Image Warping and Mosaicing
By Ruochen(Chloe) Liu
Overview
In this assignment I tried image mosaicing. Basically I take several photos and create an image mosaic by registering, projective warping, resampling, and compositing them. Along the way, I have to compute homographies and use them to warp images.
Shoot the Pictures
The first step is to shoot three pictures from the same point of view but with different view directions.
middle
left
right
Recover Homographies
In this part I recover the parameters of the transformation between each pair of images. In our case, the transformation is a homography: p’=Hp, where H is a 3x3 matrix with 8 degrees of freedom (lower right corner is a scaling factor and can be set to 1). Then I transformed it into a least square problem Ax=b and we want to solve for x.Below are the screenshots of the homographies I found for the left and right images respectively.
left homography
right homography
Warp the Images
In this part I warp the images using the homographies I just calculated. Below are the warped images.
warped left
warped right
Image Rectification
In this part I picked some random images and “rectify” them, which means I warp them so that the planar surfaces are frontal-parallel.
original