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Cloud gaming as the emerging game service has attracted significant attention. However, traditional video streaming approach suffers from high bandwidth consumption, and traditional graphics streaming approach requires a long initial period to download game models. In this paper, we propose a novel hybrid streaming framework, jointly applying video streaming and graphics streaming to provide a high-quality gaming experience. In the proposed framework, cloud servers not only transmit the encoded video frames but also progressively transmit the graphics data, which are used to render a game frame to provide an additional reference to the video encoder. Based on the proposed framework, we investigate the delay–rate–distortion optimization problem, where the source rate between the video stream and the graphics stream is optimized to minimize the overall distortion under the bandwidth and response delay constraints. The experimental results demonstrate that the proposed hybrid streaming can achieve the lowest distortion under the constraints of bandwidth and response delay, compared with the traditional video streaming and graphics streaming. [ABSTRACT FROM PUBLISHER]

The past few years have witnessed a dramatic growth in the number and variety of graphics intensive mobile applications, which allow users to interact and navigate through large scenes such as historical sites, museums and virtual cities. These applications support many clients and impose a heavy requirement on network resources and computational resources. One key issue in the design of cost efficient mobile walkthrough applications is the data transmission between servers and mobile client devices. In this paper, we propose an effective progressive mesh transmission framework that stores and divide scene objects into different resolutions. In this approach, each mobile device progressively receives and processes only the object’s details matching its display resolution which improves the overall system’s response time and the user’s perception. A fine grained cache mechanism is used to keep the most frequently requested objects’ details in the device memory and consequently reduce the network traffic. Experiments, in simulated and real world environment, are used to illustrate the effectiveness of the proposed framework under various settings of the virtual scene and mobile device configuration. Experimental results show that the proposed framework can improve the walkthrough system performance in mobile devices, with a relatively small overhead. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a new random accessible and progressive lossless manifold triangle mesh compression algorithm named POMAR. It allows to extract different parts of the input mesh at different levels of detail during the decompression. A smooth transition without artefacts is generated between adjacent regions decompressed at different levels of detail. Our approach allows selective decompression with low delay and compares favourably to previous random accessible and progressive schemes in terms of compression rates. [Copyright &y& Elsevier]

Abstract: This paper presents a new algorithm for the progressive compression of manifold polygon meshes. The input surface is decimated by several traversals that generate successive levels of detail through a specific patch decimation operator which combines vertex removal and local remeshing. The mesh connectivity is encoded by two lists of Boolean error predictions based on the mesh geometry: one for the inserted edges and the other for the faces with a removed center vertex. The mesh geometry is encoded with a barycentric error prediction of the removed vertex coordinates and a local curvature prediction. We also include two methods that improve the rate-distortion performance: a wavelet formulation with a lifting scheme and an adaptive quantization technique. Experimental results demonstrate the effectiveness of our approach in terms of compression rates and rate-distortion performance. [Copyright &y& Elsevier]

In computer graphics, animated models are widely used to represent time-varying data. And the progressive representation of such models can accelerate the speed of processing, transmission and storage. In this paper, we propose an efficient method to generate progressive animation models. Our method uses an improved curvature sensitive quadric error metric (QEM) criterion as basic measurement, which can preserve more local features on the surface. We append a deformation weight to the aggregated edge contraction cost during the whole animation to preserve more motion features. At last, we introduce a mesh optimization method for the animation sequence, which can efficiently improve the temporal coherence and reduce visual artifacts between adjacent frames. The results show our approach is efficient, easy to implement, and good quality progressive animation models can be generated at any level of detail. [ABSTRACT FROM AUTHOR]

Abstract: Tomographic imaging and computer simulations are increasingly yielding massive datasets. Interactive and exploratory visualizations have rapidly become indispensable tools to study large volumetric imaging and simulation data. Our scalable isosurface visualization framework on commodity off-the-shelf clusters is an end-to-end parallel and progressive platform, from initial data access to the final display. Interactive browsing of extracted isosurfaces is made possible by using parallel isosurface extraction, and rendering in conjunction with a new specialized piece of image compositing hardware called Metabuffer. In this paper, we focus on the back end scalability by introducing a fully parallel and out-of-core isosurface extraction algorithm. It achieves scalability by using both parallel and out-of-core processing and parallel disks. It statically partitions the volume data to parallel disks with a balanced workload spectrum, and builds I/O-optimal external interval trees to minimize the number of I/O operations of loading large data from disk. We also describe an isosurface compression scheme that is efficient for progress extraction, transmission and storage of isosurfaces. [Copyright &y& Elsevier]

Recently, CNC machining simulations require exponentially increasing computational time and memories of the computers, which have become a significant challenge for both computer hardware and software. This paper presents a novel geometric model for CNC machining simulations, which is called Level of details based on G-Code, or G-LODs for short. The G-LODs uses a type of progressive mesh to construct the surface simulation grid ( SSG). The SSG can be adopted to simulate the CNC machining processes at proper level of details. So theoretically simulations based on the G-LODs will not excessively occupy the computational and storage resources of computers. Based on the SSG, the G-buffer method is used to construct the solid model of the parts. The methodology of how to construct the G-LODs is established. In conclusion, several simulation examples based the G-LODs are presented. [ABSTRACT FROM AUTHOR]

Recently the application of signal and image processing techniques to polygonal meshes has attracted much attention in graphics. In this paper, the interesting reverse direction is considered; application of mesh processing techniques to images. We present a multiresolution representation of an image, called a progressive image, which is based on the progressive mesh representation. By applying mesh simplification to an image, we obtain a continuous hierarchy of image features from large to small scales. Multiresolution detail representation and the concept of dual pieces play an important role in performing feature processing with a progressive image. We demonstrate that a progressive image can be successfully applied to graphics problems concerning images, such as high dynamic range compression and painterly rendering. [ABSTRACT FROM AUTHOR]

Modern graphics cards are equipped with a vertex cache to reduce the amount of data needing to be transmitted to the graphics pipeline during rendering. To make effective use of the cache and facilitate rendering, it is key to represent a mesh in a manner that maximizes the cache hit rate. In this work, we propose a simple yet effective algorithm for generating a sequence for efficient rendering of 3D polygonal meshes based on greedy optimization. The algorithm outperforms the current state-of-the-art algorithms in terms of rendering efficiency of the resultant sequence. We also adapt it for the rendering of progressive meshes. For any simplified version of the original mesh, the rendering sequence is generated by adaptively updating the reordered sequence at full resolution. The resultant rendering sequence is cheap to compute and has reasonably good rendering performance, which is desirable to many complex rendering environments involving continuous rendering of meshes at various level of details. The experimental results on a collection of 3D meshes are provided. [ABSTRACT FROM AUTHOR]

Level Of Detail (LOD) modelling or mesh reduction has been found useful in interactive walkthrough applications. Progressive meshing techniques based on edge or triangle collapsing have been recognised useful in continuous LOD, progressive refinement, and progressive transmission. We present a vertex-collapsing mesh reduction scheme that effectively takes shape and feature preserving as well as material-discontinuity preserving into account, and produces a progressive mesh which generally has more vertices collapsed between adjacent levels of detail than methods based on edge-collapsing and triangle collapsing. [ABSTRACT FROM AUTHOR]

Abstract Progressive meshes are an established tool for triangle mesh simplification. By suitably adapting the simplification process, progressive hulls can be generated which enclose the original mesh in gradually simpler, nested meshes. We couple progressive hulls with a selective refinement framework and use them in applications involving intersection queries on the mesh. We demonstrate that selectively refinable progressive hulls considerably speed up intersection queries by efficiently locating intersection points on the mesh. Concerning the progressive hull construction, we propose a new formula for assigning edge collapse priorities that significantly accelerates the simplification process, and enhance the existing algorithm with several conditions aimed at producing higher quality hulls. Using progressive hulls has the added advantage that they can be used instead of the enclosed object when a lower resolution of display can be tolerated, thus speeding up the rendering process. ACM CSS: I.3.3 Computer Graphics—Picture/Image Generation , I.3.5 Computer Graphics—Computational Geometry and Object Modeling , I.3.7 Computer Graphics—Three-Dimensional Graphics and Realism. [ABSTRACT FROM AUTHOR]

This paper presents a novel progressive modelling algorithm for 3D models to generate progressive meshes. We propose a forest clustering simplification method to generate a progressive mesh of a model with the efficient and smooth transitions between meshes at different resolutions. Our approach can also integrate and balance the appearance attributes to preserve features of a model in the simplification process. We have applied our progressive modelling technique to several different kinds of input models and results show that our approach only generates efficient and smooth progressive meshes of a given model, but also preserves the features. The proposed method is very suitable for progressive transmission and real-time rendering of 3D models in networked virtual environments. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Arbitrary triangle mesh is a collection of 3D triangles without any shape or boundary restrictions. Progressive mesh (PM) is a multiresolution representation that defines continuous level of detail approximations for arbitrary triangle meshes. PM representation of a mesh can be processed to obtain a mesh approximation between the original and the base (simplified) mesh. Furthermore, PM can be refined in a view-dependent fashion to obtain a simpler mesh within a perceptual image quality. In this paper, we introduce an adaptation and improvements in our implementation for view-dependent refinement of progressive meshes. Essentially, we use a similar approach to Hoppe''s framework (ACM Comput. Graphics, Proceedings of SIGGRAPH’97, August 1997, pp. 189–198) for view-dependent refinement with a different algorithm for constructing PM representation. Our method is simple to implement and fast enough to achieve interactive frame rates for moderately complex models (models containing hundreds of thousands of polygons) on a machine with polygon rendering hardware. Moreover, our implementation allows changes to topology and achieves a simpler and sometimes more realistic refinements. [Copyright &y& Elsevier]

In this paper a new mesh simplification algorithm based on triangle collapses is presented. The algorithm can provide efficient error management and simplify the original mesh greatly. Progressive meshes may be constructed with triangle collapsing operation. To make continuous transition between level of detail (LOD) models possible, a method for interpolating is also presented. Examples illustrate the efficiency of the algorithm. [ABSTRACT FROM AUTHOR]