An electronic camera includes a CCD imager. When a motion image recording mode is selected, the depression of a shutter button creates a plurality of screens of image signals based on camera signals outputted from the CCD imager. A system controller calculates an optimal compression ratio for compressing the image signal to a target size and sets optimal compression ratio to an image compression circuit. The image compression circuit compresses a current image signal obtained following a preceding image signal with this optimal compression ratio. Such compression process creates a plurality of screens of a compressed image signals, whereby a write control circuit records the plurality of screens of the compressed image signals to a memory card.