Patent ID: 7983500

Claim:
An encoding method of losslessly encoding picture data composed of pixel data, the encoding method comprising the steps of: separating the pixel data whose number of quantizer bits is larger than eight bits into a first portion and a second portion, the first portion being composed of eight bits on an LSB side, the second portion being composed of remaining bits on an MSB side excluding the first portion; losslessly performing a first encoding process for the first portion; and losslessly performing a second encoding process for the second portion, the second encoding process being different from the first encoding process, wherein the second encoding process is performed by combining a first run-length process and a second run-length process, the first run-length process being performed by comparing a predetermined number of bytes composed of a plurality of second portions of adjacent pixels in the unit of the second portion, the second run-length process being performed by comparing the predetermined number of bytes composed of the plurality of second portions of the adjacent pixels in the unit of the predetermined number of bytes.