It is true that Eigenfaces and, more generally, appearance-based approaches are holistic. Nonetheless, eigenfaces and other appearance-based approaches have been used in local face patches. The information extracted from each patch is then combined using some multi-classifier approach. The authors may want to include a short paragraph describing these alternate algorithms. This could be included where the authors describe the idea of “eigeneyes.”
“faces images” should be “face images”
In “However, the method is sensitive to variation in lighting, scale, and pose” you may want to add that the method is also sensitive to “expression changes” and “occlusions.”
We thank this reviewer for his helpful and constructive comments. We have made revision accordingly.