Estimating the Smile by Evaluating the Spread of Lips

Abstract

Smile is one of the important emotions that is essential in computer vision tasks. The greatly influenced part due to it is the lips. By encountering the changes in lips of smile images with respect to no smile, a smile detecting model can design for the computer vision tasks. In this paper, the approach is to evaluate the spread of lips. The lips movement distance is evaluated with respect to the eyes. 68 landmark points of dlib are used for this purpose. The left and right corners of lips are evaluated with the left and right eyes respectively using the count of landmark points (l and r). The secondary parameters - average, Maximum, and maxavgsum of l and r are used for evaluating the lip expansion variation. For each value of these parameters that can attain from l and r, the count of no smile images below it and count of smile images above it is considered and calculated the attainable efficiency. The value of secondary parameter having the maximum efficiency is defined as the threshold. The maximum efficiency that is attained due to average, Maximum and maxavgsum are 80.06, 67.3 and 78.54 respectively at the thresholds 2, 3 and 4.5 respectively.