Region-of-Interest Coding Of 3D Mesh

Compared with other media such as text, voice, image and video, the 3D graph is more vivid and compatible with the visual habits of people in the world. Recently, with the rapid development of Internet and the progress of 3D scanning technique, users can share 3D models through network easily in future. However, the data amount of 3D graph is usual huge, the compression of 3D models is necessary consequently. On the other hand, users may be more interested with a partial region of the 3D mesh in some cases, and wish the region-of-interest (ROI) decoded more quickly with better quality than the rest regions. However, traditional 3D mesh coding methods waste the limited source because the ROI have not been distinguished from the non-ROI. If the limited source can be distributed to ROI firstly, transmission time and network bandwidth can be much saved. Although ROI coding has been a hot topic in image and video research, there has not been any report about ROI coding on 3D mesh yet. 3D compression is combined with ROI coding in this paper, and an effective method of ROI coding of 3D mesh is proposed. Firstly, a mesh with irregular connectivity is remeshed into a semi-regular mesh, and wavelet transform decomposes the semi-regular mesh into a base mesh and a series of wavelet coefficients. The base mesh is compressed with non-progressive compression method, and the coefficients are coded with modified SPIHT (Set Partitioning in Hierarchical Trees) algorithm after shifting up the bit-planes of coefficients in ROI mask. Arithmetic Coding is used for further compression at last. A method of constructing ROI mask and two priority strategies of ROI coding are proposed in this paper. The two priority strategies are general shifting-up method and max shifting-up method respectively. The SPIHT algorithm is modified for ROI coding of 3D mesh. Combined different methods of specifying ROI with two priority strategies, four coding/decoding models are proposed in this paper. The proposed ROI coding of 3D mesh has been proved effective according to the...