IMAGE CONVERSION ENCODING DEVICE

摘要

PROBLEM TO BE SOLVED: To speed up convesion encoding processing time by shortening the processing time of a zigzag scanning part and reducing the quantity of output data from the zig-zag scanning part. SOLUTION: After executing discrete cosine transformation(DCT) by an orthogonal transformation part 1, a prescanning part 5 executes prescanning. A threshold processing part 6 compares a transformation coefficient (TC) with a threshold based on the prescanning result. When the TC is less than the threshold, the TC is set up to '0' and the position of an initial '0' when two '0's are continued is stored in a TC position memory part 7. At the time of zigzag scanning by the zigzag scanring part 2 after the prescanning, a scanning stop signal is outputted from the memory part 7 to the part of which TC is '0' to stop the scanning.