Surface Completion Using Laplacian Transform

Model acquisition process usually produce incomplete surfaces due to the technical constrains. This research presents the algorithm to perform surface completion using the available surface's context. Previous works on surface completions do not handle surfaces with near-regular pattern or irregular patterns well. The main goal of this research is to synthesize surface for hole that will have similar surface's context or geometric details as the hole's surrounding. This research uses multi-resolution approach to decompose the model into low-frequency part and high-frequency part. The low-frequency part is filled smoothly. The high-frequency part are transformed it into the Laplacian coordinate and filled using example-based synthesize approach. The algorithm is tested with planar surfaces and curve surfaces with all kind of relief patterns. The results indicate that the holes can be completed with the geometric detail similar to the surrounding surface

Explicit Energy-Minimal Short-Term Path Planning for Collision Avoidance in Crowd Simulation

In traditional crowd simulation methods, global path planning (GPP) and local collision avoidance (LCA) were mostly used to advance pedestrians toward their own goals without colliding. However, we found that using those methods in bidirectional flows can force a pedestrian to get stuck among the incoming people, walk through the congestion, or even unintentionally occupy in a dense area, although more comfortable passageway exists. These odd behaviors are usually produced and simply noticeable in bidirectional case. This paper aims at reducing these artifacts to achieve more behavioral fidelity, by adding the explicit metabolic-energy-minimal short-term path planning (MEM) in between GPP and LCA. For energy analysis, the optimal control theory with the objective energy function from the study of biomechanics was employed, which finally leads to the useful optimal walking characteristics for the pedestrians. The simulation results show that the pedestrians with MEM can adapt their moving to avoid the congestion, resulting in more promising lane changing and overtaking behaviors. Even though MEM was mainly developed to deal with the artifacts in bidirectional flows, it can be extended with a little modification and can produce significant behavioral improvement for multi-directional case as shown in the last part of the paper

Using Multi-Descriptors for Real Time Cosmetic Image Retrieval

Cosmetic Image Retrieval (CIR) is a methodology for searching and retrieving images from Cosmetic Image Collection (CIC). There are numerous cosmetic brands whose types are similar to others. In addition, there are not trivial to retrieve cosmetic images because of its complexity and duplicative shape, as well as detail of various cosmetic items. We present a method for CIR using multi-descriptors, combining global and local features for image descriptors. Along with integrating a Scale-Invariant Feature Transform (SIFT) and Critical Point Filters (CPFs) to achieve accuracy and agility in CIR processing, called CPF level 9 & SIFT. SIFT is used for detailed-image, such as cosmetic image, to reduce the time complexity for extracting keypoints. On the other side, CPF will filter only for the critical pixel of the image. From the experiment, our method can reduce computation time by 50.46% and 99.99% by using SIFT and CPF respectively. Moreover, our method is preserved efficiency, measured by precision and recall of CPF level 9 & SIFT, which is as high as the precision and recall of SIFT

Reviews on Physically Based Controllable Fluid Animation

In computer graphics animation, animation tools are required for fluid-like motions which are controllable by users or animator, since applying the techniques to commercial animations such as advertisement and film. Many developments have been proposed to model controllable fluid simulation with the need in realistic motion, robustness, adaptation, and support more required control model. Physically based models for different states of substances have been applied in general in order to permit animators to almost effortlessly create interesting, realistic, and sensible animation of natural phenomena such as water flow, smoke spread, etc. In this paper, we introduce the methods for simulation based on physical model and the techniques for control the flow of fluid, especially focus on particle based method. We then discuss the existing control methods within three performances; control ability, realism, and computation time. Finally, we give a brief of the current and trend of the research areas

Design and Development of Real-Time Communication Content Management System for E-Commerce

Abstract-E-commerce is very efficient and effective, but it needs programming knowledge to create and manage. Many small organizations do not have human resource for this task and cannot support cost for hiring programmers. Thus, many application providers create content management system applications to enable the e-commerce website to be created and managed through friendly user interface. However, existing content management system applications for e-commerce is lack of real-time communication feature, even it is an important feature for e-commerce. Although e-commerce feature can be manually coded and added, lack of programming knowledge problem occurs. Therefore, this project solve this problem by designing and developing content management system for ecommerce which concentrated on real-time communication feature using instant messaging and short message sending. It covers e-commerce feature and content management system feature. The system is divided into two styles, front office and back office style and seven subsystems. It is developed using HTMP, CSS, and PHP language along with Ajax technique. This system is tested by ten subjects

An Image Matching Using Critical-Point Filters and Level Set Analysis

Critical-Point Filters (CPFs) are nonlinear filters which preserve intensity and location of each critical point in the image and reduce the resolution without any prior knowledge. Although CPFs can avoid blurred intensity and ambiguous location problem of previous linear filters, its computational cost is still expensive due to its complexity. We propose an enhancement of the CPFs algorithm for image matching using level set analysis. An image is analyzed and transformed to hierarchical level sets of pixel having same intensity. Connectivity of the level sets represents the image contrast invariant features. Between the corresponding level sets of the input images, two pixels are mapped based on their energy and bijectivity conditions. Finally, less computational time with precise mapping is shown in the experimental result

3-D Object Extraction Using Volume Computation

This paper describes an alternative approach to extracting 3-D objects and volumes, from lists of given faces, edges, vertices, and the vertices' coordinates. Most graphics file formats store 3-D information for various purposes as a list of polygons, which does not provide a direct indication of structure or relationships between each object. This leads to the limitation of object identification within the list of data. The proposed algorithm was developed as part of a method for finding the Abstract Cellular Complex of an object. The volumes (whether closed or open) of an object are determined from the input set of faces. Each object is then extracted according to its manifold. This algorithm can identify every volume and extract them from the set of given data when the object(s) represented by the data have a genus of 0

Finding Thin Points in an Abstract Cellular Complex

This research describes an algorithm to find “thin points'” in a solid represented as an Abstract Cellular Complex. The algorithm is mostly iterative, adding one face at a time to a set of previously selected faces, and choosing the selections that produce the loops with the shortest lengths for the next iteration. The output from the algorithm is a set of loops that indicate the thinnest portions of the solid. As implemented, the algorithm allows a threshold to be set to limit the number of loops that are selected in each iteration. The results indicate that, while it does occasionally produce errors, the algorithm is mostly accurate, and a lower threshold increases its speed, without negatively affecting its accuracy

Enhanced Billboards for Model Simplification

A set of billboards can represent 3D models for extreme simplification in real-time rendering. Unlike conventional polygon method, billboard-based technique has the rendering time of the model proportional to its contribution to the image. Thus, it has an automatically built-in Level of Detail. However, previous techniques still have limited viewing angle and do not accurately represent the model. We present an adaptive rendering method using enhanced billboards. First, each enhanced billboard, representing portion of the model, is defined to have four maps: depth map, normal map, color map and transparency map. The model is then projected onto a number of viewing planes in different viewing directions. Consequently, these enhanced billboards are rendered based on ray-height-field intersection algorithm implemented on GPU. This representation can maintain the geometry and the silhouette of the model with no limit in viewing direction. Moreover, real-time rendering is supported