The block-matching algorithm is the most popular motion compensation technique in video coding. However, it cannot provide acceptable quality at very low bit rate. In this paper, a new mesh-based motion compensation method is proposed to attack the problem. First, a regular non-uniform mesh, which has regular structure with variable patch size, is presented. The patch size is varied according t...

Methods for object-based compression and composition of natural and synthetic video content are currently emerging in standards such as MPEG-4 and VRML. This paper describes novel techniques for compression of 2-D triangular mesh geometry and motion, enabling efficient representation and manipulation of video content. Specifically, mesh geometry is compressed by predictive coding of mesh node l...

This paper presents a method for video sequence coding, using motion estimation over a triangular object-based mesh. We introduce a novel “crack line” notion to deal with motion discontinuities and to improve representation scalability. The optimization of the nodal motion vectors is performed by means of a multi-resolution differential method, further improved by “backward in forward” tracking...

This paper introduces a mesh-based motion estimation scheme for image sequences and nodal motion vectors optimization by using a multi-resolution diieren-tial method. Because our nal aim is mesh tracking throughout a video sequence, neither backward tracking nor forward tracking is well suited. The backward tracking provides good results when simply applied to two successive images, but it is d...

Two dimensional mesh motion compensation produces blocking free prediction in contrast to block matching motion compensation by generating a smooth full motion field from the set of node motion vectors. This is clearly not appropriate across moving object boundaries where motion discontinuities exist. In this paper, we address this problem by proposing an adaptive interpolation scheme for patch...

This paper presents an efficient compression algorithm to encode the geometry of 3D mesh sequences with fixed connectivity. The proposed approach includes a temporal scan-based wavelet transform and motion compensation of the mesh geometry. Motion estimation/compensation is performed thanks to an efficient motion-based clustering approach The motion parameters are modeled by affine transforms m...

This paper proposes methods for designing, tracking and coding hierarchical 2D content-based mesh representations. The design procedure consists of constructing a ne-to-coarse hierarchy of Delaunay meshes, using image-and shape-based criteria for mesh geometry simpliication. Hierarchical tracking employs a coarse-tone strategy with mesh-based motion vector optimization. We introduce new techniq...

We consider problems involving high-speed moving rigid objects in a fluid flow. Instead of a more traditional deformable mesh approach, we describe a novel fixed mesh approach which use a level set function to implicitly track the fluid-solid interface, therefore no mesh motion or modification is required. The interface boundary conditions are also captured implicitly by combining a Ghost Fluid...

Existing schemes for 3-D Magnetic Resonance (MR) images, such as block matching method and uniform meshbased scheme, are inadequate to model the motion field of MR sequence because deformation within a mesh element may not all be similar. We propose a scheme consisting of (a) content-based mesh generation using optic flow between two consecutive images (b) forward motion tracking (c) motion com...

A new moving staggered mesh discretization for the numerical simulation of incompressible flow problems involving free-surfaces is presented. The method uses the staggered mesh to obtain speed and conservation properties. Mesh motion provides a high quality mesh in the interior and detailed resolution of the free-surface motion on the surface. Mesh flipping allows for optimal mesh connectivity ...