Automatic Brightness Control for Face Analysis in Near-Infrared Spectrum

Face analysis is a broad and well-established research area whose main focus is put on face detection, segmentation, recognition and facial features extraction. A crucial prerequisite to face analysis algorithms properly work is to have an input image of high quality with similar properties in different conditions. For this reason, near-infrared images are used due to being more robust to change in lighting conditions and time of day than the visible light spectrum images. Automatic brightness control is used to properly adjust scene brightness to extract useful information. A novel algorithm implementation for the automatic brightness control is proposed based on a split range feedback controller with a camera occlusion detection included. The proposed algorithm is accurate, fast and suitable for real-time embedded system implementation.