Patent ID: 8463061

Claim:
An encoding device, comprising: a wavelet transforming means for dividing a two-dimensional signal into subbands each of which is a plurality of frequency domains; a coefficient extracting means for extracting each component of each coefficient, which corresponds to an identical space coordinate, from an LH subband, an HL subband, and an HH subband belonging to an identical hierarchy, and constituting sets of the coefficients for each of space coordinates; a significant coefficient determining means for, for each of said sets of said coefficients, performing a process of determining whether or not one pre-designated component or more of one pre-designated subband or more is zero, thereby to generate one-bit determination information, respectively, and combining the determination information for each of said sets of said coefficients, thereby to generate flag information having a plural-bit length; a flag information encoding means for subjecting said flag information to variable-length encoding for each of said sets of said coefficients; and a significant coefficient encoding means for, for each of said sets of said coefficients, subjecting the component of which a value is not zero to the variable-length encoding with respect to the components of the coefficients for which said determining process has been performed, and when the components of the coefficients for which said determining process has not been performed exist, subjecting them to the variable-length encoding irrespective of zero/non-zero.