Patent ID: 8351693
Filing Date: 2013-01-08
Classification: H04N

Abstract:
1. An image compression apparatus, comprising: a conversion unit configured to convert the color system of an input image data into the one composed of luminance components and color difference components; a division unit configured to divide the converted image data into a plurality of tiles; a wavelet transform unit configured to perform wavelet transform on each divided tile; a quantization unit configured to quantize each wavelet-transformed tile; a coding unit configured to code the quantized tiles by developing them into bit planes; a storage unit configured to store a plurality of different pattern data having the same data size as the bit planes; a determination unit configured to determine the bit planes having a small influence on image quality after decoding out of the developed bit planes; a selection unit configured to select the pattern data with a highest degree of coincidence with each determined bit plane by comparing the bit plane determined to have a small influence on image quality by the determination unit and the respective pattern data stored in the storage unit; and a replacement unit configured to replace each bit plane determined to have a small influence on image quality by the determination unit by the pattern data selected as the one with the highest degree of coincidence with the determined bit plane by the section unit.