JP4420448B2 - Communication apparatus and control method - Google Patents

Description

  The present invention relates to a communication device and a control method thereof.

  A conventional digital video camera is configured to record and reproduce data in a plurality of video formats such as HD (High Definition), SD (Standard Definition), SDL (Standard Definition Long), etc. (for example, Non-patent document 1). Currently, a compression format corresponding to a plurality of different compression methods, for example, a DV (Digital Video) format or a method of recording MPEG-2 video data on the same recording medium (for example, on the same tape) has been proposed. In this case, for example, SD format video data (referred to as SD video data) is recorded in the DV format, and HD format video data (referred to as HD video data) is recorded in the MPEG-2 format (for example, Patent Documents). 1).

  A case of reproducing a tape in which a plurality of formats are recorded will be described with reference to FIG. In FIG. 1, a DVC (digital video camera) 101 is connected to a PC (personal computer) 103 via an IEEE 1394 cable 102 which is a communication cable compliant with the IEEE 1394 standard (see Non-Patent Documents 2 and 3). Here, the IEEE 1394 standard is a standard related to a serial bus. FIG. 11 is a diagram showing a recording state of video data on the magnetic tape 105 housed in the DVC 101. As shown in FIG. 11, DV video data 1101 and 1103 and MPEG-2 video data 1102 are alternately recorded. The DVC 101 connected to the PC 103 with the IEEE 1394 cable 102 as shown in FIG. 1 is controlled to be played back, stopped, etc. by various control commands from the editing application on the PC 103 (see Non-Patent Document 4).

  During the reproduction operation, the DVC 101 outputs the reproduced DV video data as isochronous data from the IEEE 1394 terminal when reproducing the DV video data 1101 of FIG. When the MPEG-2 video data 1102 is being reproduced, the reproduced MPEG-2 format video data is output as isochronous data from the IEEE 1394 terminal. The PC 103 captures and edits the isochronous data.

  At this time, the PC 103 can know whether the video format being played back by the DVC 101 is the DV format or the MPEG-2 format by using a status command of “Output Plug Signal Format” (see Non-Patent Document 5). reference). Here, Plug refers to a plug defined in Non-Patent Document 6. The plug includes an input plug and an output plug, both of which are logically configured. The input plug is managed by the input plug control register (iPCR), and the output plug is managed by the output plug control register (oPCR). In addition, since detailed description of iPCR and oPCR is described in Non-Patent Document 6, it is omitted. In the above case, when the PC 103 inquires of the output format to the DVC 101 using the status command of OutputPlug Signal Format, whether the output format of the data being reproduced and output by the DVC 101 is, for example, the DV system or the MPEG-2 system In response to the OutputPlug Signal Format control command.

  Further, when capturing a camera image, it is possible to specify that the DVC 101 is to output the DV or MPEG-2 format from the plug by the output plug signal format control command.

Further, in the DVC 101, the format output from the interface can be fixed to an arbitrary format. This is to prevent data in a format not supported by the receiving apparatus (PC 103) from being output when, for example, dubbing or the like is performed and the tape 105 having a mixed format is reproduced. FIG. 12 shows the relationship between data on the magnetic tape 105 and output data in this case. In FIG. 12, DV video data 1101 and 1103 and MPEG-2 video data 1102 are recorded on the magnetic tape 105 shown in FIG. On the other hand, FIG. 12B shows a data output state when the output format is fixed to the DV system. As shown in (b), data is not output when a portion where MPEG-2 video data 1102 is recorded is being reproduced. In this case, the output is fixed to the DV system when the receiving side apparatus can only receive DV format video data, but the output is fixed to MPEG-2 when the receiving side apparatus can only receive MPEG-2. It is also possible to do.
Specificationsof Consumer-Use Digital VCRs using 6.3mm magnetic tape IEEE Std1394-1995, IEEE Standard for a High Performance Serial Bus, Institute of Electrical and Electronics Engineers, Inc. IEEE Std 1394a-2000, IEEE Standard for a High Performance Serial Bus-Amendment 1, Institute of Electrical and Electronics Engineers, Inc. AV / C Tape Recorder / Player SubunitSpecification, 1394 Trade Association AV / C Digital Interface Command Set General Specification Version 4.1, 1394 Trade Association IEC 61883-1, Consumer audio / video equipment-Digital interface-Part 1: General JP 2001-275076 A

  In the above configuration, the DVC 101 is connected to the PC 103 in a state in which the DVC 101 is set to the output format of either the DV system or the MPEG-2 system, and the application of the PC 103 can support data of any system. Suppose. In this case, the DVC 101 transmits only the data in the output format that happened to be fixed. For this reason, although the PC 103 can receive data of any output format, it cannot receive video data other than the fixed output format.

  The present invention has been made in view of the above problems, and outputs an external device before receiving data from an external device having an output mode with a fixed output format and an output mode with a variable output format. An object is to enable switching to an output mode with a variable format.

In order to achieve the above object, a communication apparatus according to the present invention comprises the following arrangement. That is,
A communication device that can be connected via a communication interface to an external device having a first output mode for outputting in an output format corresponding to the data format of output target data and a second output mode for outputting only in a predetermined output format. And
First output means for outputting to the external device a mode setting command for setting the data output mode of the external device connected via the communication interface to either the first or second output mode;
Second output means for outputting an output instruction command for causing the external device to output data after outputting the mode setting command.

In addition, the control method of the present invention for achieving the above object is as follows.
This control method can be connected via a communication interface to an external device having a first output mode for outputting in an output format corresponding to the data format of output target data and a second output mode for outputting only in a predetermined output format. And
A first output step of outputting a mode setting command for setting a data output mode of the external device connected via the communication interface to the first or second output mode to the external device;
A second output step of outputting an output instruction command for causing the external device to output data after outputting the mode setting command.

  According to the present invention, it is possible to switch to the format variable mode before receiving data from an external device having an output mode with a fixed format and an output mode with a variable format. For this reason, for example, when a DVC set in the format fixed output mode is connected to a PC and data is transferred, the DVC output mode can be switched to the format variable mode under the control of the PC. Can be received.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

<First Embodiment>
FIG. 1 is a diagram illustrating a configuration example of a communication system according to the first embodiment. As described above, the DVC 101 is connected to the PC 103 via the IEEE 1394 cable 102. In the PC 103, an application 104 is running that takes in video data from the DVC 101 and edits it. As shown in FIG. 11, DV video data 1101 and 1103 and MPEG-2 video data 1102 are mixedly recorded on the magnetic tape 105. The application 104 can receive, edit, and edit video data in a plurality of formats that are synchronously transmitted while dynamically switching. For example, when DV format video data and MPEG-2 format video data are alternately transmitted as shown in FIG. 4B, these can be captured, played back, and edited. The application 104 is installed on the PC 103 and executed.

  FIG. 2 is a block configuration diagram showing an internal configuration of the DVC 101 which is an example of the communication apparatus according to the present embodiment. In the DVC 101 of the present embodiment, the imaging control unit 501 controls the digital camera unit 508 to capture a moving image and a still image of a subject. The digital camera unit 508 includes an image sensor such as a CCD or a CMOS sensor. The digital image captured from the digital camera unit 508 is converted into a target data format by the image processing unit 505 and recorded by the recording control unit 504 on the removable recording unit 509 (in this embodiment, the magnetic tape 105). Further, as described above, since the DVC 101 can record DV or MPEG-2 video data, the removable recording unit 509 records both types of video data as shown in FIG. Is possible. An interface for prompting the user to make a setting is displayed on the display unit 511 as to whether the DV system or the MPEG-2 system is used for recording. Thereby, the user can record video data by a desired method. The main control unit 502 controls the operation of the DVC 101. The IEEE 1394 interface 507 is a digital interface that conforms to the IEEE 1394 standard (see Non-Patent Documents 2 and 3). A DIF (digital interface) control unit 506 controls all input / output plugs included in the IEEE 1394 interface 507. The internal memory 510 stores a fixed mode management table managed by the DIF control unit 506. This fixed mode management table stores data indicating in which data format all input plugs and all output plugs of the IEEE 1394 interface 507 are fixed.

  FIG. 3 is a diagram illustrating an example of information exchanged by the IEEE 1394 interface 507 after the DVC 101 and the PC 103 are connected, and represents a communication process of the DVC 101 and a communication process of the PC 103 on which the application 104 is installed.

  When the IEEE 1394 connection between the DVC 101 and the PC 103 is established in 201, device information is acquired by a predetermined procedure (not shown) defined by the IEEE 1394 standard, and the PC 103 recognizes that the DVC 101 is connected. Then, the application 104 of the PC 103 issues an output mode control command 202 for releasing the fixed mode to the DVC 103. In the DVC 101, even if the output format is set to the fixed mode when connected, it can be switched to the variable mode. When the reproduction control command 203 is issued from the application 104 in the PC 103, the video data 204 to 206 reproduced from the DVC 101 are transmitted.

  In this example, the magnetic tape 105 shown in FIG. 11 is reproduced, and video data in the DV format, MPEG-2 format, and DV format are transmitted in order. FIG. 4 shows the relationship between the state recorded on the medium and the transmission data. The video data recorded as shown in FIG. 4A is output as shown in FIG.

  Next, the control command 204 for changing the output format of the DVC 101 to the variable mode will be described. FIG. 5 is a diagram showing a configuration of an OUTPUT PLUG SIGNAL MODE command, which is an example of a control command applicable to the present embodiment. This command is 8 bits wide and 3 bytes. As shown in Operand (1), 1 bit (seventh bit) is fixed / variable, and 2 to indicate formats such as MPEG-2 and DV. Bits (sixth and fifth bits) are allocated. Note that these two bits can be used to represent four different formats. Operand (0) can change the function by code.

  The seventh bit (Lock) represents an output mode, 0 represents a variable mode, and 1 represents a fixed mode. This variable mode means that the output format is not fixed as described above. Therefore, in the variable mode, the sixth and fifth bits (Mpeg / DV) indicating the output format have no meaning. The fixed mode is fixed to either DV or MPEG-2. Of course, it is possible to set a larger number of formats, and it is possible to specify a lock of a plurality of formats.

  For example, in order to output from the DVC 101 in the variable mode, an OUTPUTPLUG SIGNAL MODE control command of Operand (1) = 0x00 may be issued. When the Lock bit is set to “0”, the format bit has no meaning. Therefore, in the present embodiment, these two bits are set to “00”, but the same applies regardless of what numerical values “01”, “10”, and “11” are set.

  In the above-described embodiment, an example in which a command for setting the DVC 101 to a variable format is triggered by the establishment of connection by the IEEE 1394 interface 507 is described. However, the present invention is not limited to this. For example, the timing when the application 104 of the PC 103 is activated in a state where the connection by the IEEE 1394 interface 507 is established may be used as a trigger.

  As described above, according to the first embodiment, even if the image format output by the DVC 101 is fixed, the application 104 of the PC 103 changes the output mode of the DVC 101 to the variable mode and changes the output mode. The recorded contents of the format can be imported and used for editing.

<Second Embodiment>
In the first embodiment described above, a command for changing the output mode to the variable mode is issued by a predetermined trigger. That is, the case where the control command for switching to the variable mode is issued without confirming whether the DVC 101 is in the fixed mode or the variable mode before issuing the command has been described. In the second embodiment, before issuing a command for setting the output mode to the variable mode, the output mode set in the DVC 101 at that time is confirmed.

  Since the configuration of the communication system according to the second embodiment is the same as that of the first embodiment, description thereof is omitted.

  FIG. 6 is a diagram illustrating an example of information exchanged by the IEEE 1394 interface 507 after the DVC 101 and the PC 103 are connected in the second embodiment. Each vertical line represents the flow of time.

  When the IEEE 1394 connection between the DVC 101 and the PC 103 is established in 201, device information is acquired by a predetermined procedure (not shown) defined by the IEEE 1394 standard, and the PC 103 recognizes that the DVC 101 is connected. Then, the application 104 of the PC 103 issues an output mode confirmation command 211 for confirming whether the mode is the fixed mode or the variable mode toward the DVC 101. When it is confirmed by the response (output mode notification) 212 from the DVC 101 that the fixed mode is set, the output format needs to be changed variably (213), so the output mode for releasing the fixed mode. A control command 202 is issued. Then, a playback control command 203 is issued from the application. Hereinafter, it is the same as that of the first embodiment.

  If the DVC 101 is confirmed to be in the variable mode by the response 409b of the confirmation command 409a, the playback command 203 is issued immediately without issuing the output mode control command 202.

  FIG. 7 is a flowchart showing processing by the PC 103 up to the reproduction control according to the second embodiment. In step S601, the establishment of the IEEE 1394 connection or the activation process of the application 104 is detected as a trigger. In step S602, an output mode confirmation command (211) is issued. In step S603, it is determined whether the output mode is the fixed mode or the variable mode based on the returned response (output mode notification 212). If it is determined that the mode is the fixed mode, the process proceeds from step S603 to step S604, and an output mode control command is transmitted to switch the DVC 101 to the variable mode (202). In step S605, a playback control command is issued (203). In response to this command, the DVC 101 outputs video data (204 to 206). On the other hand, if it is determined that the output mode of the DVC 101 is the variable mode in the response command, the process skips from step S603 to step S605, and the reproduction command (203) is issued as it is.

<Third Embodiment>
In the third embodiment, stop control is performed on the DVC 101 prior to the operations of the first and second embodiments described above.

  FIG. 8 is a diagram illustrating an example of information exchanged by the IEEE 1394 interface 507 after the DVC 101 and the PC 103 are connected in the third embodiment. Although FIG. 8 shows the case where stop control is performed prior to the processing of the first embodiment, the configuration for performing stop control prior to the processing of the second embodiment is also apparent to those skilled in the art from the following description. I will.

  When the IEEE 1394 connection between the DVC 101 and the PC 103 is established in 201, device information is acquired by a predetermined procedure (not shown) defined by the IEEE 1394 standard, and the PC 103 recognizes that the DVC 101 is connected. The application 104 of the PC 103 first issues a stop control command to the DVC 101 (221), and then issues an output mode control command for setting the output mode to the variable mode (202). The subsequent procedure is the same as in the first embodiment. Similarly to the second embodiment, a confirmation command for confirming whether the mode is the fixed mode or the variable mode once may be issued, and the control command may be issued only when the mode is not the variable mode. Is as described above.

<Fourth embodiment>
In each of the embodiments described above, the DVC 101 has started processing (transmission of video data) as having been shifted to the variable mode by sending an output mode control command for changing the output mode to the variable mode. That is, transmission of video data is started without confirming the transition to the variable mode. However, there is a possibility that the control for changing to the variable mode may not succeed. For example, when the output format of the DVC 101 can be switched only by a mechanical switch or the like, the output format cannot be switched by a control command.

  Therefore, in the fourth embodiment, a configuration is provided in which it is confirmed whether or not the transition to the variable mode by the control command has succeeded, and if it has failed, the fact is notified. In the following, a case where confirmation processing is added to the processing procedure of the first embodiment will be described, but it will be apparent that the confirmation processing can also be added to the above-described procedures of the second and third embodiments.

  FIG. 9 is a diagram illustrating an example of information exchanged by the IEEE 1394 interface 507 after the DVC 101 and the PC 103 are connected in the fourth embodiment. After sending an output mode control command for requesting switching of the output mode (202), the PC 103 receives an output mode setting notification from the DVC 101 (231), thereby determining whether the output format has been successfully set. Check. If the output format has been successfully set, playback is instructed by a playback command (203).

  In the above description, the output format setting notification is received. However, the PC 103 that has issued the output mode control command may inquire about the output mode of the DVC 101 and confirm whether or not the mode has been switched to the variable mode. In this case, for example, it is possible to use the above-mentioned OUTPUT PLUG SIGNAL MODE as a status command. That is, an OUTPUTPLUG SIGNAL MODE status command in which 0xFF is assigned to all Operands is issued to the DVC 101, and the output mode is confirmed by the OUTPUT PLUG SIGNAL MODE command returned from the DVC 101.

  FIG. 10 is a flowchart for explaining processing according to the fourth embodiment. In step S901, establishment of IEEE 1394 connection or activation processing of the application 104 is detected as a trigger. In step S902, an OUTPUT PLUG SIGNAL MODE command is issued to change the output mode of the DVC 101 to the variable mode. Subsequently, the PC 103 confirms the output mode of the DVC 101 by issuing an OUTPUT PLUGSIGNAL MODE status command to the DVC 101 (step S903). As a result of this confirmation, if the transition to the variable mode is successful, the process proceeds to step S906, and a reproduction instruction is transmitted to the DVC 101 to start transmission of video data.

  On the other hand, if the transition to the variable mode has failed, the process proceeds to step S904, and this is notified to the user of the application 104 of the PC 103. In this example, a message such as “The output image format is fixed” is displayed on the display of the PC 103. In this embodiment, a button for inquiring whether or not to start transmission of video data is further provided on this screen. When the user gives an instruction to start transmission, the process proceeds to step S906 and a reproduction instruction is transmitted to the DVC 101. Thus, the user can easily cope with the transmission of the video data with the output format in the fixed mode, or the transmission of the video data after the output format of the DVC 101 is manually switched, for example.

  When the DVC 101 is configured to set the output mode with the changeover switch, in step S904, a display may be made to switch the output mode to the variable mode side. This is because the device information acquired when establishing the IEEE 1394 connection is stored for each model, holding the operation information indicating what type of switch the DVC 101 of the connection destination has and what switch should be operated. It can be realized by obtaining operation information corresponding to the model identified from the above and performing display based on the operation information.

<Fifth Embodiment>
By the way, the DVC 101 may be explicitly provided with an output image format fixed / variable changeover switch, but the output mode may be changed in one-to-one correspondence with switching of other functions. For example, the DVC 101 may include a switch for switching between a shooting / recording / playback mode in which shooting, recording, or playback is mainly performed and a PC connection mode in which the PC 103 is mainly connected to enjoy. In conjunction with this switching function, some output formats are fixed in the recording / playback mode, and some output formats are variable in the PC connection mode. In order to cope with such DVC 101, in step S904, the connected or activated application 104 may display a message for changing the DVC 101 to the PC connection mode to the user. At this time, a command for confirming whether the DVC 101 is in the PC connection mode or the shooting / recording / playback mode may be issued first, and the message may be displayed according to the response.

  When the IEEE 1394 connection is established, it is determined whether the output mode can be changed by a command from the acquired device information. If the output mode can be changed only by the changeover switch, Such a display as to guide switch switching may be performed.

  In each of the above embodiments, the case where the output mode is set to the variable mode has been described. However, the present invention can also be applied to the case where the output mode is set to a fixed mode with a desired output format.

It is a figure which shows the structural example of the communication system which concerns on 1st Embodiment. It is a block block diagram which shows the internal structure of DVC101 which concerns on 1st-6th embodiment. It is a figure which shows an example of the information exchanged by the IEEE1394 interface after connecting DVC101 and PC103. It is a figure explaining the relationship between the data on a tape, and the output data in variable mode. It is a figure which shows the structure of the OUTPUTPLUG SIGNAL MODE command which is an example of the control command applicable to 1st-5th embodiment. It is a figure which shows an example of the information exchanged by the IEEE1394 interface after connecting DVC101 and PC103 in 2nd Embodiment. It is a flowchart which shows the process by PC103 to the reproduction | regeneration control which concerns on 2nd Embodiment. It is a figure which shows an example of the information exchanged by the IEEE1394 interface after connecting DVC101 and PC103 in 3rd Embodiment. It is a figure which shows an example of the information exchanged by the IEEE1394 interface after connecting DVC101 and PC103 in 3rd Embodiment. It is a flowchart explaining the process which concerns on 4th Embodiment. It is a figure explaining the recording state of the video data on a tape. It is a figure which shows the relationship between the data on a tape, and the output data.

Claims (7)

A communication device that can be connected via a communication interface to an external device having a first output mode for outputting in an output format corresponding to the data format of output target data and a second output mode for outputting only in a predetermined output format. And
First output means for outputting to the external device a mode setting command for setting the data output mode of the external device connected via the communication interface to either the first or second output mode;
And a second output means for outputting an output instruction command for causing the external device to output data after outputting the mode setting command. Prior to the output of the mode setting command, the output mode of the external device is confirmed, further comprising a determination means for determining whether the output mode needs to be changed,
The output instruction command is output without causing the first output means to output the mode setting command when the determining means determines that the output mode change is unnecessary. Communication equipment.   The communication apparatus according to claim 1, further comprising a stop control unit that issues a stop command for stopping the operation of the external device prior to the output of the mode setting command by the first output unit.   The apparatus further comprises confirmation means for confirming whether or not the external device is set to an output mode requested by the mode setting command prior to the output of the output instruction command by the second output means. Item 4. The communication device according to Item 1.   The communication apparatus according to claim 4, further comprising display means for displaying that when the confirmation means confirms that the output mode setting has failed.   2. The communication according to claim 1, wherein the output of the mode setting command by the first output unit is triggered when a connection of the communication interface is established or when a predetermined application is started in the communication device. apparatus. Control of a communication device that can be connected to an external device having a first output mode for outputting in an output format corresponding to the data format of output target data and a second output mode for outputting only in a predetermined output format via a communication interface A method,
A first output step of outputting a mode setting command for setting a data output mode of the external device connected via the communication interface to the first or second output mode to the external device;
And a second output step of outputting an output instruction command for causing the external device to output data after outputting the mode setting command.

Images