In this paper, we consider the problem of imaging a scene with a given depth of field at a given exposure level in the shortest amount of time possible. We show that by 1) collecting a sequence of photos and 2) contro...
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In this paper, we consider the problem of imaging a scene with a given depth of field at a given exposure level in the shortest amount of time possible. We show that by 1) collecting a sequence of photos and 2) controlling the aperture, focus, and exposure time of each photo individually, we can span the given depth of field in less total time than it takes to expose a single narrower-aperture photo. Using this as a starting point, we obtain two key results. First, for lenses with continuously variable apertures, we derive a closed-form solution for the globally optimal capture sequence, i.e., that collects light from the specified depth of field in the most efficient way possible. Second, for lenses with discrete apertures, we derive an integer programming problem whose solution is the optimal sequence. Our results are applicable to off-the-shelf cameras and typical photography conditions, and advocate the use of dense, wide-aperture photo sequences as a light-efficient alternative to single-shot, narrow-aperture photography.
Research on viewpoint in 3D scenes has been a cutting-edge subject in computer vision and 3D scene understanding. Calculating a high quality 3D viewpoint in virtual scenes is conducive to a more comprehensive analysis...
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Research on viewpoint in 3D scenes has been a cutting-edge subject in computer vision and 3D scene understanding. Calculating a high quality 3D viewpoint in virtual scenes is conducive to a more comprehensive analysis of 3D graphic structure, which can contribute to an overall understanding of virtual environments. 3D viewpoint research can also be applied to the analysis of structural relationships in virtual scenes and to exploit hidden hierarchical structures, thus it plays a role in fields such as scientific visualization computing or image-based scene modeling. Viewpoint research combined with relevant research results of human visual perception or visual psychology can be used to analyze the visual interest and focus areas of 3D objects in human vision, thus effectively improving the quality of mesh simplification and rendering efficiency, as well as providing an optimization basis for highly complex scenes. In fields such as 3D computer games, virtual reality, and landscape animation, research on high-quality viewpoints can be adopted to optimize global lighting and illumination. Additionally, practical applications can be realized through user attention analysis and aesthetic improvement strategies based on high-quality viewpoints, such as intelligent modeling and scene optimization calculations. In common fields such as 3D model retrieval, practical applications can be realized for saliency research, scientific visualization computing, and medical 3D imaging. In-depth research has been performed and extensive applications have been developed that make use of viewpoint analysis. In this paper, we introduce an optimization strategy to calculate high-quality virtual viewpoints for aesthetic images. A novel framework is proposed for modifying and optimizing the viewpoint calculation model by combining a multibranch CNN and a viewpoint correction method, thus realizing rendered images with a higher aesthetic quality. By attempting to fully integrate the visual p
Recent advances in high-resolution microscopy let neuroscientists acquire neural-tissue volume data of extremely large sizes. However, the tremendous resolution and the high complexity of neural structures present big...
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Recent advances in high-resolution microscopy let neuroscientists acquire neural-tissue volume data of extremely large sizes. However, the tremendous resolution and the high complexity of neural structures present big challenges to storage, processing, and visualization at interactive rates. A proposed system provides interactive exploration of petascale (petavoxel) volumes resulting from high-throughput electron microscopy data streams. The system can concurrently handle multiple volumes and can support the simultaneous visualization of high-resolution voxel segmentation data. Its visualization-driven design restricts most computations to a small subset of the data. It employs a multiresolution virtual-memory architecture for better scalability than previous approaches and for handling incomplete data. Researchers have employed it for a 1-teravoxel mouse cortex volume, of which several hundred axons and dendrites as well as synapses have been segmented and labeled.
The grid density requirements generally vary from problem to problem, hence interactive control over grid generation is required. While multi-block grids can be used to control the grid density globally, interactive m...
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The grid density requirements generally vary from problem to problem, hence interactive control over grid generation is required. While multi-block grids can be used to control the grid density globally, interactive mechanisms are required to carry out grid density manipulations locally. If we are able to accommodate an unequal number of grid points on opposite edges in a block, then this can be achieved with minimum manipulations in the neighbouring blocks. This also results in savings on the number of grid points. In this paper an algorithm for this is presented. A mechanism to control distribution of boundary points and the orientation of grid lines within a block, using simple algebraic expressions is also presented.
Focuses on the commercial usage of panoramic computer graphic images. Modification of illumination by image relighting; Effect of relighting techniques on light fine tuning; Application of an interactive Panorama View...
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Focuses on the commercial usage of panoramic computer graphic images. Modification of illumination by image relighting; Effect of relighting techniques on light fine tuning; Application of an interactive Panorama Viewer software in image feasibility demonstration; Use of a hardware graphics accelerator for real-time image magnification.
This paper presents a new technique called motion balance filtering, which corrects an unbalanced motion to a balanced one while preserving the original motion characteristics as much as possible. Differently from pre...
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This paper presents a new technique called motion balance filtering, which corrects an unbalanced motion to a balanced one while preserving the original motion characteristics as much as possible. Differently from previous approaches that deal only with the balance of static posture, we solve the problem of balancing a dynamic motion. We achieve dynamic balance by analyzing and controlling the trajectory of the zero moment point (ZMP). Our algorithm consists of three steps. First, it analyzes the ZMP trajectory to find out the duration in which dynamic balance is violated. Dynamic imbalance is identified by the ZMP trajectory segments lying out of the supporting area. Next, the algorithm modifies the ZMP trajectory by projecting it into the supporting area. Finally, it generates the balanced motion that satisfies the new ZMP constraint. This process is formulated as a constrained optimization problem so that the new motion resembles the original motion as much as possible. Experiments prove that our motion balance filtering algorithm is a useful method to add physical realism to a kinematically edited motion.
We present a system to combine arbitrary triangle mesh animations with physically based Finite Element Method (FEM) simulation, enabling control over the combination both in space and time. The input is a triangle mes...
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We present a system to combine arbitrary triangle mesh animations with physically based Finite Element Method (FEM) simulation, enabling control over the combination both in space and time. The input is a triangle mesh animation obtained using any method, such as keyframed animation, character rigging, 3D scanning, or geometric shape modeling. The input may be non-physical, crude or even incomplete. The user provides weights, specified using a minimal user interface, for how much physically based simulation should be allowed to modify the animation in any region of the model, and in time. Our system then computes a physically-based animation that is constrained to the input animation to the amount prescribed by these weights. This permits smoothly turning physics on and off over space and time, making it possible for the output to strictly follow the input, to evolve purely based on physically based simulation, and anything in between. Achieving such results requires a careful combination of several system components. We propose and analyze these components, including proper automatic creation of simulation meshes (even for non-manifold and self-colliding undeformed triangle meshes), converting triangle mesh animations into animations of the simulation mesh, and resolving collisions and self-collisions while following the input.
We present an automatic camera placement method for generating image-based models from scenes with known geometry. Our method first approximately determines the set of surfaces visible from a given viewing area and th...
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We present an automatic camera placement method for generating image-based models from scenes with known geometry. Our method first approximately determines the set of surfaces visible from a given viewing area and then selects a small set of appropriate camera positions to sample the scene from. We define a quality measure for a surface as seen, or covered, from the given viewing area. Along with each camera a position, we store the set of surfaces which are best covered by this camera. Next, one reference view is generated from each camera position by rendering the scene. Pixels in each reference view that do not belong to the selected set of polygons are masked out. The image-based model generated by our method, covers every visible surface only once, associating it with a camera position from which it is covered with quality that exceeds a user-specified quality threshold. The result is a compact non-redundant image-based model with controlled quality. The problem of covering every visible surface with a minimum number of cameras (guards) can be regarded as an extension to the well-known Art Gallery Problem. However, since the 3D polygonal model is textured, the camera-polygon visibility relation is not binary;instead, it has a weight - the quality of the polygon's coverage.
An enhanced differential chain coding (EDCC) scheme is developed for transmission of high-quality line graphics. Experiments showed that, compared to DCC with a resolution of the enhanced graphics adapter (EGA: 640x35...
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An enhanced differential chain coding (EDCC) scheme is developed for transmission of high-quality line graphics. Experiments showed that, compared to DCC with a resolution of the enhanced graphics adapter (EGA: 640x350pixels), EDCC with a resolution of 2100x1536 pixels gives a much higher quality with a modest extension in storage and transmission capacity.
The papers in this special section includes extended versions of four of the best papers presented at the 2012 ACM SIGGRAPH Symposium on Interactive 3D graphics and Games held from 9-11 March 2012 in Costa Mesa, Calif...
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The papers in this special section includes extended versions of four of the best papers presented at the 2012 ACM SIGGRAPH Symposium on Interactive 3D graphics and Games held from 9-11 March 2012 in Costa Mesa, California.
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