Key extraction by image differentiation
Tomoo Mitsunaga, T. Yokoyama, Takashi Totsuka · Proceedings - International Conference on Image Processing · 2002
Key extraction is an inverse problem of finding the foreground, the background, and the alpha value from an image and some hints. Although the chromakey solves this for a limited case (single background color), this is often too restrictive in practical situations. When the extraction from an arbitrary background is necessary this is currently done by a time consuming manual task. To solve the problem, an algorithm must address the unique requirements of the key extraction: high resolution, analytically correct alpha values, and easy human interaction. We present an image differentiation method which, for the first time, fulfills these requirements.