CODING DEVICE AND METHOD THEREOF

摘要

PURPOSE: To select a coding method offering an excellent coding efficiency based on a size of coding object data among plural coding methods by providing a 1st coding means and a 2nd coding means being specific means respectively to the device. CONSTITUTION: This coding device is provided with a 1st coding means used to code difference data when the size of difference data between a coding object picture element and pixel other than the coding object pixel in image information is smaller than a prescribed size and with a 2nd coding means different from the 1st coding means when the size of the difference data is larger than the prescribed size. The image data 100 inputted from the image memory 1 is inputted to a coding discrimination section 2 and a coding section 3. The coding mode decision section 2 selects the coding mode in which the code length is expected to be shorter when the image data 100 are DPCM-coded and generates the coded mode signal 101. The coding mode signal 101 switches a DPCM coding method.