The Hong Kong Polytechnic University (PolyU) NIR Face Database


The Biometric Research Centre (UGC/CRC) at The Hong Kong Polytechnic University has developed a real time NIR face capture device (show in Figure 1), and has used it to construct a large-scale NIR face database. To advance research and to provide researchers working in the area of face recognition with an opportunity to compare the effectiveness of face recognition algorithms, we intend to publish our NIR face database, making it freely available for academic, noncommercial uses.

The hardware of our NIR face image acquisition system consists of a camera, an LED (light emitting diode) light source, a filter, a frame grabber card and a computer. A snapshot of the constructed imaging system is shown in Fig. 1. The camera used is a JAI camera, which is sensitive to NIR band. The active light source is in the NIR spectrum between 780nm - 1,100 nm and it is mounted on the camera. The peak wavelength is 850nm, and it lies in the invisible and reflective light range of the electromagnetic spectrum. An NIR LED array is used as the active radiation sources, and it is strong enough for indoor use. The LEDs are arranged in a circle and they are mounted on the camera to make the illumination on the face is as homogeneous as possible. The strength of the total LED lighting is adjusted to ensure a good quality of the NIR face images when the camera face distance is between 80cm-120cm, which is convenient for the users. When mounted on the camera, the LEDs are approximately coaxial to the imaging direction and thus provide the best possible straight frontal lighting. Although NIR is invisible to the naked eyes, many CCD cameras have sufficient response to the NIR spectrum. The filter we used in the device is used to cut off the visible light, whose spectrum is shorter (780nm, visible light). For the convenience of data collection, we put the imaging device into a black box of 19cm width, 19cm long, and 20cm high, as shown in Figure 1.


Fig. 1: The NIR face image acquisition device. ‘A’ is the NIR LED light source, and ‘B’ is the NIR sensitive camera with an NIR filter.


By using the self-designed data acquisition device described above, we collected NIR face images from 335 subjects (Due to some missing data, here we only release 335 subjects instead of 350 referred in our paper). During the recording, the subject was first asked to sit in front of the camera, and the normal frontal face images of him/her were collected. Then the subject was asked to make expression and pose changes and the corresponding images were collected. To collect face images with scale variations, we asked the subjects to move near to or away from the camera in a certain range. At last, to collect face images with time variations, samples from 15 subjects were collected at two different times with an interval of more than two months. In each recording, we collected about 100 images from each subject, and in total about 34,000 images were collected in the PolyU-NIRFD database. The sample images in the PolyU-NIRFD are labeled as ‘NN_xxxxxx_S_D_****’, where “NN” represents the prefix of the label string, ‘S’ represents the Gender information, ‘xxxxxx’ indicates the ID serial number of the subject, ‘D’ denotes the place where the image was captured, and ‘****’ is the index of the face image. For example, “NN_200001_F_B_024” means that the 24th image is from a Female subject collected in Beihang University. Fig. 2 shows some face images of a subject with variations of expression, pose and scale. Fig. 3 shows the images of some subjects which were taken in different times.

Fig. 2: Sample NIR face images of a subject. (a) Normal face image; and images with (b) expression variation; (c) pose variation and (d) scaling variation.

Fig. 3: Sample NIR face images captured in more than two months.

Related Publication:

1.    Baochang Zhang, Lei Zhang, David Zhang, and Linlin Shen, “Directional Binary Code with Application to PolyU Near-Infrared Face Database”, Pattern Recognition Letters, vol. 31, issue 14, pp. 2337-2344, Oct. 2010. 

The Announcement of the Copyright

All rights of the PolyU-NIRFD are reserved. The database is only available for research and noncommercial purposes. Commercial distribution or any act related to commercial use of this database is strictly prohibited. A clear acknowledgement should be made for any public work based on the PolyU-NIRFD. A citation to “PolyU-NIRFD,” and our related works must be added in the references. A soft copy of any released or public documents that use the PolyU-NIRFD must be forwarded to:


Downloading Steps (Recommend to open by IE):

This PolyU NIR Face Database (Due to the large size of data, we have divided it into 6 parts), is made publicly available and can be obtained from this website. It is totally free for academic, noncommercial purposes. Here, we also provide the training, gallery, probe subsets which are used in our paper “Directional Binary Code with Application to PolyU Near-Infrared Face Database” (including the Experiment 1,2,3) for reference and comparison. Any person or organization that wishes to use the database must agree to the terms of the agreement and fill in the agreement forms. The successful applicants will receive their login accounts and passwords to download the database.



Copyright © 2013   Biometric Research Center, The Hong Kong Polytechnic University