Hierarchical dependency context model based arithmetic coding for DCT video compression
This paper presents an arithmetic coding scheme for DCT coefficients in video compression, in which the number of non-zero coefficients, significant map and level information for a DCT block are used as coding elements. To exploit the statistical correlations, an hierarchical dependency context model (HDCM) is proposed, where the number of non-zero coefficients and scanned position are used to capture the magnitude varying tendency of DCT coefficients. Then a new binary arithmetic coding using HDCM (HDCMBAC) is proposed to code the coding elements. Experimental results demonstrate that HDCMBAC can achieve the similar coding performance as CABAC at low and high QPs. Meanwhile the context modeling and arithmetic decoding in HDCMBAC can be carried out in parallel, since the context dependency only exists among different parts of basic coding elements in HDCM.