JP2006086993A - Data receiving apparatus, data receiving method, and data receiving program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data receiving apparatus, a data receiving method, and a data receiving program for adequately selecting TS packets to be abolished and effectively using a memory for temporarily storing the received TS packets. <P>SOLUTION: The data receiving apparatus comprises a receiving unit for extracting packets from the transmitting data, a cache control unit 34 for storing the packets normally received to a RAM 36 when at least one of the packets of the group to which the normally received packets belong is not received normally, and a deletion packet selecting unit 35. The cache control unit 34 controls, when vacant capacity of RAM36 is short, the deleting packet selecting unit 35 to select one or a plurality of packets in accordance with the predetermined conditions from the packets stored in the RAM36 and the normally received packets in order to delete the selected packets. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a data receiving apparatus, a data receiving method, and a data receiving program, and more particularly to a data receiving technique for reconfiguring data transmitted by being divided into a plurality of packets.

  The contents of the data broadcasting service for digital terrestrial broadcasting are composed of BML (Broadcast Markup Language) documents, image data, and the like, and are transmitted by one or a plurality of modules. As a system for transmitting this module, a DSM-CC (Digital Storage Media Command and Control) data carousel transmission system is adopted.

  FIG. 11 shows a data structure used in the DSM-CC data carousel transmission system. Modules are divided into data of a common size called a block. A block header is added to each of the divided blocks. The divided data to which the block header is added is further added with a section header and error detection data CRC (Cyclic Redundancy Check) to constitute a unit called a DSM-CC section. The DSM-CC section is divided into data of a common size in order to be multiplexed into a transport stream defined by the MPEG (Moving Picture Coding Experts Group) 2 Systems (ISO / IEC 13818-1) standard. This divided data becomes a payload of the TS (transport stream) packet.

  The TS packet has a fixed length of 188 bytes, and includes a 4-byte packet header, an adaptation field for transmitting additional information related to the stream, and a payload. In addition, only one of the adaptation field and the payload may be a constituent element of the TS packet.

  Various information such as video, audio and data is transmitted by the transport stream in which the TS packets are multiplexed.

  In the DSM-CC data carousel transmission method, modules divided in units of TS packets are arranged in a virtual rotating body called a carousel, and are repeatedly transmitted based on the rotation of the carousel. For this reason, even if the data broadcasting service starts to be viewed from the middle, it is possible to acquire all of the content by combining a part of the content received this time and a part of the content transmitted next time, You can watch the broadcast service from the beginning to the end.

  In the DSM-CC data carousel transmission system, a plurality of modules are periodically transmitted to form one carousel. The period of repeated transmission for each module (hereinafter referred to as a retransmission period) is usually different. In addition, data broadcasting service content may include a plurality of carousels. A carousel is also called a component from the aspect of a component of a broadcast program.

  FIG. 12 shows a conceptual diagram of data transmission performed in the DSM-CC data carousel transmission system. In carousel 1, module 0 and module 1 are transmitted.

  Here, the Z-th DSM-CC section belonging to the module Y transmitted in the carousel X is defined as a DSM-CC section X · YZ.

  The module 0 includes a DSM-CC section 1 • 00, a DSM-CC section 1 • 01, and a DSM-CC section 1 • 02.

  The module 1 includes DSM-CC sections 1 and 10, DSM-CC sections 1 and 11, DSM-CC sections 1 and 12, and DSM-CC sections 1 and 13.

  Further, the retransmission period of module 0 is shorter than that of module 1.

  Next, in the carousel 2, only the module 0 is transmitted.

  Module 0 is composed of a DSM-CC section 2.00 and a DSM-CC section 2.01.

  FIG. 13 shows the detailed structure of a TS packet defined by the MPEG2 Systems (ISO / IEC 13818-1) standard.

  The TS packet starts with a synchronization byte (8 bits) indicating the beginning of the packet, a transport error indicator (1 bit) indicating the presence or absence of an error in the packet, and a payload unit indicating that it starts from the payload of a new transport packet. An indicator (1 bit), a transport priority (1 bit) indicating the importance of this packet, a packet identifier (13 bits) for identifying this packet, and a transport scramble control indicating whether or not the payload is scrambled (2 bits), adaptation field control (2 bits) indicating the presence / absence of an adaptation field and the presence / absence of a payload, and a continuity index for detecting whether or not a packet has been partially discarded by the continuity of the reception count ( 4 bits) It consists of a packet header and the above-mentioned adaptation field and / or payload.

  Here, different packet identifiers are assigned to video, audio and data. In the DSM-CC data carousel transmission method, different packet identifiers are assigned to each carousel. Therefore, the receiving apparatus can separate video data and audio data based on this packet identifier, and can further separate carousels.

  In addition, in terrestrial digital broadcasting services for mobile terminals, mobile reception is performed, so the reception environment is unstable, and received TS packets often contain errors.

  Generally, in a receiving apparatus that receives content transmitted by the DSM-CC data carousel transmission method, it is possible to generate content by combining with other components or modules in units of components or modules. . However, when an error is detected for a TS packet in the process of generating a DSM-CC section or the like which is a smaller unit, the operation of generating a DSM-CC section or the like from a plurality of received TS packets is stopped, and the DSM -Discard the stored TS packets to generate CC sections and the like. Then, the receiving apparatus restarts generation of the DSM-CC section and the like from the beginning by using TS packets belonging to the same DSM-CC section and the like that are subsequently retransmitted.

On the other hand, in the data transmission device, the data reception device, the data transmission method, the data reception method, and the data transmission and data reception program described in Patent Document 1, the module number to which the TS packet belongs, the TS packet number, and the TS packet Arrangement information indicating the final TS packet number of the module to which the module belongs is inserted into the transport private data area in the option field (FIG. 13C) in the adaptation field (FIG. 13B). Then, the TS packet that does not include the error is temporarily stored, the TS packet corresponding to the TS packet that includes the error is received again, and all the TS packets corresponding to the module are received. Reconfiguration of With such a configuration, it is possible to shorten the acquisition time of received data and to efficiently use the transmission path or the recording medium.
JP 2004-23379 A

  By the way, in the data transmission device, the data reception device, the data transmission method, the data reception method, and the data transmission and data reception program described in Patent Document 1, in order to temporarily store TS packets that have been normally received, that is, do not include errors. Memory is required.

  Here, it is conceivable that a large number of TS packets are stored, so that there is a shortage of available memory and a new TS packet cannot be stored. That is, when a TS packet to be further stored is received in a state where the memory has insufficient free space, either the received TS packet or a TS packet stored in the memory must be discarded.

  However, in the data transmission device, the data reception device, the data transmission method, the data reception method, and the data transmission and data reception program described in Patent Document 1, the TS packet to be discarded is appropriately selected and the received TS packet is temporarily stored. For this reason, there is a drawback in that a configuration for efficiently using the memory is not provided.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a data receiving apparatus, a data receiving method, and a data receiving program that appropriately select a TS packet to be discarded and efficiently use a memory for temporarily storing the received TS packet. And

  In order to solve the above-described problem, a data receiving apparatus according to the present invention divides content into a plurality of packets, receives the transmission data repeatedly transmitted including the divided packets, A receiver that extracts and outputs a plurality of packets, a first memory for temporary storage, and receives a packet, determines whether or not the packet has been normally received, and is normal when the packet is normally received. When at least one of the packets of the group to which the received packet belongs is not normally received, a cache control unit that saves the normally received packet in the first memory, and a deletion packet selection that selects a packet to be deleted And the cache control unit has a free space in the first memory when the normally received packet is stored in the first memory. Is deleted, the deletion target selection command is output, and the deletion packet selection unit receives the deletion target selection command and receives one or a plurality of packets stored in the first memory and the normally received packet. From the reception completion packet, one or more packets are selected according to a predetermined condition, and deletion target packet information indicating a packet to be deleted is output to the cache control unit. The packet is deleted based on the target packet information.

  Preferably, the content is divided into one or a plurality of modules, the module is divided into one or a plurality of sections, the section is divided into one or a plurality of packets, and the transmission data is one or a plurality of packets. The packet includes packet specifying information for specifying the packet, the group is a section, and when the packet is normally received, the cache control unit indicates the section to which the normally received packet belongs. When at least one of the packets is not normally received, the normally received packet is stored in the first memory, and the cache control unit stores the first packet when the normally received packet is stored in the first memory. If there is not enough free space in the memory, specify the packet included in the reception complete packet. Outputs distribution for deletion selection command, delete the packet selection unit, on the basis of the packet identification information, selects one or a plurality of packets according to a predetermined condition from the received completion packet.

  More preferably, the packet specifying information is the number of packets included in the module to which each reception completion packet belongs, and the cache control unit outputs the packet specifying information when the first memory has insufficient free space. Then, the deleted packet selection unit selects a packet belonging to the module having the maximum or minimum number of packets based on the packet specifying information.

  More preferably, the packet identification information is the number of the module to which the reception completion packet belongs and the number of packets included in the module to which the reception completion packet belongs, and the cache control unit has insufficient free space in the first memory. In this case, the packet specifying information is output, and the deletion packet selecting unit determines the module based on the number of packets included in the module and the number of packets corresponding to the module among the reception completion packets based on the packet specifying information. And the packet belonging to the module having the smallest packet filling rate is selected.

  More preferably, the packet specifying information is a section number to which the reception completion packet belongs and a reception completion packet number in the section, and the cache control unit performs packet processing when the first memory has insufficient free space. Specific information is output, and the deletion packet selection unit selects a packet belonging to a section in which the first packet is not normally received from the sections to which the reception completion packet belongs, based on the packet identification information.

  More preferably, the packet specification information is a retransmission cycle of a module to which each reception completion packet belongs, and the cache control unit outputs and deletes the packet specification information when the first memory has insufficient free space. The packet selection unit selects a packet belonging to the module having the maximum or minimum retransmission cycle based on the packet identification information.

  More preferably, the packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the module to which the reception completion packet belongs, respectively. The cache control unit outputs packet specifying information when the first memory has insufficient free space, and the deleted packet selecting unit receives the packet based on the packet specifying information. The number of packets included in the module is calculated from the number of packets included in one or more sections belonging to a module and the number of sections included in the module among the sections to which the completion packet belongs. The number of Selecting a packet belonging to a module is.

  More preferably, the packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the module to which the reception completion packet belongs, respectively. The cache control unit outputs packet specifying information when the first memory has insufficient free space, and the deleted packet selecting unit receives the packet based on the packet specifying information. The number of packets included in the module is calculated from the number of packets included in one or more sections belonging to a module and the number of sections included in the module among the sections to which the completion packet belongs. The number of Tsu calculates a packet sufficiency rate from the number modules corresponding packet to the module of the bets, the packet fill rate selects packets belonging to a module is the minimum.

  More preferably, the packet specification information is a data amount of a module to which each reception completion packet belongs, and the cache control unit outputs the packet specification information and deletes when the first memory has insufficient free space. The packet selection unit selects a packet belonging to the module having the maximum or minimum data amount based on the packet specifying information.

  Preferably, the content is divided into one or a plurality of modules, the module is divided into one or a plurality of sections, the section is divided into one or a plurality of packets, and the transmission data is one or a plurality of packets. The packet includes packet specifying information for specifying the packet, the group is a section, and when the packet is normally received, the cache control unit indicates the section to which the normally received packet belongs. When all the packets are normally received, the section is generated and output, and all the packets corresponding to the section are deleted from the packets stored in the first memory, and the second memory for temporary storage When a section is received from the cache control unit, the sections that make up the module When at least one section is not received, the packet included in the section received from the cache control unit is stored in the second memory, and when all the sections constituting the module are received, the module is A data reconstruction unit that deletes all the packets corresponding to the module among the packets that are generated, output, and stored in the second memory, a browser that requests a module that includes the specified browsing data, and a browser A browser that generates and outputs a priority reception module specification indicating a module that should be received preferentially based on the module requested from the module, and outputs the module requested by the browser among the modules received from the data reconstruction unit The browser further includes a request processing unit, and the browser receives a module from the browser request processing unit. The received browsing data is extracted from the module and laid out, and the laid out browsing data is output. When the packet is normally received, the cache control unit receives the section of the section to which the normally received packet belongs. When at least one of the packets is not normally received, the normally received packet is stored in the first memory, and the cache control unit stores the first packet when the normally received packet is stored in the first memory. When the memory capacity of the packet is insufficient, the packet specifying information included in the reception completion packet is output as a deletion target selection command, and the deletion packet selecting unit is based on the packet specifying information and the priority receiving module designation. Select one or more packets from the received packets according to the specified conditions. Select.

  More preferably, the packet specifying information is a module number to which each reception completion packet belongs, and the cache control unit outputs the packet specifying information when the first memory has insufficient free space, and performs browser request processing. The unit outputs a priority reception module specification indicating a module including a startup document that is browsing data to be presented immediately after the browser is started, and the deletion packet selection unit receives the priority reception based on the packet identification information and the priority reception module specification. A packet belonging to a module other than the module indicated by the module designation is preferentially selected for deletion.

  More preferably, the packet specifying information is a module number to which each reception completion packet belongs, and the cache control unit outputs the packet specifying information when the first memory has insufficient free space, and performs browser request processing. The unit outputs a priority reception module specification indicating a module including the specified browsing data, and the deletion packet selection unit selects a module other than the module indicated by the priority reception module specification based on the packet identification information and the priority reception module specification. The packet to which it belongs is preferentially selected for deletion.

  More preferably, the content is divided into one or a plurality of components, the component is divided into one or a plurality of modules, and the packet belongs based on the packet identifier included in the header of the packet received from the receiving unit. It further includes a carousel identification unit that obtains the component number and outputs it to the cache control unit. When the cache control unit stores normally received packets in the first memory, the first memory has insufficient free space. In this case, the number of the component to which the reception completion packet belongs is further output to the deletion packet selection unit, the packet identification information is the number of the module to which the reception completion packet belongs, and the browser request processing unit Included in the component to which the module containing the data belongs The priority reception module designation indicating the module is output, and the deletion packet selection unit, based on the packet identification information, the component number and the priority reception module designation, includes the packet included in the module other than the component indicated by the priority reception module designation. Is preferentially selected for deletion.

  More preferably, the packet identification information further includes the number of the section to which the reception completion packet belongs and the number of packets included in the section to which the reception completion packet belongs, and the cache control unit has insufficient free space in the first memory If so, the packet specifying information is output, and the deletion packet selecting unit corresponds to the number of packets included in the section belonging to the selected module and the section of the reception completion packet based on the packet specifying information. The packet filling rate of the section is calculated from the number of packets, and a packet belonging to the section having the smallest packet filling rate is selected.

  More preferably, the cache control unit outputs packet specifying information when the free space of the first memory is insufficient, and the deletion packet selecting unit is a section belonging to the selected module based on the packet specifying information. The packet filling rate of the section is calculated from the number of packets included in the packet and the number of packets corresponding to the section of the reception completion packets, and the packet belonging to the section with the smallest packet filling rate is selected.

  The present invention is also a data receiving method in a data receiving apparatus having a first memory, wherein the content is divided into a plurality of packets, the transmission data including the divided packets and repeatedly transmitted is received. A receiving step for extracting and outputting one or more packets from the transmission data, receiving the packet, determining whether or not the packet has been normally received, and successfully receiving the packet when the packet has been normally received; When at least one of the packets of the group to which the packet belongs is not normally received, a cache control step for storing the normally received packet in the first memory, and a deletion packet selection step for selecting a packet to be deleted The cache control step includes storing the normally received packet in the first memory, When the memory capacity of one memory is insufficient, a deletion target selection command is output, and the deletion packet selection step receives the deletion target selection command and receives one or a plurality of data stored in the first memory. One or a plurality of packets are selected from a packet and a reception completion packet that is a normally received packet in accordance with a predetermined condition, and deletion target packet information indicating a deletion target packet is output. The packet is deleted based on the deletion target packet information.

  Preferably, the content is divided into one or a plurality of modules, the module is divided into one or a plurality of sections, the section is divided into one or a plurality of packets, and the transmission data is one or a plurality of packets. The packet includes packet specifying information for specifying the packet, the group is a section, and when the packet is normally received, the cache control step indicates the section to which the normally received packet belongs. When at least one of the packets is not normally received, the normally received packet is stored in the first memory, and the cache control step is configured to store the first received packet in the first memory. If there is not enough free memory in the Outputs packet specific information for deletion selection command, delete the packet selecting step, based on the packet identification information, selects one or a plurality of packets according to a predetermined condition from the received completion packet.

  More preferably, the packet identification information is the number of packets included in the module to which each reception completion packet belongs, and the cache control step outputs the packet identification information when the first memory has insufficient free space. The deletion packet selection step selects a packet belonging to the module having the maximum or minimum number of packets based on the packet specifying information.

  More preferably, the packet specifying information is the number of the module to which the reception completion packet belongs and the number of packets included in the module to which the reception completion packet belongs, and the cache control step has insufficient free space in the first memory The packet specifying information is output, and the deletion packet selecting step is performed based on the packet specifying information based on the number of packets included in the module and the number of packets corresponding to the module among the reception completion packets. And the packet belonging to the module having the smallest packet filling rate is selected.

  More preferably, the packet specifying information includes a section number to which the reception completion packet belongs and a reception completion packet number in the section, and the cache control step performs packet processing when the first memory has insufficient free space. The specific information is output, and the deletion packet selection step selects, based on the packet specific information, a packet belonging to a section in which the first packet is not normally received among the sections to which the reception completion packets belong.

  More preferably, the packet specification information is a retransmission cycle of a module to which each reception completion packet belongs, and the cache control step outputs and deletes the packet specification information when the first memory has insufficient free space. The packet selection step selects a packet belonging to the module having the maximum or minimum retransmission cycle based on the packet identification information.

  More preferably, the packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the module to which the reception completion packet belongs, respectively. The cache control step outputs packet specifying information when the first memory has insufficient free space, and the deleted packet selecting step receives the packet based on the packet specifying information. The number of packets included in the module is calculated from the number of packets included in one or more sections belonging to a module and the number of sections included in the module among the sections to which the completion packet belongs. Number of Selecting a packet belonging to a module is greater or minimum.

  More preferably, the packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the module to which the reception completion packet belongs, respectively. The cache control step outputs packet specifying information when the first memory has insufficient free space, and the deleted packet selecting step receives the packet based on the packet specifying information. The number of packets included in the module is calculated from the number of packets included in one or more sections belonging to a module and the number of sections included in the module among the sections to which the completion packet belongs. And the number of Calculating a packet sufficiency rate from the number modules corresponding packet to the module of the received completion packet, the packet fill rate selects packets belonging to a module is the minimum.

  More preferably, the packet specification information is a data amount of a module to which each reception completion packet belongs, and the cache control step outputs the packet specification information and deletes when the first memory has insufficient free space. The packet selection step selects a packet belonging to the module having the maximum or minimum data amount based on the packet specifying information.

  Preferably, the data receiving device further includes a second memory, the content is divided into one or a plurality of modules, the module is divided into one or a plurality of sections, and the section is composed of one or a plurality of sections. The transmission data is composed of one or a plurality of packets, the packet includes packet specifying information for specifying the packet, the group is a section, and the cache control step normalizes the packet. When all the packets of the section to which the normally received packet belongs are received normally when received, all the packets corresponding to the section among the packets stored in the first memory are generated and output. The data reception method is output in the cache control step. If at least one of the sections constituting the module is not received, the packet included in the section output in the cache control step is stored in the second memory, and the module is stored. When all the sections to be configured are received, a module is generated and output, and a data reconstruction step is performed to delete all packets corresponding to the module from among the packets stored in the second memory. A browser step for requesting a module including browsing data, and a priority reception module designation indicating a module to be received preferentially based on the module requested in the browser step is generated and output, and is output in the data reconstruction step. Out of modules A browser request processing step for outputting a module requested in the browser control step, wherein the browser step receives the module output in the browser request processing step, extracts specified browsing data from the module, and generates a layout. If the packet is normally received and the packet is normally received, if at least one of the packets of the section to which the normally received packet belongs is not normally received, the cache control step has received the packet normally. The packet is stored in the first memory, and the cache control step is included in the reception completion packet when the normally received packet is stored in the first memory and the free space of the first memory is insufficient. The packet specific information The deletion packet selection step selects one or a plurality of packets according to a predetermined condition from the reception completion packets based on the packet specification information and the priority reception module designation.

  More preferably, the packet specifying information is a module number to which the reception completion packet belongs, and the cache control step outputs the packet specifying information when the first memory has insufficient free space, and performs browser request processing. The step outputs a priority reception module designation indicating a module including a startup document which is browsing data to be presented immediately after the start of the browser control step, and the deletion packet selection step is based on the packet identification information and the priority reception module designation. Packets belonging to modules other than the module indicated by the priority receiving module designation are preferentially selected for deletion.

  More preferably, the packet specifying information is a module number to which the reception completion packet belongs, and the cache control step outputs the packet specifying information when the first memory has insufficient free space, and performs browser request processing. The step outputs the priority reception module designation indicating the module including the designated browsing data, and the deletion packet selection step is performed on a module other than the module indicated by the priority reception module designation based on the packet identification information and the priority reception module designation. The packet to which it belongs is preferentially selected for deletion.

  More preferably, the content is divided into one or a plurality of components, the components are divided into one or a plurality of modules, and the data reception method includes a packet identifier included in the header of the packet output in the reception step. Based on the above, it further includes a carousel identification step for obtaining and outputting the number of the component to which the packet belongs, and the cache control step is configured such that when the normally received packet is stored in the first memory, the free capacity of the first memory is If it is insufficient, the number of the component to which the reception completion packet belongs is further output, the packet specifying information is the number of the module to which the reception completion packet belongs, and the browser request processing step includes the specified browsing data The component to which the module belongs The priority reception module specification indicating the module included in the packet is output, and the deletion packet selection step is performed on the module belonging to the component other than the component indicated by the priority reception module specification based on the packet identification information, the component number, and the priority reception module specification. The included packets are preferentially selected for deletion.

  More preferably, the packet specifying information further includes a section number to which the reception completion packet belongs and a number of packets included in the section to which the reception completion packet belongs, and the cache control step is insufficient in the first memory free space If so, the packet specifying information is output, and the deletion packet selecting step corresponds to the number of packets included in the section belonging to the selected module and the section of the reception completion packet based on the packet specifying information. The packet filling rate of the section is calculated from the number of packets, and a packet belonging to the section having the smallest packet filling rate is selected.

  More preferably, the cache control step outputs packet specifying information when the free space of the first memory is insufficient, and the deletion packet selecting step is a section belonging to the selected module based on the packet specifying information. The packet filling rate of the section is calculated from the number of packets included in the packet and the number of packets corresponding to the section of the reception completion packets, and the packet belonging to the section with the smallest packet filling rate is selected.

  The present invention is also a data receiving program in a data receiving device including a first memory, wherein the content is divided into a plurality of packets, and the transmission data is repeatedly transmitted including the divided packets. Receiving the packet, extracting one or more packets from the transmission data, outputting them, a first memory for temporary storage, and receiving the packets to determine whether or not the packets are received normally. When the packet is normally received, and at least one of the packets of the group to which the normally received packet belongs is not normally received, a cache control step for saving the normally received packet in the first memory, and deletion A deletion packet selection step for selecting a target packet, and a cache control step When the normally received packet is stored in the first memory, if the free space of the first memory is insufficient, a deletion target selection command is output, and the deletion packet selection step receives the deletion target selection command. Then, one or more packets stored in the first memory and a reception completion packet that is a normally received packet are selected according to a predetermined condition, and are to be deleted. Is output, and the cache control step deletes the packet based on the deletion target packet information.

  More preferably, the content is divided into one or a plurality of modules, the module is divided into one or a plurality of sections, the section is divided into one or a plurality of packets, and the transmission data is one or more. The packet includes packet specifying information for specifying the packet, the group is a section, and the cache control step is a section to which the normally received packet belongs when the packet is normally received. When at least one of the packets is not normally received, the normally received packet is stored in the first memory, and the cache control step performs the processing when storing the normally received packet in the first memory. If there is not enough free space in 1 memory, it is included in the reception complete packet. , And outputs the packet identification information for deletion selection command, delete the packet selecting step, based on the packet identification information, selects one or a plurality of packets according to a predetermined condition from the received completion packet.

  More preferably, the packet identification information is the number of packets included in the module to which each reception completion packet belongs, and the cache control step outputs the packet identification information when the first memory has insufficient free space. The deletion packet selection step selects a packet belonging to the module having the maximum or minimum number of packets based on the packet specifying information.

  More preferably, the packet specifying information is the number of the module to which the reception completion packet belongs and the number of packets included in the module to which the reception completion packet belongs, and the cache control step has insufficient free space in the first memory The packet specifying information is output, and the deletion packet selecting step is performed based on the packet specifying information based on the number of packets included in the module and the number of packets corresponding to the module among the reception completion packets. And the packet belonging to the module having the smallest packet filling rate is selected.

  More preferably, the packet specifying information includes a section number to which the reception completion packet belongs and a reception completion packet number in the section, and the cache control step performs packet processing when the first memory has insufficient free space. The specific information is output, and the deletion packet selection step selects, based on the packet specific information, a packet belonging to a section in which the first packet is not normally received among the sections to which the reception completion packets belong.

  More preferably, the packet specification information is a retransmission cycle of a module to which each reception completion packet belongs, and the cache control step outputs and deletes the packet specification information when the first memory has insufficient free space. The packet selection step selects a packet belonging to the module having the maximum or minimum retransmission cycle based on the packet identification information.

  More preferably, the packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the module to which the reception completion packet belongs, respectively. The cache control step outputs packet specifying information when the first memory has insufficient free space, and the deleted packet selecting step receives the packet based on the packet specifying information. The number of packets included in the module is calculated from the number of packets included in one or more sections belonging to a module and the number of sections included in the module among the sections to which the completion packet belongs. Number of Selecting a packet belonging to a module is greater or minimum.

  More preferably, the packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the module to which the reception completion packet belongs, respectively. The cache control step outputs packet specifying information when the first memory has insufficient free space, and the deleted packet selecting step receives the packet based on the packet specifying information. The number of packets included in the module is calculated from the number of packets included in one or more sections belonging to a module and the number of sections included in the module among the sections to which the completion packet belongs. And the number of Calculating a packet sufficiency rate from the number modules corresponding packet to the module of the received completion packet, the packet fill rate selects packets belonging to a module is the minimum.

  More preferably, the packet specification information is a data amount of a module to which each reception completion packet belongs, and the cache control step outputs the packet specification information and deletes when the first memory has insufficient free space. The packet selection step selects a packet belonging to the module having the maximum or minimum data amount based on the packet specifying information.

  Preferably, the data receiving device further includes a second memory, the content is divided into one or a plurality of modules, the module is divided into one or a plurality of sections, and the section is composed of one or a plurality of sections. The transmission data is composed of one or a plurality of packets, the packet includes packet specifying information for specifying the packet, the group is a section, and the cache control step normalizes the packet. When all the packets of the section to which the normally received packet belongs are received normally when received, all the packets corresponding to the section among the packets stored in the first memory are generated and output. The data receiving program is When the section output in the cache control step is received and at least one of the sections constituting the module is not received, the packet included in the section output in the cache control step is transmitted to the second memory. When all the sections constituting the module are received, the module is generated and output, and the data reconfiguration that deletes all the packets corresponding to the module from among the packets stored in the second memory Generating and outputting a priority receiving module designation indicating a module to be preferentially received based on the module requested in the step, the browser step requesting the module including the designated browsing data, and the browser control step; Data reconstruction steps The browser request processing step for outputting the module requested in the browser control step is executed out of the modules output in the browser control step, and the browser step receives the module output in the browser request processing step, and designates the browsing The data is extracted from the module and laid out, and the layout browsing data is output. When the packet is normally received, at least one of the packets of the section to which the normally received packet belongs is normal. When not received, the normally received packet is stored in the first memory, and when the normally received packet is stored in the first memory, the cache control step has insufficient free space in the first memory. Is included in the reception complete packet. The packet specifying information is output as a deletion target selection command, and the deletion packet selecting step includes one or a plurality of packets according to a predetermined condition from among the reception completion packets based on the packet specifying information and the priority receiving module designation. Select.

  More preferably, the packet specifying information is a module number to which the reception completion packet belongs, and the cache control step outputs the packet specifying information when the first memory has insufficient free space, and performs browser request processing. The step outputs a priority reception module designation indicating a module including a startup document which is browsing data to be presented immediately after the start of the browser control step, and the deletion packet selection step is based on the packet identification information and the priority reception module designation. Packets belonging to modules other than the module indicated by the priority receiving module designation are preferentially selected for deletion.

  More preferably, the packet specifying information is a module number to which the reception completion packet belongs, and the cache control step outputs the packet specifying information when the first memory has insufficient free space, and performs browser request processing. The step outputs the priority reception module designation indicating the module including the designated browsing data, and the deletion packet selection step is performed on a module other than the module indicated by the priority reception module designation based on the packet identification information and the priority reception module designation. The packet to which it belongs is preferentially selected for deletion.

  More preferably, the content is divided into one or a plurality of components, the components are divided into one or a plurality of modules, and the data receiving program is further sent to the computer in the header of the packet output in the receiving step. Based on the included packet identifier, the number of the component to which the packet belongs is acquired, and the output carousel identification step is executed. When the normally received packet is stored in the first memory, the cache control step If there is not enough free memory, the number of the component to which the reception completion packet belongs is further output. The packet identification information is the number of the module to which the reception completion packet belongs, and the browser request processing step is specified. Including browsing data The priority reception module specification indicating the module included in the component to which the module belongs is output, and the deletion packet selection step is performed based on the packet identification information, the component number, and the priority reception module specification. A packet included in a module belonging to is preferentially selected as a deletion target.

  More preferably, the packet specifying information further includes a section number to which the reception completion packet belongs and a number of packets included in the section to which the reception completion packet belongs, and the cache control step is insufficient in the first memory free space If so, the packet specifying information is output, and the deletion packet selecting step corresponds to the number of packets included in the section belonging to the selected module and the section of the reception completion packet based on the packet specifying information. The packet filling rate of the section is calculated from the number of packets, and a packet belonging to the section having the smallest packet filling rate is selected.

  More preferably, the cache control step outputs packet specifying information when the free space of the first memory is insufficient, and the deletion packet selecting step is a section belonging to the selected module based on the packet specifying information. The packet filling rate of the section is calculated from the number of packets included in the packet and the number of packets corresponding to the section of the reception completion packets, and the packet belonging to the section with the smallest packet filling rate is selected.

  According to the data receiving apparatus, the data receiving method, and the data receiving program according to the present invention, it is possible to efficiently select a TS packet to be discarded and efficiently use a memory for temporarily storing the received TS packet.

  The data structure used in the DSM-CC data carousel transmission system in the embodiment of the present invention is the same as that shown in FIG. 11, and the concept of data transmission performed in the DSM-CC data carousel transmission system is shown in FIG. The detailed structure of the TS packet is the same as that shown in FIG.

<First Embodiment>
A data receiving apparatus according to an embodiment of the present invention will be described with reference to the drawings.

[Constitution]
[Configuration of data receiver]
FIG. 1 shows a functional block diagram of a data receiving apparatus according to the first embodiment of the present invention. Referring to the figure, this data receiving apparatus includes a tuner 1, a demodulating unit 2, a TS decoding processing unit 3, an audio decoding processing unit 4, a video decoding processing unit 5, a presentation processing unit 6, a browser, The request processing unit 7, a browser 8, a RAM (Random Access Memory) 9, and a CPU (Central Processing Unit) 10 are included.

  The tuner 1 receives a digital broadcast signal, performs frequency conversion from an RF (Radio Frequency) band to a baseband band, and outputs the baseband signal to the demodulation unit 2.

  The demodulator 2 receives the baseband signal and extracts one or a plurality of TS packets from the demodulated signal obtained by demodulating the baseband signal. Then, the demodulator 2 performs error detection processing on the TS packet, and when an error is detected, sets a flag indicating an error in the transport error indicator of the packet header.

  The TS decode processing unit 3 receives the TS packet, and based on the packet identifier of the packet header, the TS packet corresponding to the audio signal (hereinafter referred to as an audio TS packet) and the TS packet corresponding to the video signal (hereinafter referred to as the video). TS packets) and TS packets corresponding to data (hereinafter referred to as data TS packets) are identified. Then, the TS decode processing unit 3 outputs the audio TS packet to the audio decode processing unit 4 and outputs the video TS packet to the video decode processing unit 5. The TS decode processing unit 3 generates a module from a plurality of data TS packets and outputs the module to the browser request processing unit 7.

  The audio decoding processing unit 4 receives the audio TS packet, performs decompression processing on the compressed audio data, generates audio data, and outputs it to the outside.

  The video decoding processing unit 5 receives the video TS packet, performs decompression processing on the compressed video data, generates video data, and outputs the video data to the presentation processing unit 6.

  The browser request processing unit 7 receives the module from the TS decode processing unit 3 and outputs the module requested from the browser 8. Also, the browser request processing unit 7 generates a priority reception module designation indicating a module to be preferentially received based on the module number requested from the browser 8, and the TS decoding processing unit 3 in the TS decode processing unit 3 via the system bus. The data is output to the carousel reception processing unit 22.

  The browser 8 receives the module from the browser request processing unit 7 and extracts browsing data such as a BML document and image data from the module. Then, the browser 8 lays out the browsing data and outputs it to the presentation processing unit 6. Further, the browser 8 outputs a control signal to the browser request processing unit 7 via the system bus, thereby requesting the browser request processing unit 7 for a module including browsing data designated by the user or the like.

  The presentation processing unit 6 generates a presentation screen that combines the layout browsing data and the video data received from the video decoding processing unit 5, and outputs the generated presentation screen to the outside.

  The RAM 9 stores data necessary for control performed by the CPU 10.

  The CPU 10 performs various controls on each functional block via the system bus.

[Configuration of TS decode processing unit 3]
FIG. 2 is a functional block diagram of the TS decode processing unit 3 in the data receiving apparatus according to the present embodiment. Referring to FIG. 3, TS decode processing unit 3 includes a PID (Packet Identification) filter unit 21 and a carousel reception processing unit 22.

  The PID filter unit 21 receives the TS packet and identifies the audio TS packet, the video TS packet, and the data TS packet based on the packet identifier of the packet header. Here, the PID filter unit 21 receives PID information from the CPU 10 via the system bus. The PID filter unit 21 can recognize packet identifiers corresponding to the audio TS packet, the video TS packet, and the data TS packet by referring to the PID information. Then, the PID filter unit 21 outputs the audio TS packet to the audio decoding processing unit 4 and outputs the video TS packet to the video decoding processing unit 5. Further, the PID filter unit 21 outputs the data TS packet to the carousel reception processing unit 22.

  The carousel reception processing unit 22 generates a module from a plurality of data TS packets and outputs the module to the browser request processing unit 7. The carousel reception processing unit 22 receives a priority reception module designation from the browser request processing unit 7 via the system bus. The operation based on this will be described later.

[Configuration of Carousel Reception Processing Unit 22]
FIG. 3 shows a functional block diagram of the carousel reception processing unit 22 in the TS decoding processing unit 3 according to the present embodiment.

  With reference to the figure, the carousel reception processing unit 22 includes a carousel identification unit 31, an arrangement information separation unit 32, an arrangement information analysis unit 33, a cache control unit 34, a deletion packet selection unit 35, a RAM 36, A data reconstruction unit 37 and a RAM 38 are included.

  The basic operation of each functional block will be described in association with the flowchart shown in FIG. The carousel identification unit 31, the sequence information separation unit 32, the sequence information analysis unit 33, the cache control unit 34, the deletion packet selection unit 35, and the data reconstruction unit 37 read and execute a program including each step of the flowchart from a memory (not shown). To do. This program can be installed externally.

  The carousel identification unit 31 receives the data TS packet, and acquires the component (carousel) number to which the data TS packet belongs based on the packet identifier in the packet header. Then, the carousel identification unit 31 outputs this component number to the cache control unit 34. Further, the carousel identifying unit 31 outputs the data TS packet to the array information separating unit 32 (S1 and S2).

  The array information separating unit 32 receives the data TS packet, extracts the array information from the data TS packet, and outputs it to the array information analyzing unit 33. Further, the array information separating unit 32 outputs the data TS packet to the cache control unit 34 (S3).

  Here, also in the embodiment of the present invention, as in the invention described in Patent Document 1, the sequence information is transported in the option field (FIG. 13C) in the adaptation field (FIG. 13B). It is inserted in the private data area.

  Further, the array information includes information for specifying the TS packet. That is, the array information includes the number of the module to which the TS packet belongs, the version number of the module to which the TS packet belongs, the number of the DSM-CC section to which the TS packet belongs, and the last DSM-CC section constituting the module to which the TS packet belongs. The number, the number of the TS packet in the DSM-CC section to which the TS packet belongs, and the number of the last TS packet in the DSM-CC section to which the TS packet belongs are included. Note that the number of DSM-CC sections included in a module can be known from the number of the last DSM-CC section constituting the module to which the TS packet belongs. Further, the number of TS packets included in the DSM-CC section can be known from the number of the last TS packet in the DSM-CC section to which the TS packet belongs.

  Furthermore, in the array information, as information for specifying the TS packet, the number of TS packets included in the module to which the TS packet belongs, the data amount (number of bytes) of the module to which the TS packet belongs, and the retransmission of the module to which the TS packet belongs. A period is included.

  The array information only needs to include at least one piece or a plurality of pieces of information necessary for the data receiving apparatus according to the present embodiment to specify the TS packet among these pieces of information. It is not necessary for all information to be included in the sequence information.

  Here, normally, the number of TS packets included in the module, the data amount of the module, and the retransmission period of the module are information in units of modules, but these are included in the arrangement information of all TS packets belonging to the module. Yes. This is because it is unknown which TS packet can be normally received in the data receiving apparatus, so that even if which TS packet is normally received, the data receiving apparatus can recognize the information of the module to which the TS packet belongs. It is to do.

  The sequence information analysis unit 33 receives the sequence information and generates TS packet attribute information obtained by converting the information for specifying the TS packet included in the sequence information into a data format or format that can be easily processed by the cache control unit 34 or the like. And output to the cache control unit 34 (S4).

  The cache control unit 34 receives the data TS packet and determines whether or not the data TS packet includes an error based on the transport error indicator in the packet header (S5). If the data TS packet contains an error, the cache control unit 34 discards the error (S6).

  On the other hand, if the data TS packet does not contain an error (S5), the cache control unit 34 acquires TS packet attribute information corresponding to each data TS packet stored in the RAM 36, and these TSs. Based on the packet attribute information, information indicating what number data TS packet of what number DSM-CC section of what number module belonging to what number component is stored in the current RAM 36 (hereinafter referred to as “data TS packet”). , TS packet storage information) is generated (S7).

  The cache control unit 34 determines from the TS packet storage information that all the data TS packets belonging to a certain DSM-CC section are not prepared by the data TS packet normally received this time (S8) and is free in the RAM 36. If there is (S9), the data TS packet is stored in the RAM 36 based on the component number received from the carousel identifying unit 31 and the TS packet attribute information received from the array information analyzing unit 33. The cache control unit 34 also stores TS packet attribute information corresponding to the data TS packet to be stored in the RAM 36 (S11).

  However, the cache control unit 34 determines from the TS packet storage information, and when the data TS packet with the same number in the DSM-CC section with the same number belonging to the component with the same number is already stored in the RAM 36 (S10). The data TS packet and TS packet attribute information normally received this time are discarded without being overwritten in the RAM 36 (S6).

  On the other hand, the cache control unit 34 determines from the TS packet storage information that the data TS packet normally received this time does not contain all the data TS packets belonging to a certain DSM-CC section, and the free space of the RAM 36. If the packet is insufficient (S9), the TS packet attribute information stored in the RAM 36, the TS packet attribute information corresponding to the data TS packet normally received this time, and the TS packet storage information are output to the deletion packet selector 35. The normally received data TS packet is held (S12).

  Based on the TS packet storage information, the TS packet attribute information, and the priority reception module designation received from the browser request processing unit 7, the deletion packet selection unit 35 is optimal as a deletion target from among the data TS packets stored in the RAM 36. One or a plurality of data TS packets (hereinafter referred to as deletion target packets) are selected, and deletion target packet information is output to the cache control unit 34 (S13).

  The cache control unit 34 receives the deletion target packet information and deletes the corresponding data TS packet from the RAM 36 (S14). Further, when the held data TS packet is not to be deleted (S15), the cache control unit 34 stores it in the RAM 36 (S16).

  Note that deleting the data TS packet stored in the RAM 36 means a process of setting all the bits of data in the data TS packet to a logic high level.

  On the other hand, when the cache control unit 34 determines that all the data TS packets belonging to a certain DSM-CC section are prepared by the received data TS packet, all the data TS packets belonging to the DSM-CC section are The section number, module number, and component number to which these belong are output to the data reconstruction unit 37 (S17).

  Then, the cache control unit 34 deletes all the data TS packets corresponding to the DSM-CC section output to the data reconstruction unit 37 among the data TS packets stored in the RAM 36 (S17).

  If the DSM-CC section received this time does not include all DSM-CC sections belonging to a certain module (S18), the data reconfiguration unit 37 receives the section number, module number, and component received from the cache control unit 34. Based on the number, the data TS packet constituting the DSM-CC section received from the cache control unit 34 is stored in the RAM 38 (S19).

  On the other hand, when all the DSM-CC sections belonging to a certain module are prepared by the DSM-CC section received this time (S18), the data reconfiguration unit 37 generates a module from these DSM-CC sections, The number and the module number are output to the browser request processing unit 7 in the data receiving apparatus shown in FIG. 1 (S20).

  Then, the data reconstruction unit 37 deletes all the data TS packets corresponding to the module output to the browser request processing unit 7 from the data TS packets stored in the RAM 38 (S20).

[Operation]
Data reception according to the present embodiment until the deletion packet selection unit 35 selects one or more optimum data TS packets to be deleted from the data TS packets stored in the RAM 36 The operation of each functional block of the apparatus will be described.

  FIG. 5 shows an example of the retransmission period, the number of sections, and the number of TS packets of the last DSM-CC section (hereinafter referred to as the last section) of each module constituting the component # 80 whose component number is 80.

  Referring to the figure, component # 80 is composed of module # 0, module # 1, and module # 2. Module # 0 has a retransmission period of 10, is composed of two DSM-CC sections, and the final section includes four data TS packets. Module # 1 has a retransmission period of 20, is composed of four DSM-CC sections, and the final section includes two data TS packets. Module # 2 has a retransmission period of 30, is composed of three DSM-CC sections, and the final section includes one data TS packet. It is assumed that the DSM-CC sections other than the last section include four data TS packets.

  FIG. 6 is a conceptual diagram showing the transmission order of the DSM-CC sections constituting the component # 80.

  Similarly to FIG. 12, the Z-th DSM-CC section belonging to the module Y transmitted by the component (carousel) X is represented by DSM-CC section X · YZ.

  First, the DSM-CC section 80 • 00 and the DSM-CC section 80 • 01 constituting the module # 0 are transmitted. Next, DSM-CC sections 80 and 10, DSM-CC sections 80 and 11, DSM-CC sections 80 and 12, and DSM-CC sections 80 and 13 constituting module # 1 are transmitted. Next, DSM-CC sections 80 and 20, DSM-CC sections 80 and 21 and DSM-CC sections 80 and 22 constituting module # 2 are transmitted.

  A case where the reception result of the data TS packet belonging to the component # 80 is as shown in FIG. Note that the capacity of the RAM 36 is assumed to be 14 TS packets.

  First, the transmitting apparatus transmits a digital broadcast signal corresponding to the first data TS packet belonging to the DSM-CC section 80 • 00 to the data receiving apparatus according to the present embodiment. Hereinafter, the first to fourth data TS packets belonging to the DSM-CC section are referred to as data TS packet # 0 to data TS packet # 3, respectively.

  The tuner 1 and the demodulator 2 extract TS packets from the digital broadcast signal and output the TS packets to the TS decode processor 3. Since the TS packet does not include an error, the demodulator 2 does not set a flag indicating the error in the transport error indicator of the packet header.

  The PID filter unit 21 in the TS decode processing unit 3 receives the TS packet and recognizes that the TS packet is a data TS packet based on the packet identifier and the PID information in the packet header. Then, the PID filter unit 21 outputs the data TS packet to the carousel reception processing unit 22.

  The carousel identification unit 31 in the carousel reception processing unit 22 receives the data TS packet, and acquires the component number # 80 of the component to which the data TS packet belongs based on the packet identifier of the packet header. Then, the carousel identification unit 31 outputs the component number # 80 to the cache control unit 34. In addition, the carousel identifying unit 31 outputs the data TS packet to the array information separating unit 32.

  The array information separating unit 32 receives the data TS packet, extracts the array information from the data TS packet, and outputs it to the array information analyzing unit 33. In addition, the array information separation unit 32 outputs the data TS packet to the cache control unit 34.

  The sequence information analysis unit 33 receives the sequence information and analyzes it, and outputs TS packet attribute information indicating each information included in the sequence information to the cache control unit 34.

  Here, from FIG. 5 and FIG. 6, the arrangement information of this data TS packet, that is, the TS packet attribute information, the module number to which the TS packet belongs is 0, the DSM-CC section number to which the TS packet belongs is 0, TS packet The last DSM-CC section number constituting the module to which the TS packet belongs is 1, the TS packet number in the DSM-CC section to which the TS packet belongs is 0, and the last TS packet number in the DSM-CC section to which the TS packet belongs is 3. The number of TS packets constituting the module is 8, and the retransmission period of the module is 10.

  The cache control unit 34 receives the data TS packet, and determines that the error is not included in the data TS packet because the error flag is not set in the transport error indicator of the packet header.

  Then, the cache control unit 34 recognizes that the data TS packet belongs to the component # 80 from the component number received from the carousel identification unit 31. Furthermore, the cache control unit 34 recognizes that the data TS packet is the data TS packet # 0 belonging to the DSM-CC section # 0 of the module # 0 based on the TS packet attribute information received from the array information analysis unit 33. To do.

  Then, the cache control unit 34 stores the data TS packet in the RAM 36.

  Further, the cache control unit 34 determines that the last DSM-CC section of the module # 0 to which the data TS packet belongs is the DSM-CC section # 1 based on the TS packet attribute information received from the array information analysis unit 33. That is, it is recognized that the number of DSM-CC sections in module # 0 is two. Further, the cache control unit 34 determines that the last data TS packet of the DSM-CC section # 0 of the module # 0 to which the data TS packet belongs is the data TS packet # 3, that is, the DSM-CC section # 0. It is recognized that the number of TS packets in is 4.

  Next, the transmitting apparatus transmits a digital broadcast signal corresponding to data TS packet # 1 belonging to the DSM-CC section 80 • 00 to the data receiving apparatus according to the present embodiment.

  As in the case of the data TS packet # 0 belonging to the DSM-CC section 80 • 00 described above, the cache control unit 34 receives the data TS packet # 1. The cache control unit 34 determines that this data TS packet contains an error because the flag indicating the error is set in the transport error indicator of the packet header, and discards this.

  Next, the transmitting apparatus transmits a digital broadcast signal corresponding to data TS packet # 2 belonging to the DSM-CC section 80.00 to the data receiving apparatus according to the present embodiment.

  As in the case of the data TS packet # 0 belonging to the DSM-CC section 80 • 00 described above, the cache control unit 34 receives the data TS packet # 2. Then, the cache control unit 34 determines that no error is included in this data TS packet because no flag indicating an error is set in the transport error indicator of the packet header.

  Then, the cache control unit 34 recognizes that the data TS packet belongs to the component # 80 from the component number received from the carousel identification unit 31. Furthermore, the cache control unit 34 recognizes that the data TS packet is the data TS packet # 2 belonging to the DSM-CC section # 0 of the module # 0 based on the TS packet attribute information received from the array information analysis unit 33. To do.

  Then, the cache control unit 34 stores the data TS packet in the RAM 36.

  Next, the transmitting apparatus transmits a digital broadcast signal corresponding to data TS packet # 3 belonging to the DSM-CC section 80.00 to the data receiving apparatus according to the present embodiment.

  As in the case of the data TS packet # 0 belonging to the DSM-CC section 80 • 00 described above, the cache control unit 34 receives the data TS packet # 3. Then, the cache control unit 34 determines that no error is included in this data TS packet because no flag indicating an error is set in the transport error indicator of the packet header.

  Then, the cache control unit 34 recognizes that the data TS packet belongs to the component # 80 from the component number received from the carousel identification unit 31. Further, the cache control unit 34 recognizes that the data TS packet is the data TS packet # 3 belonging to the DSM-CC section # 0 of the module # 0 based on the TS packet attribute information received from the array information analysis unit 33. To do.

  Then, the cache control unit 34 stores the data TS packet in the RAM 36.

  Here, as described above, the cache control unit 34 determines that the last data TS packet of the DSM-CC section 80 • 00 to which the data TS packet belongs is the data TS packet # 3 based on the TS packet attribute information. It has recognized. Therefore, the cache control unit 34 determines whether all the data TS packets belonging to the DSM-CC section 80.00 are prepared with reference to the TS packet storage information. Then, since the data TS packet # 1 of the DSM-CC section 80 • 00 is not received, that is, not stored in the RAM 36, the data TS packet # 0, the data TS packet # 2 belonging to the DSM-CC section 80 • 00, and The data TS packet # 3 remains stored in the RAM 36.

  Next, the transmitting apparatus transmits a digital broadcast signal corresponding to the DSM-CC section 80 • 01 to the data receiving apparatus according to the present embodiment.

  Similarly to the case of the DSM-CC section 80 • 00, the cache control unit 34 does not include an error in the data TS packet # 0 and the data TS packet # 1 belonging to the DSM-CC section 80 • 01. Save to. Since data TS packet # 2 and data TS packet # 3 contain an error, they are discarded. In this case, since the data TS packet # 2 and the data TS packet # 3 are not received, the data TS packet # 2 and the data TS packet # 3 belonging to the DSM-CC section 80 • 01 remain stored in the RAM 36. .

  Next, the transmitting apparatus transmits a digital broadcast signal corresponding to the DSM-CC sections 80 and 10 to the data receiving apparatus according to the present embodiment.

  Similarly to the above, the cache control unit 34 stores the data TS packet # 3 belonging to the DSM-CC sections 80 and 10 in the RAM 36 because no error is included. Since data TS packet # 0, data TS packet # 1, and data TS packet # 2 contain errors, they are discarded. In this case, since the data TS packet # 0, the data TS packet # 1, and the data TS packet # 2 are not received, the data TS packet # 3 belonging to the DSM-CC sections 80 and 10 remains stored in the RAM 36. .

  Next, the transmitting apparatus transmits a digital broadcast signal corresponding to the DSM-CC sections 80 and 11 to the data receiving apparatus according to the present embodiment.

  Similarly to the above, the cache control unit 34 stores the data TS packet # 0 to data TS packet # 2 belonging to the DSM-CC sections 80 and 11 in the RAM 36 because no error is included.

  Next, the cache control unit 34 determines that an error is not included in the data TS packet # 3 belonging to the DSM-CC sections 80 and 11.

  Here, as described above, the cache control unit 34 determines that the last data TS packet of the DSM-CC sections 80 and 11 to which this data TS packet belongs is the data TS packet # 3 based on the TS packet attribute information. It has recognized. Therefore, the cache control unit 34 determines from the TS packet storage information that all data TS packets belonging to the DSM-CC sections 80 and 11 are prepared by the received data TS packet # 3.

  Then, the cache control unit 34 outputs the data TS packet # 0 to data TS packet # 3 belonging to the DSM-CC sections 80 and 11 to the data reconfiguration unit 37.

  Then, the cache control unit 34 deletes the data TS packet # 0 to data TS packet # 2 belonging to the DSM-CC sections 80 and 11 from the RAM 36.

  Next, the transmission side apparatus transmits a digital broadcast signal corresponding to the DSM-CC sections 80 and 12 to the data reception apparatus according to the present embodiment.

  Similarly to the above, the cache control unit 34 stores the data TS packet # 0 and data TS packet # 1 belonging to the DSM-CC sections 80 and 12 in the RAM 36 because no error is included. Since data TS packet # 2 and data TS packet # 3 contain an error, they are discarded. In this case, since the data TS packet # 2 and the data TS packet # 3 are not received, the data TS packet # 0 and the data TS packet # 1 belonging to the DSM-CC sections 80 and 12 remain stored in the RAM 36. .

  Next, the transmitting apparatus transmits a digital broadcast signal corresponding to the DSM-CC sections 80 and 13 to the data receiving apparatus according to the present embodiment.

  Similarly to the above, the cache control unit 34 stores the data TS packet # 0 belonging to the DSM-CC sections 80 and 13 in the RAM 36 because no error is included. Since the data TS packet # 1 includes an error, it is discarded.

  Here, as described above, the cache control unit 34 determines that the last data TS packet of the DSM-CC sections 80 and 13 to which the data TS packet belongs is the data TS packet # 1 based on the TS packet attribute information. It has recognized. Accordingly, the cache control unit 34 determines whether all the data TS packets belonging to the DSM-CC sections 80 and 13 are prepared with reference to the TS packet storage information. Then, since the data TS packet # 1 of the DSM-CC sections 80 and 13 is not received, the data TS packet # 0 belonging to the DSM-CC sections 80 and 13 remains stored in the RAM 36.

  Next, the transmitting apparatus transmits a digital broadcast signal corresponding to the DSM-CC sections 80 and 20 to the data receiving apparatus according to the present embodiment.

  Similarly to the above, the cache control unit 34 stores the data TS packet # 0, data TS packet # 1, and data TS packet # 2 belonging to the DSM-CC sections 80 and 20 in the RAM 36 because no error is included. To do. Since the data TS packet # 3 includes an error, it is discarded. In this case, since the data TS packet # 3 is not received, the data TS packet # 0, the data TS packet # 1, and the data TS packet # 2 belonging to the DSM-CC sections 80 and 20 remain stored in the RAM 36. Become.

  Next, the transmission side apparatus transmits a digital broadcast signal corresponding to the DSM-CC sections 80 and 21 to the data reception apparatus according to the present embodiment.

  Similarly to the above, the cache control unit 34 stores the data TS packet # 0 and data TS packet # 1 belonging to the DSM-CC sections 80 and 21 in the RAM 36 because no error is included.

  Next, the cache control unit 34 generates TS packet storage information because the data TS packet # 2 belonging to the DSM-CC sections 80 and 21 does not include an error. Then, from this TS packet storage information, the cache control unit 34 does not have all the data TS packets belonging to the DSM-CC sections 80 and 21 even by the data TS packet # 2 normally received this time, and the RAM 36 stores , 14 data TS packets are stored, and it is recognized that the free space of the RAM 36 is insufficient. In this case, either the currently received data TS packet # 2 or the data TS packet stored in the RAM 36 must be discarded. Therefore, the cache control unit 34 outputs the current TS packet storage information of the RAM 36 to the deletion packet selection unit 35, and holds the data TS packet # 2 normally received this time. Further, the cache control unit 34 outputs the TS packet attribute information of the data TS packet # 2 normally received this time and the TS packet attribute information stored in the RAM 36 to the deletion packet selecting unit 35 together with the TS packet storage information.

[Operation of Delete Packet Selection Unit 35]
Next, an operation in which the deletion packet selection unit 35 selects a deletion target packet from the data TS packets stored in the RAM 36 will be described.

  In the following method 1 to method 4, the deletion packet selection unit 35 selects a deletion target packet based on the TS packet storage information and the TS packet attribute information received from the cache control unit 34.

[Method 1]
The deletion packet selection unit 35 selects a module to be deleted on the basis of the number of TS packets included in the module (hereinafter referred to as module packet size). Further, the deletion packet selection unit 35 calculates the TS packet filling rate (hereinafter referred to as a packet filling rate) of the DSM-CC section, and uses this as a reference from among the DSM-CC sections belonging to the module to be deleted. The DSM-CC section to be deleted is selected. Then, the deletion packet selection unit 35 designates a deletion target packet in units of DSM-CC sections, that is, sets all data TS packets belonging to the deletion target DSM-CC section as deletion target packets.

  In the case shown in FIG. 7, the module packet size of module # 0 is 8 TS packets, the module packet size of module # 1 is 14 TS packets, and the module packet size of module # 2 is TS packets. Nine. Therefore, the deletion packet selection unit 35 selects the module # 0 having the smallest module packet size among the modules # 0 to # 2 belonging to the component # 80 as a deletion target module.

  Here, the packet filling rate of DSM-CC section # 0 belonging to module # 0 is 3/4, and the packet filling rate of DSM-CC section # 1 is 2/4. Therefore, the deletion packet selection unit 35 selects the DSM-CC section # 1 having the smallest packet filling rate as the DSM-CC section to be deleted.

  The deletion packet selection unit 35 then outputs to the cache control unit 34 deletion target packet information indicating that all data TS packets belonging to the DSM-CC section # 1 of the deletion target module # 0 are to be the deletion target packets. To do.

  Since a module having a large size has a large number of data TS packets, the module is completed, that is, the time until all the data TS packets are arranged tends to be longer than that of a module having a small size. Therefore, by preferentially leaving the large module in the RAM 36, it is possible to prevent the large module from being frequently deleted and taking a long time to complete.

  In addition, a DSM-CC section with a high packet filling rate is likely to have a shorter time to completion than a DSM-CC section with a low packet filling rate. Therefore, by preferentially storing the DSM-CC section having a high filling rate in the RAM 36, it becomes easy to secure a free space in the RAM 36, and the RAM 36 can be used efficiently.

  Next, a case where the module packet size is not included in the array information, that is, the TS packet attribute information, and the deletion packet selection unit 35 cannot recognize the module packet size will be described.

  In this case, as described above, the deletion packet selection unit 35 knows the number of TS packets included in the DSM-CC section from the number of the last data TS packet in the DSM-CC section to which the data TS packet belongs. Therefore, when all of the DSM-CC sections belonging to a module have normally received at least one data TS packet belonging to the DSM-CC section, the deletion packet selection unit 35 sets each DSM-CC section to each DSM-CC section. By summing the number of TS packets included, each module packet size can be recognized.

  However, in the case shown in FIG. 7, since the data receiving apparatus has not received the data TS packet belonging to the DSM-CC section # 2 of the module # 2, the deletion packet selecting unit 35 performs the DSM-CC section # 2. The number of TS packets included in is not known.

  In this case, since the DSM-CC section # 0 or the DSM-CC section # 1 has normally received at least one data TS packet included therein, the number of TS packets included in the DSM-CC section is clear. It has become. Further, as described above, the deletion packet selection unit 35 knows the number of DSM-CC sections included in the module by the number of the last DSM-CC section constituting the module to which the data TS packet belongs.

  Therefore, the deletion packet selection unit 35 can estimate the module packet size using these values. That is, since the number of DSM-CC sections included in the module is two in the deletion packet selection unit 35, the DSM-CC section that has not been received by the module # 2 is only the DSM-CC section # 2. Recognize Then, the deletion packet selection unit 35 regards the number of TS packets included in the DSM-CC section # 2 as the same four as the DSM-CC section # 0 and the DSM-CC section # 1, and the module packet size of the module # 2. Is estimated to be 12 TS packets.

  When a plurality of DSM-CC sections belonging to a module are normally received and the number of TS packets included in these sections is different, the number of TS packets included in any one DSM-CC section is determined. The number of TS packets included in an unreceived DSM-CC section may be considered. Alternatively, an average value of the number of TS packets included in a plurality of DSM-CC sections may be regarded as the number of TS packets included in an unreceived DSM-CC section.

  As described above, even when the module packet size is not included in the array information, the deletion packet selection unit 35 can estimate the module packet size, but in order to accurately grasp the module packet size, It is desirable that the arrangement information and the TS packet attribute information include the number of TS packets included in the module.

[Method 2]
The deletion packet selection unit 35 calculates a module fullness rate, and selects a module to be deleted on the basis of this. Further, the deletion packet selection unit 35 calculates a packet filling rate, and selects a DSM-CC section to be deleted from DSM-CC sections belonging to the module to be deleted based on this packet filling rate. Then, the deletion packet selection unit 35 designates a data TS packet as a deletion target packet in units of DSM-CC sections.

  Here, when a plurality of DSM-CC sections have the same packet filling rate, the currently received DSM-CC section is one of the plurality of DSM-CC sections having the same packet filling rate, If the data TS packet held in the cache control unit 34 is not the last data TS packet of the DSM-CC section, the currently received DSM-CC section is excluded from the deletion target. This is because the DSM-CC section currently being received may have a higher fullness rate, and further, all the data TS packets of the DSM-CC section may be prepared.

  In the case shown in FIG. 7, the packet fullness rate of module # 0 is 5/8, the packet fullness rate of module # 1 is 8/14, and the packet fullness rate of module # 2 is 6/9. is there. Therefore, the deletion packet selection unit 35 selects the module # 1 having the smallest packet filling rate as a module to be deleted.

  Here, the packet filling rate of the DSM-CC section # 0 belonging to the module # 1 is 1/4, the packet filling rate of the DSM-CC section # 1 is 4/4, and the DSM-CC section # 2 Is 2/4, and the packet filling rate of DSM-CC section # 3 is 1/2. Therefore, the deletion packet selection unit 35 selects the DSM-CC section # 0 having the smallest packet filling rate as the DSM-CC section to be deleted.

  Then, the deletion packet selection unit 35 outputs to the cache control unit 34 deletion target packet information indicating that all data TS packets belonging to the DSM-CC section # 0 of the deletion target module # 1 are to be deletion target packets. To do.

  Next, the module packet size is not included in the array information, that is, the TS packet attribute information, and the deletion packet selection unit 35 cannot recognize the module packet size and cannot calculate the module fullness rate. The case will be described.

  In this case, as described in the method 1, the deletion packet selection unit 35 can recognize each module packet size by summing the number of TS packets included in each DSM-CC section of the module. Satisfaction rate can be calculated.

  However, in the case shown in FIG. 7, since the data receiving apparatus has not received the data TS packet belonging to the DSM-CC section # 2 of the module # 2, the deletion packet selecting unit 35 performs the DSM-CC section # 2. The number of TS packets included in is not known.

  In this case, as described in the method 1, the deletion packet selection unit 35 recognizes that the DSM-CC section that has not been received by the module # 2 is only the DSM-CC section # 2. Then, the deletion packet selection unit 35 regards the number of TS packets included in the DSM-CC section # 2 as the same four as other DSM-CC sections, and sets the module packet size of the module # 2 as 12 TS packets. Approximate.

  Then, the packet fullness rate of module # 2 becomes 6/12. Further, as described above, the packet filling rate of module # 0 is 5/8, and the packet filling rate of module # 1 is 8/14. Therefore, the deletion packet selection unit 35 selects module # 2 having the smallest packet filling rate as a module to be deleted.

  Here, the packet filling rate of the DSM-CC section # 0 belonging to the module # 2 is 3/4, and the packet filling rate of the DSM-CC section # 1 includes the currently held data TS packet # 2. 3/4. Here, although the packet filling rates of the DSM-CC section # 0 and the DSM-CC section # 1 are the same, the deletion packet selection unit 35 determines that the currently received DSM-CC section # 1 is to be deleted. Without selecting DSM-CC section # 0 as the DSM-CC section to be deleted. This is because, as described above, the DSM-CC section # 1 may have all the data TS packets by normally receiving the data TS packet # 3.

[Method 3]
The deletion packet selection unit 35 selects a DSM-CC section that has not received the data TS packet # 0 as a DSM-CC section to be deleted.

  Then, when there are a plurality of DSM-CC sections to be deleted, the deletion packet selection unit 35 calculates a module fullness rate, and selects a DSM-CC section belonging to the module to be deleted based on this. Further, even when there are a plurality of DSM-CC sections to be deleted, the deletion packet selection unit 35 further calculates a packet satisfaction rate when there are a plurality of DSM-CC sections to be deleted. -Select the CC section.

  In the case illustrated in FIG. 7, the deletion packet selection unit 35 selects the DSM-CC section # 0 of the module # 1 in which the data TS packet # 0 has not been received as the DSM-CC section to be deleted.

  Then, the deletion packet selection unit 35 outputs to the cache control unit 34 deletion target packet information indicating that all data TS packets belonging to the DSM-CC section # 0 of the deletion target module # 1 are to be deletion target packets. To do.

  As shown in FIG. 11, the data TS packet # 0 includes a section header of the DSM-CC section. The section header may include information that is not in the packet header of the data TS packet. For example, if the data receiver can determine that a certain DSM-CC section does not need to be currently received by the data receiver according to the information included in the section header, the data TS packet # 0 is received. Therefore, the RAM 36 can be used efficiently by preferentially storing the DSM-CC section that has been found to be necessary in the RAM 36.

[Method 4]
The deletion packet selection unit 35 selects a module to be deleted on the basis of the module retransmission period. Further, the deletion packet selection unit 35 calculates a packet filling rate, and selects a DSM-CC section to be deleted from DSM-CC sections belonging to the module to be deleted based on this packet filling rate.

  In the case shown in FIG. 7, the retransmission cycle of module # 0 is 10, the retransmission cycle of module # 1 is 20, and the retransmission cycle of module # 2 is 30. Accordingly, the deletion packet selection unit 35 selects module # 2 having the longest module retransmission cycle as a module to be deleted.

  Next, the deletion packet selection unit 35 selects the DSM-CC section # 0 as the deletion target DSM-CC section, as in the case of the method 2 described above.

  Here, a module with a short retransmission cycle is more likely to have all data TS packets within a certain period than a module with a long retransmission cycle. By preferentially storing modules that are highly likely to have data TS packets within a certain period of time, there is a high possibility that an empty space will be generated in the RAM 36 upon completion of the DSM-CC section. If the retransmission cycle is long, the reception environment may be improved when the module is retransmitted. Therefore, it is possible to avoid occupying the RAM 36 for a long time by a module having a long retransmission cycle by selecting a module having a long retransmission cycle as a deletion target.

[Method 5]
In the method 5, the deletion packet selection unit 35 determines the packet to be deleted based on the TS packet storage information and TS packet attribute information received from the cache control unit 34 and the priority reception module designation received from the browser request processing unit 7. Make a selection.

  The priority reception module designation from the browser request processing unit 7 is caused by the operation of the user browsing the content. That is, when the user performs an operation of referring to another BML document, a transition of the BML document occurs, and the browser 8 requests the browser request processing unit 7 for a module including the transition destination BML document. Here, the component to which the module including the transition destination BML document belongs is referred to as a viewing component.

  In the data broadcasting service of digital terrestrial broadcasting, immediately after the browser 8 is activated, a BML document (hereinafter referred to as a startup document) included in the module # 0 belonging to the component having the component number 80, which is an entry component, is presented. That is, it is necessary to output the presentation screen of the BML document from the presentation processing unit 6. Therefore, immediately after the browser 8 is started, the module # 0 of the component # 80 becomes a module requested by the browser 8. Then, the data TS packet belonging to the module # 0 of the component # 80 is preferentially stored in the RAM 36.

  After the start-up document presentation screen is output, the priority order of the modules, that is, the order of the modules preferentially stored in the RAM 36, is the module requested by the browser 8 first and the viewing other than the module requested by the browser 8. Modules belonging to the middle component, and thirdly, modules belonging to components other than the viewing component. The browser request processing unit 7 generates a priority reception module designation indicating the priority order and outputs it to the deletion packet selection unit 35.

  Here, the deletion packet selection unit 35 needs to recognize the component number to which the data TS packet belongs. In this case, the cache control unit 34 stores the TS packet attribute information corresponding to the data TS packet in the RAM 36. At this time, the component number to which the data TS packet belongs is also stored as TS packet storage information.

  Further, when there are a plurality of modules to be deleted, the deletion packet selection unit 35 calculates a module fullness rate and selects a module to be deleted on the basis of this. Then, the deletion packet selection unit 35 calculates the packet filling rate, and selects the DSM-CC section to be deleted from the DSM-CC sections belonging to the module to be deleted based on this packet filling rate. Then, the deletion packet selection unit 35 designates a deletion target packet in units of DSM-CC sections.

  Here, a case where the data receiving apparatus receives a component # 8B as shown in FIGS. 8 and 9 in addition to the above-described component # 80 as shown in FIGS. 5 and 6 will be described.

  FIG. 8 shows an example of the retransmission period, the number of sections, and the number of TS packets in the last section of each module constituting component # 8B.

  Referring to FIG. 8, component # 8B is composed of module # 0 and module # 1. Module # 0 has a retransmission period of 20, is composed of three DSM-CC sections, and the final section includes two data TS packets. Module # 1 has a retransmission period of 25, is composed of two DSM-CC sections, and the final section includes three data TS packets. It is assumed that the DSM-CC sections other than the last section include four data TS packets.

  FIG. 9 is a conceptual diagram showing the transmission order of the DSM-CC sections constituting the component # 8B.

  Similarly to FIG. 12, the Z-th DSM-CC section belonging to the module Y transmitted by the component (carousel) X is represented by DSM-CC section X · YZ.

  First, DSM-CC section 8B • 00, DSM-CC section 8B • 01, and DSM-CC section 8B • 02 constituting module # 0 are transmitted. Next, the DSM-CC sections 8B and 10 and the DSM-CC sections 8B and 11 constituting the module # 1 are transmitted.

  The case where the reception results of the data TS packets belonging to the component # 80 and the component # 8B are as shown in FIG. 10 on the premise of the contents of FIGS. Since the operation of each functional block in the data receiving apparatus when storing these data TS packets in the RAM 36 is basically the same as that described with reference to FIG. 7, the free space of the RAM 36 is insufficient here. I will explain from the time. Note that the capacity of the RAM 36 is assumed to be 20 TS packets.

  The transmitting device transmits a digital broadcast signal corresponding to the DSM-CC sections 80 and 21 to the data receiving device according to the present embodiment.

  The cache control unit 34 stores the data TS packet # 0 and data TS packet # 1 belonging to the DSM-CC sections 80 and 21 in the RAM 36 because no error is included.

  Next, the cache control unit 34 generates TS packet storage information because the data TS packet # 2 belonging to the DSM-CC sections 80 and 21 does not include an error. Then, from this TS packet storage information, the cache control unit 34 does not have all the data TS packets belonging to the DSM-CC sections 80 and 21 even by the data TS packet # 2 normally received this time, and the RAM 36 stores , 20 data TS packets are stored, and it is recognized that the free space of the RAM 36 is insufficient. In this case, either the currently received data TS packet # 2 or the data TS packet stored in the RAM 36 must be discarded. Therefore, the cache control unit 34 outputs the current TS packet storage information of the RAM 36 to the deletion packet selection unit 35, and holds the data TS packet # 2 normally received this time. Further, the cache control unit 34 outputs the TS packet attribute information of the data TS packet # 2 normally received this time and the TS packet attribute information stored in the RAM 36 to the deletion packet selecting unit 35 together with the TS packet storage information.

  At this time, it is assumed that the browser 8 requests the module # 0 of the component # 8B. Then, the component being viewed becomes component # 8B. Then, the browser request processing unit 7 uses, as module priority, first module # 0 belonging to the viewing component # 8B requested by the browser 8, second module # 1 belonging to the viewing component # 8B, third The priority reception module designation indicating the module # 1 and the module # 2 of the component # 80, which is a module belonging to a component other than the component being viewed, is output to the deletion packet selector 35. Here, the module # 0 of the component # 80 is excluded from the priority receiving module designation because all the data TS packets belonging to the module # 80 have been normally received and are output to the browser request processing unit 7.

  Since the deletion packet selection unit 35 determines from the TS packet storage information, the TS packet attribute information, and the priority reception module designation, the two modules # 1 and # 2 of the component # 80 are candidates for deletion. These packet filling rates are calculated. And the packet fullness rate of module # 1 is 8/14, and the packet fullness rate of module # 2 is 4/9. Therefore, the deletion packet selection unit 35 selects module # 2 having the smallest packet filling rate as a module to be deleted.

  Next, the packet filling rate of DSM-CC section # 0 belonging to module # 2 is 2/4, the packet filling rate of DSM-CC section # 1 is 3/4, and DSM-CC section # 2 Has not yet received the data TS packet and has not been saved in the RAM 36, it is not subject to deletion. Therefore, the deletion packet selection unit 35 selects the DSM-CC section # 0 having the smallest packet filling rate as the DSM-CC section to be deleted.

  Then, the deletion packet selection unit 35 performs cache control on deletion target packet information indicating that all data TS packets belonging to the DSM-CC section # 0 of the module # 2 of the component # 80 to be deleted are set as deletion target packets. To the unit 34.

  As described above, in the method 5, the module requested by the browser 8 is preferentially stored in the RAM 36, so that the waiting time of the user until the presentation screen is displayed can be reduced.

  By the way, in the data transmission device, the data reception device, the data transmission method, the data reception method, and the data transmission and data reception program described in Patent Document 1, the TS packet to be discarded is appropriately selected, and the received TS packet is temporarily stored. For this reason, there is a drawback in that a configuration for efficiently using the memory is not provided.

  However, in the data receiving apparatus according to the present embodiment, when the memory capacity is insufficient, an optimum TS packet as a deletion target is selected based on TS packet attribute information, TS packet storage information, and a request from the browser. By selecting and deleting, a TS packet to be discarded can be appropriately selected, and a memory for temporarily storing the received TS packet can be used efficiently.

[Modification]
The present invention is not limited to the above embodiment, and includes, for example, the following modifications.

[Modification 1]
In the cache control unit 34 in the data receiving apparatus according to the first embodiment of the present invention, TS packet attribute information stored in the RAM 36, TS packet attribute information corresponding to the data TS packet received normally this time, and TS packet storage Although the configuration is such that the information is output to the deletion packet selection unit 35, the present invention is not limited to this. The cache control unit 34 outputs only the TS packet attribute information corresponding to the data TS packet normally received this time and the TS packet attribute information corresponding to each data TS packet stored in the RAM 36 to the deletion packet selection unit 35. The deletion packet selection unit 35 generates TS packet storage information based on the TS packet attribute information, and selects a data TS packet to be deleted together with other information included in the TS packet attribute information. Can do.

[Modification 2]
The cache control unit 34 in the data receiving apparatus according to the first embodiment of the present invention is configured to output the TS packet storage information and the TS packet attribute information to the deletion packet selection unit 35. However, the present invention is not limited to this. Absent. The cache control unit 34 may be configured to output only the information required by the deletion packet selection unit 35. As described above, the TS packet storage information is not necessarily output by the cache control unit 34.

[Modification 3]
In the cache control unit 34 in the data receiving device according to the first embodiment of the present invention,
When no error is included in the data TS packet, the TS packet storage information is generated. However, the present invention is not limited to this. The cache control unit 34 stores information corresponding to the TS packet storage information and updates the information when the data TS packet is stored and deleted in the RAM 36. Access time can be shortened.

[Modification 4]
In the deletion packet selection unit 35 in the data receiving apparatus according to the first embodiment of the present invention, a deletion target packet is designated in units of DSM-CC sections, that is, all the data TSs belonging to the DSM-CC section to be deleted Although the packet is set as a packet to be deleted, the present invention is not limited to this. The deletion packet selection unit 35 can set all data TS packets belonging to the module as deletion target packets. By deleting data having a larger size from the RAM 36, it is possible to secure a free space in the RAM 36, and the cache control unit 34 and the deletion packet selection unit 35 can select and delete data TS packets to be deleted. Therefore, it is possible to prevent an increase in processing load on the data receiving apparatus due to frequent execution.

[Modification 5]
The deletion packet selection unit 35 in the data receiving apparatus according to the first embodiment of the present invention is configured to specify a deletion target packet in units of DSM-CC sections, but is not limited to this. Even when the deletion packet selection unit 35 selects a DSM-CC section or module as a deletion target, one or a plurality of data TS packets belonging to these can be specified as the deletion target. By deleting data having a smaller size from the RAM 36, it is possible to prevent the waste of having to normally receive data TS packets that have already been successfully received, and efficiently generate DSM-CC sections and modules. Can do.

[Modification 6]
In the arrangement information separating unit 32 in the data receiving apparatus according to the first embodiment of the present invention, the data TS packet is sent to the cache control unit 34, and the cache control unit 34 stores the data TS packet in the RAM 36. However, the present invention is not limited to this. The array information separation unit 32 extracts only the payload portion from the data TS packet and sends it to the cache control unit 34. Further, the sequence information separating unit 32 or the sequence information analyzing unit 33 determines whether or not the data TS packet contains an error based on the transport error indicator in the packet header of the data TS packet, and the result is obtained. The cache control unit 34 can be notified. Alternatively, the arrangement information separation unit 32 can determine whether or not an error is included in the data TS packet, and if the error is included in the data TS packet, this can be discarded. With this configuration, the cache control unit 34 can save only the payload portion of the data TS packet in the RAM 36, thereby reducing the required capacity of the RAM 36.

[Modification 7]
In the deletion packet selection unit 35 in the data receiving apparatus according to the first embodiment of the present invention, the module having the smallest module packet size is selected as the module to be deleted. However, the present invention is not limited to this. . The deletion packet selection unit 35 may be configured to select a module having the largest module packet size as a module to be deleted. Since the small size module has a higher probability that all data TS packets are aligned than the large size module, it is easy to secure a free space in the RAM 36, and the RAM 36 can be used more efficiently.

[Modification 8]
The deletion packet selection unit 35 in the data receiving apparatus according to the first embodiment of the present invention is configured to select a module to be deleted on the basis of the module packet size, that is, the number of TS packets included in the module. However, the present invention is not limited to this. Even when the number of TS packets included in the module is not included in the array information, the module having the maximum or minimum data amount of the module can be selected as the module to be deleted.

[Modification 9]
In the deletion packet selection unit 35 in the data receiving apparatus according to the first embodiment of the present invention, the module having the longest module retransmission cycle is selected as the module to be deleted. However, the present invention is not limited to this. . The deletion packet selection unit 35 may be configured to select a module having the shortest module retransmission cycle as a deletion target module. In the case shown in FIG. 7, the retransmission cycle of module # 0 is 10, the retransmission cycle of module # 1 is 20, and the retransmission cycle of module # 2 is 30. Therefore, the deletion packet selection unit 35 selects module # 0 having the shortest module retransmission cycle as a module to be deleted.

  A module having a short retransmission cycle has a higher number of times of receiving the same data TS packet within a certain period than a module having a long retransmission cycle, and is highly likely to have the data TS packet. Therefore, by preferentially storing modules with a long retransmission cycle that are unlikely to have data TS packets within a certain period, it is possible to prevent a situation where data TS packets of modules with a long retransmission cycle are not aligned for a long period of time. Can do.

[Modification 10]
As described above, the arrangement information only needs to include at least one or a plurality of pieces of information necessary for specifying a TS packet, and not all information needs to be included in the arrangement information. . The minimum information that needs to be included in the array information differs depending on what the deletion packet selection unit 35 uses as a determination criterion when selecting a deletion target packet.

  When the deletion packet selection unit 35 uses the module packet size as a determination criterion, the minimum information that needs to be included in the array information is the number of TS packets included in the module.

  However, as described above, when the number of TS packets included in the module is not included in the array information, the deletion packet selector 35 determines the number of the last data TS packet in the DSM-CC section to which the data TS packet belongs. The module packet size is estimated using the number of the last DSM-CC section constituting the module to which the data TS packet belongs. In such a case, the minimum information that needs to be included in the array information constitutes the number of the last data TS packet in the DSM-CC section to which the data TS packet belongs and the module to which the data TS packet belongs. This is the number of the last DSM-CC section.

  Further, in the case described in the modification example 8, the minimum information that needs to be included in the array information is the data amount of the module.

  When the deletion packet selection unit 35 uses the module fill rate as a criterion, the minimum information that needs to be included in the array information is the number of the module to which the TS packet belongs and the TS packet included in the module. Is the number of The number of data TS packets corresponding to a specific module among the normally received data TS packets is determined by, for example, the data TS packet in the attribute information of each normally received data TS packet in module # 0. Can be obtained by counting the number of modules to which the module number belongs to 0.

  However, as described above, when the number of TS packets included in the module is not included in the array information, the deletion packet selector 35 determines the number of the last data TS packet in the DSM-CC section to which the data TS packet belongs. The module packet size is estimated using the number of the last DSM-CC section constituting the module to which the data TS packet belongs. In such a case, the minimum information that needs to be included in the array information includes the number of the module to which the data TS packet belongs, the number of the last data TS packet in the DSM-CC section to which the data TS packet belongs, and This is the number of the last DSM-CC section constituting the module to which the data TS packet belongs.

  When the deletion packet selection unit 35 selects a DSM-CC section in which the data TS packet # 0 has not been received as a deletion target, the minimum information that needs to be included in the array information is that the TS packet is It is the number of the DSM-CC section to which it belongs and the number of the TS packet in the DSM-CC section to which the TS packet belongs.

  When the deletion packet selection unit 35 uses the module retransmission cycle as a criterion, the minimum information that needs to be included in the array information is the module retransmission cycle.

  When the deletion packet selection unit 35 uses the priority reception module designation as a determination criterion, the minimum information that needs to be included in the array information is the number of the module to which the TS packet belongs. In this case, the component number is required in addition to the information included in the array information.

  When the deletion packet selection unit 35 uses the DSM-CC section fullness as a criterion, the minimum information that needs to be included in the array information is the number of the DSM-CC section to which the TS packet belongs and This is the number of the last TS packet in the DSM-CC section to which the TS packet belongs. The number of data TS packets corresponding to a specific DSM-CC section among the normally received data TS packets is, for example, attribute information of each normally received data TS packet in DSM-CC section # 0. It can be obtained by counting how many of the DSM-CC section number to which the TS packet belongs is 0.

  The embodiment disclosed this time 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.

It is a functional block diagram of the data receiver which concerns on 1st Embodiment. It is a functional block diagram of TS decoding processing part 3 concerning a 1st embodiment. It is a functional block diagram of the carousel reception processing unit 22 according to the first embodiment. 3 is a flowchart that defines an operation procedure of each functional block in a carousel reception processing unit 22. It is a figure which shows an example of each module which comprises a component. It is a figure which shows the transmission order of a DSM-CC section. It is a figure which shows the reception result of a data TS packet. It is a figure which shows an example of each module which comprises a component. It is a figure which shows the transmission order of a DSM-CC section. It is a figure which shows the reception result of a data TS packet. It is a figure which shows the data structure used with a DSM-CC data carousel transmission system. It is a conceptual diagram of the data transmission performed by a DSM-CC data carousel transmission system. It is a figure which shows the detailed structure of TS packet.

Explanation of symbols

  1 tuner, 2 demodulator, 3 TS decode processor, 4 audio decode processor, 5 video decode processor, 6 presentation processor, 7 browser request processor, 8 browser, 9 RAM, 10 CPU, 21 PID filter unit, 22 Carousel reception processing unit, 31 Carousel identification unit, 32 Sequence information separation unit, 33 Sequence information analysis unit, 34 Cache control unit, 35 Delete packet selection unit, 36 RAM, 37 Data reconstruction unit, 38 RAM

Claims (45)

A receiver that divides content into a plurality of packets, includes the divided packets, receives transmission data that is repeatedly transmitted, extracts one or more packets from the transmission data, and outputs them;
A first memory for temporary storage;
Upon receiving the packet, it is determined whether or not the packet is normally received. When the packet is normally received, at least one of the packets belonging to the group to which the normally received packet belongs is not normally received. A cache control unit for storing the normally received packet in the first memory;
A deletion packet selector for selecting a packet to be deleted;
The cache control unit outputs a deletion target selection command if the free space of the first memory is insufficient when the normally received packet is stored in the first memory,
The deletion packet selection unit receives the deletion target selection command, and selects a predetermined packet from one or a plurality of packets stored in the first memory and a reception completion packet that is the normally received packet. Selecting one or a plurality of packets according to a condition, and outputting deletion target packet information indicating the packet to be deleted to the cache control unit;
The cache control unit is a data receiving device that deletes a packet based on the deletion target packet information. The content is divided into one or more modules, the module is divided into one or more sections, the section is divided into one or more packets,
The transmission data is composed of the one or a plurality of packets,
The packet includes packet specifying information for specifying the packet,
The group is the section;
When the cache control unit normally receives the packet, if at least one of the packets of the section to which the normally received packet belongs is not normally received, the cache control unit transmits the normally received packet to the first memory. Save to
When the cache control unit saves the normally received packet in the first memory, if the free space of the first memory is insufficient, the packet is included in the reception completion packet. Output specific information as the deletion target selection command,
2. The data receiving apparatus according to claim 1, wherein the deletion packet selection unit selects one or a plurality of packets from the reception completion packet according to a predetermined condition based on the packet specifying information. The packet specifying information is the number of packets included in the module to which the reception completion packet belongs,
The cache control unit outputs the packet identification information when the first memory has insufficient free space,
3. The data receiving apparatus according to claim 2, wherein the deletion packet selection unit selects a packet belonging to a module having the maximum or minimum number of packets based on the packet specifying information. The packet identification information is the number of the module to which the reception completion packet belongs and the number of packets included in the module to which the reception completion packet belongs,
The cache control unit outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection unit calculates the packet sufficiency rate of the module from the number of packets included in the module and the number of packets corresponding to the module among the reception completion packets based on the packet identification information. The data receiving apparatus according to claim 2, wherein a packet belonging to a module having the smallest packet filling rate is selected. The packet specifying information includes a section number to which the reception completion packet belongs and a number of the reception completion packet in the section,
The cache control unit outputs the packet identification information when the first memory has insufficient free space,
3. The data receiving apparatus according to claim 2, wherein the deletion packet selection unit selects a packet belonging to a section in which the first packet is not normally received from sections to which the reception completion packet belongs, based on the packet specifying information. . The packet specifying information is a retransmission cycle of the module to which the reception completion packet belongs,
The cache control unit outputs the packet identification information when the first memory has insufficient free space,
3. The data receiving apparatus according to claim 2, wherein the deletion packet selection unit selects a packet belonging to a module having the maximum or minimum retransmission period based on the packet identification information. The packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the reception completion packet, respectively. The number of sections in the module,
The cache control unit outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection unit is configured to determine, based on the packet identification information, the number of packets included in one or a plurality of sections belonging to a module and the sections included in the module among sections to which the reception completion packet belongs. The data receiving apparatus according to claim 2, wherein the number of packets included in the module is calculated from the number of packets, and packets belonging to the module having the maximum or minimum calculated number of packets are selected. The packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the reception completion packet, respectively. The number of sections in the module,
The cache control unit outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection unit is configured to determine, based on the packet identification information, the number of packets included in one or a plurality of sections belonging to a module and the sections included in the module among sections to which the reception completion packet belongs. The number of packets included in the module is calculated from the number of packets, and the packet sufficiency rate of the module is calculated from the calculated number of packets and the number of packets corresponding to the module among the reception completion packets. 3. The data receiving apparatus according to claim 2, wherein a packet belonging to a module having the smallest packet filling rate is selected. The packet specifying information is a data amount of a module to which the reception completion packet belongs,
The cache control unit outputs the packet identification information when the first memory has insufficient free space,
The data receiving apparatus according to claim 2, wherein the deletion packet selection unit selects a packet belonging to a module having the maximum or minimum data amount based on the packet specifying information. The content is divided into one or more modules, the module is divided into one or more sections, the section is divided into one or more packets,
The transmission data is composed of the one or a plurality of packets,
The packet includes packet specifying information for specifying the packet,
The group is the section;
When the cache control unit normally receives all the packets of the section to which the normally received packet belongs when the packet is normally received, the cache control unit generates and outputs the section and is stored in the first memory. Delete all packets that correspond to the section
A second memory for temporary storage;
When a section is received from the cache control unit, and at least one of the sections constituting the module is not received, a packet included in the section received from the cache control unit is transmitted to the second memory. When all the sections constituting the module are received, the module is generated and output, and all the packets corresponding to the module are deleted from the packets stored in the second memory. A data reconstruction unit to perform,
A browser requesting a module containing the specified browsing data;
Based on the module requested from the browser, a module for generating a priority reception module indicating a module to be received preferentially is generated and output, and the module requested from the browser among the modules received from the data reconstruction unit And a browser request processing unit for outputting
The browser receives a module from the browser request processing unit, extracts the designated browsing data from the module, performs a layout, and outputs the layout browsing data,
When the cache control unit normally receives the packet, if at least one of the packets of the section to which the normally received packet belongs is not normally received, the cache control unit transmits the normally received packet to the first memory. Save to
When the cache control unit saves the normally received packet in the first memory, if the free space of the first memory is insufficient, the packet is included in the reception completion packet. Output specific information as the deletion target selection command,
2. The data reception according to claim 1, wherein the deletion packet selection unit selects one or a plurality of packets according to a predetermined condition from the reception completion packets based on the packet identification information and the priority reception module designation. apparatus. The packet specifying information is a module number to which each of the reception completion packets belongs,
The cache control unit outputs the packet identification information when the first memory has insufficient free space,
The browser request processing unit outputs a priority reception module designation indicating a module including a startup document that is browsing data to be presented immediately after the browser is started,
The data according to claim 10, wherein the deletion packet selection unit preferentially selects a packet belonging to a module other than the module indicated by the priority reception module designation as a deletion target based on the packet identification information and the priority reception module designation. Receiver device. The packet specifying information is a module number to which each of the reception completion packets belongs,
The cache control unit outputs the packet identification information when the first memory has insufficient free space,
The browser request processing unit outputs a priority reception module designation indicating a module including the designated browsing data,
The data according to claim 10, wherein the deletion packet selection unit preferentially selects a packet belonging to a module other than the module indicated by the priority reception module designation as a deletion target based on the packet identification information and the priority reception module designation. Receiver device. The content is divided into one or more components, the components are divided into one or more modules,
Based on a packet identifier included in the header of the packet received from the receiving unit, the number of the component to which the packet belongs is obtained, and further includes a carousel identifying unit that outputs to the cache control unit,
When the cache control unit stores the normally received packet in the first memory, if the free space of the first memory is insufficient, the cache control unit sets the number of the component to which the reception completion packet belongs. Output further to the delete packet selector,
The packet specifying information is a module number to which each of the reception completion packets belongs,
The browser request processing unit outputs a priority reception module designation indicating a module included in a component to which the module including the designated browsing data belongs,
The deletion packet selection unit preferentially deletes a packet included in a module belonging to a component other than the component indicated by the priority reception module designation based on the packet identification information, the component number, and the priority reception module designation. The data receiving device according to claim 10, which is selected as: The packet identification information further includes a section number to which the reception completion packet belongs and a number of packets included in the section to which the reception completion packet belongs,
The cache control unit outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection unit is configured to determine the section based on the number of packets included in the section belonging to the selected module and the number of packets corresponding to the section of the reception completion packets based on the packet identification information. The claim 3, the claim 4, the claim 9, the claim 11, the claim 13 or the claim 13, wherein a packet belonging to a section having the smallest packet filling rate is selected. The data receiving device described. The cache control unit outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection unit is configured to determine the section based on the number of packets included in the section belonging to the selected module and the number of packets corresponding to the section of the reception completion packets based on the packet identification information. The data reception device according to claim 7 or 8, wherein a packet filling rate is calculated and a packet belonging to a section having the smallest packet filling rate is selected. A data receiving method in a data receiving device including a first memory,
Receiving step of dividing the content into a plurality of packets, receiving the transmission data repeatedly transmitted including the divided packets, extracting one or a plurality of packets from the transmission data, and outputting;
Upon receiving the packet, it is determined whether or not the packet is normally received. When the packet is normally received, at least one of the packets belonging to the group to which the normally received packet belongs is not normally received. A cache control step for storing the normally received packet in the first memory;
A deletion packet selection step of selecting a packet to be deleted,
In the cache control step, when the normally received packet is stored in the first memory, if the free space of the first memory is insufficient, a deletion target selection instruction is output,
The deletion packet selection step receives a deletion target selection command, and selects a predetermined packet from one or more packets stored in the first memory and a reception completion packet that is the normally received packet. Select one or more packets according to the conditions, and output deletion target packet information indicating the packet to be deleted,
A data receiving method in which the cache control step deletes a packet based on the deletion target packet information. The content is divided into one or more modules, the module is divided into one or more sections, the section is divided into one or more packets,
The transmission data is composed of the one or a plurality of packets,
The packet includes packet specifying information for specifying the packet,
The group is the section;
In the cache control step, when the packet is normally received, if at least one of the packets of the section to which the normally received packet belongs is not normally received, the normally received packet is transferred to the first memory. Save to
In the cache control step, when the normally received packet is stored in the first memory, if the free space of the first memory is insufficient, the packet included in the reception completion packet Output specific information as the deletion target selection command,
17. The data reception method according to claim 16, wherein the deletion packet selection step selects one or a plurality of packets according to a predetermined condition from the reception completion packets based on the packet identification information. The packet specifying information is the number of packets included in the module to which the reception completion packet belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
18. The data reception method according to claim 17, wherein the deletion packet selection step selects a packet belonging to a module having the maximum or minimum number of packets based on the packet specifying information. The packet identification information is the number of the module to which the reception completion packet belongs and the number of packets included in the module to which the reception completion packet belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection step calculates the packet sufficiency rate of the module from the number of packets included in the module and the number of packets corresponding to the module among the reception completion packets based on the packet identification information. The data receiving method according to claim 17, wherein a packet belonging to a module having the smallest packet fullness rate is selected. The packet specifying information includes a section number to which the reception completion packet belongs and a number of the reception completion packet in the section,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
18. The data reception method according to claim 17, wherein the deletion packet selection step selects a packet belonging to a section in which the first packet is not normally received from sections to which the reception completion packet belongs, based on the packet specifying information. . The packet specifying information is a retransmission cycle of the module to which the reception completion packet belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
18. The data reception method according to claim 17, wherein the deletion packet selection step selects a packet belonging to a module having the maximum or minimum retransmission period based on the packet identification information. The packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the reception completion packet, respectively. The number of sections in the module,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
In the deletion packet selection step, the number of packets included in one or a plurality of sections belonging to a certain module and the sections included in the module among the sections to which the reception completion packet belongs, based on the packet specifying information. The data reception method according to claim 17, wherein the number of packets included in the module is calculated from the number of packets, and packets belonging to the module having the maximum or minimum calculated number of packets are selected. The packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the reception completion packet, respectively. The number of sections in the module,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
In the deletion packet selection step, the number of packets included in one or a plurality of sections belonging to a certain module and the sections included in the module among the sections to which the reception completion packet belongs, based on the packet specifying information. The number of packets included in the module is calculated from the number of packets, and the packet sufficiency rate of the module is calculated from the calculated number of packets and the number of packets corresponding to the module among the reception completion packets. 18. The data receiving method according to claim 17, wherein a packet belonging to a module having the smallest packet filling rate is selected. The packet specifying information is a data amount of a module to which the reception completion packet belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
18. The data reception method according to claim 17, wherein the deletion packet selection step selects a packet belonging to a module having the maximum or minimum data amount based on the packet specifying information. The data receiving device further includes a second memory,
The content is divided into one or more modules, the module is divided into one or more sections, the section is divided into one or more packets,
The transmission data is composed of the one or a plurality of packets,
The packet includes packet specifying information for specifying the packet,
The group is the section;
The cache control step generates and outputs the section when all packets of the section to which the normally received packet belongs are normally received when the packet is normally received, and is stored in the first memory. Delete all packets that correspond to the section
In the data receiving method, when the section output in the cache control step is received and at least one section among the sections constituting the module is not received, the section output in the cache control step Are stored in the second memory, and when all the sections constituting the module are received, the module is generated and output, and among the packets stored in the second memory, A data reconstruction step of deleting all packets corresponding to the module;
A browser step for requesting a module containing the specified browsing data;
Based on the module requested in the browser step, generates and outputs a priority reception module designation indicating a module to be preferentially received, and among the modules output in the data reconfiguration step, in the browser control step A browser request processing step for outputting the requested module;
The browser step receives the module output in the browser request processing step, performs the layout by extracting the designated browsing data from the module, and outputs the layout browsing data;
In the cache control step, when the packet is normally received, if at least one of the packets of the section to which the normally received packet belongs is not normally received, the normally received packet is transferred to the first memory. Save to
In the cache control step, when the normally received packet is stored in the first memory, if the free space of the first memory is insufficient, the packet included in the reception completion packet Output specific information as the deletion target selection command,
17. The data reception according to claim 16, wherein the deletion packet selection step selects one or a plurality of packets according to a predetermined condition from the reception completion packets based on the packet specifying information and the priority reception module designation. Method. The packet specifying information is a module number to which each of the reception completion packets belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
The browser request processing step outputs a priority reception module designation indicating a module including a startup document that is browsing data to be presented immediately after the start of the browser control step,
26. The data according to claim 25, wherein the deletion packet selection step preferentially selects a packet belonging to a module other than the module indicated by the priority reception module designation as a deletion target based on the packet identification information and the priority reception module designation. Reception method. The packet specifying information is a module number to which each of the reception completion packets belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
The browser request processing step outputs a priority reception module designation indicating a module including the designated browsing data;
26. The data according to claim 25, wherein the deletion packet selection step preferentially selects a packet belonging to a module other than the module indicated by the priority reception module designation as a deletion target based on the packet identification information and the priority reception module designation. Reception method. The content is divided into one or more components, the components are divided into one or more modules,
The data receiving method further includes a carousel identifying step of acquiring and outputting a number of a component to which the packet belongs based on a packet identifier included in a header of the packet output in the receiving step,
In the cache control step, when the normally received packet is stored in the first memory, if the free space of the first memory is insufficient, the number of the component to which the reception completion packet belongs is further added. Output,
The packet specifying information is a module number to which each of the reception completion packets belongs,
The browser request processing step outputs a priority reception module designation indicating a module included in a component to which the module including the designated browsing data belongs,
The deletion packet selection step preferentially deletes a packet included in a module belonging to a component other than the component indicated by the priority reception module designation based on the packet identification information, the component number, and the priority reception module designation. The data receiving method according to claim 25, wherein the data receiving method is selected as: The packet identification information further includes a section number to which the reception completion packet belongs and a number of packets included in the section to which the reception completion packet belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection step is configured to determine, based on the packet identification information, from the number of packets included in the section belonging to the selected module and the number of packets corresponding to the section of the reception completion packets. The packet filling rate is calculated, and the packet belonging to the section having the smallest packet filling rate is selected, the claim 18, the claim 21, the claim 24, the claim 26, the claim 27, or the claim 28. The data receiving method described. The cache control step outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection step is configured to determine, based on the packet identification information, from the number of packets included in the section belonging to the selected module and the number of packets corresponding to the section of the reception completion packets. 24. The data receiving method according to claim 22 or 23, wherein a packet filling rate is calculated and a packet belonging to a section having the smallest packet filling rate is selected. A data reception program in a data reception apparatus including a first memory, the computer comprising:
Receiving step of dividing the content into a plurality of packets, receiving the transmission data repeatedly transmitted including the divided packets, extracting one or a plurality of packets from the transmission data, and outputting;
A first memory for temporary storage;
Upon receiving the packet, it is determined whether or not the packet is normally received. When the packet is normally received, at least one of the packets belonging to the group to which the normally received packet belongs is not normally received. A cache control step for storing the normally received packet in the first memory;
A deletion packet selection step for selecting a packet to be deleted, and
In the cache control step, when the normally received packet is stored in the first memory, if the free space of the first memory is insufficient, a deletion target selection instruction is output,
The deletion packet selection step receives a deletion target selection command, and selects a predetermined packet from one or more packets stored in the first memory and a reception completion packet that is the normally received packet. Select one or more packets according to the conditions, and output deletion target packet information indicating the packet to be deleted,
The cache control step is a data receiving program for deleting a packet based on the deletion target packet information. The content is divided into one or more modules, the module is divided into one or more sections, the section is divided into one or more packets,
The transmission data is composed of the one or a plurality of packets,
The packet includes packet specifying information for specifying the packet,
The group is the section;
In the cache control step, when the packet is normally received, if at least one of the packets of the section to which the normally received packet belongs is not normally received, the normally received packet is transferred to the first memory. Save to
In the cache control step, when the normally received packet is stored in the first memory, if the free space of the first memory is insufficient, the packet included in the reception completion packet Output specific information as the deletion target selection command,
32. The data reception program according to claim 31, wherein the deletion packet selection step selects one or a plurality of packets according to a predetermined condition from the reception completion packets based on the packet identification information. The packet specifying information is the number of packets included in the module to which the reception completion packet belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
33. The data reception program according to claim 32, wherein the deletion packet selection step selects a packet belonging to a module having the maximum or minimum number of packets based on the packet specifying information. The packet identification information is the number of the module to which the reception completion packet belongs and the number of packets included in the module to which the reception completion packet belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection step calculates the packet sufficiency rate of the module from the number of packets included in the module and the number of packets corresponding to the module among the reception completion packets based on the packet identification information. 33. The data reception program according to claim 32, wherein a packet belonging to a module having the smallest packet filling rate is selected. The packet specifying information includes a section number to which the reception completion packet belongs and a number of the reception completion packet in the section,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
33. The data reception program according to claim 32, wherein the deletion packet selection step selects, based on the packet identification information, a packet belonging to a section in which the first packet is not normally received among sections to which the reception completion packet belongs. . The packet specifying information is a retransmission cycle of the module to which the reception completion packet belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
33. The data reception program according to claim 32, wherein the deletion packet selection step selects a packet belonging to a module having the maximum or minimum retransmission cycle based on the packet identification information. The packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the reception completion packet, respectively. The number of sections in the module,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
In the deletion packet selection step, the number of packets included in one or a plurality of sections belonging to a certain module and the sections included in the module among the sections to which the reception completion packet belongs, based on the packet specifying information. 33. The data receiving program according to claim 32, wherein the number of packets included in the module is calculated from the number of packets, and packets belonging to the module having the maximum or minimum calculated number of packets are selected. The packet identification information includes the module number to which the reception completion packet belongs, the section number to which the reception completion packet belongs, the number of packets included in the section to which the reception completion packet belongs, and the reception completion packet, respectively. The number of sections in the module,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
In the deletion packet selection step, the number of packets included in one or a plurality of sections belonging to a certain module and the sections included in the module among the sections to which the reception completion packet belongs, based on the packet specifying information. The number of packets included in the module is calculated from the number of packets, and the packet sufficiency rate of the module is calculated from the calculated number of packets and the number of packets corresponding to the module among the reception completion packets. 33. The data reception program according to claim 32, wherein a packet belonging to a module having the smallest packet filling rate is selected. The packet specifying information is a data amount of a module to which the reception completion packet belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
33. The data reception program according to claim 32, wherein the deletion packet selection step selects a packet belonging to a module having the maximum or minimum data amount based on the packet specifying information. The data receiving device further includes a second memory,
The content is divided into one or more modules, the module is divided into one or more sections, the section is divided into one or more packets,
The transmission data is composed of the one or a plurality of packets,
The packet includes packet specifying information for specifying the packet,
The group is the section;
The cache control step generates and outputs the section when all packets of the section to which the normally received packet belongs are normally received when the packet is normally received, and is stored in the first memory. Delete all packets corresponding to the section
The data receiving program is further stored in a computer.
When the section output in the cache control step is received and at least one of the sections constituting the module is not received, the packet included in the section output in the cache control step is When all the sections constituting the module are received in the second memory, the module is generated and output, and all the packets corresponding to the module among the packets stored in the second memory are output. A data reconstruction step to delete the packets of
A browser step for requesting a module containing the specified browsing data;
Based on the module requested in the browser control step, generates and outputs a priority reception module designation indicating a module to be preferentially received, and among the modules output in the data reconfiguration step, the browser control step A browser request processing step for outputting the requested module in
The browser step receives the module output in the browser request processing step, performs the layout by extracting the designated browsing data from the module, and outputs the layout browsing data;
In the cache control step, when the packet is normally received, if at least one of the packets of the section to which the normally received packet belongs is not normally received, the normally received packet is transferred to the first memory. Save to
In the cache control step, when the normally received packet is stored in the first memory, if the free space of the first memory is insufficient, the packet included in the reception completion packet Output specific information as the deletion target selection command,
32. The data reception according to claim 31, wherein the deletion packet selection step selects one or a plurality of packets according to a predetermined condition from the reception completion packets based on the packet specification information and the priority reception module designation. program. The packet specifying information is a module number to which each of the reception completion packets belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
The browser request processing step outputs a priority reception module designation indicating a module including a startup document that is browsing data to be presented immediately after the start of the browser control step,
41. The data according to claim 40, wherein said deletion packet selection step preferentially selects a packet belonging to a module other than the module indicated by said priority reception module specification as a deletion target based on said packet specifying information and said priority reception module specification. Receiving program. The packet specifying information is a module number to which each of the reception completion packets belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
The browser request processing step outputs a priority reception module designation indicating a module including the designated browsing data;
41. The data according to claim 40, wherein said deletion packet selection step preferentially selects a packet belonging to a module other than the module indicated by said priority reception module specification as a deletion target based on said packet specifying information and said priority reception module specification. Receiving program. The content is divided into one or more components, the components are divided into one or more modules,
The data reception program further causes the computer to execute a carousel identification step of acquiring and outputting the number of the component to which the packet belongs based on the packet identifier included in the header of the packet output in the reception step,
In the cache control step, when the normally received packet is stored in the first memory, if the free space of the first memory is insufficient, the number of the component to which the reception completion packet belongs is further added. Output,
The packet specifying information is a module number to which each of the reception completion packets belongs,
The browser request processing step outputs a priority reception module designation indicating a module included in a component to which the module including the designated browsing data belongs,
The deletion packet selection step preferentially deletes a packet included in a module belonging to a component other than the component indicated by the priority reception module designation based on the packet identification information, the component number, and the priority reception module designation. 41. The data receiving program according to claim 40, which is selected as The packet identification information further includes a section number to which the reception completion packet belongs and a number of packets included in the section to which the reception completion packet belongs,
The cache control step outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection step is configured to determine, based on the packet identification information, from the number of packets included in the section belonging to the selected module and the number of packets corresponding to the section of the reception completion packets. 35, claim 34, claim 36, claim 39, claim 41, claim 43, or claim 43, wherein the packet filling rate is calculated and the packet belonging to the section with the smallest packet filling rate is selected. The data receiving program described. The cache control step outputs the packet identification information when the first memory has insufficient free space,
The deletion packet selection step is configured to determine, based on the packet identification information, from the number of packets included in the section belonging to the selected module and the number of packets corresponding to the section of the reception completion packets. 39. The data reception program according to claim 37 or claim 38, wherein a packet filling rate is calculated and a packet belonging to a section having the smallest packet filling rate is selected.

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