PICTURE CODING DEVICE AND PICTURE PROCESSING SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a picture coding device that attains suppression of picture quality deterioration. SOLUTION: A degree of picture complexity detection means 11 detects the degree of picture complexity of one frame picture. A quantization scale calculation means 12 calculates a quantization scale Q from the amount of information for one frame picture. A rate calculation means 13 uses a normalized activity N- act calculated from the degree of picture complexity or the normalized activity N- act and a motion vector V and calculates a rate Ra of a block where the quantization scale within one frame becomes large. An adaptive quantization execution decision means 14 compares a threshold R1 and the rate Ra, executes adaptive quantization when the rate Ra is bigger than the threshold R1 and decides not to perform the adaptive quantization when the rate Ra is smaller than the threshold R1. An adaptive quantization scale calculation means 15 calculates an adaptive quantization scale Qa from the quantization scale Q on the basis of the normalized activity N- act and the rate Ra at the time of the adaptive quantization.