Patent ID: 7224846

Claim:
An image coding apparatus comprising: a wavelet transform means for dividing an input image into subbands by wavelet transform; a code block generating means for dividing each of the subbands generated by the wavelet transform means into code blocks each of a predetermined size; a bit plane generating means for generating a bit plane including from a most significant bit to least significant bit in units of the code block; a coding pass processing means for processing each of sample points in the bit plane by any of a plurality of coding passes; and an arithmetic coding means for making arithmetic coding according to results of the coding pass processing; the coding pass processing means reading, from a storage means, significance/non-significance information indicating whether sample points in an area including the position of a sample point being currently processed and which is occupied by a predetermined number of samples, and those existing around the area, are significant or non-significant, and making a parallel comparison between the significance/non-significance information and a plurality of preset matching patterns, thereby detecting a next sample point to be processed.