Device for encoding digital video signals including means for

Abstract

Device for encoding digital video signals which are representative of the luminance or the chrominance of a given number of pixels of a picture divided into blocks, including respective circuits for correlation reduction, normalization, quantization, encoding, and rate control, the latter receiving the output signals from the encoding circuit in accordance with a variable rate and supplying rate control signals applied to the normalization circuit and encoded signals at a constant rate at the output of the encoding device. In this device, the normalization circuit firstly includes circuits for non-linear treatment (31, 32, 33, 34, 35, 36, 37a, 37b) for receiving the blocks and the rate control signals as well as the classification indications of the blocks into distinct families in accordance with the values of different parameters determined from these blocks by a classification circuit (20) and subsequently for effecting respective distinct non-linear treatments on these blocks and these rate control signals in conformity with the families. The normalization circuit also includes normalization circuit (38, 39) for determining the normalized signals from various signals thus treated.