Cuilan Wang

Synthesis of 3D Model of a Magnetic Field-Influenced Body from a Single Image

A method for recovery of a 3D model of a planet-sized cloud-like structure that is in motion and deforming but approximately governed by magnetic field properties is described. The method allows recovery of the model from a single intensity image in which the structures silhouette can be observed. The method exploits envelope theory and a magnetic field model. Given one intensity image and the segmented silhouette in the image, the method proceeds without human intervention to produce the 3D model. In addition to allowing 3D model synthesis, the methods capability to yield a very compact description offers further utility. Application of the method to real-world data is also demonstrated.

New hypothesis distinctiveness measure for better ellipse extraction

A new method for determination of the best hypothesis in Hough transform (HT)-based methods to detect ellipses is described. The method uses a new distinctiveness measurement to rank the hypotheses and determine a suitable candidate. The method is aimed at improving HT robustness to image noise and quantization effects. Experiments on images that demonstrate the methods applicability are also presented.

On accuracy of marching isosurfacing methods

Representational accuracy of the isosurface meshes produced by well-known marching isosurfacing methods is considered. Accuracy is determined versus the isosurface given by trilinear interpolation and quantified using a new measure of volumetric divergence. The new measure is an accurate estimate of spatial discrepancy between a produced mesh and the isosurface of trilinear interpolation. Through experimental testing using the measure, suitability of the considered methods to well-model the isosurface of trilinear interpolations behavior on grid cell interiors is also established.

Evaluation of high order approximating normals for Marching Cubes

Two new approaches for approximating normals for volume visualization by marching cubes isosurfacing are introduced. The approaches utilize higher order approximations than the standard approach of simple central differencing gradients. The impact of the new approximation approaches on isosurface renderings are also considered by quantitative pixel-level comparisons on scenes for which optimal renderings are known.