IMAGE ENCODER, IMAGE DECODER, IMAGE ENCODING METHOD, IMAGE DECODING METHOD AND IMAGE ENCODING/DECODING SYSTEM

摘要

PURPOSE: An image encoder and an image decoder are disclosed which perform the image displacement other than parallel displacement on a relatively small scale and with which the processing time can be reduced and estimation with a high precision is enabled. CONSTITUTION: The constitution for compression-coding the input image comprises a movement compensating unit(9) which detects the frame-to-frame movement of the blocks into which the input image is divided. The constitution further comprises a movement detection unit(9) which includes a deformed block matching section which deforms only integer pixels, i.e. real sampling points present in a partial region corresponding to a reference image for movement detection into predetermined formats, cuts the deformed pixels out, and compares the cut-out deformed pixels with the integer pixels of the blocks of the input image and which outputs a moving vector which gives a minimum error extracted by the coordinate designation and a movement compensation unit which includes a corresponding point determination section which includes the deformed block matching section, correlates the blocks of the reference image in accordance with movement parameters obtained from comparison output, designates the coordinates, deforms and determines the block, and which outputs a predicted partial image. Further, an image decoder is so constructed as to correspond to the construction of the encoder. Moreover, the image decoder calculates the coordinates with a plurality of movement vectors by using also the coordinate values of the half-pixels of the reference image in a movement compensating unit and subjects the obtained pixel values to a deformation processing by using a deformation pattern in accordance with a deformed pattern.