The Effect of Image Resolution on the Performance of a Face Recognition System

In this paper we investigate the effect of image resolution on the error rates of a face verification system. We do not restrict ourselves to the face recognition algorithm only, but we also consider the face registration. In our face recognition system, the face registration is done by finding landmarks in a face image and subsequent alignment based on these landmarks. To investigate the effect of image resolution we performed experiments where we varied the resolution. We investigate the effect of the resolution on the face recognition part, the registration part and the entire system. This research also confirms that accurate registration is of vital importance to the performance of the face recognition algorithm. The results of our face recognition system are optimal on face images with a resolution of 32 times 32 pixels

I. Introduction

In video surveillance applications it is often difficult to obtain good quality recordings of the faces of the observed individuals. One important factor determining the quality of the recordings is the resolution of the images, which is often much lower than the resolutions typically used in face recognition. Therefore, we decided to investigate the lowest resolution at which a face recognition system still can achieve acceptable performance. In a face recognition system several processing steps are needed to recognize a person's face. Here, we investigate the sensitivity of the recognition part and the registration part to the image resolution.