Subtle expression recognition based on hybrid features and classifier tree
Zhou Geng-tao · Jisuanji gongcheng yu sheji · 2008
Most of facial expression recognition researches are focused on six basic facial expressions currently,and subtle facial ex-pressions recognition has not been considered.A method of subtle expression recognition based on hybrid features and classifier tree is presented in this paper.Texture feature for the eye area is extracted by using Gabor wavelet transformation,texture feature for the nose area is extracted by using 2D-DCT,and shape variety feature for the mouth area is extracted by using AAM.At the recognition stage,the expressions are classified roughly by subsuming confusable expressions in the same kind of expression firstly.Then the expression features that contribute much to this kind expression are selected for fine classification.In the process of each grade classification,discrete HMM is adopted for expression recognition in each expression area respectively.The classification results are fused by means of integ-rating the probability of each expression in each area with its weight obtained during the training phase.Experiments show that this method can get high recognition rate.And it also has high speed and is suitable for real time subtle expression recognition.