Areas Of Graphics Research Articles

User-drawn sketch-based 3D object retrievalusing sparse coding

3D object retrieval from user-drawn (sketch) queries is one of the important research issues in the areas of pattern recognition and computer graphics for simulation, visualization, and Computer Aided Design. The performance of any content-based 3D object retrieval system crucially depends on the availability of effective descriptors and similarity measures for this kind of data. We present a sketch-based approach for improving 3D object retrieval effectiveness by optimizing the representation of one particular type of features (oriented gradients) using a sparse coding approach. We perform experiments, the results of which show that the retrieval quality improves over alternative features and codings. Based our findings, the coding can be proposed for sketch-based 3D object retrieval systems relying on oriented gradient features.

3D human motion analysis framework for shape similarity and retrieval

3D shape similarity from video is a challenging problem lying at the heart of many primary research areas in computer graphics and computer vision applications. In this paper, we address within a new framework the problem of 3D shape representation and shape similarity in human video sequences. Our shape representation is formulated using extremal human curve (EHC) descriptor extracted from the body surface. It allows taking benefits from Riemannian geometry in the open curve shape space and therefore computing statistics on it. It also allows subject pose comparison regardless of geometrical transformations and elastic surface change. Shape similarity is performed by an efficient method which takes advantage of a compact EHC representation in open curve shape space and an elastic distance measure. Thanks to these main assets, several important exploitations of the human action analysis are performed: shape similarity computation, video sequence comparison, video segmentation, video clustering, summarization and motion retrieval.Experiments on both synthetic and real 3D human video sequences show that our approach provides an accurate static and temporal shape similarity for pose retrieval in video, compared with the state-of-the-art approaches. Moreover, local 3D video retrieval is performed using motion segmentation and dynamic time warping (DTW) algorithm in the feature vector space. The obtained results are promising and show the potential of this approach.

An Art Gallery Approach to Submap Meshing

The Art Gallery Theorem and its lemmas have been used since the 1990s in the area of computer graphics to decompose orthogonal polygons into convex sub-regions. This paper extends and improvises Art Gallery concepts to non-orthogonal, generic polygons to perform a multiblock decomposition of faces into a set of maximal, single-loop, convex sub-faces. Concepts such as staircase, dent and notch are used to categorize face concavities and virtual vertices are inserted on smoother concave boundary bends. Multiblocking is performed without the need for Delaunay triangulation with the aid of a notch diagram. A light-weight, mesher-native topology builder that uses virtual topological elements is proposed to construct a virtual topology network from a notch diagram. Subsequently, virtual faces are processed for transfinite meshing. Results indicate the advantage of the proposed technique over existing procedures in terms of orthogonality and anisotropy.

FDS Simulation High Rise Building Model for Unity 3D Game Engine

Smoke simulation is an interesting topic in simulation fluid dynamics and graphics area. Stack Effect Fire model was happened in fire of High Rise building. Simulation this fire model and smoke scene is one of the most challenging tasks in fluid dynamics of computer graphics area. In this paper proposed Smoke simulation rendering is based on game engine of particle system. But common game engine don’t have stack effect model and compute coordinate position algorithm. Recently proposed method based on FDS’s (Fire Dynamic Simulation) result Excel file which improves Unity 3D game engine for stake effective fire model and smoke boundaries. Using Excel file coordinates to improve Unity 3D game engine particle system, and changes the original game engine particle system, over the coordinates of particles moving location, boundary and fire model stake effect look like real world fire model. Recently game engine computer graphic researcher usually control computing resources focused on smoke visualization skip fire effect and physically problem. In this paper, need focused on smoke location boundary and fire model stake effect. The proposed method can change smoke and fire model of stack effect and particles more accurately and efficiently than other, rendering is implemented by making smoke particles and physically effect. After putting the coordinate form FDS into Unity3D game engine Experiment performance result shows particles more look like reality, and gives neutrality and reality to user's view. This algorithm problem is from simulation high rise building mesh with loading time need more computer resource, and need to change some effect in Unity 3D game asset.

Honoring the code: conversations with great game designers

If you want to be successful in any area of game development-game design, programming, graphics, sound, or publishing-you should know how standouts in the industry approach their work and address problems. In Honoring the Code: Conversations with Great Game Designers, 16 groundbreaking game developers share their stories and offer advice for anyone

Techniques of Facial Synthesis: A Comprehensive Literature Review

As an important area of computer graphics, realistic image synthesis provides principles and techniques for creating realistic imagery through computations based upon models of real-world objects and behaviors. Facial expression is one of the primary communication means of the human. The ultimate goal of realistic image synthesis is to achieve perfect realism -the synthesized images are visually indistinguishable from their real-world counterparts. This area has widespread applications in industry and scientific research including 3D design, omputer animation, scientific visualization and virtual reality Facial expression synthesis has many useful applications in practice. How to synthesize facial expression images robustly and simply is still a challenging problem. This paper surveys the state of the art in this area.

Modeling of Objects Using Conic Splines

This paper contributes towards modeling for the designing of objects in the areas of Computer Graphics (CG), Computer-Aided Design (CAD), Computer-Aided Manufacturing (CAM), and Computer-Aided Engineering (CAE). It provides a modeling technique for the designing of objects. The model is based on a conic-like curve (rational quadratics) method and provides an extra degree of freedom to the user to fine tune the shape of the design to the satisfactory level. The 2D curve model has then been extended for the designing of 3D objects to produce fancy objects. The scheme has been also extended to automate the degree of freedom when a reverse engineering is required for images of the objects. A heuristic technique of genetic algorithm is applied to find optimal values of shape parameters in the description of conics.

Use of XML Schema and Logic Programming Views as Formal Means to Validate A System Design Framework

The continuous complexity increase of today’s embedded systems and portable computing machines has motivated research in the area of h igh-level and system synthesis (HLS). In this paper’s prototype system design framework, the HLS internal formats and transformations that are applied on the source code are formal, thus the generated system implementation is correct-by-construction. Here, the use of RDF triples for making statements about Web resources is extended for the formal definit ion of the internal object relations and predicated formal transformation of the prototype hardware compiler. Th is pro totype HLS framework uses compiler-generators, RDF rules and logic programming in combination with XML validation mechanisms for the internal state of the hardware compiler. All of these formal relations make the compilation process formal, and thus, the generated implementations are provably-correct. Furthermore, the compilat ion run-time doesn’t exceed a few minutes for the most complex benchmarks. The design framework is enhanced with the Parallel, Abstract Resource – Constrained Scheduler (PARCS), which ach ieves “compression” of the initial schedules to optimized ones up to a degree o f more than 30% of the control states. The targeted architecture is free from any vendor/technology – specific templates and implementation specifics, thus the automatically-generated hardware models are directly implementable on any technology and with any RTL synthesizer and Place&Route flow. A ll of the required communication protocols and interfaces are automatically generated and embedded into the hardware’s model code. The complete design informat ion of the HLS process is formally validated with the logic programming and XML views of the internal state of the compiler. The aggressive scheduler PARCS and the formal compilation of the system are evaluated with a number o f benchmarks and real -world applications, from the areas of computer graphics, DSP, image processing/compression and synthetic benchmarks.

Singularities of a Space Curve according to the Relatively Parallel Adapted Frame and Its Visualization

The relatively parallel adapted frame or Bishop frame is an alternative approach to define a moving frame that is well defined even when the curve has vanished second derivative, and it has been widely used in the areas of biology, engineering, and computer graphics. The main result of this paper is using the relatively parallel adapted frame for classification of singularity type of Bishop spherical Darboux image and Bishop dual which are deeply related with a space curve and making them visualized by computer.

Avatar interoperability and control in virtual Worlds

Virtual worlds (VWs), and especially the ones using 3D graphics content, have been massively developed and deployed over the last few years. Technological developments, both in hardware and software, bring up significant improvements in the areas of display, graphics, animation, distributed systems, network and mobile phones technology. These improvements allow almost every user on Web 2.0 to have a representation in different VWs. In those VWs, avatars have a specific place, representing a graphical appearance of human beings and a container for the users’ specific data. Therefore, the need to reuse them across different VWs and across different platforms increases significantly.In this paper we are presenting a framework that allows interoperability of avatars between VWs. The proposed method consists of considering the avatar as a combination of a template and a set of characteristics that personalizes the template. The former, which is specific to each VW, can remain proprietary; the latter will be exchanged between the VWs. Therefore, the proposed solution is equilibrating the interests of end-users and VWs providers, allowing to not recreate an avatar for each VW and ensuring that user-defined avatars are consistent with the VW, technically- and businesswise.

Real-Time GPU Surface Curvature Estimation on Deforming Meshes and Volumetric Data Sets

Surface curvature is used in a number of areas in computer graphics, including texture synthesis and shape representation, mesh simplification, surface modeling, and nonphotorealistic line drawing. Most real-time applications must estimate curvature on a triangular mesh. This estimation has been limited to CPU algorithms, forcing object geometry to reside in main memory. However, as more computational work is done directly on the GPU, it is increasingly common for object geometry to exist only in GPU memory. Examples include vertex skinned animations and isosurfaces from GPU-based surface reconstruction algorithms. For static models, curvature can be precomputed and CPU algorithms are a reasonable choice. For deforming models where the geometry only resides on the GPU, transferring the deformed mesh back to the CPU limits performance. We introduce a GPU algorithm for estimating curvature in real time on arbitrary triangular meshes. We demonstrate our algorithm with curvature-based NPR feature lines and a curvature-based approximation for an ambient occlusion. We show curvature computation on volumetric data sets with a GPU isosurface extraction algorithm and vertex-skinned animations. We present a graphics pipeline and CUDA implementation. Our curvature estimation is up to ~18x faster than a multithreaded CPU benchmark.

How surface roughness affects the angular dependence of the sputtering yield

Comprehensive model is developed to study the impact of surface roughness on the angular dependence of sputtering yield. Instead of assuming surfaces to be flat or composed of exact self-similar fractals, we developed a new method to describe the surfaces. Random fractal surfaces generated by midpoint displacement algorithm in computer graphics area and Support vector machine algorithm in pattern recognition area are combined with the Monte Carlo ion bombardment simulation code, i.e., Ion Transport in Materials and Compounds (ITMC) code [1]. With this new fractal version of ITMC-F, we successfully simulated the angular dependence of sputtering yield for various ion-target combinations. Examples are given for 5keV Ar ions bombarding iron, graphite, and silicon surfaces, with the input surface roughness exponent directly depicted from experimental data. Comparison is made with previous models to account for surface roughness and recent experimental data. The ITMC-F code showed good agreement with the experimental data.

Sparse coding based feature optimisation for robust 3D object retrieval

3D object retrieval is an important research issue in the area of computer graphics for applications such as computer-aided design, simulation, and visualisation. The performance of 3D object retrieval systems is dependent on the development of efficient and effective descriptors and similarity measures. Presented is an effective approach for supporting 3D object retrieval based on optimising the gradient descriptor which has recently been shown to perform among the state of the art. The approach relies on sparse coding and the effectiveness of the method is demonstrated by experimental evaluation.

LApIS: developing research applied to health care area

The Laboratory of Computer Applications for Health Care is a Brazilian lab researching in the virtual reality, Content-based image retrieval, and image processing areas, mainly developing applications to the health care area, although many of the techniques and tools extrapolate this application scope. . In this paper we present a brief history of the laboratory, its mission as well as current projects and collaborations. All the projects developed at LApIS have some relevant aspects for researches in the graphics area, which can become new opportunities for student’s integration and new collaborations.

The use of Photoshop software to estimate the adhesion and rust‐resistant properties of coating film

AbstractA new method for evaluating the adhesion and rust‐resistant properties of coating film is proposed and validated by Photoshop software. A color scanner and Photoshop processing software are used to scan coatings film and analyze images by this method. The percentage of film area removed calculated by pixels is used to classify adhesion of the cross‐cut test ASTM D3359. The area removed is measured by using the functions of area selection and histogram in Photoshop software. The adhesion of 14 samples about standard classification pictures of crosscut adhesion test of ASTM D3359‐02 and self‐made samples, are classified. The percent area removed given by ASTM standard and the percent pixels removed measured by Photoshop is correlated, with the correlation coefficient being 0.997. On the other hand, the rusty areas of regular and irregular graphics are quantitatively determined using $A' = {X'\over X}\times A$ to estimate the rust resistant properties. The determining error of rusty areas compared with the vernier caliper is under 3.0%. Quantitative evaluation for extent of corrosion of the coating is realized. The method is more scientific and specific than the present method of that evaluated by the human mind. Copyright © 2010 John Wiley & Sons, Ltd.

Cloud Theory and Fractal Application in Virtual Plants

Plants is an important component of natural scene. Unfortunately, due to high level complexity of the structure of plant, simulating plant becomes extremely a difficult task. When the fractal theory is imported, it provides a broader development space for the plant modeling. With the development of the fractal research, virtual plant has become a hot and interesting research topic in computer graphics area. The virtual plants technology is very important in guiding the crop production, implementing the agriculture informationization and constructing the virtual environment. At present a single virtual plant modeling technology is quite mature, the method to generate a body of plants often uses the even algorithm or the normal algorithm, but a body of plants in the real world is not even, and is not normal also, the cloud model relaxes the precise determination membership function to expectation function with normal distributed membership degree, combines ambiguity and randomness organically to fit the real world objectively. So it has general applicability, producing a body of plants based on the cloud model can simulate plant's condition and the distribution well.

A Perception Correlated Comparison Method for Dynamic Meshes

There are multiple areas of computer graphics where triangular meshes are being altered in order to reduce their size or complexity, while attempting to preserve the original shape of the mesh as closely as possible. Recently, this area of research has been extended to cover even a dynamic case, i.e., surface animations which are compressed and simplified. However, to date very little effort has been made to develop methods for evaluating the results, namely the amount of distortion introduced by the processing. Even the most sophisticated compression methods use distortion evaluation by some kind of mean squared error while the actual relevance of such measure has not been verified so far. In this paper, we point out some serious drawbacks of the existing error measures. We present results of the subjective testing that we have performed, and we derive a new measure called Spatiotemporal edge difference (STED) which is shown to provide much better correlation with subjective opinions on mesh distortion.

Deterministic Blue Noise Sampling by Solving Largest Empty Circle Problems

〈Summary〉 Sampling patterns with a blue noise distribution are widely used in many areas of computer graphics, yet their efficient generation remains a difficult problem. We propose a method to generate point sets with a blue noise distribution using a deterministic algorithm with no preprocessing. We insert each new sample at the center of the largest empty circle in the point set, which is obtained by calculating the Delaunay-triangulation of the set and finding the triangle with the largest circumcircle. Our method supports adaptive sampling according to a user-specified density function, as well as specifying the exact number of required samples. It can also be extended to perform sampling on a three-dimensional curved surface.

FAST GENERATION OF DEMOLITION SPECIAL EFFECTS ON 3D BUILDINGS

Creating natural, controllable, and efficient computer-generateddemolition effects has become a challenging goal in the area of computergraphics. Such effects are of great use in diverse areas that include videogames, computer animation, and special effects in action films.Unfortunately, creating such effects is become complicated and timeconsumingdue to the demolition's natural complex movements and itsrelated effects that include fragmentation, fog, debris, collapsed walls,and dust. To generate realistic demolition special effects, there are twowell-known approaches, manual and destruction simulations. Themanual approach relies on choosing appropriate tools and setting itsparameters to achieve the desired level of realism. However, thisapproach requires a long time and effort from the designers. On the otherhand, the destruction simulations depend on the nature of the demolishedobjects. However, this approach is slow due to the complexity ofsimulating the physical behavior of the destructed objects and the energyproduced by the collisions between them. The proposed method is basedon the automation of the manual approach which depends on creatingthe effect through programming a script, list of instructions, to generatebelievable and compelling demolition effect in a fast manner.

Scene Reconstruction and Visualization from Internet Photo Collections: A Survey

The Internet has become an unprecedented source of visual information about our world, with millions of people uploading photos and videos to media-sharing sites at staggering rates. Virtually all of the world's famous landmarks and cities (and many not-so-famous ones) have been photographed hundreds of thousands or millions of times, and billions of these photos can be found on photo-sharing websites. This richness and variety make such Internet photo collections extremely attractive as a source of data for applications ranging from mapping and visualization to social science. However, a prerequisite to many such applications is recovering structure — often in the form of 3D geometry — from these massive, unorganized collections of imagery. This ever-growing collection of visual data opens up fundamental new questions in computer vision and computer graphics, where traditional techniques designed for small, controlled sets of images cannot be readily applied. This article surveys recent work on applying geometric computer vision to large, unstructured photo collections, as well as applications enabled by these new techniques in scene visualization, location recognition, image editing, and other areas of computer vision and graphics.