MOVING IMAGE DECODING METHOD AND MOVING IMAGE DECODER

摘要

PROBLEM TO BE SOLVED: To attain high speed decoding process and to reduce an occupancy rate of a memory data bus. SOLUTION: A predicted error from an inverse discrete cosine transformation(IDCT) 4 is supplied to a detection circuit 21 that detects a level below a threshold level, in which it is determined whether or not the predicted error is below a prescribed threshold level T. In the case that the predicted error is higher than the threshold level T, a reference image from a reference memory 8 is fed to a half pel arithmetic circuit 12, where interpolation processing is conducted and the result is added to the predicted error at an adder 5 and decoded image data are obtained. The decoded image data are outputted via a selector 23. In the case that the predicted error is equal to the threshold level T or below, the addition processing is skipped and the selector 23 selects an output of the half pel arithmetic circuit 12 and provides an output of the selected output. Thus, the addition processing is omitted and the decoding processing is accelerated.