Image compression and decompression based on a flat pixel group level, group pixel coorindinate positions, and the number of pixels for the group

摘要

An encoding apparatus whereby image signals provided in units of frames, each having a plurality of pixels, are divided into macro groups, and the pixels in each macro group are combined, forming a group. The pixels of the group are encoded on the basis of the level data representing the signal level of the representative pixel in the group, the position data concerning all pixels of the group and the data representing the number of the pixels existing in the group.