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ABSTRACT: This paper proposes novel scalable mesh coding designs exploiting the intraband or composite statistical dependencies between the wavelet coefficients. A Laplacian mixture model is proposed to approximate the distribution of the wavelet coefficients. This model proves to be more accurate when compared to commonly employed single Laplacian or generalized Gaussian distribution models. Using the mixture model, we determine theoretically the optimal embedded quantizers to be used in scalable wavelet-based coding of semiregular meshes. In this sense, it is shown that the commonly employed successive approximation quantization is an acceptable, but in general, not an optimal solution. Novel scalable intraband and composite mesh coding systems are proposed, following an information-theoretic analysis of the statistical dependencies between the coefficients. The wavelet subbands are independently encoded using octree-based coding techniques. Furthermore, context-based entropy coding employing either intraband or composite models is applied. The proposed codecs provide both resolution and quality scalability. This lies in contrast to the state-of-the-art interband zerotree-based semiregular mesh coding technique, which supports only quality scalability. Additionally, the experimental results show that, on average, the proposed codecs outperform the interband state-of-the-art for both normal and nonnormal meshes. Finally, compared with a zerotree coding system, the proposed coding schemes are better suited for software/hardware parallelism, due to the independent processing of wavelet subbands.
IEEE Transactions on Multimedia 01/2011; · 1.93 Impact Factor
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ABSTRACT: In this paper, a novel wavelet-based composite mesh coding scheme is presented. In contrast to the state-of-the-art scalable interband mesh codec, the proposed codec relies on composite dependency models that capture both the interband and intraband statistical dependencies between wavelet coefficients. Additionally, each wavelet subband is processed independently, which allows for parallelized processing and for a progressive reconstruction of each mesh resolution level. Compared to the state-of-the-art, the proposed codec yields for almost all rate points superior compression performance in L<sub>2</sub> -sense. Furthermore, the generated bitstreams are near-optimal in rate-distortion sense, which eliminates the need of a post-compression rate-distortion optimization technique.
Image Processing (ICIP), 2009 16th IEEE International Conference on; 12/2009
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ABSTRACT: In this paper, a scalable intraband wavelet coding technique for semi-regular topology surface meshes is proposed. The choice of an intraband codec design is justified through an information theoretic analysis of the statistical dependencies between the wavelet coefficients resulting from a wavelet-based decomposition of the input 3D mesh. The bitstream produced by the proposed codec is both resolution and quality scalable. This lies in contrast with well-known zero-tree based interband coding techniques that only support quality scalability. The experimental results show that, on average, the proposed codec outperforms the state-of-the-art zero-tree based interband codec in rate-distortion sense when using the L<sub>2</sub> norm as target distortion metric.
Digital Signal Processing, 2009 16th International Conference on; 08/2009
