Eliciting qualitative structure from image curve deformations
نویسندگان
چکیده
A family of qualitative methods is described that determine structure of curves in a scene from their image projections in two or more views. For example, plane curves are distinguished from space curves, and space curves from contour generators. The novelty of the approach is: rst, it is unaaected by camera intrinsic parameters, so calibration is not required; second, is it also unaaected by camera motion (extrinsic parameters) so viewer motion (or epipolar geometry for stereo) need not be known; and third, curves need not be matched point by point. The method involves recovering structure modulo a 3D aane or projective transformation. Tests on this relative structure classify the curve into its qualitative type. The practical power of this family of methods is demonstrated using a real-time vision system based on B-spline snake-tracking.
منابع مشابه
Comparative Analysis of Quasi-Conformal Deformations in Shape Space
A novel approach based on the shape space concept is proposed to classify quasi-conformal deformations of 3D models. A new metric on the quotient space of meshes is introduced to capture changes of the curvature at each vertex of a simplicial complex during deformation. Then, the deformation curve is obtained by calculating the geodesic curve connecting two shapes in the shape space manifold. I...
متن کاملMapping Local Image Deformations into Depth
The paper presents a 2 frame structure-from-motion algorithm that operates by mapping local changes (image deformations) into estimates of time-to-collision (TTC). For constant velocity motion of the camera in a stationary scene, time-to-collision amounts to coarse depth data useful for navigation and qualitative scene understanding. The theory is supported by a set of experiments demonstrating...
متن کاملAnalysis of Rotational Deformations from Directional Data
This paper discusses a novel framework to analyze rotational deformations of real 3D objects. The rotational deformations such as twisting or bending have been observed as the major variation in some medical applications, where the features of the deformed 3D objects are directional data. We propose modeling and estimation of the global deformations in terms of generalized rotations of directio...
متن کامل3D Interactive Ultrasound Image Deformation for Realistic Prostate Biopsy Simulation
Realistic medical procedure simulators improve the learning curve of the clinicians if they can reproduce real conditions and use. This paper describes the improvement of a transrectal ultrasound guided prostate biopsy simulator by adding the simulation of real-time prostate movements and deformations. A discrete bio-mechanical model is used to modify a 3D texture of an ultrasound image volume ...
متن کاملSketch-based aesthetic product form exploration from existing images using piecewise clothoid curves
We present a new sketch-based product form exploration technique that works from images and sketches of existing products. At the heart of our approach, is a multi-stroke curve beautification method and a curve-based image deformation algorithm. The proposed approach converts groups of strokes into piecewise clothoid curves in order to produce visually pleasing shapes. The deformation diffusion...
متن کامل