Methods of image transformation for person authentication using face thermographic image

Abstract

The purpose of the paper is to study the holistic image transformation methods for person's identity authentication from a thermographic image of faces. Within this study the datasets of images of faces in the far infrared range (LWIR) have been collected. The novelty of the study consists in the features of the dataset of images which collected in real conditions that affect the quality of authentication, such as facial expressions, wearing glasses or a medical mask, applying makeup / cosmetics, different illumination and temperature conditions of the environment, head turns. The methods under the study are based on the construction and selection of image features while reducing the dimension and converting the image into another form of representation. These methods are used to solve the problem of distinguishing features in images, in authentication person identity by 2D image of his face and allows solving other computer vision problems. This paper discusses classical methods of integral image transformation: principal component analysis, principal component analysis using a kernel, linear descriptor analysis, independent component analysis, truncated singular value decomposition, discrete cosine transformation. As a measure of the proximity of images, the Euclidean distance between the vectors of image features is used. Testing of the methods was performed on a set of thermograms consisting of 632 thousand images of the faces of 158 people. The F-measure was used as a metric to assess the quality of comparison of the selected methods. As a result of the experiment, the independent component analysis method showed the highest values of the F-measure metric – 0.72. The results of the study can find applications in access control and control systems to increase the fault tolerance of authentication of persons. The use of the considered methods is effective in the tasks of processing thermographic images for authenticating a person by secondary signs, by the pattern of his veins and vessels on the face, in cases of changes in facial expressions and appearance by means of applying makeup and wearable accessories.

Keywords

• computer vision, authentication algorithm, face thermogram, holistic transformation methods, principal component analysis, linear descriptor analysis, independent component analysis, truncated singular value decomposition, discrete cosine transformation.