To provide an image code converting system with which the system configuration for providing a small picture compressed signal corresponding to the moving image of a small picture while keeping picture quality high can be simplified by avoiding the repetition of decoding/encoding processing to the image signal of a compression-encoded big picture.

Concerning the moving images of plural small pictures provided from cameras 1a, 1b..., an MUX(multiplexer) 2 composites a big picture image by arranging frames at the same time, an ENC(encoder) 3 compression-encodes this big picture image for the unit of a small picture and outputs the result and a CON 4 directly demultiplexes/converts the compressed signal of this big picture on the other hand so that plural small picture compressed signals respectively corresponding to plural small pictures can be provided. When using motion compensation, the ENC 3 forcedly sets a motion vector, which is generated in the case of referring to the small picture, to '0'. Besides, when compositing the plural small pictures, the MUX 2 forms the boundary area of higher contrast in comparison with that of a picture at the boundary part of small pictures.