Even when a remaining amount of an image memory built in a digital camera is decreased, the photographing can be further continued while reserving a photographed image. An image which is obtained from an image input unit including image pickup means is accumulated into an image memory. When a remaining amount calculating unit detects that the remaining amount of the image memory is small, an image record discriminating unit compares it with an image size in a photograph mode at that time which is obtained from an image size table, thereby discriminating whether the continuation of the photographing can be performed or not. When the photographing is impossible, an image selecting unit selects an old image, an image in which the number of colors is small, or the like on the basis of management data regarding the photographed images in a memory managing table. The selected image is transmitted by a PHS communication by a data transmitting apparatus. After it was transmitted, the image is erased from the image memory.