APPARATUS AND METHOD FOR ENCODING IMAGES, AND APPARATUS AND METHOD FOR DECODING IMAGES

摘要

Disclosed are an apparatus and method for encoding images, and an apparatus and method for decoding images. The image-encoding apparatus according to one embodiment of the present invention comprises: a target block dividing unit which divides a target block of an input image to be encoded into a plurality of sub-blocks in accordance with the positions of pixels; a key block encoding unit which selects a random key block, the size of which is larger than that of at least one pixel, from among the plurality of sub-blocks divided by the target block dividing unit, and performs intra-prediction or inter-prediction on the selected key block; and a non-key block encoding unit which designates the rest of the divided sub-blocks, except for the selected key block, as a non-key block, and performs intra-prediction on the designated non-key block using values of peripheral pixels of the key block decoded on the basis of the key block encoding unit, and values of peripheral pixels of the current block. According to the present invention, spatial redundancy in a block can be efficiently removed, even when the size of a basic block for encoding increases in a high-resolution image-encoding process.