Chroma keying based on stereo images

摘要

Alpha matting is known as a process of accurately separating a foreground object from an image and it has been extensively studied in both academic and industrial areas as an important part of multimedia technology. However, most existing methods utilize single image to get its alpha matte. In this paper, we propose a novel chroma keying method based on stereo images, which can be applied to post-process the alpha matte generated by any matting approach. Given a pair of stereo images, a new matting Laplacian matrix is constructed based on the affinities between matching pixels and their neighbors from two frames. Based on the new matting Laplacian matrix, a new cost function is also formulated to estimate alpha values of the reference image through the propagation between stereo images. The experimental results illustrate that this method can be applied to different categories of existing alpha matting approaches and can obtain alpha matte of higher quality.