IMAGE ENCODING DEVICE, IMAGE ENCODING METHOD, AND IMAGE ENCODING PROGRAM, AND TRANSMISSION DEVICE, TRANSMISSION METHOD, AND TRANSMISSION PROGRAM

摘要

PROBLEM TO BE SOLVED: To resolve a problem in which it takes time for arithmetic encoding processing of switching a context depending on peripheral encoding information.SOLUTION: Provided is an image encoding device that divides a difference coefficient that is a conversion coefficient for a difference signal between an encoding target image and a prediction image into a plurality of subregions, and encodes the difference coefficient in subregion unit. A significant coefficient information encoding controller 706 and a calculation encoding part 701 encode significant difference coefficient information indicating that a difference coefficient value is not 0 and is significant, for each difference coefficient in an encoding target subregion. A difference coefficient value encoding controller 707 and the calculation encoding part 701 encode the difference coefficient value in a case where the significant difference coefficient information is significant, for each coefficient in the encoding target subregion. The significant coefficient information encoding controller 706 determines a context for encoding the significant difference coefficient information in the encoding target subregion on the basis of information that indicates significance of the difference coefficient in an encoded subregion adjacent to the encoding target subregion in horizontal and vertical directions.