Research Activities at Florida State Vision Group Xiuwen Liu Florida State Vision Group Department of Computer Science Florida State University http://fsvision.cs.fsu.edu Introduction An image patch represented by hexadecimals Introduction - continued Fundamental problem in computer vision • Given a matrix of numbers representing an image, or a sequence of images, how to generate a perceptually meaningful description of the matrix? – An image can be a color image, gray level image, or other format such as remote sensing images – A two-dimensional matrix represents a signal image – A three-dimensional matrix represents a sequence of images A video sequence is a 3-D matrix A movie is also a 3-D matrix Introduction - continued Why do we want to work on this problem? • It is very interesting theoretically – It involves many disciplines to develop a computational model for the problem • It has many practical applications – Internet applications – Movie-making applications – Military applications Introduction - continued How can we characterize all these images perceptually? Face Recognition Given some examples of faces, identify a person under different pose, lighting, and expression conditions Face Recognition – continued Faces of the same person under slightly different conditions Affective Computing Face Detection Find all faces in a given picture • Typical faces are available Appearance-based Object Recognition Appearance-based object recognition • Recognize objects based on their appearance in images Columbia object image library • It consists of 7,200 images of 100 objects • Each object has 72 images from different views COIL Dataset 3D Recognition Results Appearance-based 3D object Recognition • We compare our result with SVM and SNoW methods reported by Yang et al. (Yang et al., 2000) Methods/Training/test views 36/36 18/54 8/64 4/68 Our method 0.08% 0.67% 4.67% 10.71% Our method without background 0.00% 0.13% 1.89% 7.96% SNoW (Yang et al.,2000) 4.19% 7.69% 14.87% 18.54% Linear SVM (Yang et al.,2000) 3.97% 8.70% 15.20% 21.50% Nearest Neighbor(Yang et al.,2000) 1.50% 12.46% 20.52% 25.37% Object Extraction from Remote Sensing Images An image of Washington, D.C. area Object Extraction from Remote Sensing Images Extracted hydrographic regions Medical Image Analysis Medical image analysis • Spectral histogram can also be used to characterize different types of tissues in medical images • Can be used for automated medical image analysis Video Sequence Analysis Motion analysis based on correspondence Video sequence Analytical Probability Models for Spectral Representation Transported generator model (Grenander and Srivastava, 2000) where • • • • gi’s are selected randomly from some generator space G the weigths ai’s are i.i.d. standard normal the scales ri’s are i.i.d. uniform on the interval [0,L] the locations zi’s as samples from a 2D homogenous Poisson process, with a uniform intensity l, and • the parameters are assumed to be independent of each other Analytical Probability Models - continued Define Model u by a scaled -density Analytical Probability Models - continued Analytical Probability Models - continued Analytical Probability Models - continued 3D Model-Based Recognition Summary Florida State Vision group offers many interesting research topics/projects • Efficient represent for generic images • Computational models for object recognition and image classification • Motion/video sequence analysis and modeling • They can have significant commercial potentials • They are challenging • They are interesting Contact Information • • • • • • Web site at http://fsvision.fsu.edu http://www.cs.fsu.edu/~liux Email at liux@cs.fsu.edu Office at MCH 102D Office hours Mondays and Wednesdays 3:30-5:30PM Phone 644-0050 Courses CAP5615 – Fall 2001 CAP5630 – Spring 2001