1. A method comprising: receiving an indication of a brush stroke made on an image displayed in a user interface, wherein the user interface provides a plurality of brush types, including a first brush type for identifying a foreground region of the image and a second brush type for identifying an unknown region of the image; identifying an area of the image as a foreground region based at least in part on a location of a brush stroke of the first brush type on the image; generating a boundary area on a border of the foreground region, the boundary area containing an unknown region; identifying the unknown region of the image based at least in part on a location of a brush stroke of the second brush type on the image; solving, by a processor, the unknown region to provide an alpha matte that distinguishes a foreground portion from a background portion in the unknown region; and displaying the alpha matte for the unknown region in real time in response to receiving the indication of a brush stroke of a one of the plurality of brush types.