The problem with this approach for image morphing is it makes it difficult to author morphs. A better way is to select features on both images that correspond to one another. The seminal paper on this technique (used by Michael Jackson's "Black & White" video AFAIK) is from 1992:<p><a href="http://www.cs.princeton.edu/courses/archive/fall00/cs426/papers/beier92.pdf" rel="nofollow">http://www.cs.princeton.edu/courses/archive/fall00/cs426/pap...</a>