Patent ID: 7333661

Claim:
An image coding device for dividing an input signal into tiles of a certain size, for transforming an image signal included in each tile to a frequency component and obtaining a transformation coefficient, for quantizing an obtained transformation coefficient to a quantized coefficient, for entropy coding the quantized coefficient, for calculating a quantized distortion upon quantizing of the transformation coefficient, and for controlling a code amount of a coded data obtained by the entropy coding using the quantized distortion, comprising: a tile classifying unit for classifying each tile based on its characteristic into a plurality of categories by referring to the transformation coefficient, and for outputting a classified result; a weighting unit for weighting the quantized distortion based on an output of the tile classifying unit; and a rate controlling unit for controlling the code amount of a code data obtained by the entropy coding, based on the quantized distortion weighted by the weighting unit.