IMAGE CODING METHOD AND DEVICE THEREFOR

摘要

PROBLEM TO BE SOLVED: To reduce an arithmetic operation amount and the processing time in the image coder that decides a quantization step based on given binding conditions and generated information quantity through the 2-path type coding control. SOLUTION: The device is provided with a small block division section 12 dividing a frame of a received image into small blocks, a characteristic quantity measurement section 13 measuring a characteristic amount fsk (k is a type of a characteristic amount: 1<=k<=K) for each small block, an in-frame statistic quantity calculation section 15 calculating a statistic quantity fcsk of the characteristic quantity for each frame, and a generated information amount estimate section 17 calculating an estimate value Ge of the generated information quantity when a concerned frame is coded by a tentative quantization step Qp decided in advance and executes the generated information multi- value processing estimate processing. In the actual coding processing, the quantization step Q1 used for actual coding to each frame is decided so as to be in matching with the binding conditions based on the estimate value Ge of the generated information quantity.