ADAPTIVE VIDEO ENCODER FOR TWO-LAYER ENCODING OF VIDEO SIGNALS ON ATM (ASYNCHRONOUS TRANSFER MODE) NETWORKS

摘要

The quality of video images received at the remote end of an ATM networkcapable of transmitting data at high and low priorities is greatly improved at high cell losslevels by employing a two-layered video encoding technique that adapts the method forencoding information transmitted in the low-priority digital information stream to the rateof cell loss on the network so that compression efficiency and image quality are high whenthe network load is low and resiliency to cell loss is high when the network load is high.The encoder adapts its encoding method in response to a cell loss information signalgenerated by the remote decoder by selecting the prediction mode used to encode thelow-priority digital information stream, and by changing the frequency at which slice-startsynchronization codes are placed within the low-priority digital information stream(FIG. 1).