An efficient connectivity compression for triangular meshes

Edgebreaker and valence-driven approaches use split operations to separate the 3D model into two components. These algorithms raise some bottlenecks for spending increased overheads to record the displacement, or an extra operator is needed for identifying the branch. This study applies an edge-based compression strategy, and proposes using the J operator to skip to the next edge of the active boundary. By using Q operator, two triangles are encoded to improve compression ratio. Additionally, the method requires neither splitting model topology nor multiple passes to achieve a good compression rate. To increase the compression ratio, the adaptive arithmetic coder was applied to compress the CQRU string. The experimental results demonstrate that an excellent compression ratio can be obtained, the average compression ratio with the proposed model is better than that with the valence-driven and Edgebreaker methods. The entropy/compression ratio relation curve of the variance-driven method has strong vibration, and the proposed algorithm exhibits coherent tendency. The proposed algorithm has a fixed number and value distribution of operators, and thus only considers the context between operators in achieving the best compression ratio.