Patent ID: 8363719

Claim:
An encoding apparatus which divides an input image into a plurality of blocks and encodes the image, comprising: a detection unit configured to determine a characteristic of the image of each of the plurality of blocks and to detect a block in which visual degradation is noticeable, wherein the block to be detected includes at least one of a flat block, an edge block and a skin color block; a determination unit configured to determine a quantization parameter of each block based on a detection result of the detection unit; a transformation unit configured to perform orthogonal transformation of each block and quantization using the determined quantization parameter; an encoding unit configured to perform variable-length encoding of a transformation result of the transformation unit; an inverse transformation unit configured to inversely transform the transformation result of the transformation unit to generate a locally decoded image; and a calculation unit configured to calculate a reference value and change a criterion to determine the characteristic of the image according to the reference value, wherein the detection unit detects the block in which the visual degradation is noticeable, in accordance with the criterion changed by the calculation unit.