Patent ID: 6058217
Filing Date: 2000-05-02
Classification: G06T

Abstract:
An image coding apparatus for coding an image of a component signal constituted by a plurality of components, comprising:block making means for subdividing said image to make a predetermined number of image blocks;maximum/minimum value detecting means for detecting a maximum value and a minimum value of each of said plural components which constitute the component signals in pixels within said blocks;dynamic range calculating means for calculating a dynamic range equal to a difference value between the maximum value and the minimum value of each of said plural components;block dynamic range detecting means for detecting a block dynamic range equal to a maximum value thereof from said dynamic range of each of the respective plural components;quantizing step width determining means for determining a quantizing step width used to quantize each of said plural components based upon said block dynamic range; andquantizing means for quantizing each of said plural components in accordance with said quantizing step width determined by said quantizing step width determining means.