Video transmission system and source device

Abstract

To improve the convenience of a user.SOLUTION: A video transmission system according to an embodiment includes a source device and a plurality of sink devices. The source device supplies content including a video signal and an audio signal. The source device includes a plurality of ports, a priority setting unit, a first output control unit, and a second output control unit. The plurality of ports are for connecting a plurality of sink devices. The first priority setting section sets a video priority and an audio priority to a port whose connection destination is active. The first control unit determines to use a port having the highest video priority for outputting video signal. The second output control unit determines to use the port having the highest audio priority for outputting an audio signal.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE INVENTION An embodiment of the present invention relates to a video transmission system and a source device. [Background technology]

[0002] Many source devices that supply video content, such as Blu-ray (registered trademark) players, support the HDMI (registered trademark) standard (High Definition Multimedia Interface).

[0003] Some source devices that support the HDMI standard are equipped with a sub-HDMI port for audio output in addition to the main HDMI port, allowing them to output video and audio signals separately. Such source devices output both video and audio signals from the main port when a sink device (such as a television) is connected only to the main port, but when sink devices are connected to both the main and sub-ports (for example, when a television is connected to the main port and an AV (Audio Visual) amplifier is connected to the sub-port), the device automatically switches between output modes, outputting the video signal from the main port and the audio signal from the sub-port. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-258867 Summary of the Invention [Problem to be solved by the invention]

[0005] The HDMI ports on the above-mentioned source devices have fixed roles, and if you connect them incorrectly, such as connecting a TV to the sub-port, you will end up with no video or audio. There is also no concept of a port dedicated to video output. Furthermore, there is only one main port and one port for audio output.

[0006] As described above, conventional source devices are inconvenient for users, as problems can occur due to incorrect cable connections by the user.

[0007] The problem to be solved by the present invention is to provide a video transmission system and a source device that can improve user convenience. [Means for solving the problem]

[0008] According to one embodiment, the video transmission system includes a source device and a plurality of sink devices. The source device supplies content data including a video signal and an audio signal. The plurality of sink devices are connected to the source device and are capable of receiving the content data from the source device. The source device includes a plurality of ports, a first priority setting unit, a first output control unit, a second priority setting unit, and a second output control unit. The plurality of ports are for connecting the plurality of sink devices. The first priority setting unit sets a video priority, which is a priority for the video signal, for a port of the plurality of ports that is an active connection destination. The first output control unit determines to use the port with the highest video priority for outputting the video signal. The second priority setting unit sets an audio priority, which is a priority for the audio signal, for a port of the plurality of ports that is an active connection destination. The second output control unit determines to use the port with the highest audio priority for outputting the audio signal. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram showing a video transmission system according to an embodiment. [Figure 2] FIG. 2 is a block diagram showing the hardware configuration of a source device according to the embodiment. [Figure 3] 4 is a flowchart showing a procedure for output switching control according to the embodiment. [Figure 4] 5A and 5B are diagrams for explaining a specific example of output switching control according to the embodiment. [Figure 5] 5A and 5B are diagrams for explaining a specific example of output switching control according to the embodiment. [Figure 6] 5A and 5B are diagrams for explaining a specific example of output switching control according to the embodiment. [Figure 7] 5A and 5B are diagrams for explaining a specific example of output switching control according to the embodiment. [Figure 8] FIG. 1 is a diagram for explaining a video transmission system according to a related art. [Figure 9] FIG. 1 is a diagram for explaining a video transmission system according to a related art. [Figure 10] FIG. 1 is a diagram for explaining a video transmission system according to a related art. [Figure 11] FIG. 1 is a diagram for explaining a video transmission system according to a related art. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment will be described with reference to the drawings.

[0011] First, a video transmission system according to the related art will be described.

[0012] Fig. 8 schematically shows a video transmission system 800 according to the related art. As shown in Fig. 8, the video transmission system 800 includes a Blu-ray player 810, a television 820, an AV amplifier 830, and HDMI cables 840 and 850. The Blu-ray player 810, the television 820, and the AV amplifier 830 support the HDMI standard, and the television 820 is connected to the Blu-ray player 810 via the HDMI cable 840, and the AV amplifier 830 is connected via the HDMI cable 850.

[0013] Blu-ray player 810 has two HDMI ports 811 and 812. HDMI port 811 is a main port configured to output both video and audio signals, while HDMI port 812 is a sub-port dedicated to audio output configured to output only audio signals. HDMI port 811 is connected to television 820 via HDMI cable 840. HDMI port 812 is connected to AV amplifier 830 via HDMI cable 850.

[0014] The advantage of providing two HDMI ports—a main port and a sub-port dedicated to audio output—is that they enable higher image and sound quality. For example, transmitting video and audio signals over separate cables reduces transmission errors, jitter, and other transmission disturbances, enabling more accurate signal transmission. As shown in FIG. 10, a Blu-ray player may be connected to a television and surround speakers via an AV amplifier. In this connection configuration, assume that the Blu-ray player and television support 4K resolution, while the AV amplifier supports 2K resolution but not 4K. In this case, a 2K video signal is supplied to the television, resulting in degraded image quality. When a Blu-ray player 810 is provided with a main port and a sub-port dedicated to audio output, the video signal can be bypassed, as shown in FIG. 11. As a result, a 4K video signal can be supplied to a television even when using an AV amplifier that does not support 4K resolution.

[0015] Referring again to Figure 8, the Blu-ray player 810 reads video content data including a video signal (video data) and an audio signal (audio data) from a Blu-ray disc, outputs the video signal from HDMI port 811, and selectively outputs the audio signal from one of HDMI ports 811 and 812. For example, as shown in Figure 8, when the power of both the television 820 and the AV amplifier 830 is ON, the Blu-ray player 810 outputs the video signal from HDMI port 811 and outputs the audio signal from HDMI port 812. Furthermore, as shown in Figure 9, when the power of the television 820 is ON and the power of the AV amplifier 830 is OFF, the Blu-ray player 810 outputs both the video signal and the audio signal from HDMI port 811, but does not output the audio signal from HDMI port 812.

[0016] As described above, in Blu-ray player 810 according to the related art, the roles of HDMI ports 811 and 812 are fixed. Specifically, HDMI port 811 is a main port, and HDMI port 812 is a sub-port for audio output. It is very difficult for a general user to know to which HDMI port 811 or 812 television 820 and AV amplifier 830 should be connected. For example, if a user mistakenly connects television 820 to HDMI port 812, video (images based on video signals) will not be displayed on television 820. Alternatively, if a device that cannot handle audio signals, such as a projector, is connected to HDMI port 812, video will not be displayed and audio will not be output (sound will not be produced).

[0017] Next, a video transmission system according to an embodiment will be described.

[0018] Fig. 1 schematically illustrates an exemplary configuration of a video transmission system 100 according to an embodiment. As illustrated in Fig. 1, the video transmission system 100 includes a source device (also referred to as a source apparatus) 10, sink devices (also referred to as sink devices) 20, 22, and 24, and HDMI cables 21, 23, and 25. The source device 10 is connected to the sink device 20 via the HDMI cable 21, to the sink device 22 via the HDMI cable 23, and to the sink device 24 via the HDMI cable 25.

[0019] The source device 10 supplies video content data including a video signal and an audio signal. Examples of the source device 10 include, but are not limited to, a digital video recorder, an optical disc player, a set-top box, a personal computer, etc.

[0020] 1, the source device 10 is a Blu-ray player. The source device 10 reads video content data from a Blu-ray disc and selectively supplies the read video content data to sink devices 20, 22, and 24. The source device 10 is not limited to reading video content data from Blu-ray discs, but can also read video content data from other computer-readable recording media such as DVDs (digital versatile discs).

[0021] Each of sink devices 20, 22, and 24 receives video content data from source device 10 and outputs the received video content data to a user. Sink devices 20, 22, and 24 may be devices capable of processing both video signals and audio signals, or devices capable of processing only video signals or audio signals. Examples of sink devices include, but are not limited to, image display devices such as televisions, monitors, and projectors, and audio devices such as 5.1-channel surround amplifiers and sound bars.

[0022] 1, sink device 20 is a 4K television and is capable of processing both video and audio signals. Specifically, sink device 20 includes a display device and a speaker. Sink device 20 supports 4K resolution as a video format and L-PCM (Linear PCM), MPEG1, MP3, and MPEG2 as audio formats.

[0023] 1, the sink device 22 is a 5.1ch surround amplifier and is capable of processing both video signals and audio signals. For example, a display device (not shown) and 5.1ch surround speakers (not shown) are connected to the sink device 22, and the sink device 22 can output video signals to the display device and audio signals to the 5.1ch surround speakers. The sink device 22 supports 2K as a video format and L-PCM, MPEG1, MP3, MPEG2, AC-3, and MPEG-H3D as audio formats.

[0024] 1, the sink device 24 is an 8K projector and is capable of processing both video and audio signals. Specifically, the sink device 24 can project video and output audio signals to an audio device (not shown). The sink device 24 supports 8K resolution as a video format and L-PCM as an audio format.

[0025] In this embodiment, the source device 10 and sink devices 20, 22, and 24 support the HDMI standard and are configured to transmit and receive digital signals compliant with the HDMI standard to and from external devices connected via HDMI cables. The source device 10 receives Extended Display Information Data (EDID), which indicates the configuration and status of each sink device, from each sink device 20, 22, and 24 using the Display Data Channel (DDC) channel of the HDMI cable. The EDID includes data indicating the functions and capabilities supported by the sink device based on a format defined in the CTA-861 standard. For example, the source device 10 receives from the sink device 20 an EDID including information indicating the video and audio formats supported (capable of being handled) by the sink device 20, receives from the sink device 22 an EDID including information indicating the video and audio formats supported by the sink device 22, and receives from the sink device 24 an EDID including information indicating the video and audio formats supported by the sink device 24. By receiving EDID from the sink devices 20, 22, and 24, the source device 10 recognizes the video and audio formats supported by each of the sink devices 20, 22, and 24.

[0026] The source device 10 will now be described in detail.

[0027] The source device 10 includes a disc drive 11, a video signal output unit 12, an audio signal output unit 13, a control unit 14, and HDMI ports 15, 16, and 17.

[0028] HDMI ports 15, 16, and 17 are AV output interfaces that comply with the HDMI standard and are intended for connecting HDMI cables. HDMI ports 15, 16, and 17 are configured to be able to output both video and audio signals. One end of an HDMI cable 21 is connected to HDMI port 15, and the other end of the HDMI cable 21 is connected to an HDMI port (not shown) of sink device 20. One end of an HDMI cable 23 is connected to HDMI port 16, and the other end of the HDMI cable 23 is connected to an HDMI port (not shown) of sink device 22. One end of an HDMI cable 25 is connected to HDMI port 17, and the other end of the HDMI cable 25 is connected to an HDMI port (not shown) of the sink device.

[0029] Although FIG. 1 shows a configuration in which the source device 10 has three HDMI ports 15 to 17, the number of HDMI ports may be two or four or more.

[0030] The disc drive 11 reads content data from an optical disc such as a Blu-ray disc, sends the video signal contained in the content data to the control unit 14 via the video signal output unit 12, and sends the audio signal contained in the content data to the control unit 14 via the audio signal output unit 13.

[0031] Control unit 14 receives a video signal from video signal output unit 12 and an audio signal from audio signal output unit 13. Control unit 14 selectively outputs the video signal from one of HDMI ports 15, 16, and 17. Specifically, control unit 14 selects an HDMI port from HDMI ports 15, 16, and 17 to use for outputting the video signal, and outputs the video signal from the selected HDMI port. Control unit 14 selectively outputs an audio signal from one of HDMI ports 15, 16, and 17. Specifically, control unit 14 selects an HDMI port from HDMI ports 15, 16, and 17 to use for outputting the audio signal, and outputs the audio signal from the selected HDMI port.

[0032] The control unit 14 includes priority setting units 141 and 142 and output control units 143 and 144 .

[0033] The priority setting unit 141 virtually sets priorities for video signals to the HDMI ports 15, 16, and 17. Hereinafter, the priorities for video signals will be referred to as video priorities.

[0034] In one example, the priority setting unit 141 sets a video priority for an HDMI port among HDMI ports 15, 16, and 17 to which a connected sink device is active, according to the resolution of the video format supported by the sink device. An active sink device means that the sink device is powered on. An inactive sink device means that the sink device is powered off. The resolution of the video format supported by a sink device corresponds to the maximum resolution that the sink device can output. In this description, it is assumed that sink devices 20, 22, and 24 are all active. The higher the resolution, the higher the video priority set by the priority setting unit 141. In this example, sink device 24 supports the video format with the highest resolution, sink device 20 supports the video format with the second highest resolution, and sink device 22 supports the video format with the lowest resolution. In this case, the priority setting unit 141 sets the highest video priority to the HDMI port 17 connected to the sink device 24, the second highest video priority to the HDMI port 15 connected to the sink device 20, and the lowest video priority to the HDMI port 16 connected to the sink device 22.

[0035] Output control unit 143 controls video output (output of video signals). Specifically, output control unit 143 determines which HDMI port among HDMI ports 15, 16, and 17 has the highest video priority to use for outputting the video signal, and outputs the video signal from the HDMI port determined to be used for outputting the video signal.

[0036] Each time any of the connected sink devices becomes active or inactive, the priority setting unit 141 executes a process of setting a video priority, and the output control unit 143 executes a process of switching the video output between the HDMI ports 15, 16, and 17 in response to the video priority setting.

[0037] The output control unit 143 notifies the video signal output unit 12 of the video format supported by the sink device connected to the HDMI port that outputs the video signal. The video signal output unit 12 converts the video signal received from the disc drive 11 in accordance with the video format notified by the output control unit 143. The output control unit 143 outputs the converted video signal from the HDMI port.

[0038] The priority setting unit 142 virtually sets priorities for audio signals to the HDMI ports 15, 16, and 17. Hereinafter, the priorities for audio signals will be referred to as audio priorities.

[0039] In one example, the priority setting unit 142 sets a video priority for an HDMI port among HDMI ports 15, 16, and 17 to which a connected sink device is active, according to the number of audio formats supported by the sink device. In this description, it is assumed that sink devices 20, 22, and 24 are active. The priority setting unit 142 sets a higher audio priority for a port with a greater number of audio formats. In this example, sink device 20 supports four audio formats, sink device 22 supports six audio formats, and sink device 24 supports one audio format. In this case, the priority setting unit 142 sets the highest audio priority to HDMI port 16 connected to sink device 22, the second highest audio priority to HDMI port 15 connected to sink device 20, and the lowest audio priority to HDMI port 17 connected to sink device 24.

[0040] The output control unit 144 controls the audio output (output of the audio signal). Specifically, the output control unit 144 determines which HDMI port among the HDMI ports 15, 16, and 17 has the highest audio priority to use for outputting the audio signal, and outputs the audio signal from the HDMI port determined to be used for outputting the audio signal.

[0041] Each time any of the connected sink devices becomes active or inactive, the priority setting unit 142 performs a process of setting an audio priority, and the output control unit 144 performs a process of switching the audio output between the HDMI ports 15, 16, and 17 in response to the audio priority setting.

[0042] In the above example, audio priorities are set according to the number of audio formats. In another example, audio priorities may be set according to the sound quality of the audio formats. For example, the priority setting unit 142 may store information in which audio formats are ranked in advance by sound quality, and set a high audio priority to an HDMI port connected to a sink device that supports an audio format with high sound quality.

[0043] The output control unit 144 notifies the audio signal output unit 13 of the audio format supported by the sink device connected to the HDMI port that outputs the audio signal. The audio signal output unit 13 converts the audio signal received from the disc drive 11 in accordance with the audio format notified by the output control unit 144. The output control unit 144 outputs the converted audio signal from the HDMI port.

[0044] If the HDMI port with the highest video priority and the HDMI port with the highest audio priority are the same port, both the video and audio signals will be output from that port. On the other hand, if the port with the highest video priority is different from the port with the highest audio priority, the video and audio signals will be output from separate HDMI ports.

[0045] In the source device 10 having the above configuration, output switching is performed so that a video signal is sent to the sink device that supports the highest resolution among the active sink devices, and an audio signal is sent to the sink device that supports the most audio formats among the active sink devices. This allows for more appropriate automatic switching, making it possible to connect any sink device to any HDMI port. It also becomes possible to support video-only devices. As a result, user convenience is improved.

[0046] 2 shows a schematic example of the hardware configuration of the source device 10. As shown in Fig. 2, the source device 10 includes, as hardware elements, a processor 101, a memory 102, a disk drive 103, and an input / output interface 104. The processor 101 exchanges signals with the memory 102, the disk drive 103, and the input / output interface 104.

[0047] The processor 101 includes, for example, a CPU (Central Processing Unit). The memory 102 includes RAM (Random Access Memory) and a program memory. The RAM is a volatile memory and is used as a working area for the processor 101. The program memory is a non-volatile memory and stores a control program. When executed by the processor 101, the control program causes the processor 101 to perform a series of processes described below with respect to the video signal output unit 12, the audio signal output unit 13, and the control unit 14. In other words, the processor 101 functions as the video signal output unit 12, the audio signal output unit 13, and the control unit 14.

[0048] The disc drive 103 corresponds to the disc drive 11 shown in Fig. 1. The disc drive 103 reads video content data from an optical disc such as a Blu-ray disc, and sends the read video content data to the processor 101.

[0049] The input / output interface 104 is an interface for connecting external devices, and includes the HDMI ports 15, 16, and 17 shown in Fig. 1. The input / output interface 104 may also include other physical ports, such as a LAN (Local Area Network) port for connecting a LAN cable.

[0050] The processor 101 may include a dedicated processor such as an FPGA (Field Programmable Gate Array) instead of or in addition to a general-purpose processor such as a CPU.

[0051] The operation of the source device 10 will be described.

[0052] Fig. 3 shows an example of a procedure for output switching control executed by the source device 10. The process shown in Fig. 3 starts when the source device 10 is powered on.

[0053] In step S301 of FIG. 3, the control unit 14 determines whether or not there is an HDMI port among the HDMI ports 15, 16, and 17 to which the sink device to be connected is active.

[0054] If the destination sink device does not have an active HDMI port (step S301; No), the flow proceeds to step S304.

[0055] If the destination sink device has an active HDMI port (step S301; Yes), the flow proceeds to step S302. In step S302, the control unit 14 sets a video priority and an audio priority for the HDMI port among the HDMI ports 15, 16, and 17 to which the active sink device is connected. For example, the priority setting units 141 and 142 receive EDID from the active sink device and recognize the video format and audio format supported by the active sink device based on the received EDID. The priority setting unit 141 sets a video priority for the HDMI port to which the active sink device is connected, depending on the resolution of the video format supported by the active sink device. Specifically, the priority setting unit 141 sets a higher video priority for the HDMI port to which the active sink device is connected, which supports a higher resolution. The priority setting unit 142 sets an audio priority for the HDMI port to which the active sink device is connected, depending on the number of audio formats supported by the active sink device. Specifically, the priority setting unit 142 sets a high audio priority to an HDMI port to which an active sink device that supports many audio formats is connected.

[0056] In step S303, the output control unit 143 of the control unit 14 determines the HDMI port with the highest video priority as the HDMI port to be used for outputting the video signal, and the output control unit 144 of the control unit 14 determines the HDMI port with the highest audio priority as the HDMI port to be used for outputting the audio signal.

[0057] In step S304, the control unit 14 waits until the power of any of the sink devices 20, 22, and 24 connected to the HDMI ports 15, 16, and 17 is switched on or off.

[0058] When the power supply of any of the sink devices 20, 22, and 24 is switched (step S304; Yes), the flow returns to step S302. The control unit 14 sets the video priority and audio priority again (step S302), and switches the video output and audio output (step S303).

[0059] The flow shown in FIG. 3 ends when the power of the source device 10 is turned off.

[0060] A specific example of the output switching control described with reference to Fig. 3 will be described. Here, it is assumed that a television serving as sink device 20 is connected to HDMI port 15 of source device 10, an amplifier serving as sink device 22 is connected to HDMI port 16 of source device 10, and a projector serving as sink device 24 is connected to HDMI port 17 of source device 10, as in the example shown in Fig. 1. In the following, sink device 20 will be referred to as television 20, sink device 22 will be referred to as amplifier 22, and sink device 24 will be referred to as projector 24.

[0061] 4, assume that the TV 20 is initially powered on, and the amplifier 22 and projector 24 are initially powered off. In this state, the TV 20 is the only active sink device, and video priority and audio priority are set for the HDMI port 15 connected to the TV 20. Therefore, the HDMI port 15 has the highest video priority, and the HDMI port 15 also has the highest audio priority. As a result, both the video signal and the audio signal are output from the HDMI port 15.

[0062] 5, the power supply of the amplifier 22 is turned on. With regard to audio, the television 20 supports only L-PCM, MPEG1, MP3, and MPEG2, whereas the amplifier 22 supports a variety of formats, such as AC-3 and MPEG-H3D in addition to L-PCM, MPEG1, MP3, and MPEG2. Therefore, the control unit 14 determines that the amplifier 22 has a higher priority than the television 20, and switches the output destination of the audio signal from the television 20 to the amplifier 22. With regard to video, because the television 20 has a higher resolution, the state in which the video signal is output to the television 20 is maintained.

[0063] 6, the projector 24 is powered on. The video format supported by the television 20 is 4K, the video format supported by the amplifier 22 is 2K, and the video format supported by the projector 24 is 8K. Therefore, the control unit 14 determines that the projector 24 has the highest priority and switches the output destination of the video signal from the television 20 to the projector 24. With regard to audio, the amplifier 22 supports a wider variety of formats than the projector 24 and the television 20, so the amplifier 22 is determined to have the highest priority and the state in which the audio signal is output to the amplifier 22 is maintained.

[0064] 7, the power to amplifier 22 is turned off. While television 20 supports four audio formats, projector 24 supports only one audio format. Therefore, control unit 14 determines that television 20 has a higher priority and switches the output destination of the audio signal from amplifier 22 to television 20.

[0065] As described above, in the video transmission system 100 according to this embodiment, the control unit 14 sets a video priority and an audio priority for the HDMI port that is actively connected among the HDMI ports 15, 16, and 17, and determines that the HDMI port with the highest video priority will be used to output the video signal, and determines that the port with the highest audio priority will be used to output the audio signal. For example, the control unit 14 sets the video priority so that the higher the resolution of the video format supported by the sink device, the higher the video priority, and sets the audio priority so that the greater the number of audio formats supported by the sink device, the higher the audio priority.

[0066] In the above configuration, video output and audio output are controlled so that a video signal is output to the active sink device with the highest resolution, and an audio signal is output to the active sink device that supports the most audio formats. This allows for more appropriate automatic switching, making it possible to connect any sink device to any HDMI port. As a result, user convenience is improved.

[0067] In the above-described embodiment, the video priority and audio priority are set based on the video format and audio format supported by each sink device. The method of setting the priority is not limited to the above-described example.

[0068] In one example, the user may manually set the priorities. In other words, the control unit 14 may set the priorities based on input from the user. Specifically, the control unit 14 may cause the television 20 to display a setting menu, for example. The setting menu allows the user to set video and audio priorities for the HDMI ports 15, 16, and 17.

[0069] In another example, the control unit 14 may set priorities such that the more recently the sink device was powered on, the higher the priority. In this example, the control unit 14 manages the power-on times for the sink devices 20, 22, and 24. For example, assume that the television 20 is powered on, then the amplifier 22 is powered on, and then the projector 24 is powered on, so that the television 20, the amplifier 22, and the projector 24 are all active. In this situation, the video priority and audio priority of the HDMI port 17 to which the projector 24 is connected are the highest, the video priority and audio priority of the HDMI port 16 to which the amplifier 22 is connected are the second highest, and the video priority and audio priority of the HDMI port 15 to which the television 20 is connected are the lowest. Therefore, the video signal and audio signal are output from the HDMI port 17. When projector 24 is powered off in this state, the HDMI port with the highest video priority and audio priority among the HDMI ports to which active sink devices are connected is HDMI port 16, and therefore, video and audio signals are output from HDMI port 16. If the active sink device does not support any video formats, control unit 14 may set the video priority of the HDMI port to which that sink device is connected to the lowest regardless of when the power was turned on. If the active sink device does not support any audio formats, control unit 14 may set the audio priority of the HDMI port to which that sink device is connected to the lowest regardless of when the power was turned on.

[0070] In yet another example, the control unit 14 may set priorities according to the usage time of the HDMI ports. In this example, the control unit 14 manages the usage time of the HDMI ports 15, 16, and 17. The usage time of an HDMI port may refer to the total time that the power of the sink device connected to that HDMI port is turned on. For example, the control unit 14 may set priorities such that the longer the usage time, the higher the priority.

[0071] Some of the above-described priority setting methods may be used in combination as appropriate. For example, if the priority cannot be determined by the methods described with reference to Figures 1 to 7, the priority may be determined using one of the above-described examples. For example, if two active sink devices support the same resolution, different video priorities cannot be set for these sink devices. In this case, a higher video priority may be set for the HDMI port connected to the sink device that was most recently turned on.

[0072] In the above-described embodiment, the video output and audio output are automatically switched in response to switching of the power supply of the sink device. In another embodiment, the control unit 14 may display a message to ask the user whether or not to switch the video output and / or audio output before switching the video output and / or audio output. In this case, the control unit 14 switches the video output and / or audio output in response to the user performing an operation to accept the switch using an interface such as a remote control.

[0073] Alternatively, after the video output and / or audio output has been automatically switched, the user may manually override the switching. In this case, the user may use an interface such as a remote control to instruct switching of the video output and / or audio output, and the control unit 14 switches the video output and / or audio output in response to the user's input.

[0074] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0075] 10...source device, 11...disk drive, 12...video signal output section, 13...audio signal output section, 14...control section, 141,142...priority setting section, 143,144...output control section, 15,16,17...HDMI port, 20,22,24...sink device, 21,23,25...HDMI cable, 100...video transmission system, 101...processor, 102...memory, 103...disk drive, 104...input / output interface, 800...video transmission system, 810...Blu-ray player, 811,812...HDMI port, 820...television, 830...AV amplifier, 840,850...HDMI cable.

Claims

1. a source device that provides content data including a video signal and an audio signal; a plurality of sink devices connected to the source device and capable of receiving the content data from the source device; Equipped with The source device is a plurality of ports for connecting the plurality of sink devices; a first priority setting unit that sets a video priority, which is a priority related to the video signal, for a port that is connected to an active port among the plurality of ports; a first output control unit that determines that the port having the highest video priority is to be used to output the video signal; a second priority setting unit that sets an audio priority, which is a priority related to the audio signal, for a port that is connected to an active port among the plurality of ports; a second output control unit that determines whether the port having the highest audio priority is to be used to output the audio signal; Equipped with Video transmission system.

2. the first priority setting unit sets the video priority such that the higher the resolution supported by the sink device, the higher the video priority; The video transmission system according to claim 1 .

3. the second priority setting unit sets the audio priority such that the greater the number of audio formats supported by the sink device, the higher the audio priority. The video transmission system according to claim 1 .

4. the plurality of ports are compliant with the HDMI (High Definition Multimedia Interface) standard and are connected to the plurality of sink devices via a plurality of HDMI cables, respectively; the first priority setting unit and the second priority setting unit recognize a video format and an audio format supported by each of the plurality of sink devices by receiving EDID (Extended Display Information Data) from the plurality of sink devices, the first priority setting unit sets the video priority based on the video format supported by each of the plurality of sink devices, and the second priority setting unit sets the audio priority based on the audio format supported by each of the plurality of sink devices. The video transmission system according to claim 1 .

5. A source device for providing content data including a video signal and an audio signal, comprising: a plurality of ports for connecting a plurality of sink devices capable of receiving the content data; a first priority setting unit that sets a video priority, which is a priority related to the video signal, for a port that is connected to an active port among the plurality of ports; a first output control unit that determines that the port having the highest video priority is to be used to output the video signal; a second priority setting unit that sets an audio priority, which is a priority related to the audio signal, for a port that is connected to an active port among the plurality of ports; a second output control unit that determines whether the port having the highest audio priority is to be used to output the audio signal; A source device comprising:

Images