Orthonormal wavelet-based contourlet transform coding using an EBCOT-like algorithm
In this paper, an image coding algorithm based on a rate-distortion optimized wavelet-based contourlet transform (WBCT) decomposition and on a block-partitioning coding scheme which quantizes each subband separately is proposed. In this way, our algorithm naturally overcomes the difficulty in defining parent-child relationships for wavelet-based contourlet subbands, which exists in the zerotree based methods. The main merit of the proposed method is that the Wavelet-Based Contourlet Transform (WBCT) can provide optimally sparse representation of objects with singularities along c2 edges. The experimental simulation results show that the proposed algorithm significantly outperforms SPIHT and JPEG2000 schemes and also surpasses recent WBCT based image coding algorithms, in terms of both the PSNR-rate curves and visual quality.