Facial expression, a significant way of nonverbal communication, effectively conveys humans' mental state, emotions and intentions. Understanding of emotions through these expressions is an easy task for human beings. However, when it comes to Human Computer Interface (HCI), it is a developing research field that enables humans' to interact with computers through touch, voice, and gestures. Communication through expression in HCI is still a challenge. In addition, there are a variety of fields such as automotive, biometric, surveillance, teleconferencing etc. in which expression recognition system can be applied. In recent years, several different approaches have been proposed fr facial expression recognition, but most of them work only under definite environmental conditions.
The proposed framework aims to recognize expressions (by analyzing the facial features extracted) based on the Active Shape Model (ASM). Four different expressions namely happy, disgust, surprise and neutral are handled in our approach. The proposed system first identifies the face region from the input image. Thereafter, a model based approach called ASM is applied to identify the major landmarks on the face that has been detected. Based on the position of these landmarks, expression of the detected face is identified.
The recognition of expression is beneficial in multiple ways. Firstly, the expressions captured along with additional features which are used in existing systems such as gaze direction, speed of eye blinking, rotation of the head etc are useful inputs towards building safety systems for the vehicle. Such a system would use these inputs and generate appropriate warnings to the driver as and when necessary. Secondly, the expression recognition will serve the purpose of providing a customized entertainment unit that can adapt itself based on the mood of the driver. For e.g. there is a possibility to change the song that played by music system in the vehicle. If the expression of the driver is detected as happy, the music player can play a happy song.