Patent ID: 6950471

Claim:
A coding device for encoding image data, comprising: transforming means for performing discrete wavelet transformation on inputted image data, thereby generating transformation factors of a plurality of frequency sub-bands; coding means for entropy-coding each of said sub-bands and generating entropy-coded data for each of said sub-bands; and generating means for monitoring the amount of entropy-coded data of a predetermined sub-band in said each sub-band, and if the amount exceeds a predetermined code length, removing exceeded coded data from entropy-coded data of the predetermined sub-band, and if the amount does not reach said predetermined code length, adding dummy data to the coded data of the predetermined sub-band, thereby generating fixed length coded data of said predetermined code length, wherein said predetermined sub-band includes at least a lowest frequency sub-band, said generating means generates at least fixed length coded data for the lowest frequency sub-band.