IMAGE DECODER

摘要

PROBLEM TO BE SOLVED: To surely detect a block in which an error is generated in a decoding process. SOLUTION: A horizontal differential component calculation unit 21 obtains change value between pixel levels of adjacent pixels straddling over a boundary of horizontally adjacent decoded blocks and change value between pixel levels in the respective horizontally adjacent decoded blocks. A horizontal continuity decision unit 23 decides the continuity of the horizontally adjacent blocks. A vertical differential component calculation unit 22 and a vertical continuity decision unit 25 are made to operate in the same way. A block continuity decision unit 25 decides the continuity between the adjacent blocks according to the decision results of the horizontal continuity decision unit 23 and the vertical continuity decision unit 24.