Transmitting device and receiving device

Abstract

To provide a transmitting device and a receiving device that can increase the durability of reproduction of objects that make up content while reducing the processing load on the receiving device.SOLUTION: A transmitting device includes a control unit that assigns a first packet of a first object having a first resolution to a first transmission path and assigns a second packet of a second object having a second resolution to a second transmission path, as packets of objects that make up content, and a transmitting unit that transmits the first packet to a receiving device via the first transmission path and transmits the second packet to the receiving device via the second transmission path.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a transmitting device and a receiving device. [Background technology]

[0002] The 12 GHz band is used for satellite digital broadcasting, including 4K / 8K high-definition services, and this type of satellite digital broadcasting transmission method is called ISDB-S3. Furthermore, the use of the 21 GHz band for next-generation satellite digital broadcasting is attracting attention.

[0003] Under these circumstances, as an example of a large-capacity transmission technology, a technology has been proposed in which content is divided and the divided content is assigned to separate transmission paths for transmission (for example, Patent Document 1). Such a transmission method may be called a bulk transmission method.

[0004] Also, a technique has been proposed in which packets of objects with different resolutions are transmitted from a transmitting device to a receiving device as data of the objects that make up the content, and the receiving device plays back only the objects with the selected resolution and discards packets of objects with other resolutions (for example, Patent Document 2). Such a transmission method may be called a packet filter method. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-133612 [Patent Document 2] Japanese Patent Publication No. 2022-032838 Summary of the Invention [Problem to be solved by the invention]

[0006] The packet filter method described above is excellent in terms of reducing the processing load on the receiving device, but if part of an object constituting the content is missing, the receiving device may not be able to play back the missing part of the object. Also, with the bulk transmission method described above, it is possible that one of the multiple transmission paths may become unavailable during content transmission.

[0007] Therefore, the present invention has been made to solve the above-mentioned problems, and aims to provide a transmitting device and a receiving device that can increase the tolerance for playback of objects that make up content while reducing the processing load on the receiving device. [Means for solving the problem]

[0008] The disclosed aspect is a transmitting device comprising: a control unit that assigns a first packet of a first object having a first resolution to a first transmission path and a second packet of a second object having a second resolution to a second transmission path as packets of objects that constitute content; and a transmitting unit that transmits the first packet to a receiving device via the first transmission path and transmits the second packet to the receiving device via the second transmission path.

[0009] The disclosed aspect is a receiving device comprising: a receiving unit that receives a first packet of a first object having a first resolution via a first transmission path as packets of objects constituting content, and receives a second packet of a second object having a second resolution via a second transmission path; and a control unit that, when the first transmission path is selected, complements the missing first packet with the second packet corresponding to the missing first packet if the first packet is missing. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a transmitting device and a receiving device that can increase the durability of playback of objects that make up content while reducing the processing load on the receiving device. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing a transmission system 10 according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating a transmission device 100 according to the embodiment. [Figure 3] FIG. 3 is a diagram showing a packet configuration according to the embodiment. [Figure 4] FIG. 4 is a diagram showing divided frames according to the embodiment. [Figure 5] FIG. 5 is a diagram showing a receiving device 200 according to the embodiment. [Figure 6] FIG. 6 is a diagram for explaining an operation example according to the embodiment. [Figure 7] FIG. 7 is a diagram for explaining an operation example according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Next, an embodiment of the present invention will be described. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and the dimensional ratios may differ from those of the actual parts.

[0013] Therefore, specific dimensions should be determined with reference to the following explanation. Of course, the dimensional relationships and ratios may differ between the drawings.

[0014] [Disclosure Summary] A transmitting device according to the disclosure outline includes a control unit that assigns a first packet of a first object having a first resolution to a first transmission path and a second packet of a second object having a second resolution to a second transmission path as packets of objects constituting content, and a transmitting unit that transmits the first packet to a receiving device via the first transmission path and transmits the second packet to the receiving device via the second transmission path.

[0015] A receiving device according to the disclosure summary includes a receiving unit that receives a first packet of a first object having a first resolution via a first transmission path as packets of objects constituting content, and receives a second packet of a second object having a second resolution via a second transmission path, and a control unit that, when the first transmission path is selected, complements the missing first packet with the second packet corresponding to the missing first packet if the first packet is missing.

[0016] In the outline of the disclosure, a transmitting device transmits a first packet to a receiving device via a first transmission path, and transmits a second packet via a second transmission path. The receiving device complements a missing first packet with a second packet corresponding to the missing first packet. This configuration can reduce the processing load of the receiving device using a packet filter method while increasing the tolerance for playback of objects that make up the content.

[0017] [Embodiment] (Transmission System) A transmission system according to an embodiment will be described below. Fig. 1 is a diagram showing a transmission system 10 according to an embodiment. As shown in Fig. 1, the transmission system 10 includes a content streamer 100X, a transmitting device 100, a receiving device 200, and a content decoder 200X.

[0018] The content streamer 100X distributes content including objects. The objects may include 3D objects generated by a 3D model. The content may comply with 3DoF+ (Degree of Freedom), which involves viewpoint movement within the range of a user's head movement while sitting, or 6DoF, which involves viewpoint movement within the range of a user's free movement. The content may include audio objects.

[0019] In an embodiment, the content streamer 100X may distribute 3D objects having different resolutions. For example, the content streamer 100X may distribute a first object having a first resolution and a second object having a second resolution as 3D objects constituting the content. The first resolution may be higher than the second resolution.

[0020] In the following, an example will be given in which the content includes a first object having a first resolution, a second object having a second resolution, and an audio object. Note that the first object and the second object are the same object except for the difference in resolution.

[0021] The content streamer 100X may distribute the content to the transmitting device 100 by transmission using satellite broadcasting, transmission using the Internet network, transmission using mobile communication, or the like.

[0022] The transmitting device 100 transmits content acquired from the content streamer 100X to the receiving device 200. Here, the transmitting device 100 may transmit the content to the receiving device 200 using two or more transmission paths. The two or more transmission paths may include a 21 GHz band satellite transmission path, a 12 GHz band satellite transmission path, an IP line, etc. Details of the transmitting device 100 will be described later (see FIG. 2).

[0023] The receiving device 200 receives content from the transmitting device 100. Here, the receiving device 200 may receive content from the transmitting device 100 using two or more transmission paths. The two or more transmission paths may include a 21 GHz band satellite transmission path, a 12 GHz band satellite transmission path, an IP line, etc. Details of the receiving device 200 will be described later (see FIG. 5).

[0024] The content decoder 200X decodes the data output from the receiving device 200 and plays back the content based on the decoded data. Although not particularly limited, the content decoder 200X may include a terminal such as a smartphone or a tablet.

[0025] The transmission between the content streamer 100X and the transmitting device 100 may be in the form of an IP packet. The IP packet includes object identification information (hereinafter referred to as object ID) at a predetermined position. The predetermined position is agreed upon in advance between the content streamer 100X and the transmitting device 100. The object ID is an ID that identifies the first object, the second object, and the audio object.

[0026] A specific method may be adopted for transmission between the transmitting device 100 and the receiving device 200. The specific method is ISDB-S3 (Integrated Services Digital Broadcasting for Satellite, 3 rd The specified method may include the MMT (MPEG Media Transport) standard conforming to ARIB STD-B60. MMT may be read as ISO / IEC 23008-1. The specified method may include the MMTP (MMT Protocol) standard conforming to MMT.

[0027] (Transmitting device) The transmitting device 100 according to the embodiment will be described below. Fig. 2 is a diagram showing the transmitting device 100 according to the embodiment.

[0028] As shown in FIG. 2, the transmission device 100 includes an acquisition unit 110, a designation unit 120, a TLV signal generation unit 130, a generation unit 140, a transmitter 150, and an encapsulation unit 160.

[0029] The acquisition unit 110 acquires content from the content streamer 100X. As described above, the content may include 3D objects. The 3D objects included in the content may include a first object having a first resolution and a second object having a second resolution.

[0030] The designation unit 120 designates transmission paths for the first object, the second object, and the audio object. Specifically, the designation unit 120 identifies an object ID included in a predetermined position of an IP packet constituting the content acquired by the acquisition unit 110, and identifies the IP packet of the first object, the IP packet of the second object, and the IP packet of the audio object based on the identified object ID. The designation unit 120 assigns the IP packet of the first object to a 21 GHz band satellite transmission path, assigns the IP packet of the second object to a 12 GHz band satellite transmission path, and assigns the IP packet of the audio object to an IP line.

[0031] The TLV signal generator 130 generates a TLV signal by converting IP packets into TLV packets. The TLV signal generator 130 converts an IP packet of a first object into a TLV packet of the first object, an IP packet of a second object into a TLV packet of the second object, and an IP packet of an audio object into a TLV packet of the audio object.

[0032] For example, as shown in Figure 3, an MMTP packet is composed of an MMTP header and an MMTP payload. Although not particularly limited, an MMTP packet may include a presentation time stamp (PTS) of an object corresponding to the MMTP packet (and thus to an IP packet or a TLV packet). The PTS may be included in the MMTP payload as control information.

[0033] An IP packet includes an IP header, a UDP header, and an IP packet payload. The IP packet payload includes one or more MMTP packets. The IP packet may include an object ID. The object ID may be included in a predetermined position in the IP packet payload as control information.

[0034] A TLV packet includes a TLV header and a TLV packet payload. The TLV packet includes fields such as 0x7F, Type, and Length. 0x7F may be a field that identifies the start position of the TLV packet. Type is a field that identifies the type of the IP packet included in the TLV packet, such as whether the IP packet included in the TLV packet is IPv4, IPv6, or a header-compressed IP packet. Possible values ​​for Type may include undefined (Reserved) values ​​such as 0x04-0xFD. Although not particularly limited, 0x7F and Type may be referred to as a packet field type. The TLV packet payload includes one or more IP packets.

[0035] The generation unit 140 generates a frame segment for each transmission path based on the sequence of the TLV packets for each transmission path. Each frame segment for each transmission path is made up of one or more slot segments.

[0036] Specifically, as shown in Fig. 4, the generation unit 140 generates a divided frame (divided slot #1 in Fig. 4) for a 12 GHz band satellite transmission channel based on the TLV packet of the second object. The divided frame and / or divided slot for the 12 GHz band satellite transmission channel may include one or more TLV packets of the second object.

[0037] The generation unit 140 generates divided frames (divided slots #2 to #N-1 in FIG. 4) for the 21 GHz band satellite transmission channel based on the TLV packet of the first object. The divided frame and / or divided slot for the 21 GHz band satellite transmission channel may include one or more TLV packets of the first object.

[0038] The generation unit 140 generates a segmented frame (segmented slot #N in FIG. 4) for an IP line based on the TLV packet of the audio object. The segmented frame and / or segmented slot for an IP line may include one or more TLV packets of audio objects.

[0039] Here, the 21 GHz band satellite transmission channel is a higher bandwidth than the 12 GHz band satellite transmission channel. The bandwidth available for the 21 GHz band satellite transmission channel may be a wider bandwidth (600 MHz) than the bandwidth available for the 12 GHz band satellite transmission channel (500 MHz). Therefore, the number of divided slots constituting a divided frame for the 21 GHz band satellite transmission channel may be greater than the number of divided slots constituting a divided frame for the 12 GHz band satellite transmission channel. For example, the number of divided slots constituting a divided frame is determined by the ratio between the maximum bit rate of the 21 GHz band satellite transmission channel and the maximum bit rate of the 12 GHz band satellite transmission channel.

[0040] For example, the generation unit 140 may specify the maximum bit rate of the 21 GHz band satellite transmission channel based on TMCC (Transmission and Multiplexing Configuration Control) information 1 for the 21 GHz band satellite transmission channel. The TMCC information 1 may be acquired from the transmitter 150A. Similarly, the generation unit 140 may specify the maximum bit rate of the 12 GHz band satellite transmission channel based on TMCC information 2 for the 12 GHz band satellite transmission channel. The TMCC information 2 may be acquired from the transmitter 150B. The maximum bit rate is specified based on the modulation method and coding rate (e.g., a low-density parity-check code (LDPC) coding rate) of each transmission channel, and the modulation method and coding rate can be specified based on the TMCC information. Note that if the maximum bit rate of each transmission channel is constant or known, the generation unit 140 may omit acquiring the TMCC information.

[0041] For example, the generating unit 140 outputs information about slots constituting the divided frame for each transmission path (hereinafter referred to as slot information) to the transmitter 150. The slot information may include information indicating the number of slots constituting the divided frame for each transmission path, or may include information indicating the ratio of the maximum bit rates of the respective transmission paths. Note that if the maximum bit rates of the respective transmission paths are constant or known, the generating unit 140 may omit outputting the slot information.

[0042] As shown in Figure 4, each frame segment may have a fixed length. Therefore, if there is a shortage of TLV packets in a frame segment, a fixed-length frame segment may be generated by inserting a NULL packet. Note that the TLV packet of the first object may be allocated so as to span the frame segments for the 21 GHz band satellite transmission path.

[0043] The header of the TLV packet located at the beginning of each frame segment may be referred to as the first TLV header. The first TLV header may include information identifying whether the TLV packet is the TLV packet located at the beginning of the frame segment. For example, such information may be included in the Type included in the TLV header. In such a case, an undefined (Reserved) value such as 0x04-0xFD may be used from among the possible values ​​of Type.

[0044] The generation unit 140 outputs the frame segments for the 21 GHz band satellite transmission channel to the transmitter 150A, outputs the frame segments for the 12 GHz band satellite transmission channel to the transmitter 150B, and outputs the frame segments for the IP line to the encapsulation unit 160.

[0045] The transmitter 150 transmits the divided frames generated by the generation unit 140. In the embodiment, transmitter 150 is exemplified by transmitter 150A and transmitter 150B. Specifically, the transmitter 150A transmits the divided frames for a 21 GHz band satellite transmission channel (i.e., the TLV packet of the first object) via a 21 GHz band satellite transmission channel. The transmitter 150A may include a satellite antenna or may be connected to the satellite antenna. The transmitter 150B transmits the divided frames for a 12 GHz band satellite transmission channel (i.e., the TLV packet of the second object) via a 12 GHz band satellite transmission channel. The transmitter 150B may include a satellite antenna or may be connected to the satellite antenna.

[0046] The encapsulation unit 160 transmits the frame segments generated by the generation unit 140. Specifically, the encapsulation unit 160 encapsulates the frame segments for the IP line by adding an IP header, and transmits the encapsulated IP packets (i.e., TLV packets of the audio object) via the IP line.

[0047] In an embodiment, the designation unit 120 may be configured as a control unit that assigns, as packets of objects constituting the content, a first packet of a first object having a first resolution to a first transmission path, and a second packet of a second object having a second resolution to a second transmission path.

[0048] In the embodiment, the 21 GHz band satellite transmission path is an example of a first transmission path, and the 12 GHz band satellite transmission path is an example of a second transmission path.

[0049] In an embodiment, at least one of an MMTP packet, an IP packet, and a TLV packet of a first object is an example of a first packet, and at least one of an MMTP packet, an IP packet, and a TLV packet of a second object is an example of a second packet.

[0050] In the embodiment, the transmitter 150 may constitute a transmitting unit that transmits a first packet to the receiving device 200 via a first transmission path and transmits a second packet to the receiving device 200 via a second transmission path.

[0051] In an embodiment, the acquisition unit 110 may constitute an acquisition unit that acquires content.

[0052] (receiving device) The following describes the receiving device 200 according to the embodiment. Fig. 5 is a diagram showing the transmitting device 100 according to the embodiment.

[0053] As shown in FIG. 5, the receiving device 200 includes a receiver 210, a decapsulation unit 220, a reconstruction unit 230, a restoration unit 240, a culling unit 260, a selection unit 270, a filter unit 280, and an output unit 290.

[0054] The receiver 210 receives the frame segments from the transmitting device 100. In the embodiment, receivers 210A and 210B are exemplified as the receivers 210. Specifically, the receiver 210A receives the frame segments for the 21 GHz band satellite transmission channel (i.e., the TLV packet of the first object) via the 21 GHz band satellite transmission channel. The receiver 210A may include a satellite antenna or may be connected to the satellite antenna. The receiver 210B receives the frame segments for the 12 GHz band satellite transmission channel (i.e., the TLV packet of the second object) via the 12 GHz band satellite transmission channel. The receiver 210B may include a satellite antenna or may be connected to the satellite antenna.

[0055] The decapsulating unit 220 receives the frame segments from the transmitting device 100. Specifically, the decapsulating unit 220 receives IP packets (i.e., TLV packets of audio objects) via an IP line, decapsulates the IP packets by removing the IP headers, and outputs the frame segments for the IP line.

[0056] The reconstruction unit 230 reconstructs a sequence of TLV packets for each transmission path based on the frame segments for each transmission path in the reverse procedure of the generation unit 140. The frame segments for each transmission path are made up of one or more slot segments.

[0057] Specifically, the reconstructing unit 230 reconstructs a sequence of TLV packets for each transmission channel. The reconstructing unit 230 reconstructs a sequence of TLV packets of the second object based on the segmented frame for the 12 GHz band satellite transmission channel (segmented slot #1 in FIG. 4). The reconstructing unit 230 reconstructs a sequence of TLV packets of the first object based on the segmented frame for the 21 GHz band satellite transmission channel (segmented slot #2 to segmented slot #N-1 in FIG. 4). The reconstructing unit 230 reconstructs a sequence of TLV packets of the audio object based on the segmented frame for the IP line (segmented slot #N in FIG. 4).

[0058] As described above, the 21 GHz band satellite transmission channel is a higher bandwidth than the 12 GHz band satellite transmission channel. The bandwidth available for the 21 GHz band satellite transmission channel may be a wider bandwidth (600 MHz) than the bandwidth available for the 12 GHz band satellite transmission channel (500 MHz). Therefore, the number of divided slots constituting a divided frame for the 21 GHz band satellite transmission channel may be greater than the number of divided slots constituting a divided frame for the 12 GHz band satellite transmission channel. For example, the number of divided slots constituting a divided frame is determined by the ratio between the maximum bit rate of the 21 GHz band satellite transmission channel and the maximum bit rate of the 12 GHz band satellite transmission channel.

[0059] For example, the reconstructing unit 230 may specify the maximum bit rate of the 21 GHz band satellite transmission channel based on TMCC information 1 for the 21 GHz band satellite transmission channel. The TMCC information 1 may be acquired from the receiver 210A. Similarly, the reconstructing unit 230 may specify the maximum bit rate of the 12 GHz band satellite transmission channel based on TMCC information 2 for the 12 GHz band satellite transmission channel. The TMCC information 2 may be acquired from the receiver 210B. The maximum bit rate is specified based on the modulation method and coding rate (e.g., LDPC coding rate) of each transmission channel, and the modulation method and coding rate can be specified based on the TMCC information. Note that if the maximum bit rate of each transmission channel is constant or known, the reconstructing unit 230 may omit acquiring the TMCC information.

[0060] For example, the reconstructing unit 230 acquires information about slots constituting the divided frame for each transmission path (hereinafter, slot information) from the receiver 210. The slot information may include information indicating the number of slots constituting the divided frame for each transmission path, or may include information indicating the ratio of the maximum bit rates of each transmission path. Note that if the maximum bit rates of each transmission path are constant or known, the reconstructing unit 230 may omit acquiring the slot information.

[0061] If the frame segment includes a NULL packet, the reconstruction unit 230 removes the NULL packet.

[0062] When a TLV packet is lost on one transmission path, the restoration unit 240 complements the missing TLV packet based on a TLV packet received correctly on another transmission path. The TLV packet received correctly on another transmission path is a TLV packet (hereinafter referred to as a complement TLV packet) corresponding to the TLV packet lost on one transmission path. The following options are available for identifying the complement TLV packet:

[0063] In option 1, a case may be assumed in which the difference between the delay of the 21 GHz band satellite transmission path and the delay of the 12 GHz band satellite transmission path is smaller than a threshold value. In other words, a case may be assumed in which a frame segment received via a 21 GHz band satellite transmission path is synchronized with a frame segment received via a 12 GHz band satellite transmission path. In such a case, the restoration unit 240 identifies a frame segment including a TLV packet that is normally received in one transmission path at a timing synchronized with a frame segment including a TLV packet that is missing in another transmission path. The restoration unit 240 may identify a TLV packet included in the identified frame segment as a complementary TLV packet. In option 1, the following options may be assumed as a method for complementing a missing TLV packet.

[0064] In option 1-1, the restoration unit 240 may complement the missing TLV packets in units of segmented frames. In such a case, the restoration unit 240 may identify segmented frames including the complemented TLV packets without specifically identifying the complemented TLV packets.

[0065] In option 1-2, the restoration unit 240 may complement missing TLV packets on a TLV packet-by-TLV packet basis. In such a case, the restoration unit 240 may identify the order of the missing TLV packets in the divided frame, and identify the TLV packets having the order closest to the identified order as the complementing TLV packets. Note that the order of the TLV packets is converted into an order according to the ratio between the maximum bit rate of the 21 GHz band satellite transmission channel and the maximum bit rate of the 12 GHz band satellite transmission channel.

[0066] In option 2, it is not necessary to assume that the difference between the delay of the 21 GHz band satellite transmission path and the delay of the 12 GHz band satellite transmission path is smaller than the threshold value. In other words, it is not necessary to assume that the divided frame received via the 21 GHz band satellite transmission path and the divided frame received via the 12 GHz band satellite transmission path are synchronized. In such a case, the restoration unit 240 may identify the playback time stamp (PTS) of the 3D object corresponding to the TLV packet missing in one transmission path, and identify the TLV packet having the PTS closest to the identified PTS as the complementary TLV packet. Note that the PTS may be included in the MMTP packet included in the TLV packet.

[0067] The culling unit 260 acquires viewpoint information from the content decoder 200X. The viewpoint information may include information indicating the line of sight of the user viewing the content, or may include information indicating the viewpoint position of the user viewing the content. The viewpoint information may be detected by various sensors provided in the content decoder 200X (a terminal having the content decoder 200X). The various sensors may include a gyro sensor, an acceleration sensor, and the like. Based on the viewpoint information, the culling unit 260 determines whether the 3D object is within or outside the user's field of view.

[0068] The selection unit 270 selects the resolution of the 3D object based on the determination result of the culling unit 260. For example, the selection unit 270 may select a first resolution (i.e., a first object) when it is determined that the 3D object is within the user's field of view, and may select a second resolution (i.e., a second object) when it is determined that the 3D object is outside the user's field of view.

[0069] The filter unit 280 extracts TLV packets of the resolution selected by the selector 270 and discards TLV packets of the resolution not selected by the selector 270. For example, when a first resolution is selected, the filter unit 280 extracts TLV packets of a first object. When a second resolution is selected, the filter unit 280 extracts TLV packets of a second object.

[0070] Here, it should be noted that in the case where the missing packets are complemented by the restoration unit 240, even if the first resolution is selected, the TLV packets of the second object may be extracted. Similarly, it should be noted that even if the second resolution is selected, the TLV packets of the first object may be extracted.

[0071] The output unit 290 outputs the TLV packets extracted by the filter unit 280 to the content decoder 200X. The content decoder 200X decodes the TLV packets output from the output unit 290, thereby decoding the content.

[0072] In an embodiment, the receiver 210 includes a receiving unit that receives, as packets of objects constituting the content, a first packet of a first object having a first resolution via a first transmission path, and receives a second packet of a second object having a second resolution via a second transmission path.

[0073] In the embodiment, the 21 GHz band satellite transmission path is an example of a first transmission path, and the 12 GHz band satellite transmission path is an example of a second transmission path.

[0074] In an embodiment, at least one of an MMTP packet, an IP packet, and a TLV packet of a first object is an example of a first packet, and at least one of an MMTP packet, an IP packet, and a TLV packet of a second object is an example of a second packet.

[0075] In the embodiment, when the first transmission path is selected, the restoration unit 240 and the filter unit 280 constitute a control unit that, when a first packet is lost, complements the lost first packet with a second packet corresponding to the lost first packet.

[0076] (Example of operation) An operation example of the embodiment will be described below. Figures 6 and 7 are diagrams showing an operation example of the embodiment. In the following, a TLV packet of a first object is represented by X, a TLV packet of a second object is represented by Y, and a TLV packet of an audio object is represented by Z. In the operation example, a case where a TLV packet (X) of a first object is lost will be illustrated.

[0077] First, an example of the operation of the transmission device 100 will be described with reference to FIG.

[0078] As shown in Fig. 6, the transmitting device 100 identifies the TLV packets of the first object, the second object, and the audio object based on the object ID included in the IP packet. The transmitting device 100 transmits fragmented frames (X1, X2, X3, ...) consisting of the TLV packets of the first object via a 21 GHz band satellite transmission path. The transmitting device 100 transmits fragmented frames (Y1, Y2, Y3, ...) consisting of the TLV packets of the second object via a 12 GHz band satellite transmission path. The transmitting device 100 transmits IP packets (Z1, Z2, Z3, ...) consisting of the TLV packets of the audio object via an IP line.

[0079] Secondly, an example of the operation of the receiving device 200 will be described with reference to Fig. 7. Here, a case where TLV packets (X2, X3, X4) are lost in a 21 GHz band satellite transmission path will be illustrated. Also, a case where a first resolution (i.e., a first object) is selected based on user viewpoint information will be illustrated.

[0080] As shown in Fig. 7, the receiving device 200 receives fragmented frames (X1, X2, X3, ...) consisting of TLV packets of a first object via a 21 GHz band satellite transmission path. The receiving device 200 receives fragmented frames (Y1, Y2, Y3, ...) consisting of TLV packets of a second object via a 12 GHz band satellite transmission path. The receiving device 200 receives IP packets (Z1, Z2, Z3, ...) consisting of TLV packets of an audio object via an IP line.

[0081] Here, since the TLV packets (X2, X3, X4) are lost in the 21 GHz band satellite transmission path, the receiving device 200 complements the lost TLV packets (X2, X3, X4) with the TLV packets (Y2, Y3, Y4) that are received normally in the 12 GHz band satellite transmission path. Therefore, the receiving device 200 outputs the TLV packet sequence (X1, Y2, Y3, Y4, X5, ...) to the filter unit 280 as the TLV packets corresponding to the 21 GHz band satellite transmission path.

[0082] In such a case, reception device 200 may replace the object ID of the complemented TLV packet (Y2, Y3, Y4) with the object ID of the first object. By such replacement, malfunction of filter unit 280 can be suppressed.

[0083] Note that the receiving device 200 outputs a sequence of TLV packets (Y1, Y2, Y3, Y4, Y5, ...) as a TLV packet corresponding to the 12 GHz band satellite transmission path to the filter unit 280 as usual. Similarly, the receiving device 200 outputs a sequence of TLV packets (Z1, Z2, Z3, Z4, Z5, ...) as a TLV packet corresponding to the IP line to the filter unit 280 as usual.

[0084] Furthermore, to illustrate a case where the first resolution (i.e., the first object) is selected based on the user's viewpoint information, the receiving device 200 extracts the sequence of TLV packets (X1, Y2, Y3, Y4, X5, . . .) corresponding to the 21 GHz band satellite transmission channel and discards the sequence of TLV packets (Y1, Y2, Y3, Y4, Y5, . . .) corresponding to the 12 GHz band satellite transmission channel. That is, the receiving device 200 outputs the sequence of TLV packets (X1, Y2, Y3, Y4, X5, . . .) corresponding to the 21 GHz band satellite transmission channel to the content decoder 200X.

[0085] (Action and effect) In the embodiment, the transmitting device 100 transmits a first packet to the receiving device 200 via a first transmission path (e.g., a 21 GHz band satellite transmission path) and transmits a second packet to the receiving device via a second transmission path (e.g., a 12 GHz band satellite transmission path). The receiving device complements a missing first packet with a second packet corresponding to the missing first packet. This configuration can reduce the processing load on the receiving device using a packet filter method while increasing the tolerance for playback of objects that make up the content. In particular, although it is expected that the resolution of the object will be reduced, it is possible to prevent complete loss of the object.

[0086] In the embodiment, the transmitting device 100 assigns a first packet, to which information (e.g., PTS) of the playback time of a first object based on the first packet is assigned, to a first transmission path, and assigns a second packet, to which information (e.g., PTS) of the second object based on the second packet is assigned, to a second transmission path. The receiving device 200 identifies the second packet corresponding to the missing first packet based on the playback time information assigned to the first packet and the second packet. With this configuration, the missing first packet can be appropriately complemented even when the first transmission path and the second transmission path are not synchronized.

[0087] [Other embodiments] Although the present invention has been described by the above disclosure, the descriptions and drawings that form part of this disclosure should not be understood as limiting the present invention. From this disclosure, various alternative embodiments, examples, and operating techniques will become apparent to those skilled in the art.

[0088] In the above disclosure, a case where the first transmission path is a 21 GHz band satellite transmission path and the second transmission path is a 12 GHz band satellite transmission path has been exemplified. However, the above disclosure is not limited to this. The first transmission path may be a 12 GHz band satellite transmission path and the second transmission path may be a 21 GHz band satellite transmission path. In such a case, a packet lost in the 12 GHz band satellite transmission path may be complemented by a packet normally received in the 21 GHz band satellite transmission path.

[0089] In the above disclosure, a case where the transmission paths of a 3D object are two transmission paths (a 21 GHz band satellite transmission path and a 12 GHz band satellite transmission path) has been exemplified. However, the above disclosure is not limited to this. The transmission paths of a 3D object may be three or more.

[0090] In the above disclosure, the first object and the second object are 3D objects. However, the above disclosure is not limited to this. The first object and the second object may be images having different resolutions.

[0091] Although not specifically mentioned in the above disclosure, content distributed from the content streamer 100X may include two or more types of objects. Even in such a case, each of the two or more types of objects may include an object having a different resolution. Various objects may be identified by information (e.g., object identification information) different from the above-mentioned object ID. The object identification information may be included as control information in the payload of an IP packet. The object identification information may be included as control information in the payload of an MMTP packet. For example, some objects may be within the field of view of a user viewing the content, while other objects may be outside the field of view of the user viewing the content.

[0092] Although not specifically mentioned in the above disclosure, the above disclosure may be applied to a 3D object displayed in VR (Virtual Reality). In such a case, the content distributed from the content streamer 100X may include a 360-degree video.

[0093] Although not specifically mentioned in the above disclosure, the content may be applied to a 3D object displayed in AR (Augmented Reality). In such a case, the background image of the 3D object may be an image captured by a camera provided in the content decoder 200X (a terminal having the content decoder 200X).

[0094] Although not specifically mentioned in the above disclosure, the receiving device 200 may be a home gateway.

[0095] In the above disclosure, a case where missing TLV packets are complemented in units of divided frames or units of TLV packets has been exemplified. However, the above disclosure is not limited to this. For example, missing TLV packets may be complemented in units of GOPs (Group of Pictures).

[0096] In the above disclosure, the transmission system 10 may employ SISO (Single-Input Single-Output) or MIMO (Multiple-Input Multiple-Output). As the MIMO, TDD-SVD-MIMO (Time Division Duplex-Singular Value Decomposition-Multiple-Input Multiple-Output) may be employed.

[0097] Although not specifically mentioned in the above disclosure, a program may be provided that causes a computer to execute each process performed by the transmitting device 100 and the receiving device 200. The program may also be recorded on a computer-readable medium. Using the computer-readable medium, the program can be installed on a computer. Here, the computer-readable medium on which the program is recorded may be a non-transitory recording medium. The non-transitory recording medium is not particularly limited, and may be, for example, a recording medium such as a CD-ROM or a DVD-ROM.

[0098] Alternatively, a chip may be provided that is configured by a memory that stores programs for executing the processes performed by the transmitting device 100 and the receiving device 200 and a processor that executes the programs stored in the memory.

[0099] (Addendum) The above disclosure may be expressed as follows:

[0100] A first feature is a transmitting device including: a control unit that assigns, as packets of objects that constitute content, a first packet of a first object having a first resolution to a first transmission path and a second packet of a second object having a second resolution to a second transmission path; and a transmitting unit that transmits the first packet to a receiving device via the first transmission path and transmits the second packet to the receiving device via the second transmission path.

[0101] A second feature is the transmitting device of the first feature, wherein the control unit assigns the first packet, to which information of a playback time of the first object based on the first packet is assigned, to the first transmission path, and assigns the second packet, to which information of a playback time of the second object based on the second packet is assigned, to the second transmission path.

[0102] A third feature is a transmitting device according to the first or second feature, further comprising an acquisition unit that acquires the content, and the control unit identifies the first packet and the second packet from the content acquired by the acquisition unit based on identification information of the object that can identify the resolution of the object.

[0103] A fourth feature is a transmitting device according to any one of the first to third features, wherein the frequency band of the first transmission path is higher than the frequency band of the second transmission path, and the first resolution is higher than the second resolution.

[0104] A fifth feature is a receiving device including: a receiving unit that receives, as packets of objects constituting content, a first packet of a first object having a first resolution via a first transmission path, and receives a second packet of a second object having a second resolution via a second transmission path; and a control unit that, when the first transmission path is selected, complements the missing first packet with the second packet corresponding to the missing first packet, if the first packet is missing.

[0105] A sixth feature is the receiving device of the fifth feature, wherein playback time information for the first object based on the first packet is assigned to the first packet, playback time information for the second object based on the second packet is assigned to the second packet, and the control unit identifies the second packet corresponding to the missing first packet based on the playback time information assigned to the first packet and the second packet.

[0106] A seventh feature is the receiving device according to the fifth or sixth feature, wherein the frequency band of the first transmission path is higher than the frequency band of the second transmission path, and the first resolution is higher than the second resolution. [Explanation of symbols]

[0107] 10: Transmission system, 100: Transmitting device, 100X: Content streamer, 110: Acquiring unit, 120: Specifying unit, 130: Signal generating unit, 140: Generating unit, 150: Transmitter, 150A: Transmitter, 150B: Transmitter, 160: Encapsulating unit, 200: Receiving device, 200X: Content decoder, 210: Receiver, 210A: Receiver, 210B: Receiver, 220: Decapsulating unit, 230: Reconstructing unit, 240: Restoring unit, 260: Culling unit, 270: Selecting unit, 280: Filtering unit, 290: Output unit

Claims

1. a control unit that allocates, as packets of objects constituting the content, a first packet of a first object having a first resolution to a first transmission path and a second packet of a second object having a second resolution to a second transmission path; a transmitting unit that transmits the first packet to the receiving device via the first transmission path and transmits the second packet to the receiving device via the second transmission path.

2. 2. The transmitting device according to claim 1, wherein the control unit assigns the first packet, to which information on the playback time of the first object based on the first packet is assigned, to the first transmission path, and assigns the second packet, to which information on the playback time of the second object based on the second packet is assigned, to the second transmission path.

3. an acquisition unit that acquires the content, The transmitting device according to claim 1 , wherein the control unit identifies the first packet and the second packet from the content acquired by the acquisition unit based on identification information of the object that can specify a resolution of the object.

4. the frequency band of the first transmission path is higher than the frequency band of the second transmission path; The transmitting device according to claim 1 , wherein the first resolution is higher than the second resolution.

5. a receiving unit that receives, as packets of objects constituting the content, a first packet of a first object having a first resolution via a first transmission path and receives, as packets of objects constituting the content, a second packet of a second object having a second resolution via a second transmission path; a control unit that, when the first transmission path is selected and the first packet is lost, complements the lost first packet with the second packet corresponding to the lost first packet.

6. information about a playback time for the first object based on the first packet is assigned to the first packet, and information about a playback time for the second object based on the second packet is assigned to the second packet; 6. The receiving device according to claim 5, wherein the control unit identifies the second packet corresponding to the missing first packet based on information about the playback times assigned to the first packet and the second packet.

7. the frequency band of the first transmission path is higher than the frequency band of the second transmission path; The receiving device according to claim 5 , wherein the first resolution is higher than the second resolution.

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