ofxCorrectPerspective is an OpenFrameworks add-on that performs automatic 2d rectification of images. It’s based on work done in “Shape from Angle Regularity” by Zaheer et al., ECCV 2012. Unlike previous methods of perspective correction, it does not require any user input (provided the image has EXIF data). Instead, it relies on the geometric constraint of ‘angle regularity’ where we leverage the fact that man-made designs are dominated by the 90 degree angle. It solves for the camera tilt and pan that maximizes the number of right angles, resulting in the fronto-parallel view of the most dominant plane in the image.
Capstone Project for Interactive Art & Computational Design (Prof. Golan Levin, Spring 2014)
2d image rectification involves finding the homography that maps the current view of an image to its fronto-parallel view. It is usually required as an intermediate step for a number of applications- for example, to create disparity maps for stereo camera images, or to make projections over planes non-orthogonal to the projector. Current techniques of image 2d rectification require the user to either manually input corresponding points between stereo images, or adjust tilt and pan until a desired image is obtained. ofxCorrectPerspective aims to change all this.