Techniques for Reducing the Visibility of Transmission Errors in Digitally Encoded Video Signals

Abstract

This paper is concerned with the problem of transmission errors in digitally encoded television signals. Various techniques for reducing the visibility of transmission error effects in the reconstructed signals have been evaluated using computer-produced film sequences. It is found that the visibility of errors in element difference coders is sharply reduced if an erroneous line is replaced by an average of adjacent lines. It is shown that the visibility of errors in two coders that use spatial prediction is low and can be further reduced by using a "leaky" predictor. The implications of these results for in-frame, interframe, and facsimile encoders are discussed.