WHAT IS COMPUTER VISION? Provides computers with the ability to see and understand images. Has an anonymous impact on industries like automotive, manufacturing, etc. R evolutionizing the hiring process.
APPLICATIONS Sifting videos Detection of metal and other structures in electric towers(divide into the grid) Rust detection Rusted areas of the bridge Damage detection
RESEARCH IN COMPUTER VISION Detection of objects Detecting objects in self-driving cars Image-to-image translation(winter to summer)/(zebra to horse) Dance pose detection
WEEK 2
What is a digital image? A digital image can be interpreted as a rectangular array of a number The image is comprised of rectangular blocks called pixels Pixels can be represented as numbers called intensity values PIL import image module Show-plot image or matplotlib.imshow Attribute size is the no of pixels that make height and width Attribute mode color space
Manipulating Images Id function is used to find the object memory address Flipping images changes the images orientation Changing the index value of the image flip the image PIL images are flipped by using (flip, mirror, and transpose) Openvc images are flipped by using (flip , rotate) Cropping is cutting out the part of image and throwing out the rest PIL Imagedraw function to draw PIL image object I mageFont module for fonts
Pixels Transformations A histogram counts the no of occurrences of a pixel It understands and manipulates images Intensity transformation changes a image one pixel at a time S=2r+1 Alpha-contrast control Beta-brightness control convertscaleAbs is used instead of array operations after applying transformations Histogram equalization—an algorithm that uses image histogram to adjust contrast
Spatial operation in image processing Convolution or linear filtering is a standard way to Filter an image the filter is called the kernel Z= wx (x is input image,w = kernel filter)
IMAGE CLASSIFICATION Image classification is the process of taking an image or picture and getting a computer to automatically classify it, or try to provide the probability of the class of the image. A large portion of data is used for training and a smaller for testing K nearest neighbour ( knn ) is slow. The use of all the samples in the dataset is called an epoch When we use all samples it is called batch gradient descent where one iteration equals one epoch
Methods of object detection Sliding windows detection- ----we start from one region and classify that sub-image---we then shift th e window and classify the next sub-image—repeat Bounding boxes----- rectangular box An adaboost classifier is used to reduce the no. of features Strong classifier is the combination of weak classifiers