Image data acquired by using a camera mounted on a mobile telephone can be transmitted to a connected PC. However, if the telephone is called and communication is started, imaging cannot be performed and this cannot be grasped by the PC. A storage unit (101) contains second image data indicating that communication with the first image data indicating that call is performed is in progress. The image acquired by a camera (102) is compressed/encoded by a JPEG compression unit (103) and stored in frame unit in an image data storage unit (104). A control unit (112) reads out image data so as to be a predetermined transmission rate and transmits it to a host PC (120) via an I/F (113). When the call is reported from a base band signal processing unit (108), the control unit (112) causes the camera unit (102) to interrupt imaging, reads out the first image data from the storage unit (101) and transmits it to the host PC (120). When a communication start is reported from an operation unit (105), the second image data is read out from the storage unit (101) and transmitted to the host PC (120) in the same way. |