4. Machine Vision / Computer Vision / Image Understanding / Photogrammetry Trying to make Computers extract some useful information from images… Recognize faces, finger prints, other biometrics… Detect anamolies in X-Rays, Ultrasounds, … Point out suspicious human activity like fighting (surveillance) Use ‚vision‘ as a sensor in Control Systems… Make truly ‚autonomous‘ and ‚mobile‘ robots possible… Sophisticated special effects in movies… New and friendlier interfaces to Computers and other machines…
54. Clustering of pixels in image Make one vector per pixel of the image, X i = [x, y, R, G, B] Apply clustering on these vectors…call all pixels that end up in the same cluster as one segment! WHY ?
55. K-Means Clustering Algorithm Step 1: Determine number of clusters K Step 2: Randomly choose K different mean vectors: m 1 , m 2 , …, m K Step 3: Choose a data vector X i, and calculate Euclidean distance between this vector and all the mean vectors one-by-one. Step 4: Assign this data vector to the cluster with the minimum distance Step 5: Set i to i + 1, and go back to step 3 Step 6: Calculate new mean vectors based on assignments Step 7: Set i = 0, and go back to step 3
67. Project 4: Object Recognition Challenges 7: Intra-class variation My PhD focus is intra-class and viewpoint invariance – alongwith all the other problems..