A progressive 3D mesh coding scheme using the octree-based space
partitioning is proposed in this work, which achieves better coding
efficiency than the state-of-the-art kd-tree-based codec. Given a 3D mesh, the quantized 3D vertices are first partitioned into an octree structure. The octree is then traversed from the root and gradually to the leaves. During the traversal, each 3D cell in the tree front is subdivided into eight child cells through three orthogonal cell bi-partitionings. For each cell subdivision, the information of nonempty child cells is encoded. To encode the information, two approaches (i.e. the bit-pattern coding approach and the nonempty-child-cell-tuple coding approach) are implemented and compared. In addition to the geometry coding, the local connectivity update associated with each cell subdivision is also encoded. Furthermore, selective cell subdivision is performed in the tree front to provide better rate-distortion performance, especially at low bitrates. It is shown in experimental results that the geometry coding cost is around 4.2 bits per vertex (bpv) for 8-bit coordinate quantization and 14.3 bpv for 12-bit coordinate quantization, and the connectivity coding cost is 3.3 bpv on the average.