Automatic video matting through scribble propagation

Abstract

Video matting is an extension of image matting and is used to extract the foreground matte from an arbitrary background of every frame in a video sequence. An automatic scribbling approach based on the relative motion of the foreground object with respect to the background in a video is introduced for video matting. The proposed scribble propagation and the subsequent isolation of foreground and background is much more intuitive than the conventional trimap propagation approach used for video matting. Alpha maps are propagated according to the optical flow estimated from the consecutive frames to get a preliminary estimate of the foreground and background in the following frame. Accurate scribbles are placed near the boundary of the foreground region for refining the scribbled image with the help of morphological operations. We show that a high quality matte of foreground object can be obtained using a state-of-the-art image matting technique. We show that the results obtained using the proposed method are accurate and comparable with that of other state-of-the-art video matting techniques.