Method and system for encoding and decoding video data.

摘要

An original image signal is encoded (1) into an image code signal of a predetermined format through an approximation process on colors. A first luminance component is derived (11) from the image code signal. A second luminance component is derived (12) from the original image signal. A difference between the first luminance component and the second luminance component is derived (13). The difference is converted (10) into a luminance corrective signal. The image code signal and the luminance corrective signal are transmitted via a common transmission line. In a decoder (6), the luminance corrective signal is decoded (14) to a luminance difference signal, which is added (17) to an image signal decoded (8,9) from the image code signal.