After reading about the basics of image processing and manipulation in the previous chapter, we will take a look at some of the most widely used algorithms used to extract meaningful information from the images in the form of edges, lines, circles, ellipses, blobs or contours, user defined shapes, and corners. In context of computer vision and image processing, such information is often termed as features. In this chapter, we will take a look at the various feature detection algorithms, such as Edge and Corner detection algorithms, Hough transformations, and Contour detection algorithms and their implementations on an Android platform using OpenCV.

To make our lives simpler, and have a clear understanding of this chapter, we will first create a basic Android application to which we will keep adding implementations of different feature detection algorithms. This will reduce the amount of extra code that we would otherwise have to write for each...