Constant colour matting with foreground estimation

Constant colour matting consists of estimating for each pixel of an image the propor- tion α of an unknown foreground colour with a known constant background colour. The α-matte is then used to replace this background with another image. Existing approaches approximate α directly but post-processing is required to remove spill of the background colour in semi-transparent areas. Instead of estimating α directly, we propose 3 methods to estimate the unknown foreground colour, and then to deduce α. This approach leads to high quality mattes for transparent objects and allows spill-free results (see www.cs.nuim.ie/research/vision/data/imvip2014/). We show this through an evaluation of the proposed methods based on a ground truth dataset.

Constant colour matting with foreground estimation from Guillaume Gales