When presented with an image with similar colors such as the greens in a landscape photo, those programs tend to fail, Adobe says. Similar applications also use a very narrow set of data points to train the software, the researchers say, which makes the system biased to only certain types of images.
Adobe’s latest method, however, relies on the structure of the objects in the photograph, not the colors. The program requires the image and a trimap, or a rough sketch of what should be cut from the image that labels the foreground, the background, and a range in between to enable the computer to find the edges.
The program works by learning the structure of alpha mattes, or the “color” channel that contains all the transparencies in an image. By recognizing the structure instead of separating by color, the program has achieved accurate results even in images with similar tones.
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