Coding of Gaussian splats has drawn the attention of academia and standardization bodies lately. A commonly used approach involves projecting explicit 3D attributes onto 2D planes of a video and compressing it with existing video coding standards. However, such an approach produces excessively high sample rates, resulting in a significant bottleneck that might make it unsuitable for existing hardware decoders if the number of splats is high. This paper presents a framework that utilizes an implicit representation, where Gaussian splat attributes are represented by compact feature planes. By reducing the dependency of video resolution on the number of splats, our approach significantly reduces the required sample rate, making it suitable for deployed devices. In addition, the proposed framework achieves a superior rate-distortion trade-off, providing high-fidelity reconstruction at low bitrates without the excessive sample rates associated with the conventional video-based anchor.

We propose a complete system to enable progressive coding with quality scalability of the mesh geometry, in MPEG's state-of-the-art Video-based Dynamic Mesh Coding (V-DMC) framework. In particular, we propose an alternative method for encoding the subdivision wavelet coefficients in V-DMC, using a zerotree coding approach that works directly in the native 3D mesh space. This allows us to identify parent-child relationships amongst the wavelet coefficients across different subdivision levels, which can be used to achieve an efficient and versatile coding mechanism. We demonstrate that, given a starting base mesh, a target subdivision surface and a desired maximum number of zerotree passes, our system produces an elegant and visually attractive lossy-to-lossless mesh geometry reconstruction with no further user intervention. Moreover, lossless coefficient encoding with our approach requires nearly the same bitrate as the default displacement coding methods in V-DMC. Yet, our approach provides several quality resolution levels embedded in the same bitstream, while the current V-DMC solutions encode a single quality level only. To the best of our knowledge, this is the first time that a zerotree-based method has been proposed and demonstrated to work for the compression of dynamic time-varying meshes, and the first time that an embedded quality-scalable approach has been used in the V-DMC framework.

We present a method to super-resolve voxelized point clouds downsampled by a fractional factor, using lookup-tables (LUT) constructed from self-similarities from their own downsampled neighborhoods. The proposed method was developed to densify and to increase the precision of voxelized point clouds, and can be used, for example, as improve compression and rendering. We super-resolve the geometry, but we also interpolate texture by averaging colors from adjacent neighbors, for completeness. Our technique, as we understand, is the first specifically developed for intra-frame super-resolution of voxelized point clouds, for arbitrary resampling scale factors. We present extensive test results over different point clouds, showing the effectiveness of the proposed approach against baseline methods.