TRANSMISSION SYSTEM, ...RECEPTION SYSTEM, AND TRANSMISSION METHOD

Abstract

According to an embodiment, a transmission system comprises a sending system, a receiving system, an information collecting unit, and a synchronization control unit. The sending system can send video data and audio data to a connected network. The receiving system can receive video data and audio data via the network. The information collecting unit, which is provided in the sending system or the receiving system, collects synchronization control data in which a result of determination of a need for synchronization of video and audio is associated with a determination item. The synchronization control unit, which is provided in the sending system or the receiving system, selects, on the basis of the synchronization control data, either synchronized audio data from which audio can be output in synchronization with video, or non-synchronized audio data from which audio can be output independently of video.

Description

[Technical field]

[0001] The present invention relates to a transmission system, a sending system, a receiving system, and a transmission method. [Background technology]

[0002] In a multimedia content transmission system, a transmission system transmits video and audio input from a camera and microphone to a receiving system that can communicate with the transmission system via a network in a synchronized manner. Based on the transmitted video and audio, the receiving system displays the video on a video display device and plays the audio from a speaker. For example, when video and audio are shared in real time between distant systems, as long as the transmission delay of the video and audio does not exceed 50 milliseconds, problems are unlikely to occur when the systems work together. In addition, since the video and audio are synchronized with each other, the degree of delay in the audio is about the same as the degree of delay in the video. Therefore, a transmission system that can suppress delays related to the video and audio is required. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent No. 5595348 [Non-patent literature]

[0004] [Non-Patent Document 1] Yu Nishibori and 2 others, “Experiments and Considerations on Perception of Delay in a Performance System with Delay”, Information Processing Society of Japan Research Report, December 21, 2003, Vol. 127 (2003-MUS-053), pp. 37-42 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a transmission system, a sending system, a receiving system, and a transmission method that are capable of suppressing delays associated with video and audio. [Means for solving the problem]

[0006] According to an embodiment, a transmission system includes a transmission system, a receiving system, an information collecting unit, and a synchronization control unit. The transmission system can transmit video data and audio data to a connected network. The receiving system can receive the video data and audio data via the network. The information collecting unit is provided in the transmission system or the receiving system, and collects a determination result of whether or not synchronization of video and audio is required, in association with a determination item, as synchronization control data. The synchronization control unit is provided in the transmission system or the receiving system, and selects, based on the synchronization control data, either synchronous audio data capable of outputting audio in synchronization with video, or asynchronous audio data capable of outputting audio independent of video. Effect of the Invention

[0007] According to the embodiments, it is possible to provide a transmission system, a sending system, a receiving system, and a transmission method capable of suppressing delays associated with video and audio. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram illustrating a transmission system according to an embodiment. [Diagram 2] FIG. 2 is a block diagram illustrating a schematic hardware configuration of a transmission system and a reception system of the transmission system according to the embodiment. [Diagram 3] FIG. 3 is a flowchart illustrating an example of a process executed by the synchronization control unit of the transmission system according to the embodiment. [Figure 4] FIG. 4 is a block diagram illustrating a schematic modification of a transmission system according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] An embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

[0010] The transmission system 1 according to the embodiment is used, for example, when watching sports, entertainment, etc., at a remote location. In order for people watching and spectating at different locations (bases) to enjoy sports, entertainment, etc. at the same time, it is required to transmit the video and audio of sports, entertainment, etc. to the location where the people watching and spectating are watching and spectating with as little delay as possible. However, since the video and audio are usually transmitted in a synchronized state, the transmission of the audio is also delayed due to a delay in the transmission of the video. As a result, it may be difficult for people watching and spectating at remote locations to enjoy sports, entertainment, etc. at the same time (in cooperation with each other). The transmission system 1 according to the embodiment selects either synchronous audio data capable of outputting audio in synchronization with the video, or asynchronous (independent) audio data capable of outputting audio independent of the video, based on the synchronization control data. This allows people watching and spectating sports, entertainment, etc. to view synchronized video and audio at the timing when the video and audio synchronization is required. For example, when video of players during a game is being played, the video and audio are transmitted in synchronization, so that the people watching and spectating can view it without any discomfort. On the other hand, in cases where it is not necessary to synchronize the video and audio, such as when video from the spectator seats is being broadcast, the audio delay can be suppressed to below a certain threshold by transmitting the video and audio without synchronization. This allows spectators and spectators in different locations to work together to cheer on the team.

[0011] FIG. 1 is a block diagram showing a schematic diagram of a transmission system according to an embodiment. The transmission system 1 includes a transmission system 2 and a reception system 3. The transmission system 2 includes a photographing unit 21, a sound collecting unit 22, a video processing unit 23, an audio system 24, an encoder 25, a determination unit 26, and an information collecting unit 27. The determination unit 26 includes a video determination unit 261, a sound determination unit 262, a setting determination unit 263, and a volume determination unit 264. The reception system 3 includes a decoder 31, a synchronization control unit 32, an audio system 33, a video display unit 34, and a sound generating unit 35. The transmission system 2 and the reception system 3 can communicate with each other via a network 4. The network 4 is, for example, the Internet (registered trademark). The dashed lines in FIG. 1 indicate paths through which synchronization control data, which will be described later, is transmitted.

[0012] 2 is a block diagram showing a schematic hardware configuration of a transmission system and a reception system of a transmission system according to an embodiment. Each of the transmission system 2 and the reception system 3 is, for example, a computer. Each of the transmission system 2 and the reception system 3 includes a processor 41, a storage medium 42, a user interface 43, and a communication unit 44. The processor 41, the storage medium 42, the user interface 43, and the communication unit 44 are connected to each other via a bus 45.

[0013] The processor 41 includes any one of a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a microcomputer, a field programmable gate array (FPGA), and a digital signal processor (DSP), etc. The storage medium 42 may include an auxiliary storage device 47 in addition to a main storage device 46 such as a memory.

[0014] The main storage device 46 is a non-transient storage medium. The main storage device 46 is, for example, a non-volatile memory such as a hard disk drive (HDD) or a solid state drive (SSD) that can be written to and read from at any time, or a non-volatile memory such as a read only memory (ROM). These non-volatile memories may also be used in combination. The auxiliary storage device 47 is a tangible storage medium. The auxiliary storage device 47 is used in combination with the above-mentioned non-volatile memory and a volatile memory such as a random access memory (RAM). In the transmission system 2 and the reception system 3, only one processor 41 and one storage medium 42 may be provided, or multiple processors 41 and storage media 42 may be provided.

[0015] In each of the transmission system 2 and the reception system 3, the processor 41 performs processing by executing a program stored in a storage medium 42 or the like. In the transmission system 2 and the reception system 3, the program executed by the processor 41 may be stored in a computer (server) connected via a network such as the Internet, or in a server in a cloud environment. In this case, the processor 41 downloads the program via the network. In the transmission system 2, the video processing unit 23, the audio system 24, the encoder 25, the determination unit 26, and the information collection unit 27 perform at least a part of the processing performed by the processor 41 provided in the transmission system 2. In the reception system 3, the decoder 31, the synchronization control unit 32, and the audio system 33 perform at least a part of the processing performed by the processor 41 provided in the reception system 3.

[0016] In the user interface 43, various operations are input by a user of the transmission system 1, and information to be notified to the user is displayed, etc. The user interface may be a display unit 48 such as a display, or an input unit 49 such as a touch panel or a keyboard. Note that a device connected to the transmission system 2 and the reception system 3 may be used as the input unit 49, or an input unit of another information processing device capable of communicating via the network 4 may be used.

[0017] In one example, the transmission system 2 and the reception system 3 are servers capable of communicating with each other via a network 4. In another example, the transmission system 2 and the reception system 3 are cloud servers built in a cloud environment. In this case, the infrastructure of the cloud environment is composed of a virtual processor such as a virtual CPU and a cloud memory. A video processing unit 23, an audio system 24, an encoder 25, a determination unit 26, and an information collection unit 27 execute some of the processing executed by the virtual processor. In addition, a decoder 31, a synchronization control unit 32, and an audio system 33 execute some of the processing executed by the virtual processor.

[0018] The configuration of the transmission system 2 will be described. The photographing unit 21 photographs video (moving image) data. The photographing unit 21 is, for example, a camera. The sound collecting unit 22 collects audio data used in the video data photographed by the photographing unit 21. The sound collecting unit 22 is, for example, a microphone. The video processing unit 23 executes a predetermined process based on the video data photographed by the photographing unit 21. The video processing unit 23 executes, for example, a process of displaying text information, graphic information, etc., superimposed on the photographed video data. The audio system 24 executes a predetermined process based on the audio data collected by the sound collecting unit 22. The audio system 24 executes, for example, a process of adjusting the volume, etc., of the collected audio data to the most appropriate state for transmission via the network 4. The encoder 25 executes encoding based on the video data input from the video processing unit 23 and the audio data input from the audio system 24. The encoder 25 transmits the encoded video data and audio data to the receiving system 3 via the network 4.

[0019] The encoder 25 transmits both synchronous audio data capable of outputting audio in synchronization with the video data and asynchronous audio data capable of outputting audio independent of the video data to the receiving system 3 via the network 4. Both the synchronous audio data and the asynchronous audio data are audio data collected by the sound collection unit 22. Here, audio data transmitted to the receiving system 3 in synchronization with (together with) the video data is called synchronous audio data. Also, audio data transmitted to the receiving system 3 independently of (independent of) the video data is called asynchronous audio data. In this embodiment, the encoder 25 transmits the video data and the synchronous audio data together to the receiving system 3, and transmits the asynchronous audio data to the receiving system 3 independently of the video data. Therefore, the asynchronous audio data is transmitted to the receiving system 3 without being affected by the processing of the video data or the transmission speed of the video data on the network 4. The determination unit 26 determines whether or not synchronization is required based on the video data captured by the imaging unit 21 and the audio data collected by the sound collection unit 22. The information collection unit 27 collects the judgment results generated by the judgment unit 26, and transmits the judgment results and the judgment items used in the judgment in association with each other to the receiving system 3 via the network 4.

[0020] The configuration of the receiving system 3 will be described. The decoder 31 decodes video and audio. The decoded video data is output to the video display unit 34, and the decoded audio data is output to the synchronization control unit 32. At this time, the synchronization control unit 32 acquires both the synchronous audio data and the asynchronous audio data from the decoder 31. The synchronization control unit 32 acquires, from the transmission system 2, synchronization control data in which the judgment result and the judgment item are associated with each other. The synchronization control unit 32 executes a process described later based on the synchronization control data, and selects either the synchronous audio data or the asynchronous audio data. The synchronization control unit 32 outputs the selected audio data to the audio system 33. The audio system 33 executes a predetermined process based on the input audio data. The audio system 33 executes a process to adjust the volume so that the volume is appropriate for playback from the sound output unit 35, for example. The video display unit 34 displays the input video data. The video display unit 34 is, for example, a display or a projector. The sound output unit 35 reproduces the input audio data. The sound output unit 35 is, for example, a speaker.

[0021] Next, a description will be given of the determination unit 26 and the information collection unit 27 of the transmission system 2. The determination unit 26 includes the video determination unit 261, the audio determination unit 262, the setting determination unit 263, and the volume determination unit 264, as described above.

[0022] The video determination unit 261 acquires video data to be used for the determination from the imaging unit 21. The video determination unit 261 determines the type of video based on the acquired video data. In one example, the video determination unit 261 determines whether the video is a long shot or a close-up based on the acquired video data. The video determination unit 261 may determine the above-mentioned video data based on, for example, a result of prior learning by machine learning. The video determination unit 261 outputs the determination result of the video data to the information collection unit.

[0023] The voice determination unit 262 acquires voice data to be used for the determination from the sound collection unit 22. The voice determination unit 262 determines the type of voice based on the acquired voice data. In one example, the voice determination unit 262 determines whether the voice is a cheer based on the acquired voice data. The voice determination unit 262 may determine the above-mentioned voice data based on, for example, a result of prior learning by machine learning. The voice determination unit 262 outputs the determination result of the voice data to the information collection unit 27.

[0024] The setting determination unit 263 acquires, for example, setting information of the photographing unit 21 as equipment data from the photographing unit 21. The setting information includes information on the focal length of the lens. The setting determination unit 263 judges whether the photographing unit 21 is photographing a close-up image or a long-distance image based on the acquired setting information and a preset threshold. That is, if the focal length of the lens is greater than the preset threshold, it is determined that the photographing unit 21 is photographing a close-up image, and if the focal length of the lens is equal to or less than the preset threshold, it is determined that the photographing unit 21 is photographing a long-distance image. The setting determination unit 263 outputs the judgment result of the photographing unit 21 to the information collecting unit 27, and also outputs the setting information of the photographing unit 21 to the information collecting unit 27. For example, the preset threshold for the focal length of the lens is 100 mm when the photographing unit 21 is a camera with a 35 mm image sensor.

[0025] The volume determination unit 264 acquires audio data to be used for the determination from the sound collection unit 22. The volume determination unit 264 determines the type of audio based on the volume of the acquired audio data. In one example, the volume determination unit 264 determines whether the audio data is cheering or not based on the volume of the acquired audio data and a preset volume threshold. The volume of the audio data includes, for example, information indicating the gain value (volume) of the cheering input from a microphone installed in the audience seats. The volume determination unit 264 outputs the determination result of the volume of the audio data to the information collection unit 27. The preset volume threshold is, for example, 75.0 dB.

[0026] The information collecting unit 27 acquires the judgment result of the video data, the judgment result of the audio data, and the judgment result based on the equipment data from the judgment unit 26 described above. The information collecting unit 27 associates information indicating that the judgment result by the video judgment unit 261 is related to the video data with the judgment result by the video judgment unit 261. The information collecting unit 27 associates information indicating that the judgment result by the audio judgment unit 262 is related to the audio data with the judgment result by the audio judgment unit 262. The information collecting unit 27 associates information indicating that the judgment result by the setting judgment unit 263 is related to the equipment data with the judgment result by the setting judgment unit 263. The information collecting unit 27 associates information indicating that the judgment result by the volume judgment unit 264 is related to the audio data with the judgment result by the volume judgment unit 264. The information collecting unit 27 transmits the synchronization control data in which the judgment result and the judgment item are associated with each other to the synchronization control unit 32 via the network 4 as described above.

[0027] Next, the synchronization control unit 32 will be described. The synchronization control unit 32 selects audio data to be output from the sound output unit 35 of the receiving system 3 based on the synchronization control data. The synchronization control unit 32 selects appropriate audio data by executing processing corresponding to the judgment item and judgment result included in the synchronization control data. When the judgment item is related to video data and the judgment result indicates that the type of video is a close-up, the synchronization control unit 32 selects synchronized audio data as the audio data to be output. When the judgment item is related to audio data and the judgment result indicates that the type of audio is other than cheering, the synchronization control unit 32 selects synchronized audio data as the audio data to be output. When the judgment item is related to equipment data and the judgment result indicates that the focal length exceeds a threshold, the synchronization control unit 32 selects synchronized audio data as the audio data to be output. When the judgment item is related to audio data and the judgment result indicates that the volume of the audio data exceeds a threshold, the synchronization control unit 32 selects synchronized audio data as the audio data to be output. In these cases, low delay is not required when transmitting audio data relative to the transmission of video data, so the synchronization control unit 32 selects synchronized audio data as the audio data to be output. In other cases, the synchronization control unit 32 selects asynchronous audio data as the audio data. That is, in this case, since low delay is required when transmitting audio data relative to the transmission of video data, the synchronization control unit 32 selects asynchronous audio data as the audio data to be output. The synchronization control unit 32 outputs the audio data selected as described above to the audio system 33. In the above-mentioned processing, the synchronization control unit 32 may use any one of the judgment items and judgment results included in the synchronization control data, or may use a combination of multiple judgment items and judgment results.

[0028] The synchronization control unit 32 acquires in advance from the receiving system 3 reference information that is a criterion for judging the audio data. The reference information includes data such as a threshold value used to judge the synchronization between the video data and the audio data, and a judgment period (time interval) for executing the judgment of synchronization. The threshold value used to judge the synchronization is, for example, that when a plurality of judgment results are used to judge whether or not it is necessary to select the synchronized audio data, the ratio of judgment results that select the synchronized audio data is 50% or more. In this case, when the ratio of judgment results that select the synchronized audio data is 50% or more, the synchronized audio data is selected, and when the ratio of judgment results that select the synchronized audio data is less than 50%, the asynchronous audio data is selected. In addition, the judgment period is, for example, 1 / 60 seconds when the image capturing unit 21 is a camera that captures 60 images per second.

[0029] When the synchronization control unit 32 selects audio data, the audio data may switch from synchronous audio data to asynchronous audio data or from asynchronous audio data to synchronous audio data before and after the selection. At this time, the synchronization control unit 32 may execute a predetermined buffering process to suppress unnatural sound changes (e.g., the occurrence of silent periods and breaks in audio waveforms) that accompany the switching of audio data. The buffering process is, for example, a process in which, rather than switching the audio data instantly, audio data is gradually reduced in volume before the switching and audio data gradually increased in volume after the switching are synthesized and output.

[0030] Fig. 3 is a flowchart for explaining an example of processing executed by the synchronization control unit 32. The processing in Fig. 3 is executed by the synchronization control unit 32 every time video data and audio data are input from the transmission system 2 to the reception system 3. Therefore, the processing in Fig. 3 shows an example of processing executed upon input of audio data to the transmission system 1.

[0031] When the process of FIG. 3 is started, the synchronization control unit 32 acquires reference information that is a judgment criterion for audio data from the receiving system 3 (S101). The synchronization control unit 32 acquires synchronization control data in which the judgment result and the judgment item are associated from the transmitting system 2 via the network 4 (S102). If the time (delay time) required to transmit the video data and audio data from the transmitting system 2 to the receiving system 3 is equal to or greater than the time threshold (S103-Yes), the synchronization control unit 32 judges whether or not acquisition of the synchronized audio data is completed (S104). If acquisition of the synchronized audio data is completed (S104-Yes), the synchronization control unit 32 selects the synchronized audio data as the audio data to be output (S106). If acquisition of the synchronized audio data is not completed (S104-No), the synchronization control unit 32 selects the asynchronous audio data as the audio data to be output (S107). In this way, if the delay time is equal to or greater than the time threshold, the audio reproduction can be prevented from being stopped by selecting the audio data that has been acquired as the audio data to be output.

[0032] If the time (delay time) required to transmit the video data and audio data from the transmitting system 2 to the receiving system 3 is less than the time threshold (S103-No), the synchronization control unit 32 judges whether or not priority is given to low-delay audio data (S105). Whether or not low-delay is prioritized is judged according to the judgment result and judgment item included in the synchronization control data, as described above. If low-delay is prioritized (S105-Yes), the process proceeds to S104, and the processes from S104 onwards are executed. If low-delay is not prioritized (S105-No), the synchronization control unit 32 selects asynchronous audio data as the audio data to be output (S107).

[0033] The synchronization control unit 32 determines whether or not the selection of the audio data to be output has resulted in a change between the audio data before the selection and the audio data after the selection (S108). If the audio data has been changed (S108-Yes), the synchronization control unit 32 executes the buffering process described above (S109). Thereafter, the synchronization control unit 32 outputs the audio data for which the buffering process has been executed (S110). If the audio data has not been changed (S108-No), the synchronization control unit 32 does not execute S109, and the process proceeds to S110. By outputting the audio data, the audio data is input to the audio system 33, and audio is output from the sound output unit 35. The audio output from the sound output unit 35 is appropriately executed in accordance with the reproduction of the video data on the video display unit 34.

[0034] The synchronization control unit 32 judges whether or not the determination period of the voice data acquired as the reference information has been exceeded (S111). If the determination period is not exceeded (S111-No), the process returns to S111, and the synchronization control unit 32 executes the process from S111 onwards. If the determination period has been exceeded (S111-Yes), the synchronization control unit 32 judges whether or not the input of voice data is continuing (S112). If the input of voice data is continuing (S112-Yes), the process returns to S102, and the synchronization control unit 32 executes the process from S102 onwards. If the input of voice data is not continuing (S112-No), the process ends.

[0035] As described above, the transmission system 1 of the present embodiment includes an information collecting unit 27 and a synchronization control unit 32. The information collecting unit 27 associates the judgment result of whether or not synchronization between video and audio is required with the judgment item, and collects them as synchronization control data. The synchronization control unit 32 selects either synchronous audio data capable of outputting audio in synchronization with video, or asynchronous audio data capable of outputting audio independent of video, based on the synchronization control data. This allows the transmission system 1 to output asynchronous audio data at an appropriate timing. Therefore, in the transmission system of the present embodiment, audio is transmitted without waiting for the transmission of video, so that audio delay can be suppressed to, for example, 50 milliseconds or less. This allows people watching or spectating at separate locations to cooperate with each other and cheer on the team.

[0036] In the transmission system 1 of this embodiment, it is preferable that the synchronization control unit 32 selects synchronous audio data when the synchronization control data is information that requires low audio delay, and selects asynchronous audio data when the synchronization control data is information that does not require low audio delay. This allows the transmission system 1 to output asynchronous audio data that is not synchronized with video at an appropriate timing.

[0037] In the transmission system 1 of this embodiment, when the output audio is switched between synchronous audio data and asynchronous audio data by selection based on the synchronization control data, the synchronization control unit 32 preferably performs an audio buffering process. This makes it possible to suppress unnatural sounds that occur with audio data switching, and allows the viewer to continue watching the video and audio without feeling uncomfortable.

[0038] By using such a transmission system 1, for example, when the video is a close-up (such as when a sports player is shot in a zoomed-in shot), the video and audio are played back in sync, and when the video switches to a long shot (such as when the entire spectator stands are shot), the video and audio are played back asynchronously. Therefore, the viewer of the video can continue watching without feeling uncomfortable, because the video and audio are synchronized at the timing when the viewer of the video notices the discrepancy between the video and audio. Furthermore, because the video and audio are played back asynchronously at a timing other than the timing when the viewer of the video notices the discrepancy between the video and audio, delays related to the video and audio can be suppressed without the viewer feeling uncomfortable.

[0039] (Modification) FIG. 4 is a schematic block diagram showing a modified example of the transmission system of the embodiment. In this modified example, a plurality of encoders 25 are provided in the transmission system 2, and a plurality of decoders 31 are provided in the reception system 3. In the example of FIG. 4, the transmission system 2 includes two encoders 251 and 252, and the reception system 3 includes two decoders 311 and 312. In this case, the encoder 251 synchronizes the video data output from the video processing unit 23 and the audio data output from the audio system 24, and transmits them from the transmission system 2 to the reception system 3 via the network 4 (indicated by a solid arrow). In addition, the encoder 252 transmits the asynchronous audio data output from the audio system 24 from the transmission system 2 to the reception system 3 via the network 4 independently of the video data without synchronizing it with the video data (indicated by a dashed arrow). Meanwhile, the decoder 311 decodes the received video data and synchronous audio data, outputs the video data to the video display unit 34, and outputs the synchronous audio data to the synchronization control unit 32 (indicated by a solid arrow). Moreover, the decoder 312 outputs the received asynchronous audio data to the synchronization control unit 32 (indicated by the dashed arrow). In this modification, the transmission system 1 can also select either the synchronous audio data or the asynchronous audio data based on the synchronization control data. Therefore, these modifications also provide the same effects as the above-described embodiment.

[0040] In one modified example, the information collecting unit 27 and the synchronization control unit 32 may be provided in the transmitting system 2. In another modified example, the information collecting unit 27 and the synchronization control unit 32 may be provided in the receiving system 3. In these modified examples, the synchronization control unit 32 acquires the synchronization control data from the information collecting unit 27 without going through the network 4. In these modified examples, the transmission system 1 can also select either synchronous audio data or asynchronous audio data based on the synchronization control data. Therefore, these modified examples also have the same effects as the above-mentioned embodiment.

[0041] The method described in the embodiments and the like may be distributed by storing it in a storage medium such as a magnetic disk, an optical disk, or a semiconductor memory as a program (software) that can be executed by a computer. The storage medium is not limited to a storage medium for distribution, but includes a storage medium such as a magnetic disk or a semiconductor memory provided inside a computer or in a device connected via a network. The method described in the embodiments may be distributed by transmitting it through a communication medium. The program stored on the medium side includes a setting program that configures the software to be executed by a computer within the computer. The software includes not only an execution program but also a table and a data structure. The computer that realizes this system reads the program recorded in the storage medium and executes the above-mentioned process by being controlled by the software. The software may be constructed by the computer using a setting program.

[0042] The present invention is not limited to the above-mentioned embodiment, and can be modified in various ways without departing from the gist of the present invention. The embodiments may be combined as appropriate, and in that case, the combined effect can be obtained. Furthermore, the above-mentioned embodiment includes various inventions, and various inventions can be extracted by combinations selected from the multiple components disclosed. For example, if the problem can be solved and the effect can be obtained even if some components are deleted from all the components shown in the embodiment, the configuration from which the components are deleted can be extracted as an invention. [Explanation of symbols]

[0043] 1. Transmission system 2. Transmission system 3. Receiving system 4. Network 21…Photography Department 22…Sound collection section 23...Image processing section 24…Audio system 25,251,252…Encoder 26…Judgment section 27…Information Gathering Department 31,311,312…decoder 32...Synchronization control section 33…Audio system 34...Video display section 35…Phonetic section

Claims

1. a transmission system capable of transmitting video data and audio data to a connected network; a receiving system capable of receiving the video data and the audio data via the network; an information collection unit that is provided in the transmission system or the reception system and that collects a determination result of whether or not synchronization of video and audio is required as synchronization control data by associating the result with a determination item of the determination result; a synchronization control unit provided in the transmitting system or the receiving system, which selects, based on the synchronization control data, either synchronous audio data capable of outputting audio in synchronization with video or asynchronous audio data capable of outputting audio independent of video; Equipped with The transmission system includes the information collecting unit, the receiving system is a system separate from the transmitting system, and includes the synchronization control unit; The synchronization control unit acquires the synchronization control data from the information collection unit.

2. the synchronization control unit selects the synchronous audio data when the synchronization control data is information requesting low audio delay, and selects the asynchronous audio data when the synchronization control data is information not requesting low audio delay. The transmission system according to claim 1 .

3. the synchronization control unit executes a buffering process for the audio when the audio to be output is switched between the synchronous audio data and the asynchronous audio data by selection based on the synchronization control data.

3. A transmission system according to claim 1 or 2.

4. The synchronization control data includes at least one selected from the synchronization control data related to the video data, the synchronization control data related to the audio data, and the synchronization control data related to equipment data. A transmission system according to any one of claims 1 to 3.

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