Patch-Based Mesh Coding with Bounding-Box Conversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing mesh coding methods do not efficiently utilize patch information, leading to suboptimal coding efficiency for 3D meshes, particularly in the context of scalable mesh coding and V-CG standards.
Innovation Solution
A method and apparatus that split a base mesh into multiple patches, applying static mesh coding on a patch basis, and convert vertex and UV coordinates using bounding box information in 3D and UV spaces to improve coding efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a base mesh is split into multiple patches for compression, then coding efficiency is improved, but device complexity increases due to additional patch management operations
Solution Approach 1:
The base mesh is divided into multiple patches, where each patch is processed independently for compression. This segmentation allows the encoder to apply optimization techniques locally to each patch, improving overall coding efficiency while managing complexity through modular processing
Solution Approach 2:
Different compression strategies and parameters can be applied to different patches based on their local characteristics. This allows the system to optimize coding efficiency for each region independently, handling complex geometries differently from simpler regions, thereby improving overall performance without uniformly increasing complexity across the entire mesh
2Loss of information
If coordinate values are transformed using bounding box information, then the dynamic range is reduced improving compression, but additional computational steps are required
Solution Approach 1:
The coordinate system parameters are transformed by applying bounding box information to each patch. This changes the reference frame from global coordinates to local patch-relative coordinates, reducing the dynamic range of values that need to be encoded and thereby improving compression ratio
Solution Approach 2:
Bounding box information is calculated and stored for each patch before the actual compression process. This preliminary action prepares the coordinate transformation data in advance, so that during compression, the system can directly apply these pre-computed bounds without performing complex real-time calculations, thus reducing the computational burden during the main encoding phase
Data Source
AI summary
A method and an apparatus are disclosed for patch-based mesh coding. In the disclosed embodiments, a mesh decoding device decodes a bitstream to reconstruct patch information and a patch-based base mesh. The mesh decoding device reconstructs base mesh vertices and connectivity by using the patch information and the patch-based base mesh. The mesh decoding device generates predicted vertices and connectivity based on the reconstructed base mesh vertices and connectivity. The mesh decoding device decodes a bitstream to reconstruct a transform-coefficient image, and reconstructs vector differences of vertices by unpacking, inverse quantizing and inverse transforming the transform-coefficient image. The mesh decoding device adds the predicted vertices and the vector differences to reconstruct mesh vertices and connectivity.