IMAGE DECODING DEVICE, IMAGE DECODING METHOD, IMAGE DECODING PROGRAM, RECEIVING DEVICE, RECEIVING METHOD, AND RECEIVING PROGRAM

摘要

PROBLEM TO BE SOLVED: To realize an efficient arithmetic encoding processing for converting context by peripheral decoding information.SOLUTION: Provided is an image decoding device that divides a differential coefficient, the differential coefficient being the conversion coefficient of a differential signal for an image to be decoded and a predicted image, into a plurality of partial regions and decodes the differential coefficient in partial region units. For each differential coefficient within a partial region to be decoded, a significant coefficient information decoding control unit 1006 and an arithmetic decoding unit 1001 decode significant differential coefficient information indicating that the differential coefficient has a differential coefficient value that is not 0, and that the differential coefficient value is significant. A differential coefficient value decoding control unit 1007 and the arithmetic decoding unit 1001 decode the differential coefficient values for each pixel within a partial region to be decoded when the significant differential coefficient information is significant. The significant coefficient information decoding control unit 1006 determines a context for decoding the significant differential coefficient information within a partial region to be decoded on the basis of information indicating the significance of the differential coefficients within the partial regions that have been decoded.