Data transmission apparatus, method and program, data reception apparatus and method, and data transmission and reception system, using differential data

摘要

A data transmission apparatus and the like are provided which, in sending data of a large capacity such as still image data, can significantly reduce an amount of transmission data while suppressing deterioration of the data. The transmission apparatus of the present invention include: a differential data calculation section for, assuming that data to be a reference is reference data and data to be compared with the reference data is object data, comparing the reference data and the object data to calculate a difference between both the data as differential data; a differential data amount reduction section for reducing a transmission data amount of the differential data obtained by the differential data calculation section such that the differential data can be restored; and a data transmission section for sending the differential data with its data amount reduced by the differential data amount reduction section.