ITEM: Inter-Texture Error Measurement for 3D Meshes

We introduce a simple and innovative method to compare any two texture maps, regardless of their sizes, aspect ratios, or even masks, as long as they are both meant to be mapped onto the same 3D mesh. Our system is based on a zero-distortion 3D mesh unwrapping technique which compares two new adapted texture atlases with the same mask but different texel colors, and whose every texel covers the same area in 3D. Once these adapted atlases are created, we measure their difference with ITEM-RMSE, a slightly modified version of the standard RMSE defined for images. ITEM-RMSE is more meaningful and reliable than RMSE because it only takes into account the texels inside the mask, since they are the only ones that will actually be used during rendering. Our method is not only very useful to compare the space efficiency of different texture atlas generation algorithms, but also to quantify texture loss in compression schemes for multi-resolution textured 3D meshes

Practical global illumination for interactive particle visualization

ManuscriptParticle-based simulation methods are used to model a wide range of complex phenomena and to solve time-dependent problems of various scales. Effective visualizations of the resulting state will communicate subtle changes in the three-dimensional structure, spatial organization, and qualitative trends within a simulation as it evolves. We present two algorithms targeting upcoming, highly parallel multicore desktop systems to enable interactive navigation and exploration of large particle datasets with global illumination effects. Monte Carlo path tracing and texture mapping are used to capture computationally expensive illumination effects such as soft shadows and diffuse interreflection. The first approach is based on precomputation of luminance textures and removes expensive illumination calculations from the interactive rendering pipeline. The second approach is based on dynamic luminance texture generation and decouples interactive rendering from the computation of global illumination effects. These algorithms provide visual cues that enhance the ability to perform analysis and feature detection tasks while interrogating the data at interactive rates. We explore the performance of these algorithms and demonstrate their effectiveness using several large datasets

Optimization Of Frequency Filtering In Random Access Jpeg Library

In the paper we present a method of direct access to single blocks of JPEG files whichcontain textures, with on-the-fly decompression. Anisotropic, adaptive filtering is applied inorder to minimize visual defects appearing mainly on blocks borders. Main purpose of themethod is to enable fast extraction of only these parts of an entire image which are currentlyneeded and not to keep whole decompressed texture in the main memory. This approachenables effective usage of high quality textures with low memory consumption. It’s benefitsare mainly demonstrated in rendering complex 3D scenes using nondeterministic ray-tracingalgorithm. The algorithms have been encapsulated into DLL and static library

New approaches to texture coding in segmentation and feature-based image coding schemes

Peer ReviewedPostprint (published version

Using Graphics Processor Units (GPUs) for automatic video structuring

The rapid pace of development of Graphic Processor Units (GPUs) in recent years in terms of performance and programmability has attracted the attention of those seeking to leverage alternative architectures for better performance than that which commodity CPUs can provide. In this paper, the potential of the GPU in automatically structuring video is examined, specifically in shot boundary detection and representative keyframe selection techniques. We first introduce the programming model of the GPU and outline the implementation of techniques for shot boundary detection and representative keyframe selection on both the CPU and GPU, using histogram comparisons. We compare the approaches and present performance results for both the CPU and GPU. Overall these results demonstrate the significant potential for the GPU in this domain

Topographic map visualization from adaptively compressed textures

Raster-based topographic maps are commonly used in geoinformation systems to overlay geographic entities on top of digital terrain models. Using compressed texture formats for encoding topographic maps allows reducing latency times while visualizing large geographic datasets. Topographic maps encompass high-frequency content with large uniform regions, making current compressed texture formats inappropriate for encoding them. In this paper we present a method for locally-adaptive compression of topographic maps. Key elements include a Hilbert scan to maximize spatial coherence, efficient encoding of homogeneous image regions through arbitrarily-sized texel runs, a cumulative run-length encoding supporting fast random-access, and a compression algorithm supporting lossless and lossy compression. Our scheme can be easily implemented on current programmable graphics hardware allowing real-time GPU decompression and rendering of bilinear-filtered topographic maps.Postprint (published version

Lossless Compression for Semantic Textures

A semantic texture overlays semantic labels over an image to indicate the type of texture represented by each region of the image. Traditional lossy compression works well for color textures, but not for semantic textures. This disclosure describes lossless compression techniques to compress semantic textures, thereby reducing the memory occupied by semantic textures. The techniques leverage the observation that semantic textures, unlike color textures, are highly structured with large blocks of common values. The techniques enable high-speed access to detailed rendering and resolution in real-time computer graphics. They also enable additional textures or texture resolution, enhancing the detail and realism of rendering