To divide a high-resolution image and display the respective divided images simultaneously on a display device.

A scanning part scans each of a plurality of lines according to a predetermined order in an image comprising the plurality of lines. A reference line memory holds a reference line to be referred in encoding the plurality of lines. An encoding part encodes the line scanned while referring the reference line in the case that the line other than in-region head lines that are head lines in the plurality of respective regions generated by division of the image along the line is scanned. A decoding part, every time when the line is encoded, decodes the encoded line to update the reference line in the reference line memory with the decoded line. An encoded image output part outputs the scanned line and the line encoded by the encoding part as an encoded image.