16066042
Level-of-detail representation of bidirectional texture functions for real-time rendering
This paper presents a new technique for rendering bidirectional texture functions (BTFs) at different levels of detail (LODs). Our method first decomposes each BTF image into multiple subbands with a Laplacian pyramid. Each vector of Laplacian coefficients of a texel at the same level is regarded as a Laplacian bidirectional reflectance distribution function (BRDF). These vectors are then further compressed by applying principal components analysis (PCA). At the rendering stage, the LOD parameter for each pixel is calculated according to the distance from the viewpoint to the surface. Our rendering algorithm uses this parameter to determine how many levels of BTF Laplacian pyramid are required for rendering. Under the same sampling resolution, a BTF gradually transits to a BRDF as the camera moves away from the surface. Our method precomputes this transition and uses it for multiresolution BTF rendering. Our Laplacian pyramid representation allows real-time anti-aliased rendering of BTFs using graphics hardware. In addition to provide visually satisfactory multiresolution rendering for BTFs, our method has a comparable compression rate to the available single-resolution BTF compression techniques.
9625222
Real-Time Rendering of Watercolor Effects for Virtual Environments
In this paper, we present an empirical approach for rendering realistic watercolor effects in real-time. While watercolor being a versatile media, several characteristics of its effects have been categorized in the past. We describe an approach to recreate these effects using the Kubelka-Munk compositing model and the Sobel filter. Using modern per-pixel shading hardware, we present a method to render these effects in an interactive frame-rate.
1331907
An efficient representation of complex materials for real-time rendering
In this paper, we propose an appearance representation for general complex materials which can be applied in real-time rendering framework. By combining a single parametric shading function (such as the Phong model) and the proposed spatial-varying residual function (SRF), this representation can recover the appearance of complex materials with little loss of visual fidelity. The difference between the real data and the parametric shading is directly fitted by a specific function for easy reconstruction. It is simple, flexible and easy to be implemented on programmable graphics hardware. Experiments show that the mean square error (MSE) between the reconstructed appearance and real photographs is less than 5%.
18329174
Enhancing 3D Graphics on Mobile Devices by Image-Based Rendering
Compared to a personal computer, mobile devices typically have weaker processing power, less memory capacity, and lower resolution of display. While the former two factors are clearly disadvantages for 3D graphics applications running on mobile devices, the display factor could be turned into an advantage instead. However the traditional 3D graphics pipeline cannot take advantage of the smaller display because its run time depends mostly on the number of polygons to be rendered. In contrast, the run time of image-based rendering methods depends mainly on the display resolution. Therefore it is well suited for mobile devices. Furthermore, we may use the network connection to build a client-server framework, which allows us to integrate with nonimage-based rendering programs. We present our system framework and the experiment results on PocketPC® based devices in this work.
14948724
Joint software research between industry and academia
A model for industry-sponsored academic software research tha helps the sponsor gain tangible results quickly but respects the university's research mission is presented. Central to the model is joint effort to achieve a win-win situation for all participants. The key is the relationship between the university's principal investigator and the company's visiting scholar. The principal investigator initiates research contracts and is responsible for research results but, because he or she is an academic, may not have an industrial perspective. The company dispatches a technical representative, called the visiting scholar, to participate directly in the daily research. A research structure, relations with the sponsoring company, issues regarding environmental compatibility and funding amount and duration, and a reporting structure are all spelled out in the model. Legal recommendations are made with respect to confidentiality, copyrights and patents, export controls, and other issues. Other considerations that arise when writing a research contract are discussed.<<ETX>>
12945067
A Fast Search Algorithm for Vector Quantization
285,641. British Celanese, Ltd., and Olpin, H. C. Feb. 9, 1927. Samples furnished. Anthraquinone derivatives.-Sulphuric esters of anthraquinonylamino alcohols, which are dyestuffs for organic substitution products of cellulose, e.g. cellulose esters and ethers, and for animal fibres, are made by treating the corresponding alcohols with sulphuric acid or oleum; or by the action of sulphuric esters of aminoalcohols on leuco oxyanthraquinones, e.g. the leuco compounds of 1-oxy-, 1 : 4-dioxy-, 1 : 4 : 5- trioxy or 1 : 4 : 5 : 8-tetraoxy-anthraquinone, followed by oxidation of the leuco body; or by replacement of chlor, nitro, methoxy &c. groups by treatment with sulphuric esters of aminoalcohols, e.g. #-aminoethyl alcohol. The anthraquinonylamino alcohols, for treatment with sulphuric acid or oleum, may be obtained by treating amino or mono-substituted amino derivatives of anthraquinone or substituted anthraquinones with halohydrins, e.g. ethylene, propylene or glyceryl chlorhydrins, epichlorhydrin, or chlorbutylene glycol, or with alkylene oxides, e.g. ethylene or propylene oxide, or with oxyaldehydes or ketones, or by replacement of chlor, nitro, hydroxy, methoxy &c. groups by treatment with an amino alcohol. The sulphuric esters of 1-#-oxyethylamino-, 1-#-oxyethylamino-2 (and 4)- methyl-, 1-#-oxyethylamino-4-oxy (and amino)-, 1-#-oxyethylamino-2-brom-4-amino-, and 1 : 4- and 1: 5-di-#-oxyethylamino-anthraquinones are specified.
33039704
A circular skip-cluster scheme to support video-on-demand services
Abstract. The major drawback of the existing cluster placement scheme is the long response time caused by admission control if the number of clusters and the number of users are large. A circular skip-cluster placement scheme is proposed to reduce the size of the data buffer as well as the system response time. Furthermore, the popularity of each video is different in the real world. We propose a new popularity-based data allocation scheme to allocate data units within a cluster such that the corresponding data units of these popular videos are stored in those cylinders at one end of each cluster. Due to a higher spatial locality within these hot cylinders, some data units requested by the users are stored in the same cylinder such that one seek operation, one rotation, and one transfer operation are required to retrieve these data units. Therefore, the time required to retrieve data for these requests can be reduced, thus also reducing the system response time. Based on our results, the buffer size and the system response time can be reduced by half or more. These findings are essential for constructing video-on-demand systems that provide satisfactory performance.
11560314
Distributed systems design using function-class decomposition with aspects
Object-oriented methods are known for their capabilities to encapsulate and manage core concerns of complex software systems. However, they are inadequate in discerning and separating a variety of other cross-cutting concerns. In particular, for distributed systems, a number of important concerns such as synchronization, logging, and security, should be sufficiently treated in the design phase of the software lifecycle in order to ensure high system quality. Often these concerns tend to be overlooked at the design level and consequently scattered across multiple system modules during implementation. Consequently it becomes difficult to connect the set of requirements with the system structure, thus system traceability is reduced. This paper proposes an extension to the function-class decomposition (FCD) method, that is a hybrid method of structured analysis and OO approach, by integrating the concepts of "aspect". "Aspect" is an abstraction mechanism that emerged in recent years from the aspect-oriented programming (AOP) community. This extended method supports separation of functional and non-functional concerns by maintaining two primary views (function-class view and aspect view) at the design stage, and demonstrates the iterative process by applying it to the development of an example system called M-Net that is an Internet-based real-time distributed conferencing system.
358297
LDI tree: a hierarchical representation for image-based rendering
Using multiple reference images in 3D image warping has been a challenging problem. Recently, the Layered Depth Image (LDI) was proposed by Shade et al. to merge multiple reference images under a single center of projection, while maintaining the simplicity of warping a single reference image. However it does not consider the issue of sampling rate. We present the LDI tree, which combines a hierarchical space partitioning scheme with the concept of the LDI. It preserves the sampling rates of the reference images by adaptively selecting an LDI in the LDI tree for each pixel. While rendering from the LDI tree, we only have to traverse the LDI tree to the levels that are comparable to the sampling rate of the output image. We also present a progressive refinement feature and a “gap filling” algorithm implemented by pre-filtering the LDI tree. We show that the amount of memory required has the same order of growth as the 2D reference images. This also bounds the complexity of rendering time to be less than directly rendering from all reference images. CR Categories: I.3.3 [Computer Graphics]: Picture/Image Generation Viewing Algorithms; I.3.6 [Computer Graphics] Methodology and Techniques Graphics data structures and data types; I.3.7 [Computer Graphics]: Three-Dimensional Graphics and Realism. Additional