## Pre-Revision Hints - Write the pseudocode or steps to find the HOG feature. - What happens if you change the HOG feature from 2x2 to 4x4. ## Exam Info - Don't be misled by previous years. - Previously 2/3, now 4/5. - More questions, same time, less time per question. - Q1 is compulsory. - More options as there is more to cover. - Do one of two coding tasks. - More graphics on 2021/2022 paper than our one. ## Exam hints - Probably won't be asked for algorithms, but could be asked for general steps. - What are steps when detecting faces, steps to follow to compute HOG of descriptor, steps for camera calibration. - Very small computations, like how to compute the gradient for a particular pixel in x direction, y direction, etc. - One could be canvas 2d, one could be threejs, no guarantee that there won't be two on the same technology. - Can't get away with just studying one technology. - Theory questions and application questions. - Doing analysis on an image. - Won't be too theoretical, going into mathematics, will be more applied. - One is around camera calibration and the other around feature and descriptors. - We did basics like calculating differentials. - These will be the ideas around Q4 and Q5. - Won't be calculating eigenvalues. - Basic mathematics. - Compute the total amount of features you have in HOG. - Don't focus on solving mathematics for camera calibration, just need to understand how you create an intrinsic matrix given focal length etc. - Construct K-matrix. - Anatomy of the camera matrix. - What the rows of the P-matrix means. - Feature side: - Focus on steps need to follow, why you need to. - Benefit of principal components. - Just have to do one image analysis question. - Try not to just pick one, the other one could be difficult. - Exam won't be easy. - Make sure you understand concepts covered in class. - Waqar's part is more novel, so he has given us extra info about exam. - Nasre's stuff is more overlapping from previous years. - Will be given useful methods to refer to, like in Sam's papers. - Answer can be derived from methods given. - For both Canvas and ThreeJS. - Definition of surface normal for example, can give formula or describe. - Nasre tends to be more applied: might ask more applied questions that theoretical questions. - Analyse this image, write this code. - Perfect answer for erosion: no equation, description, example. - We didn't do image de-calibration. - Hough transform? - Or adaptive thresholding? - Think in transforms, draw transforms. - Nasre really likes transforms. - It's good to look at previous exam papers. - Possibly taken question from previous years??? - Was answering question. - Look at last 3/4 exam papers. - Wouldn't pass if you only studied last year's paper. - Try to remember kernel matrices for filters, e.g., smoothing etc. - Nasre wants us to know the matrix values. - Can learn how to develop kernel from first principles. - Here is a one directional filter, make a two directional one. - like how you make laplacian of gaussian. - How to convolve filters.