Communication apparatus and control method

A communication apparatus includes a display unit, a communication unit, and a control unit. The display unit displays video data. The communication unit communicates with an external apparatus. The control unit controls the communication apparatus in accordance with a command received by the communication unit. If the display unit is in a mute state and the communication unit is sending the external apparatus the data for placing the external apparatus in a mute state, the control unit determines not to control the communication apparatus in accordance with the command.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a communication apparatus used for sending video data to an external apparatus and a method of controlling the communication apparatus.

2. Description of the Related Art

In conventional communication systems, there are such systems that include a communication apparatus and an external display apparatus which are connected via a digital interface, and the communication apparatus is remote controlled by a remote control unit of the external display apparatus.

In a communication system discussed in Japanese Patent Application Laid-Open No. 2006-41584, by remote controlling a communication apparatus using a remote control unit of an external display apparatus, a user can view video data, reproduced from a recording medium, on the external display apparatus.

Generally, a distorted video image is displayed when power of a communication apparatus is turned on. In order to prevent such distorted image from being displayed on a monitor, a video image displayed on a monitor of a conventional communication apparatus is muted for a predetermined period of time. Further, when an operation mode of the communication apparatus is changed, a video image displayed on the monitor is also muted for a predetermined period of time.

Even when the video image displayed on the monitor of the communication apparatus is muted, if the remote control unit of the external display apparatus is operated, the communication apparatus receives a control command from the external display apparatus. If the command sent from the external display apparatus is executed in such a period, since the video displayed on the monitor of the communication apparatus is muted, the user is unable to determine whether the control command sent from the external display apparatus is executed.

If the user thinks that the communication apparatus is not executing the control command sent from the external display apparatus even if the communication apparatus is actually executing the control command, the user may operate the remote control unit again. If the user operates the remote control unit again, the operating state of the communication apparatus will be different from the state the user intended it to be, and an operational error is more likely to occur. As a result, an unexpected error may occur and the user may be confused.

SUMMARY OF THE INVENTION

The present invention is directed to prevent a operational error of a user and improve operability.

According to an aspect of the present invention, a communication apparatus includes a display unit that displays video data, a communication unit that communicates with an external apparatus, and a control unit that controls the communication apparatus in accordance with a command received by the communication unit, wherein the control unit determines not to control the communication apparatus in accordance with the command, if the display unit is in a mute state and the communication unit is sending the external apparatus data for placing the external apparatus in a mute state.

According to an aspect of the present invention, a method of controlling a communication apparatus, the communication apparatus including a display unit that displays video data, and a communication unit that communicates with an external apparatus, the method comprising: controlling the communication apparatus in accordance with a command received by the communication unit, and determining not to control the communication apparatus in accordance with the command, if the display unit is in a mute state and the communication unit is sending the external apparatus data for placing the external apparatus in a mute state.

DESCRIPTION OF THE EMBODIMENTS

Various exemplary embodiments, features, and aspects of the present invention will now be described in detail below with reference to the attached drawings.

First Embodiment

FIG. 1is a block diagram illustrating an example of a schematic configuration of a communication system according to a first exemplary embodiment of the present invention.FIG. 2illustrates an example of the communication system according to the first exemplary embodiment of the present invention.

As illustrated inFIGS. 1 and 2, the communication system according to the first exemplary embodiment includes a communication apparatus100, a connection cable300, an external apparatus200, and a remote control unit208. The communication apparatus100and the external apparatus200are connected via the connection cable300. The external apparatus200and the remote control unit208are connected via wireless communication.

The communication apparatus100is a video source that can send video data, audio data, and ancillary data to the external apparatus200via the connection cable300. The external apparatus200is an external display apparatus that displays the video data sent from the communication apparatus100on a display device, and outputs the audio data sent from the communication apparatus100from a speaker. The communication apparatus100and the external apparatus200can bidirectionally send various control commands via the connection cable300.

The remote control unit208is a user interface used for operating the communication apparatus100and the external apparatus200. The remote control unit208is configured such that it is capable of communicating with the external apparatus200via wireless communication but incapable of communicating with the communication apparatus100via wireless communication. The external apparatus200receives a remote control signal sent from the remote control unit208and analyzes the received remote control signal.

If the remote control signal received by the external apparatus200is a signal for controlling the external apparatus200, the external apparatus200is controlled in accordance with the received remote control signal. If the received remote control signal is a signal for controlling the communication apparatus100, the external apparatus200generates a control command that corresponds to the received remote control signal, and sends the generated control command to the communication apparatus100via the connection cable300. In this way, the user can directly remote control the external apparatus200using the remote control unit208. Further, the user can indirectly remote control the communication apparatus100using the remote control unit208.

According to the first exemplary embodiment, a video camera is used as an example of the communication apparatus100and a television receiving apparatus (hereinafter referred to as a “television”) is used as an example of the external apparatus200. Further, according to the first exemplary embodiment, a connection cable that conforms to the High-Definition Multimedia Interface (HDMI)® standard is used as an example of the connection cable300. The connection cable that conforms to the HDMI standard is hereinafter referred to as the “HDMI cable”.

Next, the HDMI cable300will be described. The HDMI cable300includes a Transition Minimized Differential Signaling (TMDS)® line301and a Consumer Electronics Control (CEC) line302. Further, the HDMI cable300includes a Hot Plug Detect (HPD) line, a Display Data Channel (DDC) line, and a power supply line.

The TMDS line301is a transmission line used for transmitting the video data, the audio data, and the ancillary data from the video camera100to the television200. The TMDS line301includes TMDS channel0, TMDS channel1, TMDS channel2, and TMDS clock channel. The CEC line302is a transmission line used for bidirectionally transmitting various control commands between the video camera100and the television200. The HPD line is a transmission line used for transmitting a HPD signal from the television200to the video camera100. The DDC line is a transmission line used for transmitting Extended Display Identification Data (EDID) of the television200from the television200to the video camera100. The EDID includes information on capability such as display capability of the television200. The power supply line is a line that supplies power from the video camera100to the television200.

The video camera100operates as a HDMI source defined by the HDMI standard. The television200operates as a HDMI sink defined by the HDMI standard. Further, the video camera100and the television200are HDMI devices that conform to the CEC standard. The CEC is a control protocol defined by the HDMI standard. A control command sent between the video camera100and the television200via the CEC line302will hereinafter be referred to as a “CEC command”.

The television200can control the video camera100by sending a CEC command used for controlling the video camera100to the video camera100via the CEC line302. The video camera100can also control the television200by sending a CEC command used for controlling the television200to the television200via the CEC line302. The CEC commands used for controlling the video camera100is, for example, a power on command, a power off command, a playback command, or a stop command. Further, the CEC command is, for example, a pause command, a fast forward command, a rewind command, a record command, a record pause command, a menu on command, or a menu off command.

The connection cable300is not limited to the HDMI cable. The connection cable300can be any connection cable other than the HDMI cable so long as it is a connection cable that separately includes a line that transmits the video data, the audio data, and the ancillary data and a line that bidirectionally transmits various control commands between the communication apparatus100and the external apparatus200.

Next, an example of a configuration of the video camera100will be described. As illustrated inFIG. 1, the video camera100includes a central processing unit (CPU)101, a random access memory (RAM)102, a recording unit103, a communication unit104, a data processing unit106, a command processing unit107, a display unit108, an operation unit109, an image capture unit111, and a read only memory (ROM)112.

The video camera100includes operation modes such as an image capture mode and a playback mode. If the video camera100is in the image capture mode, an image of an object can be captured by the video camera100and the captured image (either a moving image or a still image) can be recorded in a recording medium. If the video camera100is in the playback mode, a user selected image (either a moving image or a still image) can be reproduced from the recording medium.

The CPU101controls the operation of the video camera100in accordance with a computer executable program stored in the ROM112.

The RAM102is a memory that functions as a work area of the CPU101and is also used as a memory for storing various values, data, and information used by the CPU101. The CPU101acquires information on the television200from the television200via the HDMI cable300, and stores the acquired information in the RAM102. The information stored in the RAM102is, for example, a globally unique identifier (GUID), which is a unique identifier of the television200and the EDID of the television200. The work area of the CPU101is not limited to the RAM102and an external storage unit such as a hard disk apparatus can also be used.

If the video camera100is in the image capture mode, the image capture unit111senses an object and generates video data from an optical image of the object. The video data generated by the image capture unit111is supplied to the recording unit103, the display unit108, and the data processing unit106. Audio data generated by a microphone unit (not shown) will also be supplied to the recording unit103and the data processing unit106.

If the video camera100is in the image capture mode, the recording unit103can record the video data generated by the image capture unit111and the audio data generated by the microphone unit (not shown) in the recording medium.

Further, if the video camera100is in the playback mode, the recording unit103can reproduce the video data or the audio data selected by the user from the recording medium. The video data reproduced from the recording medium is supplied to the display unit108and the data processing unit106. On the other hand, the audio data reproduced from the recording medium is supplied to the data processing unit106and a speaker unit (not shown).

The recording medium used by the recording unit103can be either a recording medium integrated in the video camera100or a recording medium removable from the video camera100.

The communication unit104includes a HDMI terminal used for connecting the HDMI cable300. If the video camera100is in the image capture mode, the communication unit104transmits the video data generated by the image capture unit111, the audio data generated by the microphone unit (not shown), and the ancillary data generated by the CPU101to the television200via the TMDS line301. If the video camera100is in the playback mode, the communication unit104transmits the video data and the audio data which the recording unit103reproduced from the recording medium, and the ancillary data generated by the CPU101to the television200via the TMDS line301.

Further, the communication unit104includes a mute unit105. The mute unit105generates data used for placing the television200in a mute state. This data is hereinafter referred to as a mute instruction. The mute unit105sends the generated mute instruction to the television200via the TMDS line301. The mute instruction is sent from the mute unit105to the television200via the TMDS line301while a second mute process, which is described below, is being executed. The mute instruction is one of ancillary data transmitted via the TMDS line301.

Further, the communication unit104is capable of receiving the CEC command sent from the television200via the CEC line302. If the communication unit104receives the CEC command from the television200, the communication unit104supplies the received CEC command to the CPU101via the command processing unit107.

Furthermore, the communication unit104can also send the CEC command for controlling the television200to the television200via the CEC line302. The CEC command for controlling the television200is generated by the CPU101and supplied to the communication unit104via the command processing unit107.

If the video camera100is in the image capture mode, the data processing unit106supplies the video data generated by the image capture unit111, the audio data generated by the microphone unit (not shown), and the ancillary data supplied from the CPU101to the communication unit104. If the video camera100is in the playback mode, the data processing unit106supplies the video data and the audio data which the recording unit103reproduced from the recording medium as well as the ancillary data supplied from the CPU101to the communication unit104.

The display unit108includes a liquid crystal display. If the video camera100is in the image capture mode, the display unit108displays the video data generated by the image capture unit111. If the video camera100is in the playback mode, the display unit108displays the video data which the recording unit103reproduced from the recording medium.

Further, if the video camera100is in the mute state, the display unit108displays a mute image stored in the ROM112. According to the first exemplary embodiment, the mute image is video data that indicates that the video camera100is in the mute state. The mute image is, for example, black background image or blue background image. An icon or character information indicating that the video camera100is in the mute state can be included in the mute image. According to the first exemplary embodiment, if the display unit108is in the mute state, the mute image stored in the ROM112is displayed on the display unit108. However, the video camera100can be set so that the display unit108displays nothing in the mute state.

The operation unit109is a user interface for operating the video camera100. The operation unit109includes a plurality of buttons used for operating the video camera100. An instruction given by the user is sent to the CPU101via the operation unit109. Each button included in the operation unit109is configured by a switch or a touch panel.

The operation unit109includes buttons such as a power button, a start/stop button, a mode change button110, a menu button, a + button, a − button, and a SET button.

The power button is a button used for instructing the CPU101that the state of the video camera100is to be changed to a power on state or a power off state. The power on state is a state in which necessary power can be supplied to the whole video camera100from a power supply (not shown) such as a battery or an AC power supply. The power off state is a state in which supply of power from the power supply to a part or whole of the video camera100is stopped.

The start/stop button is a button used for instructing the CPU101that recording of the video data which has been generated by the image capture unit111to the recording medium is to be started or stopped. The mode change button110is a button used for instructing the CPU101that the operation mode of the video camera100is to be changed to a mode such as the image capture mode or the playback mode.

The menu button is a button used for instructing the CPU101to display or non display a menu screen of the video camera100. The menu screen of the video camera100includes a menu screen for controlling the video camera100and a menu screen for changing setting of the video camera100. These menu screens are stored in the ROM112.

In displaying the menu screen, the CPU101reads out the menu screen to be displayed from the ROM112and supplies the menu screen that has been read out to the display unit108and the data processing unit106. At this time, the CPU101superposes a cursor on the menu screen. The display unit108and the data processing unit106superposes the menu screen sent from the CPU101on the video data supplied from the image capture unit111or the recording unit103. In this way, a same menu screen is displayed on the display unit108and the television200.

If the menu screen is to be non displayed, the CPU101stops the supply of the menu screen to the display unit108and the data processing unit106.

The + button and the − button are used for moving the cursor on the menu screen. The SET button is used for instructing the CPU101to execute the item selected by the cursor. The + button, the − button, and the SET button are also used in changing the menu screens.

Further, the operation unit109includes a playback button, a stop button, a pause button, a fast forward button, and a rewind button. These buttons are used for instructing the CPU101to execute the playback, the stop, the pause, the fast forward, and the rewind operations of the video data recorded in the recording medium, respectively.

As described above, the mute image and the menu screens are stored in the ROM112. A plurality of icons used for notifying the user of the state of the video camera100are also stored in the ROM112. Further, a computer executable program used for controlling the operations of the video camera100is stored in the ROM112.

It is to be noted that the communication apparatus100is not limited to a video camera. For example, the communication apparatus100can be an image capture apparatus such as a video camera, a still camera, or a camera equipped cellular phone.

Next, an example of a configuration of the television200will be described. As illustrated inFIG. 1, the television200includes a CPU201, a tuner unit202, a communication unit203, a command processing unit204, a display unit205, a remote control receiving unit206, and a ROM207.

The CPU201controls operation of the television200according to a computer executable program stored in the ROM207.

The tuner unit202receives an analog television broadcast, a digital television broadcast, or a cable television broadcast in accordance with the user's selection. the television broadcast received by the tuner unit202can be selected by the remote control unit208. A television channel of the television broadcast received by the tuner unit202can also be selected by the remote control unit208. Video data included in the analog television broadcast, the digital television broadcast, or the cable television broadcast can be displayed on the display unit205. Further, audio data included in the analog television broadcast, the digital television broadcast, or the cable television broadcast can be output from a speaker unit (not shown).

The communication unit203includes a HDMI terminal used for connecting the HDMI cable300to the video camera100. The communication unit203is capable of receiving the video data, the audio data, and the ancillary data sent from the video camera100via the TMDS line301. The video data sent from the video camera100is displayed on the display unit205. The audio data sent from the video camera100is output from the speaker unit (not shown) Further, the ancillary data sent from the video camera100is supplied to the CPU201.

Further, the communication unit203is capable of receiving the CEC command sent from the video camera100via the CEC line302. If the communication unit203receives the CEC command sent from the video camera100, the communication unit203supplies the CEC command to the CPU201via the command processing unit204.

Further, the communication unit203is capable of sending a CEC command for controlling the video camera100to the video camera100via the CEC line302. The CEC command for controlling the video camera100is generated by the CPU201and supplied to the communication unit203via the command processing unit204.

The communication unit203receives the CEC command sent from the video camera100via the CEC line302. The CEC command sent from the video camera100is supplied from the communication unit203to the CPU201via the command processing unit204.

The CEC command for controlling the video camera100is generated by the CPU201and supplied to the communication unit203via the command processing unit204. The CEC command for controlling the video camera100is supplied from the command processing unit204to the communication unit203and transmitted to the video camera100via the CEC line302.

The display unit205includes a display device such as a liquid crystal display. The display unit205can display video data supplied from either the tuner unit202or the communication unit203. The display unit205can display the mute image stored in the ROM207.

When the remote control receiving unit206receives a remote control signal sent from the remote control unit208, the remote control receiving unit206supplies the received remote control signal to the CPU201. In this way, the instruction given by the user is sent to the CPU201via the remote control unit208and the remote control receiving unit206. The CPU201generates a CEC command that corresponds to the remote control signal sent from the remote control receiving unit206, and supplies the generated CEC command to the communication unit203via the command processing unit204. The CEC command supplied to the communication unit203is transmitted to the video camera100via the CEC line302. In this way, the user can remote control the video camera100using the remote control unit208.

As described above, the mute image and the menu screen are stored in the ROM207. A plurality of icons used for notifying the user of the state of the television200and the EDID of the television200are also stored in the ROM207. Further, a computer executable program used for controlling the operation of the television200is stored in the ROM207.

The remote control unit208is a user interface for operating the video camera100and the television200. The remote control unit208includes a plurality of buttons used for operating the video camera100and a plurality of buttons used for operating the television200. Each button of the remote control unit208is configured by a switch or a touch panel.

The remote control unit208includes a first power button, a television broadcast selection button, a channel button, an external input button, a menu button, a +(plus) button, a −(minus) button, and a SET button. These buttons are used for operating the television200.

The first power button is a button used for instructing the CPU201that the state of the television200is to be changed to a power on state or a power off state. The power on state is a state in which necessary power can be supplied to the whole television200from a power supply (not shown). The power off state is a state in which supply of power from the power supply to a part or whole of the television200is stopped.

The television broadcast selection button is used for selecting one broadcast out of the analog television broadcast, the digital television broadcast, and the cable television broadcast, and for instructing the CPU201to make the tuner unit202receive the selected television broadcast. The channel button is used for selecting a television channel of the broadcast which the tuner unit202receives.

The external input button is used for selecting either the video data received by the tuner unit202or the video data sent from the video camera100, and displaying the selected video data on the display unit205.

The menu button is used for instructing the CPU201to display or non display the menu screen of the television200. The menu screen of the television200includes a menu screen used for controlling the television200and a menu screen used for changing setting of the television200. These menu screens are stored in the ROM207.

In displaying the menu screen, the CPU201reads out the menu screen to be displayed from the ROM207and supplies the menu screen that has been read out to the display unit205. At this time, the CPU201superposes the cursor on the menu screen. The display unit205superposes the menu screen supplied from the CPU201on video data supplied from the tuner unit202or the communication unit203. In this way, a menu screen of the television200is displayed on the display unit205. If the menu screen is not to be displayed, the CPU201stops supplying the menu screen to the display unit205.

The + button and the − button are used for moving the cursor on the menu screen. The SET button is used for instructing the CPU201to execute the item selected by the cursor. The + button, the − button, and the SET button are also used in changing the menu screens.

If a menu screen of the video camera100is displayed on the television200, the + button, the − button, and the SET button can be used for operating the cursor on the menu screen. In this case, a CEC command that corresponds to the operation of the + button, the − button, and the SET button are sent from the television200to the video camera100via the CEC line302.

Further, the remote control unit208includes a second power button, a playback button, a stop button, a pause button, a fast forward button, a rewind button, a start/stop button, and a menu button. These buttons are used for operating the video camera100.

The second power button is used for instructing the CPU201to send the power on command or the power off command to the video camera100via the CEC line302. The power on command is a CEC command used for instructing the CPU101that the video camera100is to be changed to the power on state. The power off command is a CEC command used for instructing the CPU101that the video camera100is to be changed to the power off state.

The playback button, the stop button, and the pause button are buttons used for instructing the CPU201to send the playback command, the stop command, and the pause command to the video camera100via the CEC line302. Further, the fast forward button and the rewind button are buttons used for instructing the CPU201to send the fast forward command and the rewind command to the video camera100via the CEC line302. These commands are the CEC commands used for instructing the CPU101to execute playback, stop, pause, fast forward, and rewind of the video data recorded in the recording medium.

The start/stop button is used for instructing the CPU201to send the record command or the record pause command to the video camera100via the CEC line302. The record command is a CEC command used for instructing the CPU101to start recording the video data generated by the image capture unit111in the recording medium. The record pause command is a CEC command used for instructing the CPU101to temporarily stop the recording of the video data generated by the image capture unit111in the recording medium.

The menu button is used for instructing the CPU201to send a menu on command or a menu off command to the video camera100via the CEC line302.

The menu on command is a CEC command used for instructing the CPU101to display the menu screen of the video camera100. If the menu screen is to be displayed, the CPU101reads out the menu screen to be displayed from the ROM112and supplies the menu screen that has been read out to the display unit108and the data processing unit106. At this time, the CPU101superposes the cursor on the menu screen. The display unit108and the data processing unit106superposes the menu screen supplied from the CPU101on the video data supplied from the image capture unit111or the recording unit103. In this way, a same menu screen is displayed on the display unit108and the television200.

The menu off command is a CEC command used for instructing the CPU101not to display the menu screen of the video camera100. If the menu screen is not to be displayed, the CPU101stops supplying the menu screen to the display unit108and the data processing unit106. In this way, the television200can stop the display of the menu screen of the video camera100.

The external apparatus200is not limited to a television receiving apparatus and, for example, the external apparatus200can be a personal computer including a display.

Next, process executed by the video camera100when the operation mode of the video camera100is changed will be described referring toFIGS. 1,2, and3. The video camera100is connected to the television200via the HDMI cable300.

FIG. 3is a flowchart illustrating process executed by the video camera100when the operation mode of the video camera100, which is connected to the television200via the HDMI cable300, is changed. The process illustrated in the flowchart inFIG. 3is controlled by the CPU101executing a computer executable program stored in the ROM112.

In step S201, the CPU101determines whether the operation mode of the video camera100is changed. The operation mode of the video camera100is changed to the image capture mode or the playback mode when the user operates the mode change button110of the operation unit109.

If the operation mode of the video camera100is changed (YES in step S201), the process proceeds to step S202. If the operation mode of the video camera100is not changed (NO in step S201), then the process returns to step S201.

In step S202, the CPU101starts initialization process corresponding to the changed operation mode and starts executing the first mute process. The initialization process started in step S202includes various process necessary in appropriately operating the video camera100in accordance with the changed operation mode.

According to the first exemplary embodiment, the first mute process is process for placing the display unit108in the mute state. When the display unit108is in the mute state, the CPU101displays the mute image stored in the ROM112on the display unit108. If the execution of the first mute process is started, the CPU101continues to display the mute image on the display unit108until the execution of the first mute process is canceled in step S207or step S212.

After the execution of the first mute process is started in step S202, the process proceeds to step S203.

In step S203, the CPU101determines whether the video camera100and the television200are connected via the HDMI cable300.

If the CPU101determines that the video camera100and the television200are connected via the HDMI cable300(YES in step S203), the process proceeds to step S204. If the CPU101determines that the video camera100and the television200are not connected via the HDMI cable300(NO in step S203), then the process proceeds to step S211.

In step S204, the CPU101starts execution of the second mute process.

According to the first exemplary embodiment, the second mute process is process for placing the television200in the mute state by sending the mute instruction from the mute unit105to the television200via the TMDS line301. If the execution of the second mute process is started, the CPU101controls the mute unit105so that the mute instruction is continuously transmitted to the television200until the execution of the second mute process is canceled in step S208. In this case, the CPU101controls the data processing unit106and the communication unit104so that the mute image and silent data stored in the ROM112are continuously transmitted to the television200until the execution of the second mute process is cancelled in step S208. The mute image and the silent data stored in the ROM112are transmitted to the television200via the TMDS line301.

While receiving the mute instruction from the video camera100, the television200displays the mute image stored in the ROM207on the display unit205. Further, while receiving the mute instruction from the video camera100, the television200mutes the sound output from the speaker unit (not shown). In this way, while the second mute process is being executed, the television200executes the mute process as does the video camera100.

Not only the mute instruction the but also mute image and the silent data are sent to the television200because the television200can be an apparatus incapable of executing the mute instruction. If the television200is incapable of executing the mute instruction, the television200displays the mute image received from the video camera100on the display unit205. Further, in this case, the television200outputs the silent data received from the video camera100from the speaker unit (not shown).

After the execution of the second mute process is started in step S204, the process proceeds to step S205.

In step S205, the CPU101determines whether the CEC command used for controlling the video camera100is received from the television200. The CEC command used for controlling the video camera100is transmitted from the television200to the video camera100via the CEC line302. When the communication unit104receives the CEC command used for controlling the video camera100from the television200, the communication unit104supplies the CEC command to the command processing unit107. The command processing unit107supplies the CEC command supplied from the communication unit104to the CPU101. In this way, the CPU101can determine whether the CEC command used for controlling the video camera100and sent from the television200is received.

If the CPU101receives the CEC command for controlling the video camera100from the television200(YES in step S205), then the process proceeds to step S209. If the CPU101does not receive the CEC command for controlling the video camera100from the television200(NO in step S205), then the process proceeds to step S206.

In step S206, the CPU101determines whether the initialization process is completed. If the CPU101determines that the initialization process is completed (YES in step S206), then the process proceeds to step S207. If the CPU101determines that the initialization process is not yet completed (NO in step S206), then the process returns to step S205.

In step S207, the CPU101cancels the execution of the first mute process. If the execution of the first mute process is canceled, the process of displaying the mute image on the display unit108ends. If the current operation mode is the image capture mode, the CPU101displays the video data generated by the image capture unit111on the display unit108when the execution of the first mute process is canceled. If the current operation mode is the playback mode, the CPU101instructs the display unit108to display the menu screen used for selecting the video data recorded in the recording medium when the execution of the first mute process is canceled.

When the execution of the first mute process is canceled in step S207, the process proceeds to step S208.

In step S208, the CPU101cancels the execution of the second mute process. If the execution of the second mute process is canceled, a “mute period” ends. The mute period is a period in which the mute image is displayed on the display unit108and on the display unit205of the television200. If the execution of the second mute process is canceled, the CPU101ends the mute instruction and the process of sending the mute image and the silent data to the television200. Then, the CPU101starts the process of sending the same video data as the one displayed on the display unit108to the television200. As a result, the same video image is displayed on the display unit108and the television200.

When the execution of the second mute process is canceled in step S208, the process returns to step S201.

In step S209, the CPU101determines whether the CEC command received in step S205is a power off command.

If the CEC command received in step S205is not the power off command (NO in step S209), then the process proceeds to step S213. If the CEC command received in step S205is determined as the power off command (YES in step S209), then the process proceeds to step S210.

In step S213, the CPU101does not execute the CEC command received in step S205and ignores the CEC command. In this way, even if the CPU101receives a CEC command other than the power off command from the television200during the initialization process, the CEC command is not executed.

When the CEC command received in step S205is ignored in step S213, the process returns to step S206.

In step S210, the CPU101executes the power off command. In this way, the state of the video camera100is changed to the power off state. After then, the process ends.

In step S211, the CPU101determines whether the initialization process is completed. If the CPU101determines that the initialization process is completed (YES in step S211), the process proceeds to step S212. If the CPU101determines that the initialization process is not yet completed (NO in step S211), then step S211is repeated.

In step S212, the CPU101cancels the execution of the first mute process. If the execution of the first mute process is cancelled, process of displaying the mute image on the display unit108ends. If the current operation mode is the image capture mode, when the execution of the first mute process is cancelled, the CPU101displays the video data generated by the image capture unit111on the display unit108. If the current operation mode is the playback mode, when the execution of the first mute process is cancelled, the CPU101displays the menu screen used for selecting the video data recorded in the recording medium on the display unit108.

When the execution of the first mute process is cancelled in step S212, the process returns to step S201.

In this way, the video camera100in accordance with the first exemplary embodiment can be configured not to execute a CEC command other than the power off command until a certain period of time passes from when the operation mode is changed even if the remote control unit208is operated. In this way, while the display unit108and the television200display the mute image, a problem that may occur due to the execution of the CEC command other than the power off command by the video camera100can be prevented. As a result, the operating state of the video camera100matches the user intended operating state, and accordingly, misuse can be prevented and operability can be improved. Further, since possibility of an unexpected operation can be reduced, the possibility of the user being confused can also be reduced.

Further, since the video camera100cancels the first and the second mute process after the initialization process is completed according to the first exemplary embodiment, distorted video is not displayed on either the display unit108or the display unit205.

Further, according to the first exemplary embodiment, the image capture mode and the playback mode of the video camera100are described as examples of the operation mode, however, the modes are not limited to such modes. For example, the image capture mode can be replaced with a moving image capture mode for capturing a moving image or a still image capture mode for capturing a still image. Similarly, the playback mode can be replaced with a moving image playback mode for reproducing a moving image or a still image playback mode for reproducing a still image.

Next, referring toFIGS. 1,2, and4, the process of the video camera100that is executed when the state of the video camera100which is connected to the television200via the HDMI cable300is changed to a power on state will be described.

FIG. 4is a flowchart illustrating process executed by the video camera100when the mode of the video camera100, which is connected to the television200via the HDMI cable300, is changed to the power on mode. The process illustrated in the flowchart inFIG. 4is controlled by the CPU101executing a computer executable program stored in the ROM112.

In step S401, the CPU101determines whether the video camera100is changed to the power on state when the user operates the power button of the operation unit109.

If the video camera100is changed to the power on state (YES in step S401), then the process proceeds to step S402. If the video camera100is not changed to the power on state (NO in step S401), then the process returns to step401.

In step S402, the CPU101starts the initialization process corresponding to the current operation mode and starts executing the first mute process. The initialization process started in step S402includes various process necessary in appropriately operating the video camera100in accordance with the current operation mode.

If the execution of the first mute process is started, the CPU101continues to display the mute image on the display unit108until the execution of the first mute process is canceled in step S407or step S412.

After the execution of the first mute process is started in step S402, the process proceeds to step S403. In step S403, the CPU101determines whether the video camera100and the television200are connected via the HDMI cable300.

If the CPU101determines that the video camera100and the television200are connected via the HDMI cable300(YES in step S403), the process proceeds to step S404. If the CPU101determines that the video camera100and the television200are not connected via the HDMI cable300(NO in step S403), then the process proceeds to step S411.

In step S404, the CPU101starts execution of the second mute process. If the execution of the second mute process is started, the CPU101controls the mute unit105so that the mute instruction is continuously transmitted to the television200from the video camera100until the execution of the second mute process is canceled in step S408. Further, if the execution of the second mute process is started, the CPU101controls the data processing unit106and the communication unit104so that the mute image stored in the ROM112is continuously transmitted to the television200via the TMDS line301until the execution of the second mute process is cancelled in step S408. At this time, the silent data stored in the ROM112is transmitted to the television200together with the mute data.

If the television200receives the mute instruction from the video camera100, the television200displays the mute image stored in the ROM207on the display unit205for a predetermined period of time. Further, in this case, the television200mutes the sound output from the speaker unit (not shown) for a predetermined period of time. In this way, while the second mute process is being executed, the television200executes the mute process as does the video camera100.

Not only the mute instruction but also the mute image and the silent data are sent to the television200because the television200can be an apparatus which cannot process the mute instruction. If the television200is cannot process the mute instruction, the television200displays the mute image received from the video camera100via the TMDS line301on the display unit205. Further, in this case, the television200outputs the silent data received from the video camera100via the TMDS line301from the speaker unit (not shown).

After the execution of the second mute process is started in step S404, the process proceeds to step S405.

In step S405, the CPU101determines whether the CEC command used for controlling the video camera100is received from the television200. The CEC command used for controlling the video camera100is transmitted from the television200to the video camera100via the CEC line302. When the communication unit104receives the CEC command used for controlling the video camera100from the television200, the communication unit104supplies the CEC command to the command processing unit107. The command processing unit107supplies the CEC command supplied from the communication unit104to the CPU101. In this way, the CPU101can determine whether the CEC command used for controlling the video camera100and sent from the television200is received.

If the CPU101receives the CEC command for controlling the video camera100from the television200(YES in step S405), then the process proceeds to step S409. If the CPU101does not receive the CEC command for controlling the video camera100from the television200(NO in step S405), then the process proceeds to step S406.

In step S406, the CPU101determines whether the initialization process is completed. If the CPU101determines that the initialization process is completed (YES in step S406), then the process proceeds to step S407. If the CPU101determines that the initialization process is not yet completed (NO in step S406), then the process returns to S405.

In step S407, the CPU101cancels the execution of the first mute process. If the execution of the first mute process is canceled, the process of displaying the mute image on the display unit108ends. If the current operation mode is the image capture mode, the CPU101displays the video data generated by the image capture unit111on the display unit108when the execution of the first mute process is canceled. If the current operation mode is the playback mode, the CPU101instructs the display unit108to display the menu screen used for selecting the video data recorded in the recording medium when the execution of the first mute process is canceled.

When the execution of the first mute process is canceled in step S407, the process proceeds to step S408. In step S408, the CPU101cancels the execution of the second mute process. If the execution of the second mute process is canceled, a “mute period” ends. The mute period is a period in which the mute image is displayed on the display unit108and on the television200. If the execution of the second mute process is canceled, the CPU101ends the mute instruction and the process of sending the mute image and the silent data to the television200. Then, the CPU101starts the process of sending the same video data as the one displayed on the display unit108to the television200. As a result, the same video image is displayed on the display unit108and the television200in the mute period.

When the execution of the second mute process is canceled in step S408, the process ends.

In step S409, the CPU101determines whether the CEC command received in step S405is a power off command.

If the CEC command received in step S405is not the power off command (NO in step S409), then the process proceeds to step S413. If the CEC command received in step S405is determined as the power off command (YES in step S409), then the process proceeds to step S410.

In step S413, the CPU101does not execute the CEC command received in step S405and ignores the CEC command. In this way, even if the CPU101receives a CEC command other than the power off command from the television200during the initialization process, the CEC command is not executed.

When the CEC command received in step S405is ignored in step S413, the process proceeds to step S406.

In step S410, the CPU101executes the power off command. In this way, the state of the video camera100is changed to the power off state. After then, the process ends.

In step S411, the CPU101determines whether the initialization process is completed.

If the CPU101determines that the initialization process is completed (YES in step S411), the process proceeds to step S412. If the CPU101determines that the initialization process is not yet completed (NO in step S411), then step S411is repeated.

In step S412, the CPU101cancels the execution of the first mute process. If the execution of the first mute process is cancelled, process of displaying the mute image on the display unit108ends. If the current operation mode is the image capture mode, when the execution of the first mute process is cancelled, the CPU101displays the video data generated by the image capture unit111on the display unit108. If the current operation mode is the playback mode, when the execution of the first mute process is cancelled, the CPU101displays the menu screen used for selecting the video data recorded in the recording medium on the display unit108.

The process ends when the execution of the first mute process is cancelled in step S412.

In this way, the video camera100according to the first exemplary embodiment can be configured not to execute a CEC command other than the power off command until a certain period of time passes from when the power of the video camera100is turned on even if the remote control unit208is operated. In this way, while the display unit108and the television200are displaying the mute image, a problem that may occur due to the execution of the CEC command other than the power off command by the video camera100can be prevented. As a result, the operating state of the video camera100matches an operating state intended by the user, and accordingly, misuse can be prevented and operability can be improved. Further, since possibility of an unexpected operation can be reduced, the possibility of the user being confused can also be reduced.

Further, since the video camera100cancels the first and the second mute process after the initialization process is completed according to the first exemplary embodiment, distorted video is not displayed on either the display unit108or the television200.

Second Embodiment

Next, a second exemplary embodiment of the present invention will be described referring toFIG. 5. In the second exemplary embodiment, description of components similar to those of the first exemplary embodiment will be omitted and only the components different from the first exemplary embodiment will be described.

A selection screen501is one of the menu screens displayed on the display unit108, and stored in the ROM112. The selection screen501is displayed on the display unit108when the user operates the operation unit109. The user can select whether to make the video camera100execute the process described in the first exemplary embodiment or different process by operating the selection screen501.

The selection screen501includes an ON button502and an OFF button503. When the user operates the + button506or the − button505of the operation unit109, the ON button502or the OFF button503is selected by the cursor of the selection screen501. The − button505is used for moving the cursor on the selection screen501to the left, whereas the + button506is used for moving the cursor on the selection screen501to the right.

If the user presses the SET button504while the ON button502is selected by the cursor, the CPU101turns on a constant CEC command execution function. If the constant CEC command execution function is turned on, the CPU101stores a flag indicating that the constant CEC command execution function is turned on in the RAM102. If the constant CEC command execution function is turned on, even if the first mute process and the second mute process is being executed, the video camera100can execute a CEC command other than the power off command. In other words, if the constant CEC command execution function is turned on, the video camera100executes process different from the one described in the first exemplary embodiment.

If the user presses the SET button504while the OFF button503is selected by the cursor, the CPU101turns off the constant CEC command execution function. If the constant CEC command execution function is turned off, the CPU101stores a flag indicating that the constant CEC command execution function is turned off in the RAM102. If the constant CEC command execution function is turned off, the video camera100does not execute a CEC command other than the power off command when the first mute process and the second mute process are being executed. In other words, if the constant CEC command execution function is turned off, the video camera100executes the process described in the first exemplary embodiment.

In this way, according to the second exemplary embodiment, the user can select whether to make the video camera100execute the process described in the first exemplary embodiment.

The communication apparatus according to the present invention is not limited to the communication apparatus described in the first and the second exemplary embodiments. For example, the communication apparatus100according to the present invention can be a system including a plurality of apparatuses.

Further, various functions and process described in the first and the second exemplary embodiments can be realized by a computer (including a CPU) which executes a computer executable program. In this case, the computer executable program realizes the various functions described in the first and the second exemplary embodiments.

The computer executable program according to the present invention can realize the various functions and process described in the first and the second exemplary embodiments using an operating system (OS) running on the computer.

The computer executable program according to the present invention is read out from a computer readable recording medium and executed by the computer. The computer readable recording medium is, for example, a hard disk, an optical disk, a CD-ROM, a CD-R, a memory card, and a ROM. Further, the computer executable program according to the present invention can be supplied from an external apparatus to the computer via a communication interface, and executed by the computer.

This application claims priority from Japanese Patent Application No. 2008-171733 filed Jun. 30, 2008, which is hereby incorporated by reference herein in its entirety.