1. Software systems for Computer Vision and Image Processing Sungsoo Ha Prof. Murali Subbarao (Stony Brook University) Prof. A.N. Rajagopalan (Indian Institute of Technology, Madras, India) Arnav V. Bhavsar (PhD student, Indian Institute of Technology, Madras, India)

2. Contents Machine (or Computer) Vision System Image Processing Early Vision Process – Edge detection (the Canny Edge detection) Intermediate Vision Process – Hough Transform High Vision Process – Computed Tomography (Filtered backprojection algorithm)

3. Machine Vision System Image Processing Early Vision Process Intermediate Vision Process High Vision Process

4. Image Processing Enhancing Image ContrastReducing NoiseSmoothing Edge detectionArbitrary FilterLinear filter: Convolution

5. The Canny Edge Detector Edge in an image – Significant local changes in an image – Important features for analyzing image Canny Edge Detector – The optimal edge detector – Low error rate – Well localized edge points – Only one response to a single edge

6. Cont’d (Canny Edge detector) Algorithm 1.Filtering: Smooth the image 2.Enhancement: Compute the gradient magnitude and orientation 3.Detection: Apply non-maxima suppression 4.Localization: Use double thresholding

7. Hough Transform (HT) for line detection What is difference with edge detector? Application: geometric pattern matching 1.An image of a single object 2.Decomposed into lines, curves, or other shapes 3.Matched with those in the desired object

8. Computed Tomography (CT) CT : the cross-sectional imaging of an object from its projection data Parallel beam projection Filtered back- projection algorithm

9. 3D Volume Rendering & Graphic User Interface (GUI) System & Software Requirement – OpenGL extension version (2.0) – Cg toolkit (the latest version) – GeForce 8000 series (at least)

10. Conclusion Summarize – Realize very basic and simple applications – Help to understand overall of machine vision system Future work – Improving Hough Transform to detect arbitrary curves – Medical Image Processing Two-level volume rendering SPECT and PET statistical image reconstruction