Coding directional angles using context-based adaptive arithmetic code

When the quadtree-based segmentation technique is used for adaptive directional lifting-based (ADL) wavelet transform, the direction information usually consists of a segmentation quadtree map and prediction error of the directional angles. In an adaptive directional lifting-based wavelet transform, the prediction error is coded by the arithmetic coding. In this paper we modify the ADL scheme and propose a new directional angle coding scheme which uses the CABAC algorithm to code the prediction error by taking the direction information into account. Experimental results show that performance of the ADL is improved up to 0.13 dB.