Adaptive Quantisierung eines Pufferspeichers/Quantisierers für Transformationscodierer für Video

摘要

A buffer/quantizer controller (110) in a video coder (100) utilizes the average quantization step size employed for the previous frame, the average number of bits produced per pel by the video coder for the image contained in the previous frame and the current frame buffer (108) fullness level to obtain an indication of image complexity. A target current frame quantization step size to be employed by the video coder in encoding a current frame is based on the indication of image complexity. Optionally, the target frame quantization step size is adjusted by a mapping procedure, at predetermined intervals within each frame period, to account for the current buffer fullness. The map employed by the mapping procedure is adjusted in accordance with the target frame quantization step size. <IMAGE>