[DESCRIPTION] [Title] RECEIVING DEVICE AND METHOD, TRANSMITTING DEVICE AND METHOD, AND PROGRAM [Technical Field] [0001] The present technique relates to receiving devices and methods, transmitting devices and methods, and programs, and particularly to a receiving device and method, transmitting device and method, and program that enable assured download reservation of AV content. [Bac]cground Art] [0002] In recent years, due to dissemination of digital broadcasting, reception of multiple channels or highdefinition television broadcasting has become general. [0003] Meanwhile, technique studying and system formulation for enabling not only normal television broadcasting but also more advanced broadcasting service required by viewers by utilizing the band that can be used in the digital broadcasting are being carried out. [0004] Functions required by viewers include on-demand viewing, which allows AV content to be viewed whenever a viewer M wants to view it. However, it is considered difficult to realize the on-demand viewing in not broadcasting of bidirectional transmission but broadcasting of unidirectional transmission. [0005] So, in order to enable the on-demand viewing in the broadcasting of unidirectional transmission, studies are being made on the NRT service in which broadcast AV content is temporarily recorded in a storage and thereafter reproduced thereof on the premise that the receiving device holds the high-capacity storage (refer to e.g. Patent Literature 1). [0006] The NRT (Non Real Time) service is not premised on viewing in real time. In this service, there is no need to view AV content in synchronization with the broadcast time of the AV content and AV content is transmitted as data by a broadcast signal. [0007] Specifically, in the-NRT service, completion of recording (download) in a shorter time is possible if tlife transmission band of a signal with a broadcast wave is wider for example, differently from conventional recording reservation of AV content of a broadcast show. Or, download is completed in a longer time if the 41 transmission band of a signal by a broadcast wave is narrower for example. [Citation List] [Patent Literature] [0008] [PTL 1] JP 2011-41242A [Siommary] [Technical Problems] [0009] In the conventional NRT service, in the case of reserving download of AV content, information that is called NRT-IT (NRT Information Table) and relates to download of AV content transmitted in non-real time needs to be acquired in advance. In the NRT-IT, a list of AV content for which download reservation is possible is described. From the list, desired AV content is selected. [0010] The NRT-IT is periodically transmitted together with AV content. However, if the NRT-IT held by the receiving device is old, even AV content for which download reservation is possible essentially cannot be reserved and the download reservation must be awaited until the NRT-IT is updated. As a result, possibly the opportunity for the download reservation of the AV content is lost. J^ [0011] The present technique is made in view of such circumstances and is to enable assured download reservation of AV content and widening of the opportunity for download reservation. [Solution to Problems] [0012] A receiving device of one aspect of the present technique includes a receiver that receives AV content, a detector that detects trigger information that is transmitted together with the AV content to be received and relates to control of an application program for being run in conjunction with the AV content, and an acquirer that acquires an application program for allowing selection of AV content for which download reservation is possible and that is transmitted in non-real time, based on the detected trigger information. The receiving device further includes a tentative reservation registering part that registers AV content selected based on the acquired application program as tentative reservation, and a definitive reservation registering part that registers the tentatively reserved AV content as definitive reservation if an identifier of AV content for which download reservation is possible, included in download information that is periodically transmitted together # with the AV content and relates to download of AV content transmitted in non-real time, is identical to an identifier of the tentatively reserved AV content. [0013] The tentative reservation registering part registers selected AV content as tentative reservation if the download information is not recorded. [0014] The application program is content for allowing selection of AV content for which download reservation is possible and that is transmitted in non-real time based on a list. [0015] The receiving device further includes a controller that controls acquisition or activation of the application program or stop of the application program that is running, in accordance with a command indicated by the detected trigger information. [0016] The receiving device may be an independent device or may be an internal bloclc configuring one device. [0017] A receiving method or a program of one aspect of the present technique is a method or a program corresponding to the above-described receiving device of one aspect of the present technique. [0018] In the receiving device and method and the program of one aspect of the present technique, AV content is received, and trigger information that is transmitted together with the AV content to be received and relates to control of an application program for being run in conjunction with the AV content is detected. Based on the detected trigger information, an application program for allowing selection of AV content for which download reservation is possible and that is transmitted in non-real time is acquired. Furthermore, AV content selected based on the acquired application program is registered as tentative reservation. In addition, the tentatively reserved AV content is registered as definitive reservation if the identifier of AV content for which download reservation is possible, included in download information that is periodically transmitted together with the AV content and relates to download of AV content transmitted in non-real time, is identical to the identifier of the tentatively reserved AV content. [0019] A transmitting device of one aspect of the present technique includes a trigger information generator that - generates trigger information relating to control of an application program run in conjunction with AV content in A a receiving device, a transmitter that transmits the generated trigger information together with the AV content, and a download information generator that generates download information relating to download of the AV content transmitted in non-real time. The transmitter periodically transmits the generated download information together with the AV content. [0020] At least one of commands to control acquisition or activation of an application program for allowing selection of AV content for which download reservation is possible and that is transmitted in non-real time or stop of the application program that is running is included in a command indicated by the trigger information. [0021] The transmitter multiplexes the trigger information into a transport stream corresponding to the AV content and transmits the trigger information. [0022] The transmitter stores the trigger information in an adaptation field of a packet configuring a transport stream corresponding to the AV content and transmits the trigger information. [0023] The transmitting device may be an independent device or ^H may be an internal block configuring one device. [0024] A transmitting method or a program of one aspect of the present technique is a method or a program corresponding to the above-described transmitting device of one aspect of the present technique. [0025] In the transmitting device and method and the program of one aspect of the present technique, trigger information relating to control of an application program run in conjunction with AV content in a receiving device is generated, and the generated trigger information is transmitted together with the AV content. Furthermore, download information relating to download of the AV content transmitted in non-real time is generated, and the generated download information is periodically transmitted together with the AV content. [Advantageous Effect of Invention] [0026] According to one aspect of the present technique, the opportunity for download reservation of AV content can be widened. [Brief Description of Drawings] [0027] [FIG. 1] ^ FIG. 1 is a diagram showing a configuration example of a broadcasting system. [FIG.' 2] FIG. 2 is a diagram showing, a configuration example of a broadcasting device. [FIG. 3] FIG. 3 is a diagram showing a configuration example of a receiving device. [FIG. 4] FIG. 4 is a diagram showing the protocol stack of a signal of a broadcast wave. [FIG. 5] FIG. 5 is a diagram showing a configuration example of NRT-IT. [FIG. 6] FIG. 6 is a state transition diagram of an application program. [FIG. 7] FIG. 7 is a diagram for explaining an example in which trigger information is multiplexed into a transport stream. [FIG. 8] FIG. 8 is a diagram showing a concept that trigger information is so transmitted as to be included in a PCR packet of TS. j0 10 [FIG. 9] FIG. 9 is a flowchart for explaining AV content transmission processing. [FIG. 10] FIG. 10 is a flowchart for explaining AV content reception processing. [FIG. 11] FIG. 11 is a flowchart for explaining the AV content reception processing. [FIG. 12] FIG. 12 is a diagram showing a configuration example of TDO content. [FIG. 13] FIG. 13 is a diagram showing a display example of a list of AV content permitted to be tentatively reserved. [FIG. 14] FIG. 14 is a diagram showing a configuration example of a computer. [Description of Embodiments] [0028] An embodiment of the present technique will.be described below with reference to the drawings. [0029] [Configuration of Broadcasting System] FIG. 1 is a diagram showing a configuration example of a # 11 broadcasting system. [0030] A broadcasting system 1 is composed of a broadcasting device 11, a receiving device 13, and a content delivery server 18. [0031] The broadcasting device 11 is set at a broadcasting station. The broadcasting device 11 transmits AV content of e.g. show, CM, etc. as a digital television broadcast signal. The digital television broadcast signal is transmitted as normal broadcasting and NRT broadcasting. [0032] The normal broadcasting is broadcasting premised on viewing in real time in the receiving device 13 into which this broadcast signal is received. Furthermore, the NRT broadcasting is not premised on viewing in real time. In the NRT broadcasting, there is no need to view AV content at the broadcast time of the AV content, and the AV content is transmitted as data by a broadcast signal. [0033] Furthermore, the broadcasting device 11 transmits trigger information as a command for ordering execution of data broadcasting content executed in association with the progression of AV content of a show, etc. in such a manner that the trigger information is included in the # 12 digital television broadcast signal. This trigger information includes, in addition to information indicating the kind of command, data broadcasting content, i.e. information indicating the acquisition source of the data broadcasting content, and so forth. Details of the trigger information will be described later. [0034] In addition, the broadcasting device 11 periodically transmits information relating to download of AV content transmitted in non-real time in the NRT broadcasting (hereinafter, referred to as download information) together with AV content. As the download information, e.g. the above-described NRT-IT is present. Details thereof will be described later. [0035] The digital television broadcast signal transmitted from the broadcasting-device 11 is received by the receiving device 13 by way of a relay station 12. [0036] The receiving device 13 is set at a user's house for example. If the receiving device 13 receives a digital television broadcast signal of the normal broadcasting, the receiving device 13 makes AV content obtained from the digital television broadcast signal be displayed on a display 13A and viewed. # 13 [0037] Furthermore, if download of AV content is reserved, the receiving device 13 starts reception of a digital television broadcast signal of the NRT broadcasting at the broadcast start time of the reserved AV content, and records the AV content obtained from the digital television broadcast signal in a storage 14. Moreover, the receiving device 13 reads out the AV content recorded in the storage 14 and reproduces it to thereby make the AV content broadcast by the NRT broadcasting be viewed. [0038] In addition, the receiving device 13 is connected to a LAN (Local Area Network) 15 and can connect to the Internet 17 via a router 16. If trigger information is obtained from a digital television broadcast signal, the receiving device 13 connects to the content delivery server 18 via the Internet 17 based on the acquisition source of data broadcasting content included in the trigger information and acquires the data broadcasting content. The data broadcasting content is not limited by the method of acquiring it via the Internet 17 and may be acquired from a multiplexed stream obtained by demodulating a digital television broadcast signal for example. [0039] 0 14 The receiving device 13 registers tentative reservation of AV content based on the acquired data broadcasting content and then registers definitive reservation of the tentatively reserved AV content based on the download information periodically transmitted from the broadcasting device 11. Details of download reservation by use of data broadcasting content (TDO content to be described later) will be described later. [0040] The content delivery server 18 is set at a broadcasting station or the like. The content delivery server 18 generates data broadcasting content for presenting a list of AV content for which download reservation is possible in.the NRT broadcasting. The content delivery server 18 delivers data broadcasting content via the Internet 17 in response to an acquisition request from the receiving device 13. • [0041] The broadcasting system 1 is configured in the abovedescribed manner. [0042] The data broadcasting content is realized through running of an application program supplied to the receiving device 13 by a computer in the receiving device 13. Therefore, hereinafter, the data broadcasting content 15 will be referred to also as data broadcasting application program or data broadcasting application. [0043] [Configuration of Broadcasting Device] FIG. 2 is a diagram showing a configuration example of a broadcasting device. [0044] The broadcasting device 11 is composed of a video encoder 31, an audio encoder 32, a multiplexer 33, a triggergenerator 34T a download information generator 35, and a sender 36. [0045] The video encoder 31 encodes the video stream of AV content of a show, etc. input from the previous stage in accordance with a predetermined encoding, system and supplies the encoded video stream obtained as the result to the multiplexer 33. Examples of the encoding system in the video encoder 31 include MPEG2 (Moving Picture Experts Group phase 2) system and H.264 system. [0046] The audio encoder 32 encodes the audio stream corresponding to the video stream input to the video encoder 31 in accordance with a predetermined encoding system and supplies the encoded audio stream obtained as the result to the multiplexer 33. Examples of the # 16 encoding system in the audio encoder 32 include AC3 (Audio Code number 3) system and AAC (Advanced Audio Coding) system. [0047] The trigger generator 34 generates trigger information in association with the progression of the video stream of AV content input from the previous stage and supplies it to the multiplexer 33. [0048] The download information generator 35 periodically generates download information such as NRT-IT based on information relating to AV content for which download reservation is possible, and supplies it to the multiplexer 33. [0049] To the multiplexer 33, the encoded video stream from the video encoder 31, the encoded audio stream from the audio encoder 32, the trigger information from the trigger generator 34, and the download information from the download information generator 35 are supplied. [0050] The multiplexer 33 multiplexes the encoded video stream and the encoded audio stream and multiplexes also' the trigger information to supply the multiplexed stream obtained as the result to the sender 36. Specifically, # 17 the multiplexer 33 multiplexes the streams into e.g. TS (transport stream). Alternatively, in consideration of network delivery of digital television broadcasting, the multiplexer 33 may multiplex the streams into the ISO base media file format (MP4) suitable for it. [0051] Furthermore, if the download information is supplied from the download information generator 35, the multiplexer 33 multiplexes the download information into the multiplexed stream. [0052] The sender 36 sends out the multiplexed stream supplied from the multiplexer 33 as a digital television broadcast signal. [0053] The broadcasting device 11 is configured in the abovedescribed manner. [0054] [Configuration of Receiving Device] FIG. 3 is a diagram showing a configuration example of the receiving device. [0055] The receiving device 13 is composed of a tuner 51, a demultiplexer 52, a video decoder 53, a video output part 54, an audio decoder 55, an audio output part 56, a # 18 trigger detector 57, a controller 58, a memory 59, an •operation part 60, a communication I/F 61, a cache memory 62, an application engine 63, a download information detector 64, and a download reservation unit 65. [0056] The tuner 51 receives and demodulates a digital television broadcast signal corresponding to the channel selected by the user and supplies the multiplexed stream obtained as the result to the demultiplexer 52. [0057] The demultiplexer 52 separates the multiplexed stream supplied from the tuner 51 and supplies the separated encoded video stream and encoded audio stream to the video decoder 53 and the audio decoder 55, respectively. Furthermore, if trigger information or download information transmitted together with the multiplexed stream is detected, the demultiplexer 52 supplies the trigger information and the download information to the trigger detector 57 and the download information detector 64, respectively. [0058] The video decoder 53 decodes the encoded video stream from the demultiplexer 52 and supplies the video signal obtained as the result to the video output part 54. [0059] 19 The video output part 54 outputs the video signal supplied from the video decoder 53 to the subsequent stage (e.g. display 13A}. Furthermore, the video output part 54 combines a video signal of a data broadcasting application program (hereinafter, referred to as data broadcasting application) supplied from the application engine 63 and the video signal supplied from the video decoder 53, and outputs the resulting signal to the subsequent stage. [0060] The audio decoder 55 decodes the encoded audio stream from the demultiplexer 52 and supplies the audio signal obtained as the result to the audio output part 55. [0061] The audio output part 56 outputs the audio signal supplied from the audio decoder 55 to the subsequent stage (e.g. spea]