Abstract: On the base of studying the series of ITU-T image encoding standard and the transfer capability of the ISDN multimedia telecommunication, we choose the special image encodingchips to implement the ISDN multimedia videophone terminal which is complied with ITU-T
H.320 standard.Because we use the postprocessing and preprocessing.The subject quality of the image is overwell.

Key words: image coding, multimedia videophone, PIC bus