Still video transceiver over the general telephone networks

A description is given of a still video transceiver that transmits full-colour still pictures to anywhere in the world over the general world-wide telephone networks. The system uses highly efficient picture coding that compresses picture data to about 3 bit/pixel with little degradation of quality. This accomplished by the combination of discrete cosine transform (DCT) and entropy coding. Highly reliable transmission under bad telephone-line conditions is realized by the combination of retransmission and fallback techniques. Experimental results of the data compression and transmission of a standard picture by the still video transceiver system are shown