Apparatus and method for coding a three dimensional mesh
Disclosed is a three-dimensional (3D) mesh compression apparatus and method. The 3D mesh compression apparatus may generate a base mesh through a mesh simplification, may separately compress the base mesh and vertices eliminated by the simplification, and may compress 3D mesh data based on the covariance matrix.
1. A method of compressing a 3D mesh, the method comprising:
simplifying a mesh by eliminating a plurality of vertices; and
generating a covariance matrix using the plurality of vertices, the generating comprising evaluating at least one topological distance among the plurality of eliminated vertices.
2. The method of claim 1 further comprising:
partitioning the simplified mesh into a plurality of segments.
3. The method of claim 2 , wherein each of the plurality of segments contains less than the predefined number of vertices.
4. The method of claim 1 , wherein the covariance matrix is
M
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1
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N
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ρ
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,
ρ denotes a correlation coefficient having a value equal or less than 1, and N ij denotes the at least one topological distance among the plurality of eliminated vertices.
5. The method of claim 1 further comprising:
calculating at least one eigenvector by performing eigen-vector decomposition of the covariance matrix.
6. The method of claim 1 further comprising:
calculating a coefficient of KL transform by using at least one eigenvector and at least one residual vector.
7. The method of claim 1 further comprising:
calculating a coefficient of KL transform by using y=U T x,
wherein x is a vector obtained from at least one residual vector, y is the coefficient of KL transform, and U has column vectors, which are the eigenvectors.
8. The method of claim 7 further comprising:
estimating the at least one residual vector.
9. The method of claim 7 further comprising:
quantizing the calculated coefficient of KL transform.
10. The method of claim 1 further comprising:
compressing the 3D mesh by using the covariance matrix.
11. A method of compressing a 3D mesh, the method comprising:
generating a simplified mesh by simplifying an inputted 3D mesh, thereby eliminating at least one vertex;
generating a covariance matrix using the at least one vertex; and
coding the simplified mesh thereby generating a bitstream comprising information regarding the simplified mesh, the information comprising connectivity information of the simplified mesh and geometric information of the simplified mesh.