A videophone codec for ISDN application

A low-bit-rate image codec for videophone and B/2B-ISDN (integrated services digital network) applications is presented. The encoder skips two frames over three images and encodes one image over three, using DCT (discrete cosine transform)-Huffman coding, and sends this information together with the motion vectors computed on overlapped blocks. At the receiver the missing frames are reconstructed by linear interpolation using coded frames and corresponding motion vectors. The resulting video sequences indicate that for a videophone in ISDN network applications, an acceptable quality image is obtained