Patent ID: 6774824
Filing Date: 2004-08-10
Classification: H04N

Abstract:
A digital image encoding device comprising:conversion means for converting digital image data into a coefficient based on a spatial frequency; quantization means for quantizing the coefficient obtained by said conversion means; and coefficient bit modeling means for carrying out coefficient bit modeling by using said coefficient quantized by said quantization means, wherein said digital image data is divided into a plurality of subbands in said conversion means, wherein said coefficient bit modeling means comprises: code block division means for dividing each of said subbands into a plurality of code blocks; bit plane decomposition means for decomposing each of coefficients of said code blocks obtained by said code block division means into a plurality of bit planes for each bit weight; subbit plane decomposition means for decomposing each of said bit planes obtained by said bit plane decomposition means into a plurality of subbit planes based on usefulness; and predetermined data generation means for generating predetermined data in accordance with said subbit planes obtained by said subbit plane decomposition means, and requantization means for requantizing a predetermined subbit plane among said subbit planes obtained by said subbit plane decomposition means and passing data after said requantization to said predetermined data generation means.