Facial expression recognition (FER) plays a vital role in the automatic detection of human emotions with intelligent machine. Since the FER is an interdisciplinary technique involving biology, computer science and even psychology, more challenges will be encountered as we pursue a high recognition accuracy of facial expressions. Inspired by the progressive enhancing procedure of face recognition of human, we proposed a multiple impression feedback recognition model (MIFR) for the identification of facial expression. Different from current deep learning techniques, the MIFR realizes a quick facial expression recognition through cascade feedback recognition cycles. Multiple impression features of an FER image are firstly obtained by the discrete wavelet decomposition (DWT). Each recognition cycle is implemented by inputting wavelet impression features in a specific decomposition scale into a classifier set of parallel Support Vector Machines (SVMs). In terms of coarse-to-fine wavelet features on multiple scales, the recognition results are gradually improved through integrating classification probability vectors of multiple cycles. In order to validate the performance of the MIFR_SVM for face expression recognition, we also conducted an experiment of facial multi-view expression with occlusion (FMEO) in the laboratory. Three traditional schemes and seven deep learning schemes have been chosen for the FER comparison of three public datasets and one lab dataset FMEO. The classification results show that the MIFR_SVM is not only superior than traditional schemes, but also performs better than deep learning techniques, including both neural-network-based ones and random-forest-based ones. The average recognition accuracy of MIFR_SVM reaches to 92.31% for four datasets. Furthermore, the MIFR_SVM has fewer parameters, less complexity and adaptable cascade structure, which is more suitable for the image datasets with small size or with diverse qualities.
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