Abstract:
An image capture apparatus includes an internal recording unit and a communication unit. The internal recording unit starts recording AV data including image and sound data on a recording medium in response to a record start instruction, and stops recording the AV data on the recording medium in response to a record stop instruction. If the image capture apparatus determines that an external storage device is connected to the communication unit, the image capture apparatus starts outputting the AV data to the external storage device in response to the record start instruction. If the image capture apparatus determines that the internal recording unit becomes unable to record the AV data on the recording medium and the communication unit is outputting the AV data, the image capture apparatus stops outputting the AV data to the external storage device in response to the record stop instruction.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an image pickup apparatus for outputting AV (Audio Video) data including image data and sound data to an external, and to its control method. 
   2. Related Background Art 
   Camera-integrated digital video recorders have been developed recently which have a digital interface (IEEE1394 interface) in conformity with the IEEE1394-1995 standards. 
   External storage devices have also been developed recently which can record AV data digitally output from an IEEE1394 interface of a camera-integrated digital video recorder. 
   If a user desires to record AV data recorded by a camera-integrated digital video recorder in an external storage device, the user interconnects the camera-integrated digital video recorder and external storage device, instructs the camera-integrated digital video recorder to start recording, and at the same time instructs the external storage device to start recording. 
   With this method, a user is required to instruct both the camera-integrated digital video recorder and external storage device to start recording. This operation is cumbersome and a user load is large. 
   SUMMARY OF THE INVENTION 
   The invention has been made in order to solve the above problem. It is an object of the invention to record AV data recorded by an image pickup apparatus in an external storage device without cumbersome operations. 
   According to a preferred embodiment of the invention, an image pickup apparatus comprises: recording means for recording AV data including image data and sound data; and communication means for starting an output of AV data to be recorded in the recording means in response to an instruction of a record start and for stopping an output of AV data to be recorded in the recording means in response to an instruction of a record stop. 
   Still other objects of the present invention, and the advantages thereof, will become fully apparent from the following detailed description of the embodiments. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a block diagram of a recording system according to an embodiment. 
       FIG. 2  is a flow chart illustrating the operation to be performed by an image pickup apparatus according to an embodiment. 
       FIGS. 3A ,  3 B,  3 C,  3 D and  3 E are diagrams illustrating AV data to be digitally output from the image pickup apparatus of the embodiment. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Preferred embodiments of the invention will be described with reference to the accompanying drawings. 
     FIG. 1  is a diagram showing a recording system according to an embodiment. Referring to  FIG. 1 , the recording system has a camera-integrated digital video recorder (hereinafter called an image pickup apparatus)  100  and an external storage device  120  for storing AV data digitally output from the image pickup apparatus  100 . 
   Next, with reference to  FIG. 1 , the main structure of the image pickup apparatus  100  of the embodiment will be described. Referring to  FIG. 1 , the image pickup apparatus  100  has an image pickup unit  101 , a microphone  102 , a recording/reproducing unit  103 , a storage medium  104 , a control unit  105 , a communication unit  106  and an operation unit  107 . 
   The image pickup apparatus  100  has a “camera mode” and a “VTR mode”. A user can select either the “camera mode” or the “VTR mode” by operating a mode select key of the operation unit  107 . 
   When the camera mode is selected, the control unit  105  activates the image pickup unit  101  and microphone  102  and makes the recording/reproducing unit  103  enter a record state or a record stop state. During this mode, the user can change the state of the recording/reproducing unit  103  either to the record state or the record stop state by operating a trigger key of the operation unit  107 . 
   When the VTR mode is selected, the control unit  105  stops the image pickup unit  101  and microphone  102  and activates the recording/reproducing unit  103 . During this mode, the user can reproduce AV data recorded in the storage medium  104 , temporarily stop, fast feed, or rewind by operating the operation unit  107 . 
   During the camera mode, the image pickup unit  101  picks up an optical image of a subject to generate image data. The image data generated by the image pickup unit  101  is supplied to the recording/reproducing unit  103 . During the camera mode, the microphone  102  collects external sounds to generate sound data. The sound data generated by the microphone  102  is supplied to the recording/reproducing unit  103 . 
   The recording/reproducing unit  103  generates AV data in conformity with a data format (e.g., the standard definition (SD) data format) defined by a home digital VCR scheme (hereinafter called a DV scheme) by HD Digital VCR Conference. This AV data includes the image data generated by the image pickup unit  101 , the sound data generated by the microphone  102  and associated additional data. 
   The AV data to be recorded in the storage medium  104  by the recording/reproducing unit  103  or the AV data reproduced from the storage medium  104  by the recording/reproducing unit  103  is supplied to the communication unit  106 . 
   The communication unit  106  has a digital interface in conformity with the IEEE1394-1995 standards or extended standards. If the external storage device  120  is connected to the communication unit  106 , the communication unit  106  digitally outputs AV data supplied from the recording/reproducing unit  103  in accordance with a predetermined communication protocol (e.g., a communication protocol in conformity with the IEC61883 standards). 
   With reference to  FIGS. 3A to 3E , a procedure to be executed by the image pickup apparatus  100  of the embodiment will be described, which procedure digitally outputs AV data in conformity with the SD format of the 525-60 scheme (NTSC scheme) in accordance with the communication protocol in conformity with the IEC61883standards. 
   First, the communication unit  106  generates ten DIF sequences from AV data for one frame supplied from the recording/reproducing unit  103 , as shown in  FIGS. 3A and 3B . As shown in  FIG. 3C , each DIF sequence is constituted of a header section, a sub-code section, a VAUX sections, and an audio &amp; video section. Image data and sound data are stored in the audio &amp; video section. 
   Next, the communication unit  106  generates one hundred and fifty DIF blocks from each DIF sequence, and an isochronous packet from six DIF blocks, as shown in  FIGS. 3D and 3E . Each isochronous packet is digitally output at every 125 μs in accordance with the isochronous transfer scheme defined by the IEEE1394-1995. 
   Next, the main structure of the external storage device  120  of the embodiment will be described with reference to  FIG. 1 . Referring to  FIG. 1 , the external storage device  120  has a communication unit  121 , a record unit  122 , a storage medium  123 , an operation unit  124  and a control unit  125 . 
   Similar to the communication unit  106 , the communication unit  121  has a digital interface in conformity with the IEEE1394-1995 standards or extended standards. The communication unit  121  digitally inputs AV data digitally output from the communication unit  106  of the image pickup apparatus  100  in accordance with a predetermined communication protocol (e.g. a communication protocol in conformity with the IEC61883 standards). The communication unit  121  receives the isochronous packet shown in  FIG. 3E  at every 125 μs to generate AV data shown in  FIG. 3A  and supply it to the recording unit  122 . 
   The recording unit  122  records AV data supplied from the communication unit  121  in the storage medium  123 . The data format of AV data to be recorded in the storage medium  123  by the external storage device  120  is the same as the data format of AV data to be recorded in the storage medium  104  by the image pickup apparatus  100 . In this embodiment, the storage medium  123  is a randomly accessible storage medium such as a magnetic disc, an optical disc, and a hard disk. 
   Next, with reference to  FIG. 2 , the main procedure to be executed by the image pickup apparatus  100  of the embodiment will be described. A portion of the procedure shown in  FIG. 2  is realized by a microcomputer of the control unit  105  which operates in accordance with a control program stored in a storage medium of the control unit  105 . 
   Step S 201 : The control unit  105  judges whether the current operation mode is the camera mode. If the operation mode is the camera mode, the flow advances to Step S 202 , whereas if not, the procedure is terminated. 
   Step S 202 : The control unit  105  judges whether the external storage device  120  is connected to the communication unit  106 . If connected to the external storage device  120 , the flow advances to Step S 203 , whereas if not, the procedure is terminated. 
   Step S 203 : The control unit  105  judges whether an instruction of a record start is input. The instruction of the record start is input to the control unit  105  if the trigger key of the operation unit  107  is operated. If this instruction of the record start is input, the flow advances to Step S 204 . 
   Step S 204 : The control unit  105  instructs the recording/reproducing unit  103  to start recording AV data, and at the same time instructs the communication unit  106  to start digitally outputting AV data. The recording/reproducing unit  103  records the AV data in the storage medium  104 , and at the same time supplies AV data recorded in the storage medium  104  to the communication unit  106 . The communication unit  106  digitally outputs the AV data supplied from the recording/reproducing unit  103  to the external storage device  120 . 
   Step S 205 : The control unit  105  judges whether the recording/reproducing unit  103  in operation has any trouble. If the recording/reproducing unit  103  cannot record AV data normally (e.g., if the capacity of the storage medium  104  becomes insufficient), the recording/reproducing unit  103  automatically stops the record of AV data and notifies the control unit  105  of the trouble. 
   Step S 206 : The control unit  105  makes the recording/reproducing unit  103  stop the record of AV data, although it makes the communication unit  106  continue to digitally output AV data. 
   Step S 207 : The control unit  105  judges whether an instruction of a record stop is input. The instruction of the record stop is input to the control unit if the trigger key of the operation unit  107  is operated. If the record stop instruction is input, the flow advances to Step S 208 . 
   Step S 208 : The control unit  105  makes the recording/reproducing unit  103  stop recording AV data, and at the same time makes the communication unit  106  stop digitally outputting AV data. 
   As described above, according to the recording system of this embodiment, digitally outputting AV data can be started or stopped only by operating the trigger key of the operation unit  107  of the image pickup apparatus  100 . Therefore, without any cumbersome operation, AV data recorded by the image pickup apparatus  100  can be recorded also in the external storage device  120 . Furthermore, since AV data recorded by the image pickup apparatus  100  can be recorded in the external storage device  120 , a dubbing time can be dispensed with and the edit work efficiency can be improved. 
   According to the recording system of the embodiment, even if the recording/reproducing unit  103  becomes unable to record AV data after the record start instruction is input (e.g., even if the capacity of the storage medium  104  becomes insufficient), it is possible to continue to digitally output AV data until the record stop instruction is input, so that AV data not recorded by the image pickup apparatus  100  can be reliably recorded in the external storage device  120 . 
   The invention may be embodied in other specific forms without departing from essential characteristics thereof. 
   For example, the data format of AV data of the embodiment is not limited only to the data format in conformity with the DV scheme, but it may be the data format in conformity with a transport stream scheme of MPEG2. 
   Therefore, the above-described embodiments are merely exemplary of this invention, and are not construed to limit the scope of the present invention. 
   The scope of the present invention is defined by the scope of the appended claims, and is not limited to only the specific descriptions in this specification. Furthermore, all the modifications and changes belonging to equivalents of the claims are considered to fall within the scope of the invention.