Kodierung von analogen Bildsignalen

摘要

An apparatus for coding an input analog video signal into a digital code comprises an A/D converter (2) for converting the input analog video signal (Sv) to a first quantization code having a first number of bits, a class sorting circuit (5), supplied with the first quantization code from the A/D converter (2), for effecting a class sorting process on a plurality of pixels including a pixel to be marked, based on the first quantization code corresponding to the pixel and the first quantization code corresponding to each of the pixels provided near the periphery of the pixel, and a quantizing circuit (4), supplied with the first quantization code produced from the A/D converter (2) and the result of class sorting by the class sorting means (5), for adaptively converting the first quantization code into a second quantization code having a second number of bits smaller than the first number of bits, based on the result of class sorting by the class sorting circuit (5). <IMAGE>