Differential Encoding of Composite Color Television Signals Using Chrominance-Corrected Prediction

Abstract

A digital coding technique which interfaces efficiently with composite color signals is clearly desirable for connections formed from a chain of analog and digital transmission links. This paper reviews a number of such techniques, and develops a predictive encoding algorithm, termed chrominance-corrected prediction, which is efficiently matched to the nature of the composite signal, and which avoids the need for prior separation of the signal into luminance and chrominance components. The application of composite predictions to PAL and NTSC signals is discussed, and experimental results are described which indicate that a saving in excess of 2 bits/sample can be achieved over PCM for similar picture quality.