In this paper, we propose an efficient and embedded3-d wavelet video coding algorithm, which exploits inter- and intra-subband correlations along spatial and temporal directions through the use of spatio-temporal ori...
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ISBN:
(纸本)9781424424085
In this paper, we propose an efficient and embedded3-d wavelet video coding algorithm, which exploits inter- and intra-subband correlations along spatial and temporal directions through the use of spatio-temporal orientation trees. The spatio-temporal treestructure has nodes as a block of n x n coefficients as a basic unit in contrast to a single coefficient in the 3-d SPIHT. The proposed algorithm combines the benefits of both 3-d zerotree and zeroblock based coding approaches in a single algorithm. This not only helps in exploitation of both inter- and intra-subband correlations efficiently but also results in better aggregation of zerotrees. Simulation results show the improved performance of the proposed coder over a 3-d SPIHT coder for the test sequences considered. Like 3-d SPIHT, the proposed algorithm posses all its functionatities such as fully embedded bit stream, precise rate control and multi-resolution scalability.
A method is developed to generate the 3-d binary representation for a tree-like object from three mutually orthogonal projections. This is done by first backprojecting the binarized images from three directions and th...
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A method is developed to generate the 3-d binary representation for a tree-like object from three mutually orthogonal projections. This is done by first backprojecting the binarized images from three directions and then iteratively removing artifacts in the backprojection. Three different algorithms have been developed: the Lagrange multiplier algorithm (LMA), the conjugate gradient algorithm (CGA), and the minimum-voxel representation algorithm (MRA). The performance of these algorithms under noise-free conditions is evaluated using mathematically projected images of a 3-d tree structure. While all three algorithms are capable of producing a relatively accurate reconstruction, the MRA is superior not only because it requires the least amount of computation but also because it uses binary instead of gray-scale information in the input images. Reconstruction of 3-d coronary arterial structures using MRA is further verified with x-ray images of a human chest phantom and shows a satisfactory performance. The result of this study should be valuable for 3-d imaging of blood vessels.
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