JP4542372B2 - Content playback device - Google Patents

Description

  The present invention relates to a content reproduction apparatus that acquires content and reproduces it according to an operation by a user. In particular, the present invention relates to a content playback apparatus that acquires and temporarily stores part or all of content data and reads and plays back the stored data when playback is started.

  With the development of information technology in recent years, various information can be acquired and used. For example, by acquiring information from a server device via the so-called Internet or the like, various contents such as video information, text information, audio information, still images, or information integrating them can be obtained from a PC (personal computer) or a mobile phone. It is possible to browse using a terminal device such as. When browsing content using a terminal device, the user first operates the terminal device to specify desired content. The terminal device acquires data by communicating with the server device in accordance with designation by the user. The terminal device reproduces the acquired data.

  However, when data is acquired via the Internet or the like, a communication process occurs in which data is exchanged between the terminal device and the server device. Can't start. For this reason, when the communication process is started after the user specifies the desired content, there is a problem that the user has to wait while performing the communication process.

  In order to solve this problem, a technique for shortening the waiting time of the user by acquiring content used by the user in advance and temporarily storing the content in the terminal device and the relay device is generally used. . In this method, part or all of the acquired and reproduced content is retained. When the content is reproduced again, the stored content data is read and reproduced. By this method, it is possible to shorten the waiting time generated by the communication process for the content acquired and reproduced in the past.

  Further, Patent Document 1 described later discloses a communication processing device in which a server device provides a temporary recording priority for each content to a receiving device, and the receiving device temporarily records content according to this priority.

  The communication processing apparatus described in Patent Literature 1 includes a transmission-side apparatus that provides content and a reception-side apparatus that receives and temporarily records the content in advance. When the receiving side device requests content, the transmitting side device calculates a temporary recording priority indicating whether the content is likely to be read out from the viewing history of the content on the receiving side device. The transmission side apparatus transmits the content and the temporary recording priority in association with each other. The receiving device temporarily records this content. When the information capacity of the content to be temporarily recorded exceeds the information capacity that can be temporarily recorded by the receiving side device, the receiving side device has the content of the same size or more of the received content whose temporary recording priority has already been temporarily recorded. Higher than the temporary recording priority is stored in place of the existing content to be compared with the temporary recording priority. According to Patent Document 1, this apparatus can preferentially record appropriate data that is highly likely to be read, and can efficiently reduce the occupation time of the communication line and the waiting time of the user. Is described.

Japanese Patent Laid-Open No. 9-326830

  In the conventional method of dealing with waiting time using content acquired in the past, content is not acquired and held for content that has never been played back in the past. Therefore, the content that is played for the first time cannot cope with the waiting time generated by the communication process.

  The transmission-side device described in Patent Literature 1 calculates a temporary recording priority based on a past content viewing history by a user. The receiving device temporarily records the content according to the temporary recording priority transmitted from the transmitting device. The content temporarily stored in the receiving side device reflects the user's past viewing history. Therefore, when there is a bias in the content to be browsed, this communication processing device may be able to appropriately reduce the waiting time. However, the user does not always browse the same content. Further, the content selection operation is not always performed after the content to be browsed is determined. It is often the case that content is selected at random or in some order, and the content to be browsed is specified after browsing a little. In such a case, it is necessary to frequently change the temporary recording priority according to the user's situation. However, in order for the receiving device described in Patent Document 1 to change the temporary recording priority, it is necessary to communicate with the transmitting device, which may cause congestion of the communication line.

  In addition, the receiving-side device described in Patent Document 1 temporarily records content provided from the server device in units of files. Since the amount of data that can be temporarily recorded is limited, a large number of contents cannot be temporarily stored when the file size of the contents is large. Further, when there are a large number of files to be temporarily recorded, the number of contents that can be temporarily recorded is limited, and contents that are highly likely to be selected by the user cannot be sufficiently recorded.

  Therefore, the present invention deals with a waiting time caused by communication processing when acquiring and playing back content, and a content playback device capable of efficiently using a large amount of various types of content without causing congestion of the communication line The purpose is to provide.

  A content reproduction apparatus according to a first aspect of the present invention is a content reproduction apparatus that acquires and reproduces a plurality of contents provided by a predetermined provider. The content reproduction apparatus includes a list preparation unit for preparing a list for determining a mutual order of a plurality of contents provided by a predetermined provider, and an acquisition unit for acquiring and holding the plurality of contents according to a predetermined acquisition order A plurality of contents acquired and held by the acquisition means and played back by the playback means in response to switching between the playback means for switching and playing the content in the order determined by the list and the content played back by the playback means Planning means for planning the acquisition order of the plurality of contents based on the relationship between the order in the list of the contents in the middle and the order in the list of the plurality of contents.

  The content reproduction apparatus plans the content acquisition order based on the mutual content order, and acquires and holds the content according to the planned acquisition order. That is, the content to be reproduced in the future is acquired and held in advance according to the order of the content to be reproduced. When reproducing, the contents acquired and held in advance are reproduced in the order of the contents. Since it is not necessary to perform communication processing at the time of starting the content, the waiting time that occurs at the start of playback can be reduced. In addition, since it is not necessary to communicate with another device in order to determine the acquisition order, the content acquisition order can be determined without causing congestion of the communication line.

  Preferably, the planning unit is responsive to the switching of the content to be played back by the playback unit, so that the playback unit obtains a plurality of differences in order from the content in the list of the content being played back in ascending order. Means for planning content acquisition order;

  The reproduction means reproduces the content in the order determined by the list. Content with a small difference in order on the list is played back in an order close to each other. For this reason, there is a high possibility that content that is being reproduced and content that has a small difference in order on the list will be reproduced by switching from the content that is being reproduced. Therefore, by acquiring the content in order from such content, it is possible to acquire in advance and reliably content that is highly likely to be reproduced. Therefore, the waiting time that occurs at the start of content playback can be reduced with high probability.

  Preferably, the planning unit specifies, for each of the plurality of contents, the minimum acquisition data to be acquired for starting the reproduction and the additional acquisition data to be acquired in addition to the minimum acquisition data for reproducing the content. In response to the switching of the content to be played back by the data specifying means and the playback means, based on the relationship between the order in the list of contents being played back by the playback means and the order in the list of multiple contents And a two-stage planning means for determining an acquisition order of the plurality of contents so that the minimum acquisition data and the additional acquisition data are acquired in different orders. The acquisition means includes two-stage acquisition means for acquiring the minimum acquisition data and additional acquisition data of a plurality of contents in different orders according to the acquisition order determined by the two-stage planning means.

  According to the plan by the two-stage planning means, the two-stage obtaining means obtains data to be acquired for starting reproduction in a different order from the order in which the entire content is obtained. Data necessary for starting reproduction can be acquired in advance as necessary. Therefore, by performing playback based on the minimum acquired data that has been acquired and held, it is possible to reduce the occurrence of waiting time caused by acquiring content at the start of playback.

  More preferably, the data specifying means adds a minimum acquisition data of the content and additional information according to the means for determining the content format for each of the plurality of contents and the content format determined by the means for determining. Means for identifying the acquired data.

  Depending on the content format, the data required to start playback may differ. In addition, there is a case where parts that are highly necessary to be acquired in advance are different. In such a case, by specifying the reproduction acquisition data and additional acquisition data according to the content format, it is possible to appropriately acquire and hold data that is highly required to be acquired for reproduction. It becomes. Since the reproduction of the content can be started with the appropriate data held, the waiting time can be reduced.

  The planning means further includes means for determining the data amount of the minimum acquired data and the data amount of the additional acquired data for each of the plurality of contents based on the content format determined by the means for determining. But you can.

  Preferably, the content reproduction apparatus further includes, for a plurality of contents, the content among the data representing the contents based on the relationship between the order in the list of contents being reproduced by the reproducing unit and the order in the list of the plurality of contents. Data amount determining means for determining the amount of data to be acquired is included. The acquisition means includes means for acquiring and holding a plurality of contents in the data amount determined by the data amount determination means in accordance with a predetermined acquisition order.

  The amount of data to be acquired is determined based on the order relationship in the list with the content being reproduced, and the content is partially acquired by the determined amount of data. As a result, it is possible to acquire and hold contents in advance for a large number of contents with a smaller amount of data than to acquire the entire contents. The content required at the start of reproduction is not necessarily all data representing the content. Therefore, it is possible to efficiently reduce the waiting time that occurs at the start of playback for more content that can be played back.

  More preferably, the data amount determining means determines the amount of data to be acquired for each of the plurality of contents so that many contents having a small difference from the order in the list of the contents being reproduced are acquired by the reproducing means. Including means.

  Content with a small difference in order on the list is likely to be played by switching from the content being played. Therefore, when the acquisition unit acquires more data representing such content, it is possible to acquire in advance and reliably content that is highly likely to be reproduced. Therefore, the waiting time that occurs at the start of content playback can be reduced with high probability.

  Means for generating and displaying information indicating the data amount determined by the data amount determining unit and the data amount acquired and held by the acquiring unit for the content being played back by the playback unit. Further, it may be included.

  Preferably, in response to a predetermined condition being satisfied, the playback unit is configured to switch content specifying unit for specifying the content to be switched and played based on the list, and the content being played back. Switching reproduction means for switching to and reproducing the content specified by the switching content identification means.

  More preferably, in response to the end of the reproduction of the content by the reproduction unit, the switching content specifying unit switches the content determined in the next order of the content that has been reproduced by the list as the content to be switched and reproduced. Means for identifying.

  Since the content to be reproduced next is specified in the order determined by the list, the content can be automatically reproduced sequentially according to the list. Further, since the reproduction is performed according to the list, the plan of the content acquired in advance is more accurate. Therefore, it is possible to reduce the waiting time that occurs when the content is switched.

  More preferably, the content reproduction apparatus further includes content selection means for selecting one of the contents ordered by the list according to an operation by the user. The switching content specifying unit includes a unit for specifying the content selected by the content selection unit as the content to be switched and reproduced.

  The content to be played can be selected and played according to the operation by the user. Furthermore, even when the user selects content, the content can be specified based on the list. Therefore, it is possible to acquire content in advance based on the list.

  More preferably, the content reproduction device further responds to the frequency measurement means for measuring the frequency of selection of the content by the content selection means, and the frequency measured by the frequency measurement means has reached a predetermined value, Means for deferring a specific start of the content by the means for specifying for a predetermined time.

  Whenever the content to be reproduced is frequently switched according to the user's operation, it is expected that the processing will not be in time if the plan acquisition unit plans the content acquisition sequence and the acquisition unit acquires and holds the content. In such a case, if communication processing is performed in conjunction with an operation by the user, there is a possibility that communication processing for the next content may occur before playback of a certain content can be started. In such a case, the means for holding off holds the specification of the content to be reproduced once. While being held, the content to be switched and played back is not specified. Every time the user performs an operation, the content acquisition order is not planned and the content is not acquired and held by the acquisition means. Therefore, congestion of the communication line is not caused.

  The list may include information defining the order of the plurality of contents and summary information indicating an outline of each of the plurality of contents. In response to the fact that the frequency measured by the frequency measuring means has reached a predetermined value, the means for holding holds the specific start of the content by the specifying means for a predetermined time, and the content selecting means Means for displaying summary information about the selected content.

  While the content identification is suspended, an overview of the selected content is displayed based on the list. Even while the specification of the content to be reproduced is suspended, the user can be informed of what the selected content is. Therefore, it is possible to support an operation for selecting a content by the user.

  More preferably, there are a plurality of lists. Each of the plurality of lists corresponds to a predetermined channel. The channels have an order relationship with each other. The list preparation means includes channel order list holding means for acquiring a plurality of lists and holding them according to the order relation of channels corresponding to the lists. The content reproduction apparatus further includes channel selection means for selecting a channel in accordance with a user operation. In response to selection of the channel by the channel selection means, the switching content specifying means specifies the content to be switched and reproduced based on the list held in the channel order list holding means corresponding to the selected channel. Including means.

  The list is acquired and held in the order of channels selected by the user. In response to an operation from the user, the means for specifying first specifies a list corresponding to the selected channel. Further, the content to be reproduced is specified based on the specified list. The identified content is reproduced by the reproducing means. Further, the content acquisition order is planned based on the order of the content being reproduced on the list. Therefore, the user does not need to specify the content individually, and it is possible to reduce the labor required for selecting the user's content.

  More preferably, the planning means includes means for determining the acquisition order based on the order in the list of contents specified by the means for specifying and the order relation of the channels corresponding to the list.

  When a channel is selected by the user's selection, for example, in an adjacent channel, the content in the order to be reproduced at that time is highly likely to be specified as the content to be reproduced by the selection according to the operation by the user. . Therefore, by planning the acquisition order based on the channel order, the waiting time can be reduced even when the content is switched by selecting the channel.

  The means for determining is, in order from the content included in the list, having a small difference in order in the list with the content being played back by the playing means, and a small difference in order relationship with the channel corresponding to the list. Proximity channel order priority acquisition planning means for determining the acquisition order so as to be acquired may be included.

  More preferably, the reproduction unit further includes a determination unit for determining whether acquisition and holding by the acquisition unit of the content specified by the switching content specifying unit is completed. The switching reproduction means switches the content to be reproduced from the content being reproduced to the content specified by the switching content identification means according to the determination result by the determination means, and the reproduction output of the content being reproduced. Selective switching reproduction means for selectively executing the operation of switching the content to be reproduced from the content being reproduced to the content identified by the switching content identification means after applying the transition effect for a predetermined time; Including.

  When the acquisition and holding of the content is not completed, a waiting time occurs when the content is switched. Since the content reproduced before switching is held by the acquisition means, the selective switching reproduction means can reproduce this content during the waiting time. Therefore, by applying the transition effect to the content before switching and reproducing, it is possible to avoid a state in which no content is output during the waiting time.

  The reproduction means further includes means for calculating a predicted value of the time required to acquire the contents to be switched and played back in response to the determination means determining that the acquisition and holding by the acquisition means have not been completed. May be included. The selective switching reproduction means switches the content to be reproduced from the content being reproduced to the content specified by the switching content identification means according to the determination result by the determination means, and the reproduction output of the content being reproduced. After applying the time transition effect indicated by the predicted value calculated by the means for calculating, selectively performing the operation of switching the content to be played back from the content being played back to the content specified by the switching content specifying means Means for doing so.

  The means for calculating predicts the time required for content acquisition, that is, the waiting time that occurs. The means for executing applies a transition effect according to the length of the waiting time when the waiting time occurs. Therefore, it is possible to predict how long the waiting time will last depending on the progress of the transition effect.

  More preferably, the list includes information that defines the order of the plurality of contents and summary information that indicates an outline of each of the plurality of contents. The reproduction means further includes means for displaying summary information about the content in response to the switching content specifying means specifying the content to be switched and displayed.

  The means for displaying displays a summary of the content when the content to be switched and reproduced is specified. The summary information is displayed regardless of whether or not a waiting time occurs when switching contents. Therefore, even if it takes time to switch the content, it is possible to notify the user of the outline of the content.

  The list may include information that defines the order of the plurality of contents and additional information regarding at least one of the plurality of contents. In response to switching of the content to be played back by the playback means, the planning means changes the relationship between the order in the list of content being played back by the playback means and the order in the list of multiple contents, and additional information. And means for planning an acquisition order of the plurality of contents.

  The additional information may include information indicating the user's preference for at least one of the plurality of contents.

  When the computer program according to the second aspect of the present invention is executed by a computer, it causes the computer to operate as any one of the content reproduction apparatuses according to the first aspect described above. As a result, the functions and effects of the content reproduction apparatus described above can be achieved.

  A recording medium according to a third aspect of the present invention is a computer-readable recording medium on which a computer program according to the second aspect is recorded. Therefore, the computer program recorded on the recording medium is read and executed by a computer, and the same operations and effects as those in the first aspect described above can be achieved.

  According to the first aspect of the present invention, the waiting time that occurs at the start of playback can be reduced. In addition, since it is not necessary to frequently communicate with other devices, the content acquisition order can be determined without causing congestion of the communication line. Furthermore, based on the content acquisition order, content that is highly likely to be reproduced can be acquired in advance and reliably. Data necessary for starting the reproduction can be acquired in advance as necessary, and the content can be reproduced based on the data. Therefore, it is possible to reduce the waiting time that occurs at the start of playback for more content.

  In addition, it is possible to acquire and retain appropriate content according to the content format. Content can be acquired and held in advance for a large number of content with a smaller amount of data than when the entire content is acquired. Therefore, it is possible to efficiently reduce the waiting time for many contents. Furthermore, it is possible to acquire in advance more content data that is likely to be reproduced based on the content acquisition order. Therefore, it is possible to efficiently reduce the waiting time with a small amount of retained data.

  In addition, content can be selected and played according to user operations. Furthermore, it is possible to specify content based on the list according to the operation by the user and acquire the content in advance. Also, congestion of the communication line can be avoided by deferring the specification of the content to be reproduced according to the frequency of selecting the content. Furthermore, even while content identification is suspended, the user can be notified of the outline of the selected content, and the user's operation can be supported. In addition, even when the content is switched in response to the user selecting a channel, the waiting time that occurs when switching the content can be reduced.

  Even when a waiting time occurs, a state in which nothing is output can be avoided by applying the transition effect to the content before switching and reproducing it. Furthermore, it is possible to allow the user to predict how long the waiting time will last. In addition, even if it takes time to switch the content, it is possible to notify the user of the outline of the content.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. In the drawings used for the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  In the present specification, information that is composed of video information, text information, audio information, still images, animations, or the like, or information obtained by integrating them, and that provides users with news, music, movies, games, advertisements, and the like. Is called “content”. In addition, content including information in which video information, character information, audio information, still images, animations, and the like are integrated is particularly referred to as “composite media”.

(overall structure)
FIG. 1 shows an overall configuration of a system including a content reproduction apparatus according to the present embodiment. Referring to FIG. 1, a system 50 according to the present embodiment includes a content server 54 that provides content via a communication network 52 such as the Internet, and a content server 54 that provides content via the communication network 52. The content list information is obtained via the content list information server 56 that provides the content list information indicating the reproduction order and the communication network 52, and is provided by the content server 54 in accordance with the order indicated by the content list information or the selection operation by the user. And a content playback device 60 that acquires and plays back content.

  The content server 54 is constituted by a single server or a plurality of server devices, and holds a plurality of contents. In response to the request transmitted by the content reproduction device 60 to acquire the content, the content server 54 transmits the content specified by the request among the held content. In addition, the content server 54 responds to a request from the content playback device 60 and, for the composite media provided to the content playback device 60, a composite media script indicating the playback timing of the content constituting the composite media in a predetermined format. Send. The composite media script will be described later with reference to FIG.

  The content list information includes the order of the content reproduction schedule by the content reproduction device 60 (hereinafter, this schedule is referred to as “reproduction schedule”) and information for specifying the content scheduled to be reproduced according to the reproduction schedule. The content list information server 56 prepares a plurality of content list scripts that describe content list information in a predetermined format. In response to the request for content list information from the content reproduction device 60, the content list information server 56 transmits a content list script to the content reproduction device 60. The content list script will be described later with reference to FIG.

  The content playback device 60 acquires a plurality of content list scripts from the content list information server 56 and generates a content list including a plurality of content list information. Each content list information constituting the content list is assigned a channel having a predetermined order relationship. The channel is an entity to be selected when the user performs a content selection operation, and the content reproduction device 60 specifies the content to be reproduced based on the content list information to which the channel selected by the user is assigned. The content reproduction device 60 acquires and reproduces the identified content from the content server 54 via the communication network 52.

  The content playback device 60 performs the following three types of processing in order to shorten the waiting time from the selection operation by the user that occurs due to communication processing or the like to the start of playback. The first type of process is a prefetch process in which content that is likely to be selected by the user in the next selection operation is acquired from the content server 54 and held in advance. The second type of process calculates the waiting time to be generated, and starts playing the selected content after changing the playback output of the currently playing content stepwise or continuously according to the waiting time. It is a transition process. The third type of processing is high-speed switching that interrupts the above-described two types of processing and displays a list of selectable contents in response to frequent selection operations by the user. In the prefetch process, the priority order of the contents to be prefetched is determined based on the order of the content reproduction schedule and the order of the contents related to the selection operation by the user. Furthermore, the minimum amount of data necessary for reproducing the content is acquired first, and the remaining portion of the data constituting the content is additionally acquired.

  FIG. 2 shows a functional configuration of the content reproduction device 60 in a block diagram form. Referring to FIG. 2, content reproduction device 60 includes a network communication unit 100 that communicates with content server 54 and content list information server 56 via communication network 52 shown in FIG. And an input unit 114 that receives a channel or content selection operation according to, and generates a corresponding input signal.

  The content reproduction device 60 further includes a channel list script storage unit 102 that stores a channel list script indicating a relationship between a user selectable channel and content list information. The channel list script will be described later with reference to FIG.

  The content playback device 60 is further connected to a channel list script analysis unit 104 that reads and analyzes the channel list script from the channel list script storage unit 102, and to the network communication unit 100 and the channel list script analysis unit 104 to analyze the channel list script. Based on the result, a content list script acquisition unit 106 that acquires a content list script from the content list information server 56 (see FIG. 1), and a content list script analysis unit 108 that analyzes the acquired content list script and generates a content list. And a content list storage unit 110 that stores the generated content list. The content list will be described later with reference to FIGS.

  The content playback device 60 further specifies the content to be played back and the content to be prefetched and the content to be played back based on the content list stored in the content list storage unit 110 according to the input signal from the input unit 114. And a content switching control unit 116 that performs output for displaying an outline of the content, and pre-read information for performing content reproduction output and content pre-reading processing according to control by the content switching control unit 116. Content reproduction unit 120. The content reproduction device 60 further includes a timer 118 that generates a notification signal at a timing set by the content switching control unit 116 and the content reproduction unit 120. Details of the content reproduction unit 120 will be described later with reference to FIG. Further, the prefetch information will be described later with reference to FIG.

  The content reproduction device 60 further receives prefetch information from the content reproduction unit 120, determines the order of the content to be prefetched and the amount of data to be acquired in advance for the content to be prefetched, and schedules the prefetch processing. (Hereinafter referred to as “prefetch schedule”) for prefetch planning section 122, prefetch information, information necessary for prefetch planning section 122 to plan, prefetch schedule, and prefetch processing according to prefetch schedule And a prefetch plan storage unit 124 that stores necessary information. The content reproduction device 60 is further connected to the network communication unit 100 and the prefetch plan storage unit 124, and the content prefetch unit 126 that obtains content from the content server 54 (see FIG. 1) according to the prefetch schedule and the content prefetch unit 126 obtain A content storage unit 128 for storing content.

  The content playback unit 120 has a function of reading and playing back the content stored in the content storage unit 128 according to control by the content switching control unit 116. Further, the content reproduction unit 120 refers to the information stored in the prefetch plan storage unit 124 via the prefetch plan unit 122 and determines the status of the content prefetch process based on the information stored in the prefetch plan storage unit 124. And pre-read information is generated as necessary and provided to the pre-read plan unit 122.

  FIG. 3 shows a detailed configuration of the content reproduction unit 120. Referring to FIG. 3, content reproduction unit 120 reads and reproduces content to be reproduced or prefetched from content storage unit 128 according to control by content switching control unit 116 shown in FIG. It includes a reproduction component group 140 that determines and generates prefetch information. The content playback unit 120 is further connected to the network communication unit 100 shown in FIG. 2, and a composite media script acquisition unit 142 that acquires a composite media script from the content server 54 (see FIG. 1), and analyzes the composite media script. It includes a composite media script analysis unit 144 that generates a composite media playback schedule that defines the playback timing of content constituting the media, and a composite media playback schedule storage unit 146 that stores the generated composite media playback schedule. The content playback unit 120 further issues a composite media script acquisition command to the composite media script acquisition unit 142 and the composite media playback schedule stored in the composite media playback schedule storage unit 146 for the composite media to be played back or prefetched. , A composite media playback control unit 148 for controlling the playback component group 140, generating prefetch information, and exchanging prefetch information with the prefetch planning unit 122 is included.

  The reproduction component group 140 is an animation reproduction unit 150A that performs reading and reproduction output of content, generation of prefetch information, and exchange of prefetch information in accordance with the types of content to be reproduced such as animation, character strings, still images, and moving images. In addition, individual playback units such as a text playback unit 150B, a still image playback unit 150C, and a video playback unit 150D are included. The composite media playback control unit 148 has a function of determining the type of content based on the composite media playback schedule and performing control for operating an appropriate playback unit corresponding to the type.

  FIG. 4 shows an arrangement of input buttons of a remote controller (hereinafter referred to as “remote controller”) that constitutes a part of the input unit 114 shown in FIG. Referring to FIG. 4, remote control 160 includes a power button 162 for switching on / off the power of content reproduction device 60 and a volume button 164 for adjusting the reproduction volume of the content. The remote control 160 further includes a channel selection button 166 for switching channels in a predetermined order, a return button 168 for selecting content that was scheduled to be played back in the same time period on the same channel, and one step behind. A skip button 172 for selecting content scheduled to be played back during the time period, and a play button 170 for instructing to interrupt and resume playback of the content currently being played back. The remote controller 160 further includes a plurality of numeric buttons 174 from “0” to “12”.

  FIG. 5 schematically shows a relationship among services, content list information, and channels in the present embodiment. Referring to FIG. 5, there are various services 180 such as an Internet content service 184A that provides content via the Internet, a broadcast service 184B that provides broadcast program content, and a mail service 184C that mediates transmission and reception of electronic mail. There is a form. For example, the content server 54 shown in FIG. 1 provides content via the Internet, and the service belongs to the Internet content service 184A.

  On the other hand, the channel 182 becomes an entity to be selected when the user selects content provided in various services. In the example shown in FIG. 5, for these services 184A, 184B, and 184C, there are a plurality of types of channels 186A and 186B, 188A and 188B, and 190A and 190B, respectively. For example, the content list information server 56 shown in FIG. 1 provides content list information corresponding to one channel (for example, the content list information server A channel 186A). When the user selects the content list information server A channel 186A, the content reproduction device 60 reproduces a predetermined one of the contents provided in the Internet content service 184A based on the content list information corresponding to the channel 186A. When the user selects the content list information of the content list information server B channel 186B provided by another content list information server, the content reproduction device 60 reproduces another content provided by the Internet content service 184A.

  FIG. 6 shows an example of the channel list script stored in the channel list script storage unit 102 shown in FIG. Referring to FIG. 6, channel list script 200 has a text file format and an XML (extensible Markup Language) format that is one format of a markup language. In XML, an item of information is indicated by “tag” between “<” and “>” or an item name of information. The information content of the item indicated by the tag is the tag in which the information item name is described between “<” and “>”, and the information item name is described between “</” and “>” It is described between tags. In addition, the information content of each item can be described between “<” and “/>” together with the item name. Also, multiple items can be structured by nesting tags.

  The first line is a line for declaring that the channel list script 200 is information described in the XML format. “Encoding =“ Shift_JIS ”” indicates that the character code is based on shift JIS. Information described from the tag “<csd>” on the second line to the tag “</ csd>” on the 14th line is the content of the channel list script 200.

  Additional header information is described between the tag “<head>” on the third line and the tag “</ head>” on the sixth line. The item “title” on the fourth line indicates the title of the channel list script 200. The item “author” on the fifth line indicates the creator of the channel list script 200.

  Information for each channel that can be selected by the user is described between the tag “<channeldesc>” on the seventh line and the tag “</ channeldesc>” on the thirteenth line. Each item “channel” described in the 8th to 12th lines indicates an individual channel. “Call”, “type”, and “src” described in this item are the channel number for identifying the channel indicated by this tag, the type of service provided by this channel, and the service corresponding to this channel, respectively. Is the name of a parameter indicating an identifier for identifying Further, the portions surrounded by ““ ”and“ ”” corresponding to the names of these parameters respectively indicate the parameter values.

  For example, the channel indicated by the item in the eighth row is that the channel number is “106”, the type of service provided by this channel is “NetContents”, that is, the Internet content service 184A (see FIG. 5), and this This indicates that the service identifier corresponding to the channel is URL (Uniform Resource Locator) “http: //chp-106.psd”.

  The item “channel” may further describe the correspondence with the remote controller 160 shown in FIG. For example, the parameter “directkey” in the tag on the 10th line indicates the correspondence between this channel “111” and the numeric buttons 174 of the remote controller 160. In this example, the operation to the number button “1” by the user is a selection operation of the channel “111”. The item “channel” may further describe the user's preference for the channel indicated by this tag. For example, “preferred =“ yes ”” in the tag on the 12th line indicates that this channel “117” is a favorite channel for the user.

  FIG. 7 shows an example of a content list script provided by the content list information server 56 (see FIG. 1). Referring to FIG. 7, content list script 210 has a text file format and an XML format. The first line is a line for declaring that the information is described in the XML format. Information described from the tag “<psd>” on the second line to the tag “</ psd>” on the 28th line is the content of the content list script 210. The parameter “version” in the tag on the second line indicates the version of the content list script 210. The item “channel” on the third line indicates the name of the channel to which the content list script 210 corresponds. The item “author” on the fourth line indicates the creator of the content list script 210.

  A reproduction schedule for one day is described between the tag “<day>” on the sixth line and the tag “</ day>” on the 27th line. The parameter “value” in the tag on the sixth line indicates the date on which the content reproduction according to the reproduction schedule indicated by this item is executed.

  The tag “<program>” on the 7th line and the 17th line has information about one content scheduled to be reproduced in this channel until the tag “</ program>” on the 16th line and the 26th line, respectively. Are described respectively. The information related to one content includes information indicating a time zone in which the content is scheduled to be reproduced and additional information related to the content.

  Between the tag “<schedule>” on the eighth line and the tag “</ schedule>” on the eleventh line, a time zone in which this content is scheduled to be reproduced is described. The item “starttime” on the ninth line indicates the scheduled reproduction start time of the content. In this example, 0:00 (0:00) is the scheduled playback start time. The item “endtime” on the 10th line indicates the scheduled playback end time of the content. In this example, 6 o'clock (6:00) is the scheduled playback end time.

  From the 12th line to the 15th line, additional information regarding this content is described. The item “title” on the 12th line indicates the title of this content. The item “author” on the 13th line indicates the creator of this content. The item “abstract” on the 14th line indicates an outline of the content. The character string described here is a summary character string displayed in transition processing and high-speed switching. The item “ref” on the 15th line indicates a reference destination to be referred to when acquiring this content. A parameter “href” described in the tag indicates a URL of a reference destination.

  In this example, the 7th to 16th lines indicate the following regarding a certain content. That is, this content is distributed from 0:00 to 6:00, the name is “weather FLASH”, the creator of this content is “CP-A”, Information ”, and when acquiring this content, the file at the URL“ http://www.cp-a.net/prd/weather.swf ”should be referred to.

  Information related to the contents described in the 17th to 26th lines is also composed of similar items. These descriptions will not be repeated here.

  The content reproduction device 60 refers to the item “ref” of the content list script 210 and acquires the data of the content. The content data itself provided by the content server 54 is uploaded to the URL described in this item. Alternatively, when the content is composite content, a composite media script describing information for synchronizing a plurality of contents constituting the composite media is uploaded.

  FIG. 8 shows an example of a composite media script provided by the content server 54 (see FIG. 1). Referring to FIG. 8, the composite media script 220 has a text file format and an XML format. The first line is a line for declaring that the information is described in the XML format.

  The tag “<smil>” on the second line and the tag “</ smil>” on the 40th line are SMIL, which is a multimedia description language defined by W3C (World Wide Web Consortium). It shows that it complies with (Synchronized Media Integration Language).

  Between the tag “<head>” on the 3rd line and the tag “</ head>” on the 18th line, information of each content constituting the composite media is included in the information for controlling the playback of the composite media. Information excluding playback timing is described. Between the tag “<layout>” on the 4th line and the tag “</ layout>” on the 17th line, information related to the arrangement on the display screen when each content constituting the composite media is reproduced is described. Is done. The item “root-layout” described in the fifth to sixth lines indicates a background to be displayed when the composite media is played back. Parameters “width”, “height”, and “backgroundColor” in this item indicate the number of pixels in the background width direction, the number of pixels in the height direction, and the background color, respectively. The parameter value of the background color is expressed in a format in which the luminance of each element in the RGB (Red Green Blue) color system is designated by a 2-digit hexadecimal number and arranged after “#”. This example shows that a black (# 000000) background is displayed in a range of width “1024” pixels and height “768” pixels.

  The item “region” described in the 7th to 16th lines indicates the definition of the display area on the screen that is referred to when the individual contents constituting the composite medium are reproduced. The parameter “id” described in this item indicates an area name for identifying an area defined by this item. The parameters “top”, “bottom”, “left”, and “right” each indicate the position of the reference point of the region. The parameters “width” and “height” indicate the width and height of the region, respectively. The parameter “fit” indicates a content display method when there is a difference between the shape of the region and the shape of the content displayed in this region. The parameter “z-index” indicates a context for specifying which area should be displayed in front when areas defined by the respective items overlap on the screen.

  For example, the items described in the seventh to eighth lines are areas referred to by the name “opening”, and the reference point is 27.5% of the whole in the vertical direction from the upper end of the screen, and the left end of the screen. From the top left corner located at 20% of the entire screen, the width of the region is 60% of the width of the entire screen, the height is 45% of the entire screen, and the content has a shape different from the shape of this region Is reproduced, the display image of the content is converted so as to conform to the shape of the area, and the value indicating the context of this area is 5.

  Between the tag “<body>” on the 19th line and the tag “</ body>” on the 39th line, information for specifying individual contents constituting the composite media and information indicating the playback timing of the contents are included. be written. The parameter “repeatCount” in the tag on the 19th line is the content reproduction performed at the playback timing described between the tag “<body>” on the 19th line and the tag “</ body>” on the 39th line. Indicates the number of repetitions. The value “indefinit” of this parameter indicates that it is repeated infinitely.

  Between the tag “<seq>” on the 20th line and the tag “</ seq>” on the 38th line, a series of contents that are continuously played back are described. “<Par>” in the 21st, 27th, and 33rd lines indicates that a plurality of contents are simultaneously played back in parallel. The 26th, 32nd, In addition, between the tag “</ par>” on the 37th line, information specifying the content to be reproduced in parallel indicated by the “<par>” tag is described. The parameters “id” and “dur” in the tag “<par>” respectively indicate a name for identifying individual states that are reproduced in parallel and the duration of the state that is reproduced in parallel. .

  The item “ref” on the 22nd line to the 23rd line indicates individual animation content. Parameters “src”, “region”, and “type” in this item indicate the URL of the reference destination when this content is acquired, the area in which this content is to be reproduced, and the data type of this content, respectively. In this example, the data type is MIME (Multipurpose Internet Mail Extensions) type application / x-shockwave-flash (type = “application / x-shockwave-flash”) / p: It is acquired from “movie / chalk.swf” and is reproduced in an area referred to by the name “opening”.

  The item “text” on the 24th line indicates reproduction of character information. In this example, the content of text / plain (type = “text / plain”) having a data type of MIME is acquired from the URL of “http: //cp-b/text/chalk.txt” and “bottom”. Indicates that playback is to be performed in the area referenced by the name.

  The item “<prefetch>” on the 25th line indicates content prefetching processing to be performed at this timing. This example indicates that 500 kilobytes (mediaSize = “500 Kb”) are acquired in advance from the URL “http: //cp-b/movie/ammonia.swf”.

  The content list stored in the content list storage unit 110 (see FIG. 2) includes a reproduction schedule for each channel and additional information related to contents scheduled to be reproduced according to the reproduction schedule. FIG. 9 shows an example of the reproduction schedule. FIG. 10 shows an example of additional information. Referring to FIG. 9, reproduction schedule 240 reproduces contents 242A, 242B,..., 242I,... Scheduled for reproduction on each channel described in channel list script 200 (see FIG. 6). This is matrix information shown for each scheduled time zone. The scheduled playback time zone of each content is obtained by analyzing information indicated by the tag “<schedule>” of the content list script (see FIG. 7). For example, when the user performs a selection operation of the channel number “111” in the period from 0:00 to 6:00, “content 1” 242A should be reproduced.

  Referring to FIG. 10, additional information 250 corresponds to one of contents 242A, 242B,..., 242I,. In this example, the additional information 250 corresponds to “content 1” 242A shown in FIG. The additional information 250 is configured by information described in the “program” item of the content list script 210 (see FIG. 7). The additional information 250 includes a content title 252, a content summary 254, a content creator 256, a URL 258 to be referred to when acquiring the content, a playback start time and a playback end time indicating the scheduled playback end time. 260.

  FIG. 11 shows an example of a composite media playback schedule stored in the composite media playback schedule storage unit 146 (see FIG. 3). Referring to FIG. 11, composite media playback schedule 270 is information obtained by analyzing composite media script 220 shown in FIG. The composite media playback schedule 270 includes content 272A, 272B,..., 272F to be played back and output in each area on the time axis where the playback time of the content is 0, and content 274A to be prefetched in each section on the time axis. , 274B. For example, “animation 1” 272A and “text 1” 272B are reproduced in the interval from “0” to “60” after the start of reproduction, and “animation 2” should be prefetched at the same time zone. It is shown ("Anime 2 prefetch" 274A). “Animation 2” is the content 272C to be reproduced in the next section on the time axis.

  FIG. 12 shows the configuration of information stored in the prefetch plan storage unit 124 (see FIG. 2). Referring to FIG. 12, the prefetch plan storage unit 124 stores a minimum prefetch amount correspondence table 280 that indicates the data amount that should be acquired by the minimum prefetch process for each content data type, and the content to be prefetched. Pre-read information 282A, 282B,... Indicating attributes, and a queue 284 indicating content awaiting pre-read processing by the content pre-read unit 126. The queue 284 is a matrix in which the prefetch requests 290A, 290B,... Associated with the prefetch information 282A, 282B,... Are stored in the order of the prefetch schedule planned by the prefetch planning unit 122.

  FIG. 13 shows an example of the minimum prefetching amount correspondence table 280 shown in FIG. Referring to FIG. 13, minimum read-ahead amount correspondence table 280 includes entries for each content type, and each entry is the minimum for starting reproduction of content data type 300 and content of that data type. A minimum amount of prefetching 302 per unit screen size indicating a necessary data amount. When the prefetch planning unit 122 shown in FIG. 2 generates a prefetch request and the reproduction units 150A, 150B,... Of the reproduction component group 140 of the content reproduction unit 120 (see FIG. 3) This is referred to when notification is given to the switching control unit 116.

  FIG. 14 shows an example of the prefetch information 282 shown in FIG. Referring to FIG. 14, prefetch information 282 includes a URL 310 to be referred to when content is acquired, and a prefetch file name indicating the name of the content file acquired by content prefetch unit 126 and stored in content storage unit 128. 312, a size 314 that indicates the data amount of the entire content, and a read amount 316 that indicates the amount of data that has already been acquired for the content by the prefetch process. The prefetch information 282 further includes a prefetch state 318 that indicates the progress of the prefetch processing relating to the content, and a channel distance 320 that indicates the priority when the content prefetch processing is performed.

  The prefetch information 282 further includes a data type 322 and a reproduction time 324 of the prefetch information 282. Further, it includes a flag 326 indicating whether or not this content is currently being reproduced, and items indicating prefetch requests 290A, 290B,... (See FIG. 12) generated by the prefetch planning unit 122 shown in FIG. . The prefetch request item is performed according to the minimum prefetch request 328 indicating a request for acquiring data of the minimum amount of data necessary to start reproduction, the channel distance of the content, and the storage capacity of the content storage unit 128. And an additional prefetch request 330 for requesting additional prefetch processing. The information stored in these items is information for identifying the prefetch requests 290A, 290B,... Shown in FIG.

  The information stored in the prefetching state 318 includes, for example, four types of “initial state”, “prefetching request issued”, “minimum prefetching amount reading completion”, and “reading completion”. The prefetch information 282 is generated by each playback unit 150A of the playback component group 140 based on the additional information of the content shown in FIG. 10, and is changed as necessary by the content prefetch planning unit 122 and the content prefetch unit 126. The

  FIG. 15 shows an example of a prefetch request stored in the queue 284 shown in FIG. Referring to FIG. 15, prefetch request 290 includes a start byte 340 and an end byte 342 indicating the start position and end position of the portion acquired for the content indicated by prefetch information 282 (see FIG. 14). The prefetch request 290 further includes a prefetch request type 344 indicating whether the prefetch request is a minimum prefetch request or an additional prefetch request. The prefetch request 290 is stored in association with the prefetch information 282 by the minimum prefetch request 328 or the additional read request 330 of the prefetch information 282 (see FIG. 14).

  The content playback device 60 according to the present embodiment is realized by computer hardware, a program executed by the computer hardware, and data stored in the computer hardware. FIG. 16 shows an internal configuration of hardware of the content reproduction device 60. Referring to FIG. 16, content reproduction device 60 includes an input interface 360 that receives a signal from remote controller 160, a monitor 362, and a speaker 364. The content playback device 60 further includes a network interface 366 that provides a connection to a local area network (LAN) or the like. The content playback device 60 is further connected to a CPU (central processing unit) 368, an input interface 360, a monitor 362, a speaker 364, a network interface 366, a CPU 368, a bus 370, and a bus 370, a boot-up program, a program command And a memory 372 for storing system programs, work data, and the like.

  A computer program for realizing the function of the content reproduction device 60 is stored in the memory 372 at the time of shipment or the like. Alternatively, the program may be transmitted to the network interface 366 through the communication network 52 (see FIG. 1) and stored in the memory 372. The program may be loaded directly into the memory 372 via the communication network 52 when executed.

  This program includes a plurality of instructions for realizing the function of the content reproduction device 60. Some of the basic functions necessary for realizing this method are an operating system (OS) or a third-party program operating on the content playback apparatus 60, or modules of various tool kits installed in the content playback apparatus 60. Provided. Therefore, this program does not necessarily include all functions necessary for realizing the content reproduction device 60 of this embodiment. This program may include only instructions for executing the processing performed by the above-described content reproduction apparatus by calling an appropriate function or “tool” in a controlled manner so as to obtain a desired result. That's fine. The operation of the computer is well known and will not be repeated here.

  The content reproduction device 60 according to the present embodiment executes a main processing program for reproducing content and a prefetch processing program in parallel. Hereinafter, first, the control structure of the main process will be described with reference to FIGS. Next, the control structure of the content prefetch process will be described with reference to FIG.

  FIG. 17 is a flowchart showing the control structure of the main processing program. Referring to FIG. 17, the main processing program is activated in response to, for example, the user pressing the power button 162 of the remote controller 160 shown in FIG. 4, and is a step (hereinafter simply referred to as “S”) 400. The channel list script 200 (see FIG. 6) stored in advance is read and analyzed, and the content list script provider corresponding to each channel is specified. In S402, it is determined whether or not there is an unacquired content list script corresponding to the channel among the channels specified in S400. If not acquired, the process proceeds to S404. If already acquired, the process proceeds to S410.

  In S404, the content list script 210 (see FIG. 7) corresponding to the channel determined not to be acquired in S402 is acquired from the provider specified in S400. In S406, the content list script 210 acquired in S404 is analyzed, and the reproduction schedule and additional information of the channel are obtained. In subsequent S408, the reproduction schedule and additional information obtained in S404 are stored, and a content list is generated. Control returns to S402. By repeating the processes of steps S402 to S404, S406, and S408, a content list for all channels described in the channel list script 200 is generated. Control proceeds to S410.

  In S410, the process waits for an event to occur. If an event has occurred, control proceeds to S412. In S <b> 412, it is determined whether or not the generated event is an input event generated by a selection operation by the user. If it is an input event, the process proceeds to S414. Otherwise, the process proceeds to S420.

  In S414, the occurrence time of the input event is specified, and the input frequency is calculated in combination with the occurrence times specified in the past. In subsequent S416, it is determined whether or not the input frequency calculated in S414 has reached a predetermined value. If the predetermined frequency has been reached, the process proceeds to S418. Otherwise, the process proceeds to S422. In S418, high-speed content switching processing is performed, and the process returns to S410. Details of the fast switching process will be described later with reference to FIG.

  In S420, it is determined whether the generated event is a timer event. If a timer event has occurred, the process proceeds to S422. Otherwise, the process returns to S410. In S422, a content switching process for switching the content to be reproduced is performed, and the process returns to S410. Details of the process of S422 will be described later with reference to FIG.

  FIG. 18 is a flowchart showing a detailed control structure of the content switching process executed in S422 of FIG. Referring to FIG. 18, when the content switching process 440 is started, in S442, the content list is referred to, and additional information about the content being distributed on the currently selected channel is read. In S444, the pre-read information about the content indicated by the additional information read in S442 is referred to, and it is determined whether or not the reproduction preparation of the content is completed and the reproduction can be started. If it is ready to start playback, the process proceeds to S446. Otherwise, the process proceeds to S450.

  In S446, the content is reproduced based on the additional information read in S442. In subsequent S448, additional information is specified for the end time of the content started to be played in S446, and a timer is set to switch to the next content when the time is reached. The process proceeds to S454.

  On the other hand, in S450, the transition time from the current time point to the point at which playback can be started is calculated, and the transition process corresponding to the calculated transition time is performed on the playback output of the content being played back. In S452, a timer setting for switching is performed when the end time of the transition time calculated in S450, that is, the time at which reproduction is possible is reached. The process proceeds to S454.

  In S454, the content list is searched, and from the content selected at that time, the additional information of a plurality of adjacent contents on the reproduction schedule is specified as the content to be pre-read, and the additional information about the specified content is read. put out.

  In S456, for one of the additional information read in S454, it is determined whether the pre-read information corresponding to the content indicated by the additional information is not updated or has been updated. If there is no prefetch information or it has not been updated, the process proceeds to S458. If all the prefetch information has been updated, the content switching process 440 is terminated.

  In S458, the minimum prefetching amount and the additional prefetching amount are calculated for the prefetching information corresponding to the additional information determined in S456, and the prefetching information is updated. In S460, the minimum prefetching amount and the additional prefetching amount updated in S458 are compared with the content prefetching information to determine whether or not prefetching processing is necessary. If prefetch processing is necessary, the process proceeds to S462. Otherwise, the process returns to S456. In S462, a minimum prefetch request and an additional prefetch request for the content determined to require prefetch processing in S460 are issued, stored in the queue in the order corresponding to the prefetch distance, and the process returns to S456.

  The steps from S456 to S462 are executed for all the additional information read in S454, and if it is determined in S456 that there is no unread preread information, the content switching process ends.

  FIG. 19 is a flowchart showing a detailed control structure of the fast switching process executed in S418 shown in FIG. Referring to FIG. 19, when the high-speed switching process 480 is started, in S482, the content list is referred to, and the channel that distributes the currently selected content and the multiple channels whose channel numbers are close to each other are Read additional information about the content provided at the time. A summary character string included in each of the additional information is read out, and a summary display of content is created and displayed. In S484, a timer is set in order to end the fast switching process after a predetermined time has elapsed. Control proceeds to S486.

  In S486, an event for the outline display of the content started in S482 is awaited. If an event has occurred, the process proceeds to S488. In S488, it is determined whether or not the event that has occurred is an input event. If it is an input event, the process returns to S482. Otherwise, go to S490. In S490, it is determined whether or not the event that has occurred is a timer event. If it is a timer event, the process proceeds to S492, the content switching process 440 (see FIG. 18) is performed, and the high-speed switching process 480 is terminated. Otherwise, the process returns to S486.

  FIG. 20 is a flowchart showing a control structure of a prefetch process executed in parallel with the main process shown in FIGS. Referring to FIG. 20, when prefetch process 500 is started, in S502, the process waits for a prefetch request to be stored in the prefetch request queue. If the prefetch request is stored in the queue, the process proceeds to S504, where the prefetch request stored at the head of the queue is read, and the content to be acquired is referred to by referring to the prefetch information corresponding to the prefetch request. Identify. In S506, communication with the content server 54 is performed, and the data of the content specified in S504 is acquired and stored in the amount of data specified by the prefetch request. In S508, based on the processing result in S506, the prefetch information and the prefetch request queue are updated. Control returns to S502.

  The content reproduction device 60 according to the present embodiment operates as follows.

(Overview of operation)
The content reproduction device 60 prepares a content list when the content reproduction device 60 is activated. Further, in response to an input signal from the input unit 114, the content to be reproduced is determined based on the content list and reproduced. However, there is a risk of waiting time due to the time required for communication processing when switching content. In order to cope with this, the content reproduction device 60 performs the following three types of operations. That is, it is determined whether or not a sufficient amount of content to be played back is stored to cope with the waiting time, and in response to obtaining a determination result that sufficient data is not stored, the prefetch plan While making a content acquisition request to the unit 122, a predetermined transition effect is added to the reproduction output until sufficient data is acquired. In response to obtaining the determination result that the content to be reproduced is stored, the stored content is read and reproduced. When the input signal is frequently generated, display for causing the user to select the content is performed for a predetermined time.

  When the content switching is completed, the content that is likely to be selected next by the user is selected, its priority is determined, a prefetching plan is performed, and the prefetch request queue is updated. In parallel with the above-described operation, the content to be prefetched is acquired and stored in accordance with the prefetch request stored in the queue.

(Preparing the content list)
The content reproduction device 60 is activated in response to, for example, the user pressing the power button 162 of the remote control 160 shown in FIG. At this time, the input unit 114 shown in FIG. 2 generates an activation signal in response to an operation by the user.

  Referring to FIG. 2, channel list script analysis unit 104 reads channel list script 200 (see FIG. 6) from channel list script storage unit 102 in response to the activation signal. The channel list script analysis unit 104 analyzes the read channel list script 200 and identifies the channel number, the service type, and the corresponding service identifier for each individual channel shown in FIG. When the service format is “NetContents”, the channel list script analysis unit 104 gives the URL, which is the identifier of the service, to the content list script acquisition unit 106 for each channel, and issues a content list script acquisition command. .

  In response to the acquisition command from the channel list script analysis unit 104, the content list script acquisition unit 106 receives, for each channel, from the content list information server 56 connected to the communication network 52 shown in FIG. Get content list.

  When acquiring the content list script, the content list script acquisition unit 106 performs, for example, the following operation. That is, the content list script acquisition unit 106 first creates a content list script acquisition request using a predetermined acquisition condition as a parameter, and transmits it to the content list information server 56 shown in FIG. 1 via the network communication unit 100. . Typically, the parameters are encoded and transmitted in the message body of a POST request of HTTP (HyperText Transfer Protocol). Alternatively, the parameter is encoded as a query character string of an HTTP GET request.

  The content list information server 56 illustrated in FIG. 1 receives an acquisition request from the content reproduction device 60 via the communication network 52. The content list information server 56 prepares the content list script 210 (see FIG. 7) based on the acquisition conditions included in the acquisition request, and returns it to the content reproduction device 60 that is the transmission source of the acquisition request.

  Referring to FIG. 2, content list script acquisition unit 106 transmits the content list script 210 transmitted from content list information server 56 in response to the transmitted acquisition request, to the channel number and channel number given from channel list script analysis unit 104. The contents list script analysis unit 108 is provided together with information indicating the service format.

  The content list script analysis unit 108 analyzes the given content list script 210 and specifies a scheduled reproduction time zone for each content described in the content list script 210. The content list script analysis unit 108 updates the reproduction schedule 240 shown in FIG. 9 of the content list stored in the content list storage unit 110 based on the specified scheduled reproduction time zone. Further, for each content described in the content list script 210, additional information 250 (see FIG. 10) is generated and stored in the content list storage unit 110 in association with the reproduction schedule 240.

  The content list script acquisition unit 106, the content list script analysis unit 108, and the content list storage unit 110 follow all channel acquisition commands issued by the channel list script analysis unit 104 for all channels that can be played back by the content playback device 60. The content list is updated.

(Content switching operation)
In the following, among the operations for switching content in response to an input, it is determined whether or not a sufficient amount of content to be played back is stored to cope with the waiting time, and sufficient data is stored. An operation of reading and playing back the stored content in response to obtaining the determination result will be described.

  When the user performs a selection operation by pressing the channel selection button 166 or the numeric button 174 of the remote controller 160 shown in FIG. 4, the input unit 114 shown in FIG. 2 generates an input signal corresponding to the selection operation. The content switching control unit 116 refers to the reproduction schedule (see FIG. 9) stored in the content list storage unit 110 in response to the generated input signal, and the content to be reproduced at that time in the channel selected by the user Is identified. The content switching control unit 116 reads additional information of the identified content from the content list storage unit 110. The outline character string included in the read additional information is given to the reproduction component group 140 shown in FIG. 3 of the content reproduction unit 120, and commanded to be combined with the output of the content being reproduced and displayed. The content switching control unit 116 further gives the read additional information to the composite media playback control unit 148 of the content 120.

  Referring to FIG. 3, each playback unit 150A, 150B,... Constituting the playback component group 140 of the content playback unit 120 is the content being played back in a predetermined method in response to the outline character string being given. The display output of the summary character string is synthesized with the output of and reproduced. On the other hand, the composite media playback control unit 148 receives content additional information 250 (see FIG. 10) to be played back from the content switching control unit 116 shown in FIG. The composite media playback control unit 148 determines the data type of the content to be played based on the URL of the additional information 250. In response to the determined data type being other than the composite media, the composite media playback control unit 148 provides the additional information 250 to the playback units 150A, 150B,... Corresponding to the data type of the playback component group 140. .

  The composite media playback control unit 148 also searches and reads the composite media playback schedule 270 (see FIG. 11) stored in the composite media playback schedule storage unit 146 in response to the data type being composite content. . When the search for the composite media playback schedule fails, the composite media playback control unit 148 gives the URL included in the additional information to the composite media script acquisition unit 142. Based on the given URL, the composite media script acquisition unit 142 acquires the composite media script 220 (see FIG. 8) from the content server 54 shown in FIG. 1 via the network communication unit 100, and the composite media script analysis unit 144. To give. The composite media script analysis unit 144 analyzes the given composite media script, generates a composite media playback schedule 270 (see FIG. 11), and provides the composite media playback schedule storage unit 146 with it. The composite media playback schedule storage unit 146 stores the given composite media playback schedule 270 and gives it to the composite media playback control unit 148.

  The composite media playback control unit 148 calculates the elapsed time from the scheduled playback start time of the composite media based on the playback time 260 included in the additional information 250 (see FIG. 10). The composite media playback control unit 148 further specifies the content to be played back at the present time based on the playback timing and the calculated elapsed time in the composite media playback schedule 270 (see FIG. 11) obtained from the composite media playback schedule storage unit 146. . The composite media playback control unit 148 generates individual additional information for each identified content based on the additional information 250 and the composite media playback schedule 270. Further, the data type is determined for each of the specified contents, and the generated individual additional information is given to the corresponding playback units 150A, 150B,... Of the playback component group 140 according to the determination result.

  Reproducing units 150A, 150B,... Use prefetched information 282 (see FIG. 14) stored in prefetched plan storage unit 124 shown in FIG. Search through. Further, with reference to the prefetching state 318 of the prefetched information 282 searched, it is determined whether or not the content reproduction preparation is completed. The prefetching state 318 is “minimum prefetching amount reading complete”, that is, the state where content acquisition based on the minimum prefetching request is completed, or “reading complete”, ie, content acquisition based on the content additional prefetching request is also completed. If it is in the state, it is determined that the content reproduction preparation is completed. In response to the determination result indicating that the preparation for reproduction has been completed, the reproducing units 150A, 150B,...

  Referring to FIG. 2, upon receiving notification of completion of playback preparation from content playback unit 120, content switching control unit 116 gives additional information to content playback unit 120 and instructs playback of the content.

  Referring to FIG. 3, the composite media playback control unit 148 of the content playback unit 120 and the playback units 150A, 150B,... Of the playback component group 140 complete the preparation for playback of content by the same operation as described above. It is determined whether or not it is. In response to determining that the preparation for reproduction is completed, the composite media reproduction control unit 148 of the content reproduction unit 120 notifies the content switching control unit 116 of the completion of preparation. Upon receiving notification of completion of playback preparation from the content playback unit 120, the content switching control unit 116 gives additional information to the content playback unit 120 and instructs playback of the content. The content reproduction instruction is given to the composite media reproduction control unit 148 shown in FIG.

  When the composite media playback control unit 148 receives the content playback instruction, the composite media playback control unit 148 causes the animation playback unit 150A, the text playback unit 150B, the still image playback unit 150C, and the video playback unit 150D to stop the currently played content. Instruct. Subsequently, the composite media playback control unit 148 refers to the URL of the given content additional information, and determines the data type of the content indicated by the additional information.

  For example, when the content data type is animation, the composite media playback control unit 148 instructs the animation playback unit 150A to play back. The animation reproducing unit 150A retrieves the content prefetch information from the prefetch plan storage unit 124 using the URL of the content additional information as a search key, and reads the prefetch file name 312 from the retrieved content prefetch information 282 (see FIG. 14). The content file is read from the content storage unit 128 by specifying a prefetch file name, and the animation is played back. The animation reproducing unit 150A reads the size 314 and the read amount 316 from the searched content prefetch information 282, and provides the read content 316 to the content switching control unit 116 (see FIG. 2).

  When the data type of the content is text, a playback instruction is given to the text playback unit 150B. The text playback unit 150B performs text playback by the same operation as the animation playback unit 150A. When the content data type is a still image, a reproduction instruction is given to the still image reproduction unit 150C. The still image reproduction unit 150C performs the reproduction of the still image by the same operation as the animation reproduction unit 150A. When the content data type is a moving image, a reproduction instruction is given to the moving image reproduction unit 150D. The moving image reproduction unit 150D performs the reproduction of the moving image by the same operation as the animation reproduction unit 150A.

  When the data type of the content is composite media, the composite media playback control unit 148 searches the composite media playback schedule storage unit 146 for the composite media playback schedule 270 (see FIG. 11) corresponding to the composite media. In addition, the composite media playback control unit 148 obtains the difference between the current time and the playback start time of the additional information, and calculates the elapsed time after the start of playback. The composite media playback control unit 148 refers to the searched composite media playback schedule 270 and specifies the content to be played back at the calculated elapsed time.

  The composite media playback control unit 148 determines the data type of the identified content, and instructs the playback unit corresponding to the data type to play back. The composite media playback control unit 148 calculates the sum of the size and the read amount for each identified content, and gives the sum to the content switching control unit 116. The content switching control unit 116 displays the content size and the read amount obtained from the content reproduction unit 120 on the content summary display.

  With the above operation, the content stored in the content storage unit 128 is searched based on the pre-read information, and the reproduction of the content is started without waiting time.

(Transition processing)
Hereinafter, it is determined whether or not a sufficient amount of content to be played back is stored to cope with the waiting time, and in response to obtaining a determination result that it is not stored, the prefetch planning unit 122 is An operation of making a predetermined transition effect on the reproduction output while making a content acquisition request and until sufficient data is acquired will be described.

  When the user performs a selection operation similar to the content switching operation described above, the input unit 114 shown in FIG. 2 generates an input signal corresponding to the selection operation. In response to the input signal, the content switching control unit 116 refers to the reproduction schedule 240 (see FIG. 9) stored in the content list storage unit 110, identifies the content to be reproduced, and reads the additional information of the content To the content reproduction unit 120.

  Referring to FIG. 3, composite media playback control unit 148 receives additional information 250 (see FIG. 10). The composite media playback control unit 148 determines the data type of the content to be played based on the URL of the additional information 250. In response to the fact that the data type is other than the composite media, the composite media playback control unit 148 provides the additional information 250 to the playback units 150A, 150B,... Corresponding to the data type of the playback component group 140.

  In response to the fact that the data type is composite content, the composite media playback control unit 148 obtains the composite media playback schedule 270 (see FIG. 11) by the same operation as the content switching operation described above. The composite media playback control unit 148 calculates the elapsed time based on the playback time 260 included in the additional information 250 (see FIG. 10), and determines the playback timing in the composite media playback schedule 270 (see FIG. 11) and the calculated elapsed time. Based on this, the content to be reproduced at the present time is specified. The composite media playback control unit 148 generates individual additional information for each identified content. Further, the data type is determined for each of the specified contents, and the generated individual additional information is given to the corresponding playback units 150A, 150B,... Of the playback component group 140 according to the determination result.

  Reproducing units 150A, 150B,... Use prefetched information 282 (see FIG. 14) stored in prefetched plan storage unit 124 shown in FIG. Search through. Further, with reference to the prefetching state 318 of the prefetched information 282 searched, it is determined whether or not the content reproduction preparation is completed. When the search fails, or when it is determined by the pre-read information obtained by the search that the content playback preparation is not completed, the playback units 150A, 150B,... Prefetch information 282 is generated and given to the prefetch planning unit 122 shown in FIG. Further, in the minimum prefetch amount correspondence table 280 (see FIG. 13) from the prefetch plan storage unit 124, the minimum prefetch amount 302 corresponding to the data type corresponding to the reproduction units 150A, 150B,. This is given to the reproduction control unit 148.

  The composite media playback control unit 148 receives notification of the minimum amount of prefetching from each of the playback units 150A, 150B,... That has given the additional information, and calculates the sum of them. The composite media playback control unit 148 gives the calculated sum total of the minimum amount of prefetching to the content switching control unit 116.

  When the content playback unit 120 gives the minimum content prefetching amount and the communication speed of the content playback device 60, the time required to acquire the content with the minimum prefetching amount is calculated based on the given information. The content switching control unit 116 gives the calculated time information to the timer 118 and the content reproduction unit 120.

  Referring to FIG. 3, when content reproduction unit 120 receives time information, reproduction by animation reproduction unit 150A, text reproduction unit 150B, still image reproduction unit 150C, moving image reproduction unit 150D and the like constituting reproduction component group 140 is performed. The part applies the transition effect to the content being played back for a specified time. The timer 118 starts timing in response to receiving the time information, and gives a notification to the content switching control unit 116 when the calculated time has elapsed.

  In response to the notification from the timer 118, the content switching control unit 116 reads the additional information and provides the content reproduction unit 120 with the same operation as the above-described operation.

  FIG. 21 shows an example of screen transition of the content reproduction device 60 when the content is switched by the series of operations described above. Referring to FIG. 21, it is assumed that playback component group 140 shown in FIG. At this time, the outline character string 602 is displayed together with the content 600 by the output from the content switching control unit 116. When the user makes a selection input, the playback output screen of the content playback device 60 transitions to the playback output 610. The reproduction output 610 is obtained by applying a transition effect to the reproduction output of the content 600. Further, the displayed summary character string is a content summary character string 612 that is output after the content is switched. When the content switching preparation is completed, the playback output screen of the content playback device 60 transitions to the content 620 of the selected channel. The summary character string 622 displayed at this time is the same as the summary character string 612 displayed during the transition process.

  FIG. 22 shows an example of content size and read amount display by the content playback device 60. Referring to FIG. 22, content switching control unit 116 displays summary character string 632, bar graph 634 having a length proportional to the size of content 630 and the read amount, and numeric value 636 of the content size and read amount. .

  The content switching control unit 116 searches the content list stored in the content list storage unit 110, and refers to the additional information of the content to be reproduced next to the content to be reproduced on the channel selected at the current time. The content switching control unit 116 sets the reproduction start time of the next content indicated by the referenced additional information in the timer 118.

(Content prefetching)
When the content switching by the content playback unit 120 is completed, the content switching control unit 116 refers to the content list storage unit 110 and is positioned in the vicinity on the content currently being played back and the playback schedule 240 (see FIG. 9). Identify content.

  For example, it is assumed that the currently reproduced content is “content 4” belonging to the content list information of the channel number “113” on the reproduction schedule 240 shown in FIG. In this case, “content 3” and “content 5” that belong to the content list information of the same channel as the content 4 and whose playback order is adjacent to “content 4” are specified as the content located in the vicinity. In addition, in the content list information of the channel number “111” and the channel number “117” in which the channel number “113” to which the “content 4” belongs and the channel number are adjacent to each other, the reproduction in the same time zone as the “content 4” Scheduled “content 1” and “content 8” are also specified as content located in the vicinity.

  The content switching control unit 116 reads the additional information of the identified content, and generates distance information indicating the positional relationship on the reproduction schedule 240 between the currently reproduced content and the identified content. The content switching control unit 116 gives the read additional information to the content reproduction unit 120 and instructs the prefetch processing of the specified content.

  The composite media playback control unit 148 determines the data type of the content corresponding to the URL of the additional information in response to receiving the distance information and the additional information from the content switching control unit 116 shown in FIG. A prefetch processing command is given to the reproducing units 150A, 150B,.

  For example, when the data type of the content is animation, a prefetch processing command is given to the animation reproducing unit 150A. When receiving the prefetching instruction, the animation reproducing unit 150A searches the prefetching information stored in the prefetching plan storage unit 124 using the URL of the additional information as a search key. When the prefetch information is not found, the animation reproducing unit 150A generates content prefetch information, and sets the URL, data type, reproduction start time, and reproduction end time information stored in the additional information.

  When the data type is composite media, the composite media playback control unit 148 searches and reads the composite media playback schedule storage unit 146 based on the URL included in the additional information. When the composite media playback schedule is not stored in the composite media playback schedule storage unit 146, the URL included in the additional information is given to the composite media script acquisition unit 142 by the same operation as that at the time of content switching, so that the content is Get a composite media playback schedule.

  The composite media playback control unit 148 refers to the obtained composite media playback schedule and identifies individual contents included in the composite media. The composite media playback control unit 148 determines the data type for each identified content, and the corresponding playback unit 150A, 150B,... Displays the distance indicated by the content list, the URL of each content, and the playback indicated by the content additional information. A start time and a playback end time are given.

  The composite media playback control unit 148 further refers to the obtained composite media playback schedule, and specifies the content to be prefetched at that time from the difference between the current time and the playback start time of the additional information of the content. For example, when the additional information indicates that the composite media in the composite media playback schedule 270 shown in FIG. 11 is played from 6 o'clock to 8 o'clock, a pre-read processing command is received for this composite media at 6:02. Then, “animation 3” 274B is specified as the content to be prefetched at 120 seconds from the start of reproduction.

  The composite media playback control unit 148 acquires a URL corresponding to the specified individual content from the composite media playback schedule, and uses the acquired URL as a search key to store the prefetch stored in the prefetch plan storage unit 124 illustrated in FIG. Search for information. If the search for the prefetch information fails, the composite media playback control unit 148 generates prefetch information for the individual content, and the URL of the composite media, the playback start time, and the playback end time indicated by the given additional information. Identify information and identified data types. The composite media playback control unit 148 further generates prefetch information based on the distance information about the composite media, the URL of the composite media, the prefetch size, and the specified information, and the prefetch planning unit 122 shown in FIG. To give. For example, in the prefetch of animation 3 shown in FIG. 9, the prefetch size is designated as 500 kilobytes (mediaSize = “500 Kb”).

  Referring to FIG. 2, in response to receiving prefetch information from content reproduction unit 120, prefetch planning unit 122 first deletes a prefetch request for the content indicated by the prefetch information from the queue. Next, the prefetch planning unit 122 reads the content prefetching information and determines whether the content is being reproduced. When it is determined that the content is being reproduced, the prefetch planning unit 122 sets the minimum prefetch amount to infinity. In other cases, the minimum prefetching amount correspondence table 280 stored in the prefetching plan storage unit 124 is referred to, and the minimum prefetching amount and the additional prefetching amount of the content are calculated and stored in the prefetching information. However, when the minimum prefetching amount is stored in advance by the composite media playback control unit 148 shown in FIG. 3, the minimum prefetching amount is not stored, and the minimum prefetching amount set by the composite media playback control unit 148 is prioritized.

  The prefetch planning unit 122 creates a minimum prefetch request for acquiring up to the minimum prefetch amount in which the content specified by the prefetch information is set. At this time, if the minimum prefetching amount is larger than the read amount stored in the content prefetching information, the prefetching planning unit 122 creates a minimum prefetching request and changes the state of the content prefetching information to “prefetching scheduled”. Otherwise, the state of the content prefetch information is changed to “minimum prefetch amount read completion”. Next, the prefetch planning unit 122 calculates and sets an additional prefetch amount from each item of the content prefetch information. For example, according to the formula of (5-channel distance) × 500 kilobytes, a larger amount of additional prefetching is set for a content with a shorter channel distance. The prefetch planning unit 122 creates an additional prefetch request for acquiring up to the set additional prefetch amount. At this time, if the sum of the set additional prefetching amount and the minimum prefetching amount is larger than the read amount of the content prefetching information, the prefetch planning unit 122 creates a content prefetching request. Conversely, if the sum of the additional read-ahead amount and the minimum read-ahead amount set is less than the read amount of the content pre-read information, a part of the read-ahead file that has already been read is deleted, and the additional read-ahead amount and the minimum file size are set. The state of the content prefetching information is set to “reading complete” so as to be the sum of the prefetching amount.

  Next, the prefetch planning unit 122 calculates a priority for determining the order of prefetching for the generated prefetching request. At this time, the prefetch planning unit 122 calculates the priority so that the priority of the minimum prefetch request is higher than the priority of the additional prefetch request. For example, the priority is calculated by the formula of 1000+ (5-channel distance) for the lowest prefetch request, and the priority is calculated by the formula of (5-channel distance) for the additional prefetch request. Next, the prefetch planning unit 122 adds the generated prefetch request to the queue so that a prefetch request having a higher priority is arranged at the front of the queue.

  The content switching control unit 116, the content reproduction unit 120, and the prefetch planning unit 122 perform the above operations on the content additional information referred to by the content switching control unit 116, respectively.

  In parallel with the above processing, the content prefetching unit 126 acquires content according to the prefetch request. The content prefetch unit 126 monitors the queue 284 (see FIG. 12) stored in the prefetch storage unit 124, and waits for a content prefetch request to be added if the queue is empty.

  When the prefetch request unit 290A is stored in the queue 284 by the prefetch plan unit 122, the content prefetch unit 126 reads the content prefetch request stored at the head of the queue 284. The content prefetching unit 126 refers to the URL stored in the prefetching information 282 (see FIG. 14) corresponding to the content prefetching request, and specifies the position of the content to be acquired on the communication network 52 shown in FIG. To do. The content prefetching unit 126 generates a transmission request for requesting the content server 54 shown in FIG. 1 to transmit the amount specified in the prefetching request among the data forming the specified content. The content prefetching unit 126 transmits the generated transmission request to the content server 54 via the network communication unit 100.

  Referring to FIG. 1, when content server 54 receives a content reproduction request from content reproduction device 60, content server 54 refers to the information on the amount of data included in the transmission request, and the requested data amount of the content data is requested. Only to the content reproduction device 60 that is the transmission source of the acquisition request.

  The content prefetch unit 126 of the content reproduction device 60 receives a predetermined amount of data transmitted from the content server 54 via the network communication unit 100. The content prefetching unit 126 stores the received data in the content storage unit 128 as the prefetching file name of the content prefetching information corresponding to the content prefetching request. Further, the content prefetch unit 126 adds the data amount of the acquired data to the value stored in the read amount 316 of the prefetch information 282 corresponding to the prefetch request. Further, referring to the prefetch state 318 of the prefetch information 282, if the information of this item is “issue of prefetch request”, it is updated to “minimum prefetch amount read completion”. If the information of this item is “minimum read-ahead read completion”, the information is updated to “read complete”. The content prefetching unit 126 sequentially executes the above processing for the content prefetching requests in the queue.

(High speed switching)
When the user presses the channel selection button 166 or the numeric button 174 of the remote controller 160 shown in FIG. 4 to perform a selection operation for switching content, the input unit 114 shown in FIG. 2 generates an input signal corresponding to the selection operation, This is given to the content switching control unit 116. When the operation input signal is given, the content switching control unit 116 stores the input time. The content switching control unit 116 calculates the time difference between the input time of the input signal received n times before and the input time of the input signal received last.

  The content switching control unit 116 starts high-speed switching of content when the calculated time difference is smaller than a predetermined value, that is, when n or more selection operations are performed within a predetermined time. The content switching control unit 116 searches the content list stored in the content list storage unit 110, and adds the additional information of the content to be played back on the channel selected at the current time and the addition of the content played back at the current time on the previous and subsequent m channels Browse for information. The content switching control unit 116 reads the content outline character string from the referenced additional information, and generates and outputs a list display screen of the content outline character string.

  FIG. 23 shows an example of the display of the playback screen when the content playback device 60 performs high-speed switching. Referring to FIG. 23, it is assumed that the content reproduction apparatus displays a screen 600 similar to the screen shown in FIG. 21 before the high-speed switching is started. When the high-speed switching is started, as shown in the screen 640, the content outline character strings 642A, 642B, 642C, and 642D are displayed side by side without changing the content reproduction display. If no input is made by the user for a certain period, the high-speed switching ends. As shown in a screen 650, the screen is switched to the content selected at that time.

  The content switching control unit 116 shown in FIG. 2 displays the display of the outline character string 642A,... For the currently reproduced content, for example, by changing the thickness of the display frame or changing the background color or pattern. This indicates that the channel is currently selected.

  The content switching control unit 116 sets the timer 118 so that a high-speed switching end notification is made after a predetermined time. When the content switching control unit 116 receives an input signal of a selection operation for switching content, the content switching control unit 116 reproduces at the current time on the selected channel and the preceding and following n channels in the same manner as the operation performed at the start of high-speed content switching. The content summary display is arranged and output to the screen. The content switching control unit 116 resets the timer 118 so that a high-speed switching end notification is made after a predetermined time from the current time.

  The timer 118 notifies the content switching control unit 116 in response to reaching the set time without resetting after setting the timer. In response to the notification from the timer 118, the content switching control unit 116 reads the additional information of the content and gives it to the content playback unit 120 in order to start playback of the content currently selected. The content playback unit 120 starts playback of the selected content through the above-described content switching process.

  Note that the content switching control unit 116 also inquires the content reproduction unit 120 about the size and read amount for each content for which the summary character string is to be displayed when the summary character strings are arranged and output on the screen in high-speed switching. As shown in FIG. 24, the size and the read amount may be displayed on the content summary display.

  As described above, the content reproduction device 60 according to the present embodiment determines the prefetch amount of content based on the order of the content indicated by the content list, and prefetches that much. Therefore, even when the file size is large, the amount of data necessary for reproduction can be acquired for a large number of contents. Further, even when there are a large number of content files, a larger number of contents can be acquired. Therefore, the storage area can be used efficiently. In addition, the content reproduction device 60 assigns the content prefetching order based on the order relation included in the content list. Accordingly, since it is possible to pre-read the content that has a high possibility of being selected, the waiting time at the start of content reproduction can be reduced.

  Furthermore, by applying the transition effect at the time of content switching, the user can predict the waiting time that occurs. Further, by performing high-speed switching, it is possible to avoid a state in which a waiting time continues to occur because the communication process is repeated in conjunction with the user repeating the selection operation. The user can quickly select content, and can reduce the waiting time after the user selects content.

  In the embodiment described above, the composite media playback control unit 148 shown in FIG. 3 determines the data type of the content. However, the present invention is not limited to such an embodiment. For example, based on the URL included in the additional information, the content switching control unit 116 shown in FIG. 2 determines the data type of the content and selectively gives the additional information to the playback unit of the playback component group 140 shown in FIG. You may do it.

  Note that, in the above-described embodiments, a service for reproducing Internet content has been described as an example. However, the present invention is not limited to such an embodiment. For example, an entity of a service for reproducing a television broadcast provided using a predetermined frequency of a broadcast wave, or a service for reproducing an electronic mail or a composite media message received from the Internet may be used as a channel.

  FIG. 25 shows an example of the channel list script in such a case. Referring to FIG. 25, the item “<channel>” on the 12th line of the channel list script 740 indicates a channel (src = “tv: //mhk.jp/sougou/”) of a television broadcast (type = “TvBroadCast”). ) Shows the service that plays. In addition, the item “<channel>” on the 13th line indicates a service for reproducing the receiving box (src = “ReceiveBox”) of the electronic mail (type = “MailApp”). Even in the case where such a channel list script 740 is prepared, the content playback device 60, in the channel for playing back Internet content in accordance with the content list script acquired from the content list information server 56, similarly to the above-described embodiment. Internet content prefetching processing can be performed.

  Note that when a broadcast service or the like is handled as a channel having the service as an entity, the alternative content may be displayed during a waiting time until reproduction of another channel is started. In the example shown in FIG. 25, the item “<channel>” on the 12th line indicates that “alt.jpg” (alt = “alt.jpg”) is displayed as the substitute image.

  Further, in the present embodiment, when the preparation for reproducing the content is not completed, the processing for switching the content is performed after applying a predetermined time transition effect to the original content. However, the present invention is not limited to such an embodiment. For example, instead of applying the transition effect, fast content switching may be performed during the generated waiting time. In such a case, the content may be switched after the alternative content is reproduced for a predetermined time.

  Further, the composite media script is described so that the media to be played is switched according to the remaining amount of the temporarily storable area, and the composite media playback control unit 148 plays the media according to the remaining amount of the temporarily storable area of the content storage unit 128. May be selected and played back. FIG. 26 shows a part of the composite media script in such a case.

  Referring to FIG. 26, media candidates to be played are listed in order between “<switch>” on the first line and “</ switch>” on the seventh line of composite media script 750. The item “<ref>” in the second to third lines indicates that the URL is “http: // cp-b /” when the remaining amount of the area that can be temporarily stored is 10 megabytes or more (systemCacheSize = “10 Mb”). “movie / chalk.swf” is reproduced. The item “<img>” in the 4th to 5th lines is the case where the item “<ref>” in the 2nd to 3rd lines is not selected, and the remaining amount of the area that can be temporarily stored is 1 megabyte or more. When (systemCacheSize = “1 Mb”), the media acquired from “http: //cp-b/img/chalk.jpg” is reproduced. The item “<text>” on the sixth line is “http: // cp−” when the items “<ref>” and “<img>” on the second to fifth lines are not selected. This indicates that the medium acquired from “b / text / chalk.txt” is played.

  Note that the timing of performing the content list acquisition and update processing is not limited to when the content playback device 60 is activated. For example, it may be performed when the user performs a predetermined input operation or when a predetermined notification is received from the content list information server 56. In the content switching process, both the content and the content summary display are displayed, but only one of them may be reproduced. In the prefetching process, the content of a channel randomly selected by a random number may be selected as a prefetching target.

  The condition when the content list script acquisition unit 106 acquires the content list script may be, for example, a condition that the title name of the content list script includes a predetermined character string. Further, for example, the content list information server may be a condition of content recommended to the content reproduction device 60 or its user.

  The embodiment disclosed herein is merely an example, and the present invention is not limited to the above-described embodiment. The scope of the present invention is indicated by each claim in the claims after taking into account the description of the detailed description of the invention, and all modifications within the meaning and scope equivalent to the wording described therein are intended. Including.

It is a figure which shows the whole structure of the system containing the content reproduction apparatus 60 which concerns on embodiment of this invention. 3 is a block diagram showing a functional configuration of a content reproduction device 60. FIG. FIG. 3 is a diagram illustrating a configuration of a content reproduction unit 120 illustrated in FIG. 2. FIG. 3 is a diagram showing an example of button arrangement of a remote controller 160 that constitutes an input unit 114 shown in FIG. 2. It is the schematic which shows the relationship between a service, a channel, and a content list script. It is a figure which shows an example of a channel list script. It is a figure which shows an example of a content list script. It is a figure which shows an example of a composite media script. It is a figure which shows an example of a reproduction schedule. It is a figure which shows an example of additional information. It is a figure which shows an example of a composite media reproduction schedule. It is a figure which shows the structure of the information hold | maintained at the prefetch plan memory | storage part 124 shown in FIG. It is a figure which shows an example of the minimum look-ahead amount corresponding | compatible table 280. FIG. It is a figure which shows an example of the prefetch information 282. It is a figure which shows an example of the prefetch request | requirement 290. FIG. 3 is a diagram illustrating an internal configuration of hardware of a content reproduction device 60. FIG. It is a flowchart which shows the control structure of a main process. It is a flowchart which shows the detailed control structure of a content switching process. It is a flowchart which shows the control structure of a high-speed switching process. It is a flowchart which shows the control structure of a prefetch process. It is a figure which shows an example of a screen transition at the time of switching content. It is a figure which shows an example of a display of the size of a content, and the reading amount. It is a figure which shows an example of a screen transition at the time of high-speed switching. It is a figure which shows an example of the display of the size of content and the amount of reading at the time of high-speed switching. It is a figure which shows an example of the channel script in the case of handling a broadcast service and a mail service as a channel. It is a figure which shows an example of the composite media script containing the description which switches the medium reproduced | regenerated by the remaining amount of the area | region which can be temporarily stored.

Explanation of symbols

  52 communication network, 54 content server, 56 content list information server, 60 content playback device, 100 network communication unit, 102 channel list script storage unit, 104 channel list script analysis unit, 106 content list script acquisition unit, 108 content list script analysis 110, content list storage unit, 114 input unit, 116 content switching control unit, 118 timer, 120 content playback unit, 122 prefetch planning unit, 124 prefetch plan storage unit, 126 content prefetch unit, 128 content storage unit, 140 playback component Group, 142 composite media script acquisition unit, 144 composite media script analysis unit, 146 composite media playback schedule storage unit, 148 composite media 150A animation playback unit, 150B text playback unit, 150C still image playback unit, 150D video playback unit, 160 remote control, 360 input interface, 362 monitor, 364 speaker, 366 network interface, 368 CPU, 370 bus, 372 memory

Claims (6)

A content playback apparatus that acquires and plays back a plurality of contents provided by a predetermined provider,
List preparing means for preparing a list that defines an order among the plurality of contents provided by the predetermined provider;
Acquisition means for acquiring and holding the plurality of contents according to a predetermined acquisition order;
Reproduction means for switching and reproducing the plurality of contents acquired and held by the acquisition means according to an order determined by the list;
In response to the switching of the content to be played back by the playback means, based on the relationship between the order in the list of the content being played back by the playback means and the order in the list of the plurality of contents, Planning means for planning the acquisition order of the plurality of contents so as to acquire the contents before starting reproduction ;
Content selection means for selecting one of the contents determined by the list according to an operation by a user;
Frequency measuring means for measuring the frequency of selection of content by the content selecting means;
In response to the frequency measured by the frequency measuring means has reached a predetermined value, specific initiation of the content by switching the content specifying means, seen including a holding means for holding a predetermined time,
The reproducing means includes
In response to satisfying a predetermined condition, based on the list, a switching content specifying means for specifying content to be switched and played back,
Switching playback means for switching the content to be played back from the content being played back to the content specified by the switching content specifying means,
The switching content specifying means includes a means for specifying the content selected by the content selection means as content to be switched and played back. The list includes information defining an order of the plurality of contents, and summary information indicating an outline of each of the plurality of contents,
In response to the frequency measured by the frequency measurement means reaching a predetermined value, the means for holding the content is held for a predetermined time by the means for specifying for a predetermined time, and The content reproduction apparatus according to claim 1 , further comprising means for displaying the summary information about the content selected by the content selection means. In response to the frequency measured by the frequency measuring means reaching a predetermined value, the means for displaying suspends the specific start of the content by the specifying means for a predetermined time, The summary information about the content selected by the content selection unit and the summary information about the content in the list in which the difference in order between the content selected by the content selection unit is smaller than a certain value. The content reproduction apparatus according to claim 2 , comprising means for displaying. There are a plurality of lists, each of the plurality of lists corresponds to a predetermined channel, the channels have an order relationship with each other, and the list preparation means acquires the plurality of lists, and the list Channel order list holding means for holding according to the order relation of the corresponding channels,
The content reproduction apparatus further includes channel selection means for selecting a channel according to an operation by a user,
In response to selection of a channel by the channel selection unit, the switching content specifying unit selects a content to be switched and reproduced based on a list held in the channel order list holding unit corresponding to the selected channel. The content reproduction apparatus according to claim 1 , comprising means for specifying. The planning means, based on order relation channel corresponding to the order and the lists in the list of contents means specified for the specific, including means for determining the acquisition order, according to claim 4 Content playback device. The means for determining is included in a list having a small difference in order in the list with the content being played back by the playing means and a small difference in the order relationship with a channel corresponding to the list. The content reproduction apparatus according to claim 5 , further comprising: an adjacent channel order priority acquisition planning unit for determining the acquisition order so that the acquisition order is acquired sequentially.

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