Comparison of Visible, Thermal Infra-Red and Range Images for Face Recognition

Existing literature compares various biometric modalities of the face for human identification. The common criterion used for comparison is the recognition rate of different face modalities using the same recognition algorithms. Such comparisons are not completely unbiased as the same recognition algorithm or features may not be suitable for every modality of the face. Moreover, an important aspect which is overlooked in these comparisons is the amount of variation present in each modality which will ultimately effect the database size each modality can handle. This paper presents such a comparison between the most common biometric modalities of the face namely visible, thermal infrared and range images. Experiments are performed on the Equinox and the FRGC databases with results indicating that visible images capture more interpersonal variations of the human face compared to thermal IR and range images. We conclude that under controlled conditions, visible face images have a greater potential of accommodating large databases compared to long-wave IR and range images.