An image synthesis unit receives respective pixel values for a single horizontal row of a ¼ demosaiced image, a 1/16 demosaiced image, and a 1/64 demosaiced image from a pyramid filter for reducing, in a plurality of stages, a frame of a moving image that is captured. The image synthesis unit then connects the pixel values in a predetermined rule so as to generate a virtual synthesized image and outputs the synthesized image in the form of streams. A control unit of an image transmission unit notifies a data selection unit of a request from a host terminal. The data selection unit selects and extracts necessary data from respective streams of pieces of data of the synthesized image, a RAW image, and a 1/1 demosaiced image, and generates a stream of data to be transmitted. A packetizing unit packetizes the stream and transmits the packetized stream to the host terminal.