Back to grail.html
General info
People and collaborators
Main current research projects
Image gallery

Angle-Analyzer: A Triangle-Quad Mesh Codec
Haeyoung Lee, Pierre Alliez, and Mathieu Desbrun. 
Eurographics 2002 Conference Proceedings



A Single-Rate Compression Algorithm, Angle-Analyzer, for a triangle-quad mesh has been introduced. Only 5 symbols were defined to encode connectivity of an arbitrary triangle mesh with any genus, holes, and boundaries. (8 symbols for a Quad mesh and 12 symbols for a hybrid of triangle/quad mesh) A noble Geometry-driven adaptive traversal was designed to reduce the occurrences of special symbol and generated a low entropy sequence of symbols. Localized approaches with an irregular grid for adaptive quantizations to encode geometry were also created. As a result, with the same or less level of distortion, measured by a tool Metro, our Angle-Analyzer could generate on average 20% better compression ratios than the current leading Touma and Gotsman's algorithm with 12-bit quantization applied.

Contribution to Connectivity Coding
Fixed number of symbols defined
New geometry-driven adaptive traversal
Triangle, quad, hybrid of triangle/quad meshes
Contribution to Geometry Coding
New intrinsic and extrinsic angle encoding
New local coordinate systems
Entropy-driven quantization