Color characteristic quantity processor, and color characteristic quantity processing method

A color characteristic quantity processor capable of reducing the volume of processing at the time of computation of a color descriptor and miniaturizing the processor by minimizing image memory for storing decoded data. A VLD section 12 outputs only DC component data among decoded data, and the data are inversely-quantized by an IQ section 14. In the case of an intra frame coded image, an output from the IQ section 13 is stored in image memory 16 without modification. In the case of an inter frame coded image, data which have been subjected to motion compensation performed by an MC section 18 and an addition section 20 are stored. A frame division section 22 divides the data stored in the image memory 16 into 64 (8x8) areas. In each of the areas, a mean value of the data is computed. An 8x8 DCT section 24 subjects the 64 mean values to DCT, and a predetermined number of DCT coefficients from the top are stored as color descriptors in a color characteristic quantity data holding section 28.