Facial expressions convey non verbal cues, which play an important role in interpersonal relations. Automatic recognition of human face based on facial expression can be important component of natural human-machine interface. It may also be used in behavioral science. Although human can recognize the face practically without any effort, but reliable face recognition by machine is a challenge. This book presents a new approach for recognizing the face of a person considering the expression of the same human face at different instant of time. This methodology is developed combining Eigenface method for feature extraction and k-Means clustering for identification of the human face. In experimental purpose, AT&T face database is used which contains a set of 40 people with 10 images with different facial expressions at the different illumination. Experimental results demonstrate the efficacy of the approach. This book is written such a manner that it will help researchers to work on... Это и многое другое вы найдете в книге An Efficient Human Face Recognition Approach (Soumen Bag)