Method for image variable length coding and device for carrying such method.

摘要

Such a method includes a quantisation step (20) followed by a variable-length coding step (30), following which the signals obtained are recorded in a buffer memory (40). The quantisation pitch used is calculated on the basis of a downstream parameter which is a decreasing function of the rate of occupancy of the buffer memory, and of an upstream parameter which is a function of the quantity of information contained in the image. According to the invention, the said upstream parameter comprises at least one multiplicative factor which is a decreasing function of the saturation of one of the two U or V chrominance components over the current block or macroblock with respect to the rest of the image. Application to transmission and to storage of images.