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In this paper, we introduce a novel way to represent an image sequence, which naturally exhibits the temporal persistence of the textures. Standardized representations have been thoroughly optimized, and getting significant improvements has become more and more difficult. As an alternative, Analysis-Synthesis (AS) coders have focused on the use of texture within a video coder. We introduce here a new AS representation of image sequences that remains close to the classic block-based representation. By tracking textures throughout the sequence, we propose to reconstruct it from a set of moving textures which we call motion tubes. A new motion model is then proposed, which allows for motion field continuities and discontinuities, by hybridizing Block Matching and a low-computational mesh-based representation. Finally, we propose a bi-predictional framework for motion tubes management.

This article introduces a novel approach for scalable video coding based on an analysis-synthesis scheme. Active meshes are used to represent motion model, this permits to exploit temporal redundancy along motion trajectories in a video sequence using temporal wavelet transform. The use of 3D wavelets in the coding strategy provides natural scalability functionalities to the video coder. Furthermore, the analysis-synthesis scheme allows to decouple motion and texture and to code these informations separately. Motion can then be lossy coded, bitrates gain can be reported to texture coding. Because motion is lossy coded, a new quality criterion measured in the texture domain is then proposed. Finally, the proposed analysis-synthesis video coding scheme overcomes some of the limitations of existing video coding schemes using 3D wavelets, limitations due for the most part to the use of block-based motion model. Our video coding scheme performs as well as fully optimized H26Lv8, while providing a scalable bitstream.

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