QUANTIZATION CONTROLLER, QUANTIZATION CONTROL METHOD AND CODER

摘要

PURPOSE:To reproduce an image pattern with higher image quality by setting optimizingly quantization scale while taking the image quality into account when data are encoded by the MPEG method or the like. CONSTITUTION:The controller is provided with a noise detection circuit 15 detecting noise generated in the process of quantization by DC transformation 1. The quantization scale of a quantizer 2 is controlled based on the noise detected by the noise detection circuit 15 via a quantization control circuit 8. Since the noise generated attended with quantization is estimated by the noise detection circuit 15, the quantization scale is set based on the S/N together with an output code quantity and a reproduced pattern is made stable with high quality when a same coding rate is used.