet based on the identifier included in the program map packet searched by the stored packet searching unit.   The packet discriminating unit received from the buffer later than the program-related packet received first after receiving the channel selection instruction when the accumulated packet searching unit could not search the program map packet. The program receiving apparatus according to claim 1, wherein the reproduction target packet is determined based on the identifier included in the program map packet. The program receiving device further includes:
The packet stored in the buffer, except for the program-related packet, is for deleting the packet received from when the channel selection instruction is received until the first program map packet is received. The program receiving apparatus according to claim 1, further comprising a stored packet discard unit.   When receiving the channel selection instruction, the packet determination unit stops determining the reproduction target packet until the packet received after the program map packet searched by the stored packet search unit is received from the buffer. The program receiving device according to any one of claims 1 to 3. The program receiving device further includes:
5. The program receiving device according to claim 1, further comprising: a stored packet discard unit that receives the channel selection instruction and deletes the packet stored in the buffer. 6.   The stored packet search unit receives the program map packet received from when the channel selection instruction is received until the first program-related packet is received from the packet received in the past in the buffer. The program receiving device according to any one of claims 1 to 5, wherein the program is searched in order. The program-related packet and the program map packet are each repeatedly transmitted at a predetermined cycle,
7. The buffer according to claim 1, wherein the buffer is capable of storing at least the packet transmitted between the time when the program-related packet is transmitted and the time when the next program-related packet is transmitted. The program receiving apparatus according to item 1. The packet discrimination unit acquires the program-related packet from the packets received from the buffer,
The program receiving device further includes:
An identification information acquisition unit for analyzing the program related packet acquired by the packet determination unit and notifying the packet determination unit of the identifier indicated by the program related packet;
The packet determination unit acquires the program map packet based on the identifier notified from the identification information acquisition unit from the received packet,
The identification information acquisition unit analyzes the program map packet acquired by the packet determination unit, acquires the identifier indicated by the program map packet,
The packet determination unit determines the reproduction target packet from the packets received from the buffer based on the identifier indicated by the program map packet acquired by the identification information acquisition unit,
The identification information acquisition unit, when the program map packet received from when the channel selection instruction is received until the first program-related packet is received is searched by the accumulated packet search unit, Notifying the packet discriminator of the identifier of the packet to be reproduced indicated by the searched program map packet;
The program receiving device according to claim 1, wherein the packet determining unit determines the reproduction target packet based on the identifier notified from the identification information acquiring unit.   The identification information acquisition unit, when the storage packet search unit cannot search the program map packet, received after the program-related packet received first after receiving the channel selection instruction The program receiving apparatus according to claim 8, wherein the identifier indicated by the program map packet is notified to the packet determination unit.   The said packet discrimination | determination part stops the discrimination | determination of the said reproduction | regeneration object packet, until the said identifier is newly notified from the said identification information acquisition part, if the said channel selection instruction | indication is received. Program receiving device. A program receiving method for receiving and processing a stream obtained by dividing information of one or a plurality of programs into a plurality of packets,
The plurality of packets are a reproduction target packet indicating the content of the program, a program map packet generated corresponding to the program and including an identifier of the reproduction target packet of the corresponding program, and one or a plurality of the program maps Including a program-related packet including the identifier of the packet;
Receiving the packet;
Temporarily storing the received packets and outputting them in the order of storage;
Retrieving the packet indicated by the specified identifier from the packets being stored;
Determining the packets output in the order of accumulation based on the identifiers;
In the step of searching for the packet, the program map packet received from when a channel selection instruction is received until the first program-related packet is received is searched,
The program receiving method, wherein in the step of discriminating the packet, the reproduction target packet is discriminated based on the identifier included in the searched program map packet. A program receiving program for receiving and processing a stream obtained by dividing information of one or more programs into a plurality of packets,
The plurality of packets are a reproduction target packet indicating the content of the program, a program map packet generated corresponding to the program and including an identifier of the reproduction target packet of the corresponding program, and one or a plurality of the program maps Including a program-related packet including the identifier of the packet;
On the computer,
Receiving the packet;
Temporarily storing the received packets and outputting them in the order of storage;
Retrieving the packet indicated by the specified identifier from the packets being stored;
And a step for determining the packets output in the order of accumulation based on the identifiers,
In the step of searching for the packet, the program map packet received from when a channel selection instruction is received until the first program-related packet is received is searched,
In the step of determining the packet, a program receiving program for determining the reproduction target packet based on the identifier included in the searched program map packet.

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