JP5618534B2 - Communication device - Google Patents

Description

  The present invention relates to a communication device that transmits video data to an external device.

  Currently, a communication interface called High-Definition Multimedia Interface (HDMI) (registered trademark) has been proposed. A communication system compliant with the HDMI standard (hereinafter referred to as “HDMI system”) includes a source device and a sink device. The source device can transmit the video data via the HDMI interface. The sink device can receive the video data from the source device via the HDMI interface and display the received video data.

  In the HDMI system, a command compliant with the CEC (Consumer Electronics Control) standard (hereinafter referred to as “CEC command”) can be used. The source device can control the sink device by using the CEC command. The sink device can also control the source device by using the CEC command.

  The source device can acquire the physical address (Physical Address) assigned to the source device by the sink device from the EDID of the sink device (Patent Document 1).

JP 2007-202115 A

  Some CEC commands require the physical address of the source device. The <Active Source> command is one of CEC commands that require the physical address of the source device. When transmitting the <Active Source> command to the sink device, the source device needs to acquire the physical address assigned to the source device by the sink device.

  If the connection between the source device and the sink device is valid, the source device can obtain the EDID of the sink device from the sink device. In this case, the source device can acquire the physical address assigned to the source device from the EDID of the sink device, and can send an <Active Source> command to the sink device. The source device can determine whether or not the connection between the source device and the sink device is valid based on an HPD (Hot Plug Detect) signal transmitted from the sink device to the source device.

  When the sink device has a plurality of connection terminals (connectors), the physical address assigned to the source device can be changed to another physical address after the source device acquires the EDID of the sink device from the sink device There is sex. For example, when the source device A is connected to the connection terminal A and the physical address A (“1.0.0.0”) is assigned to the source device A, the source device B is connected to the connection terminal B. Consider an example. In this example, there is a possibility that a physical address B (“2.0.0.0”) different from the physical address A is assigned to the source device A, and the physical address A is assigned to the source device B. When the physical address of the source device A is changed from the physical address A to the physical address B, the source device A cannot correctly control the sink device until the physical address B is acquired from the sink device. For example, when an <Active Source> command including the physical address A is transmitted from the source device A to the sink device, the sink device selects the connection terminal B corresponding to the physical address A, and the video transmitted from the source device B Receive data. As a result, the sink device cannot display the video data transmitted from the source device A. Such a problem may also occur when a CEC command other than the <Active Source> command is transmitted to the sink device.

  Further, when the connection between the source device A and the sink device is not valid, the source device A cannot obtain the EDID of the sink device from the sink device. Therefore, when the connection between the source device A and the sink device is not valid, the source device A cannot transmit the <Active Source> command to the sink device. As a result, the source device A cannot select the connection terminal to which the source device A is connected to the sink device. Such a problem may also occur when a CEC command other than the <Active Source> command is transmitted to the sink device.

Accordingly, the present invention can be in the case of transmitting the video data to passing ShinSo placed et display equipment, reduce the possibility of selecting a connection terminal to which the display device is different device is connected The purpose is to do so.

A communication apparatus according to the present invention is a communication device, acquires the first device information before Symbol communication device comprises a first physical address corresponding to the connecting terminal of the display device connected from said display device a resulting unit preparative you, the first storage means for storing the device information, when the first device information into the storage means is stored, the first image generated on the basis of the device information First transmission means for transmitting data to the display device, and video data supplied from the first transmission means via the connection terminal of the display device to which the communication device is connected to the display device. the acquired from the display device after the connection is determined to be valid between the second transmitting means for transmitting a command for displaying on the display device to the display device, a pre-Symbol display device and the communication device To the means Or processing for causing the second transmission means to transmit the command including the second physical address included in the second device information acquired by the second device information, or between the display device and the communication device. characterized Rukoto which have a control means for controlling whether to perform a process to transmit the command containing the first physical address to the second transmission unit before the connection is determined to be valid And

According to the present invention, it is possible to when transmitting video data to a passing ShinSo placed et display equipment, reduce the possibility of selecting a connection terminal to which the display device is different device is connected .

1 is a system diagram showing an example of a communication system (HDMI system) according to Embodiments 1 and 2 of the present invention. It is a block diagram which shows an example of a structure of the communication apparatus 100 and the external apparatus 200 which concern on Example 1 and 2 of this invention. It is a flowchart for demonstrating the EDID acquisition process performed with the communication apparatus 100 which concerns on Example 1 and 2 of this invention. It is a flowchart for demonstrating the one touch play process (reproduction | regeneration video output process) performed with the communication system (HDMI system) which concerns on Example 1 of this invention. It is a flowchart for demonstrating the one touch play process (reproduction video output process) performed with the communication system (HDMI system) which concerns on Example 2 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. However, the following examples are merely examples, and the present invention is not limited to the following examples.

[Example 1]
FIG. 1 is a diagram illustrating an example of a communication system (HDMI system) according to the first embodiment of the present invention. FIG. 2 is a block diagram illustrating an example of the configuration of the communication device 100 and the external device 200 according to the first embodiment of the invention.

  As illustrated in FIGS. 1 and 2, the communication system according to the first embodiment includes a communication device 100, an external device 200, and a connection cable 300, and the communication device 100 and the external device 200 are connected via the connection cable 300. It is connected.

  In the first embodiment, the communication device 100, the external device 200, and the connection cable 300 are assumed to conform to the HDMI standard. Therefore, the communication device 100 functions as a source in the HDMI standard, the external device 200 functions as a sink in the HDMI standard, and the connection cable 300 functions as an HDMI cable in the HDMI standard. Note that the HDMI standard in Embodiments 1 and 2 is not limited to Version 1.3a, but may be Version 1.4a or later.

  In the first embodiment, the communication device 100 and the external device 200 are assumed to conform to the CEC (Consumer Electronics Control) standard defined by the HDMI standard. A command transmitted bidirectionally between the communication device 100 and the external device 200 conforms to the CEC standard. Hereinafter, a command conforming to the CEC standard is referred to as a “CEC command”.

  In the first embodiment, a video camera is used as an example of the communication device 100. The communication device 100 may be a still camera, a recorder, a DVD player, or the like as long as it is a video output device that can transmit video data, audio data, and auxiliary data to the external device 200 via the connection cable 300. It may be a device.

  In the first embodiment, a television receiver (hereinafter referred to as “TV”) is used as an example of the external device 200. The external device 200 is a device such as a projector or a personal computer as long as it is a display device that displays video data received from the communication device 100 on a display and outputs audio data received from the communication device 100 from a speaker. May be.

  Hereinafter, the communication device 100 is referred to as “video camera 100”, the external device 200 is referred to as “television 200”, and the connection cable 300 is referred to as “HDMI cable 300”.

<HDMI cable 300>
Next, the HDMI cable 300 will be described with reference to FIG.

  The HDMI cable 300 includes a + 5V power line, an HPD (Hot Plug Detect) line 301, and a DDC (Display Data Channel) line 302. The HDMI cable 300 further includes a TMDS (Transition Minimized Differential Signaling) line 303 and a CEC line 304.

  The + 5V power line is a power supply line for supplying + 5V from the video camera 100 to the television 200.

  The HPD line 301 is a transmission line for transmitting an H level (high voltage level) or L level (low voltage level) HPD signal from the television 200 to the video camera 100.

  The DDC line 302 is a transmission line for transmitting device information of the television 200 from the television 200 to the video camera 100. The device information of the television 200 is EDID (Extended display identification data) or E-EDID (Enhanced EDID) of the television 200. Both EDID and E-EDID are device information of the television 200. Both EDID and E-EDID include identification information of the television 200, image display capability of the television 200, a physical address, and the like. For example, EDID and E-EDID include information on resolution, scanning frequency, aspect ratio, color space, and the like supported by the television 200. E-EDID is an extension of EDID and includes more capability information than EDID. For example, the E-EDID includes information related to the format of video data and audio data supported by the television 200. Hereinafter, both EDID and E-EDID are referred to as “EDID”.

  The video camera 100 that has received the EDID of the television 200 can automatically know the image display capability, audio processing capability, and the like of the television 200 by analyzing the EDID of the television 200. Furthermore, the video camera 100 can automatically know the video format and audio format suitable for the image display capability and audio processing capability of the television 200. By setting the video camera 100 to a setting suitable for the television 200, the video camera 100 converts the video data and audio data transmitted from the video camera 100 to the television 200 to video data and audio data suitable for the capability of the television 200. Can be.

  The TMDS line 303 is a transmission line for transmitting video data, audio data, and auxiliary data from the video camera 100 to the television 200. The TMDS line 303 includes a TMDS channel 0, a TMDS channel 1, a TMDS channel 2, and a TMDS clock channel.

  The CEC line 304 is a transmission line for bidirectionally transmitting various CEC commands between the video camera 100 and the television 200. The television 200 can transmit a CEC command for controlling the video camera 100 to the video camera 100 via the CEC line 304. The video camera 100 can transmit a CEC command for controlling the television 200 to the television 200 via the CEC line 304.

<Video camera 100>
Next, an example of the configuration of the video camera 100 will be described with reference to FIG.

  As shown in FIG. 2, the video camera 100 includes a CPU (Central Processing Unit) 101, a memory 102, a communication unit 103, an imaging unit 104, a recording unit 105, a display unit 106, and an operation unit 107.

  The CPU 101 controls the entire operation of the video camera 100 according to a computer program stored in the memory 102. The CPU 101 can know the image display capability and sound processing capability of the television 200 by analyzing the EDID of the television 200 acquired from the television 200. Thereby, the CPU 101 can generate video data and audio data suitable for the image display capability and audio processing capability of the television 200.

  The memory 102 functions as a work area for the CPU 101. The memory 102 also stores the EDID of the television 200 (including the physical address of the video camera 100), information about the video camera 100, the result of analysis by the CPU 101, and the like. The work area of the CPU 101 is not limited to the memory 102 but may be an external recording device such as a hard disk device.

  The communication unit 103 has a connection terminal (connector) for connecting the HDMI cable 300. The communication unit 103 includes a connection detection unit 103a, a device information acquisition unit 103b, a data processing unit 103c, and a command processing unit 103d.

  The connection detection unit 103a can receive the HPD signal transmitted from the television 200 via the HPD line 301. When the connection detection unit 103a receives an H level HPD signal via the HPD line 301, the connection detection unit 103a notifies the CPU 101 that the H level HPD signal has been received. Similarly, when the connection detection unit 103 a receives an L-level HPD signal via the HPD line 301, the connection detection unit 103 a notifies the CPU 101 that the L-level HPD signal has been received.

  The device information acquisition unit 103b acquires the EDID of the television 200 from the television 200 via the DDC line 302 when the HPD signal detected by the connection detection unit 103a is at the H level. However, the device information acquisition unit 103b cannot acquire the EDID of the television 200 from the television 200 via the DDC line 302 when the HPD signal detected by the connection detection unit 103a is at the L level. When the EDID of the television 200 is acquired from the television 200, the device information acquisition unit 103b supplies the EDID of the television 200 to the CPU 101.

  The data processing unit 103 c can transmit video data, audio data, and auxiliary data to the television 200 via the TMDS line 303. Video data and audio data transmitted to the television 200 via the TMDS line 303 are suitable for the image display capability and audio processing capability of the television 200.

  When the operation mode of the video camera 100 is the shooting mode, the data processing unit 103c transmits the video data generated by the imaging unit 104 and the audio data generated by the microphone unit (not shown) via the TMDS line 303 to the television. 200 can be transmitted. In this case, auxiliary data generated by the CPU 101 is also transmitted to the television 200 via the TMDS line 303 together with video data and audio data. When the operation mode of the video camera 100 is the reproduction mode, the data processing unit 103c can transmit the video data and audio data reproduced from the recording medium 105a by the recording unit 105 to the television 200 via the TMDS line 303. In this case, auxiliary data generated by the CPU 101 is also transmitted to the television 200 via the TMDS line 303 together with video data and audio data.

  The command processing unit 103 d receives the CEC command transmitted from the television 200 via the CEC line 304, and transmits the CEC command generated by the CPU 101 for controlling the television 200 to the television 200 via the CEC line 304. To do. The CEC command received from the television 200 is supplied from the command processing unit 103d to the CPU 101, and the CPU 101 can control the video camera 100 according to the CEC command received from the television 200.

  When the video camera 100 transmits a CEC command to the television 200 and the television 200 can receive the CEC command from the video camera 100, the television 200 transmits a response signal to the CEC command to the video camera 100. Therefore, the command processing unit 103d can receive a response signal for the CEC command from the television 200. Response signals for the CEC command include an ACK (Acknowledge) signal (acknowledgement signal) indicating a positive response and a NACK (Negative Acknowledge) signal (negative response signal) indicating a negative response.

  When the operation mode of the video camera 100 is the shooting mode, the imaging unit 104 captures a subject and generates video data from the optical image of the subject. The video data generated by the imaging unit 104 may be a moving image or a still image. Video data generated by the imaging unit 104 is supplied from the imaging unit 104 to the data processing unit 103 c, the recording unit 105, and the display unit 106. When the EDID can be received from the television 200, the CPU 101 converts the video data supplied from the imaging unit 104 to the data processing unit 103c into video data suitable for the image display capability of the television 200. The video data supplied from the imaging unit 104 to the data processing unit 103 c is transmitted to the television 200 via the TMDS line 303. The video data supplied from the imaging unit 104 to the recording unit 105 is recorded on the recording medium 105a. The video data supplied from the imaging unit 104 to the display unit 106 is displayed on the display unit 106.

  When the operation mode of the video camera 100 is the shooting mode, the imaging unit 104 captures a subject and generates video data from the optical image of the subject. The video data generated by the imaging unit 104 may be a moving image or a still image. Video data generated by the imaging unit 104 is supplied from the imaging unit 104 to the data processing unit 103 c, the recording unit 105, and the display unit 106. When the EDID can be received from the television 200, the CPU 101 converts the video data supplied from the imaging unit 104 to the data processing unit 103c into video data suitable for the image display capability of the television 200. The video data supplied from the imaging unit 104 to the data processing unit 103 c is transmitted to the television 200 via the TMDS line 303. The video data supplied from the imaging unit 104 to the recording unit 105 is recorded on the recording medium 105a. The video data supplied from the imaging unit 104 to the display unit 106 is displayed on the display unit 106.

  When the imaging unit 104 generates video data, a microphone unit (not shown) generates audio data. The audio data generated by the microphone unit is supplied from the microphone unit to the data processing unit 103c, the recording unit 105, and a speaker unit (not shown). When EDID can be received from the television 200, the CPU 101 converts the audio data supplied from the microphone unit to the data processing unit 103c into audio data suitable for the audio processing capability of the television 200. The audio data supplied from the microphone unit to the data processing unit 103 c is transmitted to the television 200 via the TMDS line 303. The audio data supplied from the microphone unit to the recording unit 105 is recorded on the recording medium 105a. The audio data supplied from the microphone unit to the display unit 106 is output from the speaker unit.

  When the operation mode of the video camera 100 is the playback mode, the imaging unit 104 stops shooting the subject and stops generating video data from the optical image of the subject.

  When the operation mode of the video camera 100 is the shooting mode, the recording unit 105 can record the video data generated by the imaging unit 104 and the audio data generated by the microphone unit on the recording medium 105a. Recording of video data and audio data generated by the imaging unit 104 and the microphone unit on the recording medium 105 a is controlled by the CPU 101 in accordance with a user instruction input via the operation unit 107.

  When the operation mode of the video camera 100 is the reproduction mode, the recording unit 105 can reproduce the video data and audio data selected by the user from the recording medium 105a. Selection of video data and audio data reproduced from the recording medium 105 a is controlled by the CPU 101 in accordance with a user instruction input via the operation unit 107.

  Video data reproduced from the recording medium 105 a by the recording unit 105 is supplied from the recording unit 105 to the data processing unit 103 c and the display unit 106. When the EDID can be received from the television 200, the CPU 101 converts the video data supplied from the recording unit 105 to the data processing unit 103c into video data suitable for the image display capability of the television 200. The video data supplied from the recording unit 105 to the data processing unit 103 c is transmitted to the television 200 via the TMDS line 303. The video data supplied from the recording unit 105 to the display unit 106 is displayed on the display unit 106.

  The audio data reproduced by the recording unit 105 from the recording medium 105a is supplied from the recording unit 105 to the data processing unit 103c and a speaker unit (not shown). When the EDID can be received from the television 200, the CPU 101 converts the audio data supplied from the recording unit 105 to the data processing unit 103c into audio data suitable for the audio processing capability of the television 200. The audio data supplied from the recording unit 105 to the data processing unit 103 c is transmitted to the television 200 via the TMDS line 303. The audio data supplied from the recording unit 105 to the speaker unit is output from the speaker unit.

  The recording medium 105a is a recording medium such as a memory card or a hard disk device. The recording medium 105 a may be a recording medium built in the video camera 100 or a recording medium removable from the video camera 100.

  The display unit 106 includes a display device such as a liquid crystal display. When the operation mode of the video camera 100 is the shooting mode, the display unit 106 displays the video data generated by the imaging unit 104. When the operation mode of the video camera 100 is the reproduction mode, the display unit 106 displays the video data reproduced by the recording unit 105 from the recording medium 105a.

  The operation unit 107 provides a user interface for operating the video camera 100. The operation unit 107 includes a power button, a playback button, a mode switching button, and the like for operating the video camera 100, and each button includes a switch, a touch panel, and the like. The CPU 101 can control the video camera 100 in accordance with a user instruction input via the operation unit 107.

<TV 200>
Next, an example of the configuration of the television 200 will be described with reference to FIG.

  As illustrated in FIG. 2, the television 200 includes a CPU 201, a tuner unit 202, a communication unit 203, a display unit 204, an operation unit 205, and a memory 206.

  The CPU 201 controls the overall operation of the television 200 according to a computer program stored in the memory 206.

  The tuner unit 202 receives a television broadcast of the television channel selected by the user.

  The communication unit 203 has two or more connection terminals (connectors). One of the two or more connection terminals is connected to the HDMI cable 300. The communication unit 203 receives video data, audio data, and auxiliary data transmitted from the video camera 100 via the TMDS line 303. Video data received by the communication unit 203 from the video camera 100 is supplied to the display unit 204, and audio data received by the communication unit 203 from the video camera 100 is supplied to a speaker unit (not shown). The auxiliary data received by the communication unit 203 from the video camera 100 is supplied to the CPU 201.

  The communication unit 203 receives the CEC command transmitted from the video camera 100 via the CEC line 304, and sends the CEC command generated by the CPU 201 to the video camera 100 via the CEC line 304 for controlling the video camera 100. Send. The CEC command received from the video camera 100 is supplied from the communication unit 203 to the CPU 201. The CPU 201 can control the television 200 according to the CEC command received from the video camera 100.

  The communication unit 203 determines whether the video camera 100 is supplying + 5V to the television 200 via the + 5V power line. When + 5V is supplied from the video camera 100 to the television 200 via the + 5V power line, it is determined whether or not the EDID of the television 200 can be transmitted to the video camera 100. When the communication unit 203 can transmit the EDID of the television 200 to the video camera 100, the communication unit 203 transmits an H-level HPD signal to the video camera 100 via the HPD line 301. Further, when the EDID of the television 200 cannot be transmitted to the video camera 100, the communication unit 203 transmits an L level HPD signal to the video camera 100 via the HPD line 301. Even when + 5V is not supplied from the video camera 100 to the television 200, the communication unit 203 transmits an L-level HPD signal to the video camera 100 via the HPD line 301. Note that the EDID of the television 200 is stored in the memory 206.

  The communication unit 203 can transmit the EDID of the television 200 to the video camera 100 via the DDC line 302.

  Since the communication unit 203 has two or more connection terminals, the television 200 has the EDID of the television 200 for each connection terminal. The EDID of the television 200 corresponding to each connection terminal is stored in the memory 206. The EDID of the television 200 corresponding to each connection terminal includes a physical address assigned to the source device to which the television 200 is connected to the connection terminal. When one source device is connected to one connection terminal, the television 200 assigns a physical address to the source device. When two or more source devices are connected to two or more connection terminals, the television 200 assigns physical addresses to these source devices.

  The display unit 204 includes a display device such as a liquid crystal display. The display unit 204 can display video data supplied from at least one of the tuner unit 202 and the communication unit 203.

  The operation unit 205 provides a user interface for operating the television 200, and the CPU 201 can control the television 200 in accordance with a user instruction input via the operation unit 205. In addition, the operation unit 205 has a plurality of buttons for operating the television 200. Each button included in the operation unit 205 includes a switch, a touch panel, and the like.

<EDID acquisition processing>
Next, an EDID acquisition process performed by the video camera 100 will be described with reference to FIG.

  FIG. 3 is a flowchart for explaining EDID acquisition processing performed by the video camera 100 according to the first and second embodiments. The EDID acquisition process is a process for the video camera 100 to acquire the EDID of the television 200.

  The EDID acquisition process of FIG. 3 is a process performed when the video camera 100 supplies +5 V to the television 200 via the HDMI cable 300, for example. In the first and second embodiments, a case where the CPU 101 controls the EDID acquisition process of FIG. 3 according to a computer program stored in the memory 102 will be described.

  In step S301, the CPU 101 determines whether the HPD signal detected by the connection detection unit 103a has changed from the L level to the H level.

  When the HPD signal changes from the L level to the H level (YES in step S301), the CPU 101 determines that the EDID of the television 200 can be acquired from the television 200. In the case of YES in step S301, the flowchart proceeds from step S301 to step S302.

  When the HPD signal has not changed from the L level to the H level (NO in step S301), the CPU 101 determines that the EDID of the television 200 cannot be acquired from the television 200. If NO in step S301, the flowchart returns to step S301.

  In step S302, the CPU 101 instructs the device information acquisition unit 103b to acquire the EDID of the television 200 from the television 200. When the instruction indicating that the EDID of the television 200 is reacquired from the television 200 is received from the CPU 101, the device information acquisition unit 103 b acquires the EDID of the television 200 from the television 200 via the DDC line 302. Hereinafter, the EDID of the television 200 acquired by the device information acquisition unit 103b from the television 200 in step S302 is referred to as “first EDID”. Since the first EDID (first device information) includes the physical address assigned to the video camera 100 by the television 200, the CPU 101 can know the physical address assigned to the video camera 100 by the television 200. Hereinafter, the physical address of the video camera 100 included in the first EDID is referred to as a “first physical address”.

  In step S <b> 303, the CPU 101 stores the EDID of the television 200 acquired by the device information acquisition unit 103 b from the television 200 in the memory 102. The CPU 101 can know the video format and audio format suitable for the image display capability and audio processing capability of the television 200 by analyzing the first EDID. After the first EDID is stored in the memory 102, the flowchart returns from step S303 to S301.

<One-touch play process>
Next, a one-touch play process (reproduced video output process) performed in the communication system (HDMI system) according to the first embodiment will be described with reference to FIG.

  FIG. 4 is a flowchart for explaining one-touch play processing (reproduction video output processing) performed in the communication system (HDMI system) according to the first embodiment. The one touch play process of FIG. 4 is a process performed in order to implement One Touch Play described in the CEC standard.

  One Touch Play is a function of displaying video data on the display unit 204 of the television 200 when an instruction to request playback of video data selected by the user is input to the video camera 100. One Touch Play is realized by the video camera 100 controlling the television 200 using the CEC command. The <Image View On> command, the <Text View On> command, and the <Active Source> command are CEC commands for realizing One Touch Play. The <Image View On> command and the <Text View On> command are CEC commands that do not include the physical address of the source device, while the <Active Source> command is a command that includes the physical address of the source device.

  The <Image View On> command and the <Text View On> command are CEC commands for changing the state of the television 200 to a state where video data can be displayed on the display unit 204.

  The <Active Source> command is a CEC command for causing the television 200 to select a connection terminal corresponding to the physical address included in the <Active Source> command. When the <Active Source> command is received, the television 200 causes the display unit 204 to display video data from the source device connected to the connection terminal corresponding to the physical address included in the <Active Source> command. Therefore, the <Active Source> command is also a CEC command for requesting the television 200 to display the video data transmitted from the source device to the television 200 on the display unit 204.

  The one-touch play process in FIG. 4 is a process performed when, for example, the video camera 100 is in the playback mode and +5 V is supplied to the television 200 via the HDMI cable 300. In the first embodiment, a case where the CPU 101 controls the one-touch play process of FIG. 4 according to a computer program stored in the memory 102 will be described.

  In step S401, the CPU 101 determines whether or not an instruction to start one-touch play is given. In the first embodiment, it is determined whether or not the start of the one-touch play is instructed depending on whether or not the playback button in the operation unit 107 is pressed. However, the present invention is not limited to this. When determining that the playback button in the operation unit 107 has been pressed, the CPU 101 determines that an instruction to start one-touch play has been given (YES in step S401). If it is determined that the playback button in the operation unit 107 has not been pressed, the CPU 101 determines that the start of one-touch play has not been instructed (NO in step S401).

  If YES in step S401, the flowchart proceeds from step S401 to step S402. If NO in step S401, the flowchart returns to step S401.

  In step S402, the CPU 101 generates a <Polling Message> command. The <Polling Message> command is one of CEC commands. In the first embodiment, a <Polling Message> command is used to check whether or not the television 200 is a device compliant with the CEC standard. The <Polling Message> command generated by the CPU 101 is supplied to the command processing unit 103d. The command processing unit 103 d transmits a <Polling Message> command to the television 200 via the CEC line 304.

  When the <Polling Message> command from the video camera 100 cannot be received, the television 200 cannot transmit an ACK signal (acknowledgment signal) to the video camera 100. When the <Polling Message> command from the video camera 100 can be received, the television 200 determines whether or not the <Polling Message> command can be received. When the <Polling Message> command can be received, the television 200 transmits an ACK signal (acknowledgment signal) to the video camera 100. When the <Polling Message> command cannot be received, the television 200 does not transmit an ACK signal (acknowledgment signal) to the video camera 100 or transmits a NACK signal (negative acknowledgment signal) to the video camera 100.

  After the command processing unit 103d transmits the <Polling Message> command to the television 200, the flowchart proceeds from step S402 to step S403.

  In step S <b> 403, the CPU 101 determines whether the command processing unit 103 d has received an ACK signal for the <Polling Message> command from the television 200. The determination performed in step S403 is referred to as “first determination”.

  When the ACK signal for the <Polling Message> command can be received from the television 200 within a predetermined time, the command processing unit 103d notifies the CPU 101 that the ACK signal has been received from the television 200. In this case, CPU 101 determines that an ACK signal for the <Polling Message> command has been received from television 200 (YES in step S403). When YES is determined in the step S403, the CPU 101 determines that the television 200 is a device that conforms to the CEC standard. In the case of YES in step S403, the flowchart proceeds from step S403 to step S404.

  When the ACK signal for the <Polling Message> command cannot be received from the television 200 within a predetermined time, the command processing unit 103d notifies the CPU 101 that the ACK signal cannot be received from the television 200. In this case, CPU 101 determines that an ACK signal corresponding to the <Polling Message> command has not been received from television 200 (NO in step S403). If NO in step S403, the CPU 101 determines that the television 200 is not a device compliant with the CEC standard. If NO in step S403, the flowchart ends.

  In step S404, the CPU 101 generates a <Image View On> command (or <Text View On> command). The <Image View On> command (or <Text View On> command) generated by the CPU 101 is supplied to the command processing unit 103d. The command processing unit 103 d transmits the <Image View On> command (or <Text View On> command) to the television 200 via the CEC line 304. As described above, the <Image View On> command and the <Text View On> command are CEC commands that do not include the physical address of the video camera 100.

  The communication unit 203 receives the <Image View On> command (or <Text View On> command) via the CEC line 304. The <Image View On> command (or <Text View On> command) received by the communication unit 203 is supplied to the CPU 201. When the <Image View On> command (or <Text View On> command) is received from the communication unit 203, the CPU 201 changes the state of the television 200 to a state where the video data can be displayed on the display unit 204. When the <Image View On> command (or <Text View On> command) is received from the communication unit 203, the CPU 201 instructs the communication unit 203 to change the HPD signal from the L level to the H level. When the communication unit 203 changes the HPD signal from the L level to the H level, the television 200 can provide the latest EDID of the television 200 to the video camera 100.

  The communication unit 203 may fail to receive the <Image View On> command (or <Text View On> command). If reception of the <Image View On> command (or <Text View On> command) fails, the communication unit 203 cannot change the HPD signal from the L level to the H level. In step S405, the CPU 101 determines whether the HPD signal detected by the connection detection unit 103a is at the H level. The determination performed in step S405 is referred to as “second determination”.

  When the CPU 101 determines that the HPD signal is at the H level (YES in step S405), the CPU 101 determines that the connection between the video camera 100 and the television 200 is valid. If YES in step S405, the CPU 101 determines that the video camera 100 and the television 200 are in a connected state, and determines that the EDID of the television 200 can be acquired from the television 200. If YES in step S405, the CPU 101 instructs the counter 101a to reset the counter value T to zero. When receiving an instruction from the CPU 101 indicating that the counter value T is reset to 0, the counter 101a resets the counter value T to 0. In the case of YES in step S405, the flowchart proceeds from step S405 to step S406.

  When the CPU 101 determines that the HPD signal is at the L level (NO in step S405), the CPU 101 determines that the connection between the video camera 100 and the television 200 is not valid. If NO in step S <b> 405, the CPU 101 determines that the video camera 100 and the television 200 are not connected, and determines that the EDID of the television 200 cannot be acquired from the television 200. In the case of NO in step S405, the flowchart proceeds from step S405 to step S409.

  In step S406, the CPU 101 instructs the device information acquisition unit 103b to reacquire the latest EDID of the television 200 from the television 200. When the instruction indicating that the EDID of the television 200 is reacquired from the television 200 is received from the CPU 101, the device information acquisition unit 103 b acquires the EDID of the television 200 from the television 200 via the DDC line 302. Hereinafter, the latest EDID of the television 200 re-acquired from the television 200 by the device information acquisition unit 103b in step S406 is referred to as “second EDID”. Since the second EDID (second device information) includes the latest physical address assigned to the video camera 100 by the television 200, the CPU 101 knows the latest physical address assigned to the video camera 100 by the television 200. it can. Hereinafter, the physical address of the video camera 100 included in the second EDID is referred to as a “second physical address”. The CPU 101 deletes the first EDID from the memory 102 and stores the second EDID re-acquired from the television 200 by the device information acquisition unit 103 b in the memory 102. After the second EDID is stored in the memory 102, the flowchart proceeds from step S406 to step S407.

  Note that the EDID acquisition process performed in step S <b> 406 is performed even when the first EDID is already stored in the memory 102. This is because the first physical address included in the first EDID may not be the latest physical address assigned to the video camera 100.

  In step S407, the CPU 101 extracts the second physical address from the second EDID stored in the memory 102. After the CPU 101 extracts the second physical address from the second EDID, the flowchart proceeds from step S407 to step S408.

  In step S408, the CPU 101 generates an <Active Source> command including the second physical address. The <Active Source> command generated by the CPU 101 is supplied to the command processing unit 103d. The command processing unit 103 d transmits an <Active Source> command to the television 200 via the CEC line 304. After the command processing unit 103d transmits the <Active Source> command to the television 200, the flowchart proceeds from step S408 to step S414.

  The communication unit 203 receives an <Active Source> command via the CEC line 304. The <Active Source> command received by the communication unit 203 is supplied to the CPU 201. When the <Active Source> command is received from the communication unit 203, the CPU 201 extracts the second physical address from the <Active Source> command and selects a connection terminal corresponding to the second physical address. Here, since the second physical address is the latest physical address assigned to the video camera 100, the CPU 201 selects a connection terminal to which the video camera 100 is connected. After the connection terminal to which the video camera 100 is connected is selected, the CPU 201 instructs the communication unit 203 to validate the connection terminal to which the video camera 100 is connected. The communication unit 203 enables the connection terminal to which the video camera 100 is connected, and starts receiving video data, audio data, and auxiliary data from the video camera 100.

  In step S409, the CPU 101 instructs the counter 101a to add 1 to the counter value T. When receiving an instruction from the CPU 101 indicating that 1 is added to the counter value T, the counter 101a adds 1 to the counter value T. The counter value T indicates the number of times that the HPD signal is determined to be L level in step S405. After the counter 101a adds 1 to the counter value T, the flowchart proceeds from step S409 to step S410.

  In step S <b> 410, the CPU 101 compares the counter value T with the threshold value M recorded in the memory 102. The threshold value M indicates the number of times corresponding to a predetermined time (for example, 1 second to 10 seconds).

  When the counter value T is equal to or less than the threshold value M (NO in step S410), the flowchart returns from step S410 to step S404. Thus, the CPU 101 can determine whether or not the HPD signal has changed from the L level to the H level until a predetermined time has elapsed. When the HPD signal changes from the L level to the H level before the predetermined time elapses, the video camera 100 can transmit an <Active Source> command including the second physical address to the television 200.

  When the counter value T exceeds the threshold value M (YES in step S410), the flowchart proceeds from step S410 to step S411. If YES in step S410, the CPU 101 instructs the counter 101a to reset the counter value T to 0. When receiving an instruction from the CPU 101 indicating that the counter value T is reset to 0, the counter 101a resets the counter value T to 0.

  In step S <b> 411, the CPU 101 determines whether or not the first EDID is stored in the memory 102.

  When the CPU 101 determines that the first EDID is stored in the memory 102 (YES in step S411), the CPU 101 determines that the EDID of the television 200 has already been acquired from the television 200. However, the first EDID may not be the latest EDID of the television 200. In the case of YES in step S411, the flowchart proceeds from step S411 to step S412.

  When the CPU 101 determines that the first EDID is not stored in the memory 102 (NO in step S411), the CPU 101 determines that the EDID of the television 200 has not yet been acquired from the television 200. If NO in step S411, the flowchart ends. That is, if NO in step S411, the CPU 101 cannot generate an <Active Source> command. Therefore, the CPU 101 instructs the command processing unit 103d not to transmit the <Active Source> command to the television 200. As a result, the video camera 100 cannot transmit the <Active Source> command to the television 200.

  In step S <b> 412, the CPU 101 extracts the first physical address from the first EDID stored in the memory 102. However, since the first physical address is a physical address included in the first EDID, it may not be the latest physical address assigned to the video camera 100. After the CPU 101 extracts the first physical address from the first EDID, the flowchart proceeds from step S412 to step S413.

  In step S413, the CPU 101 generates an <Active Source> command including the first physical address. The <Active Source> command generated by the CPU 101 is supplied to the command processing unit 103d. The command processing unit 103 d transmits an <Active Source> command to the television 200 via the CEC line 304. After the command processing unit 103d transmits the <Active Source> command to the television 200, the flowchart proceeds from step S413 to step S414.

  The communication unit 203 receives an <Active Source> command via the CEC line 304. The <Active Source> command received by the communication unit 203 is supplied to the CPU 201. When the <Active Source> command is received from the communication unit 203, the CPU 201 extracts the first physical address from the <Active Source> command and selects the connection terminal corresponding to the first physical address. After the connection terminal corresponding to the first physical address is selected, the CPU 201 instructs the communication unit 203 to validate the connection terminal corresponding to the first physical address. The communication unit 203 validates the connection terminal corresponding to the first physical address, and starts receiving video data, audio data, and auxiliary data from the source device connected to the connection terminal. When the connection terminal corresponding to the first physical address is validated, the communication unit 203 changes the HPD signal from the L level to the H level. When the first physical address is the latest physical address assigned to the video camera 100, the CPU 201 selects a connection terminal to which the video camera 100 is connected. When the first physical address is the latest physical address assigned to the video camera 100, the communication unit 203 starts receiving video data, audio data, and auxiliary data from the video camera 100.

  In step S414, the CPU 101 instructs the recording unit 105 to reproduce the video data selected by the user or the video camera 100 and the audio data corresponding to the video data. The recording unit 105 reproduces the video data selected by the user or the video camera 100 and the audio data corresponding to the video data from the recording medium 105a. Video data and audio data reproduced from the recording medium 105a are supplied to the data processing unit 103c. The data processing unit 103 c transmits video data, audio data, and auxiliary data to the television 200 via the TMDS line 303. Video data and audio data reproduced from the recording medium 105a are also supplied to the display unit 106 and the speaker unit. The CPU 101 instructs the display unit 106 to display video data reproduced from the recording medium 105a, and instructs the speaker unit to output audio data reproduced from the recording medium 105a. The display unit 106 displays video data reproduced from the recording medium 105a. The speaker unit of the video camera 100 outputs audio data reproduced from the recording medium 105a.

  When the connection terminal to which the video camera 100 is connected is valid, the communication unit 203 receives the video data, audio data, and auxiliary data transmitted from the data processing unit 103 c via the TMDS line 303. The CPU 201 instructs the display unit 204 to display the video data received by the communication unit 203, and instructs the speaker unit to output the audio data received by the communication unit 203. The display unit 204 displays the video data received by the communication unit 203. The speaker unit of the television 200 outputs audio data received by the communication unit 203. The auxiliary data received by the communication unit 203 is supplied to the CPU 201.

  Thus, in the first embodiment, when the connection between the video camera 100 and the television 200 is valid, the video camera 100 can obtain the latest physical address assigned to the video camera 100 from the television 200. Yes (step S406). Thereby, the video camera 100 can transmit the <Active Source> command including the latest physical address to the television 200 (step S408). As a result, the television 200 can be prevented from selecting a connection terminal to which a source device other than the video camera 100 is connected, and the television 200 can display video data reproduced by the video camera 100. Yes (step S414).

  In the first embodiment, when the connection between the video camera 100 and the television 200 is not valid, the video camera 100 determines whether the HPD signal has changed to the H level until a predetermined time elapses. (Step S410). When the HPD signal changes to the H level before the predetermined time elapses, the video camera 100 can transmit an <Active Source> command including the latest physical address to the television 200 (step S408). . Accordingly, it is possible to reduce the possibility that the television 200 selects a connection terminal to which a source device other than the video camera 100 is connected, and the television 200 displays video data reproduced by the video camera 100. (Step S414).

  Further, in the first embodiment, when the connection between the video camera 100 and the television 200 is not valid, the video camera 100 can determine whether or not the first EDID is stored in the memory 102 (step). S411). If the first EDID is stored in the memory 102 (YES in step S411), the video camera 100 can transmit an <Active Source> command including the first physical address to the television 200 (step S41). S413). Thereby, when the first physical address is the latest physical address of the video camera 100, the television 200 can select a connection terminal to which the video camera 100 is connected (step S414). When the first physical address is the latest physical address of the video camera 100, the television 200 can display the video data reproduced by the video camera 100 (step S414).

  In the first embodiment, when the first EDID is not stored in the memory 102 (NO in step S411), the video camera 100 can also prevent the <Active Source> command from being transmitted to the television 200.

  Note that the process of transmitting the <Image View On> command (or <Text View On> command) to the television 200 may be performed in step S408 instead of step S404. In this case, the command processing unit 103 d transmits an <Active View> command to the television 200 after transmitting the <Image View On> command to the television 200.

  Further, the CEC command for realizing the One Touch Play function is not limited to the <Image View On> command, <Text View On> command, and <Active Source> command. The function of One Touch Play may be realized using a CEC command other than these CEC commands.

[Example 2]
Next, Example 2 will be described with reference to FIGS. In the second embodiment, description of the same parts as in the first embodiment is omitted, and different parts from the first embodiment are described.

  FIG. 5 is a flowchart for explaining one-touch play processing (reproduction video output processing) performed in the communication system (HDMI system) according to the second embodiment. The one-touch play process of FIG. 5 is also a process performed to realize the One Touch Play described in the CEC standard, similarly to the one-touch play process of FIG. The processes performed in steps S401 to S404 and S406 to S414 in the flowchart shown in FIG. 5 are the same as the processes performed in steps S401 to S404 and S406 to S414 in the flowchart shown in FIG. Therefore, in Example 2, description of steps S401 to S404 and S406 to S414 is omitted.

  The one-touch play process in FIG. 5 is a process performed when, for example, the video camera 100 is in the playback mode and +5 V is supplied to the television 200 via the HDMI cable 300. In the second embodiment, a case where the CPU 101 controls the one-touch play process of FIG. 5 according to a computer program stored in the memory 102 will be described.

  In step S501, the CPU 101 determines whether the HPD signal detected by the connection detection unit 103a is at the H level. The determination performed in step S501 is also referred to as “second determination” in the same manner as the determination performed in step S405.

  When the CPU 101 determines that the HPD signal is at the H level (YES in step S501), the CPU 101 determines that the connection between the video camera 100 and the television 200 is valid. If YES in step S <b> 501, the CPU 101 determines that the video camera 100 and the television 200 are connected, and determines that the EDID of the television 200 can be acquired from the television 200. If YES in step S501, the CPU 101 instructs the counter 101a to reset the counter value T to zero. When receiving an instruction from the CPU 101 indicating that the counter value T is reset to 0, the counter 101a resets the counter value T to 0. In the case of YES at step S501, the flowchart proceeds from step S501 to step S406.

  When the CPU 101 determines that the HPD signal is at the L level (NO in step S501), the CPU 101 determines that the connection between the video camera 100 and the television 200 is not valid. If NO in step S501, the CPU 101 determines that the video camera 100 and the television 200 are not connected, and determines that the EDID of the television 200 cannot be acquired from the television 200. In the case of NO in step S501, the flowchart proceeds from step S501 to step S502.

  In step S502, the CPU 101 generates a physical address request command. The physical address request command is a CEC command for requesting the television 200 the latest physical address assigned to the video camera 100 by the television 200. In the second embodiment, a case where the physical address request command is configured by a vendor command uniquely defined by the vendor of the video camera 100 will be described. The physical address request command generated by the CPU 101 is supplied to the command processing unit 103d. The command processing unit 103 d transmits a physical address request command to the television 200 via the CEC line 304.

  The communication unit 203 receives a physical address request command from the video camera 100 via the CEC line 304. The physical address request command received by the communication unit 203 is supplied to the CPU 201. When receiving a physical address request command from the communication unit 203, the CPU 201 reads the latest physical address assigned to the video camera 100 by the television 200 from the memory 206, and generates a physical address notification command including the physical address. The physical address notification command is a CEC command for notifying the video camera 100 of the latest physical address assigned to the video camera 100 by the television 200. In the second embodiment, a case where the physical address notification command is configured by a vendor command uniquely defined by the vendor of the video camera 100 will be described. The physical address notification command generated by the CPU 101 is supplied to the communication unit 203. The communication unit 203 transmits a physical address notification command to the video camera 100 via the CEC line 304.

  In step S503, the CPU 101 determines whether the command processing unit 103d has received a physical address notification command from the television 200. The determination performed in step S503 is referred to as “third determination”.

  When the physical address notification command can be received from the television 200 within a predetermined time, the command processing unit 103 d supplies the physical address notification command to the CPU 101. In this case, the CPU 101 determines that the physical address notification command has been received from the television 200 (YES in step S503). In the case of YES in step S503, the flowchart proceeds from step S503 to step S504.

  When the physical address notification command cannot be received from the television 200 within a predetermined time, the command processing unit 103d notifies the CPU 101 that the physical address notification command cannot be received from the television 200. In this case, the CPU 101 determines that the physical address notification command has not been received from the television 200 (NO in step S503). In the case of NO in step S503, the flowchart proceeds from step S503 to step S409.

  In step S504, the CPU 101 extracts the latest physical address assigned to the video camera 100 by the television 200 from the physical address notification command. Hereinafter, the latest physical address of the video camera 100 extracted from the physical address notification command in step S504 is referred to as a “third physical address”. The third physical address extracted from the physical address notification command is stored in the memory 102. After the third physical address is stored in the memory 102, the flowchart proceeds from step S504 to step S505.

  In step S505, the CPU 101 generates an <Active Source> command including the third physical address. The <Active Source> command generated by the CPU 101 is supplied to the command processing unit 103d. The command processing unit 103 d transmits an <Active Source> command to the television 200 via the CEC line 304. After the command processing unit 103d transmits the <Active Source> command to the television 200, the flowchart proceeds from step S505 to step S414.

  The communication unit 203 receives an <Active Source> command via the CEC line 304. The <Active Source> command received by the communication unit 203 is supplied to the CPU 201. When the <Active Source> command is received from the communication unit 203, the CPU 201 extracts the third physical address from the <Active Source> command and selects a connection terminal corresponding to the third physical address. Here, since the third physical address is the latest physical address assigned to the video camera 100, the CPU 201 selects a connection terminal to which the video camera 100 is connected. After the connection terminal to which the video camera 100 is connected is selected, the CPU 201 instructs the communication unit 203 to validate the connection terminal to which the video camera 100 is connected. The communication unit 203 enables the connection terminal to which the video camera 100 is connected, and starts receiving video data, audio data, and auxiliary data from the video camera 100. When the connection terminal to which the video camera 100 is connected is validated, the communication unit 203 changes the HPD signal from the L level to the H level.

  Thus, in the second embodiment, even when the connection between the video camera 100 and the television 200 is not valid, the video camera 100 acquires the latest physical address assigned to the video camera 100 from the television 200. (Step S504). Thereby, the video camera 100 can transmit the <Active Source> command including the latest physical address to the television 200 (step S505). As a result, the television 200 can be prevented from selecting a connection terminal to which a source device other than the video camera 100 is connected, and the television 200 can display video data reproduced by the video camera 100. Yes (step S414).

  In the second embodiment, steps S409 to S410 in FIG. 5 may be omitted. In this case, when NO in step S503, the flowchart of FIG. 5 proceeds from step S503 to S411.

  In the second embodiment, steps S409 to S413 in FIG. 5 may be omitted. In this case, if NO in step S503, the flowchart of FIG. 5 ends.

[Other embodiments]
The communication apparatus according to the present invention is not limited to the communication apparatus 100 described in the first and second embodiments. The communication device according to the present invention can be realized by a system including a plurality of devices, for example.

  The configurations and functions described in the first and second embodiments can also be realized by a computer program that can be executed by a computer (including a CPU (Central Processing Unit)). In this case, the computer program is read out from the computer-readable recording medium by the computer and executed by the computer. In this case, a hard disk device, an optical disk, a CD-ROM, a CD-R, a memory card, a ROM, or the like can be used as the computer-readable recording medium. The computer program may be provided from an external device to the computer via a communication interface and executed by the computer.

100 Communication device (source device)
101 CPU
DESCRIPTION OF SYMBOLS 102 Memory 103 Communication part 104 Imaging part 105 Recording part 105a Recording medium 106 Display part 107 Operation part 200 External apparatus (sink apparatus)
201 CPU
202 Tuner 203 Communication Unit 204 Display Unit 205 Operation Unit 206 Memory 300 Connection Cable (HDMI Cable)
301 HPD line 302 DDC line 303 TMDS line 304 CEC line

Claims (7)

A communication device,
Obtaining means for obtaining, from the display device, first device information including a first physical address corresponding to a connection terminal of a display device to which the communication device is connected;
Storage means for storing the first device information;
A first transmission unit configured to transmit video data generated based on the first device information to the display device when the first device information is stored in the storage unit;
Second transmitting means for transmitting a command to display the image data supplied from said first transmitting means through a connection terminal of the display device before Symbol communication device is connected to the display device ,
The command including the second physical address included in the second device information acquired from the display device by the acquisition unit after it is determined that the connection between the display device and the communication device is valid. The command including the first physical address is executed before it is determined that the connection between the display device and the communication device is valid or the processing for causing the second transmission means to transmit is performed. And a control unit that controls whether to perform processing for causing the second transmission unit to perform transmission. The control means determines whether or not the first device information is stored in the storage means before it is determined that the connection between the display device and the communication device is valid,
The control means causes the second transmission means to transmit the command including the first physical address in response to the storage of the first device information stored in the storage means. The communication apparatus according to claim 1.   The communication device according to claim 1, wherein the command is used to cause the display device to select a connection terminal of the display device corresponding to a physical address included in the command.   The first transmission unit is generated based on the second device information acquired from the display device by the acquisition unit after it is determined that the connection between the display device and the communication device is valid. 4. The communication device according to claim 1, wherein the transmitted video data can be transmitted to the display device. 5. The control means includes a third physical address included in a predetermined command transmitted from the display device to the communication device before it is determined that the connection between the display device and the communication device is valid. 5. The communication apparatus according to claim 1, wherein a process for causing the second transmission unit to transmit the command including the command is performed.   6. The communication apparatus according to claim 1, wherein the first device information includes information related to a display capability of the display apparatus.   The first device information is acquired from the display device by the acquisition unit before the second device information is acquired from the display device. The communication apparatus as described in.

Images