Abstract: A coding device has a difference calculating unit that calculates a quantized value, which is represented by lower-order bits than a quantization bit rate allocated to a processing unit in image data in a selected coding pattern, from a quantized value obtained by quantizing a pixel value in the processing unit with a maximum quantization bit rate in the coding device, as a difference.

Abstract: An IC card unit has a memory, various types of image processing sections, and an IC card interface and, when fitted to an external information processing device, it is contained therein. An image input unit, which has an image forming part and an image pick-up part and which is protruded outward of the information processing device, captures an image of a subject. The image processing sections execute image processing on image data written into the memory, and converts the data into image data optimum for display by an image display of the information processing device. The IC card interface transmits image data that has undergone the image processing to the information processing device side, enabling real-time monitoring. Access from the information processing device side is enabled so that image processing conditions and the like can be set.