고압축 JPEG 영상을 위한 블록킹 현상 제거

초록

Nowadays JPEG encoder uses block based DCT and quantization to compress the size of still image. JPEG encoding method performs better compression efficiency than the other still image encoding method. However, when encoding a still image at low bit-rate, high frequency coefficients could be lost because of the coarse quantization so the blocking artifacts occur. In this paper, we propose the method of eliminating the blocking artifacts which occur when the still image is encoded by JPEG at a high compression rate. The principle of proposed algorithm is that the eliminating the blocking artifacts, which occur in the boundary of blocks, in DCT domain with 4x4 block-based method. First of all, observe the blocking artifacts with 4x4 block in DCT domain. Then eliminate the blocking effects using effective filtering method that is 4x4 block-based. Experimental results have clearly shown that our algorithm presents substantially higher quality in subjective and objective point of view than the other algorithms.

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