Security identification system
View Patent ↗This is a security and identification system designed to obtain improved images for use by real-time facial recognition and identification systems for screening individuals passing through secure entry or checkpoints such as airport passenger terminals, government offices, and other secure locations. The system detects the presence of a subject at the checkpoint, interactively instructs the subject to stop and move into position for proper identification and recognition, analyzes the facial features of the subject as (s)he passes through the checkpoint, and compares the features of the subject with those in a database. The system then generates different signals depending upon whether or not the subject is recognized. In one aspect of the invention, different methods and apparatus are provided for compensating for low ambient light so as to improve the quality of the facial image of the subject that is obtained.
1. A method of capturing images of a subject at a checkpoint for recognition of the subject comprising the steps of:
creating a checkpoint;
positioning an image capturing device so that the image capturing device can capture an image of a subject at the checkpoint;
filtering the light that enters the image capturing device so that only a predetermined bandwidth enters the image capturing device;
positioning a light source so that the light source can illuminate a subject at the checkpoint;
providing a light from the light source when the light source is activated that has a bandwidth that is similar to the predetermined bandwidth that enters the image capturing device;
capturing a first image of a subject at the checkpoint with the image capturing device with ambient light;
activating the light source;
capturing a second image of the subject at the checkpoint with the image capturing device while the light source is activated; and
determining a difference image by subtracting the second image from the first image.
2. A method as recited in claim 1 wherein said filtering step comprises filtering the light that enters the image capturing device so that the light that enters the image capturing device is in the range of approximately 800 nanometers to approximately 1100 nanometers.
3. A method as recited in claim 2 wherein said filtering step comprises filtering the light that enters the image capturing device so that the light that enters the image capturing device is in the range of approximately 820 nanometers to approximately 880 nanometers.
4. A method as recited in claim 3 wherein said filtering step comprises filtering the light that enters the image capturing device so that the light that enters the image capturing device is in the range of approximately 830 nanometers to approximately 870 nanometers.
5. A method as recited in claim 2 wherein said filtering step comprises filtering the light that enters the image capturing device so that the light that enters the image capturing device is in the range of approximately 850 nanometers to approximately 910 nanometers.
6. A method as recited in claim 5 wherein said filtering step comprises filtering the light thai enters the image capturing device so that the light that enters the image capturing device is in the range of approximately 860 nanometers to approximately 900 nanometers.
7. A method as recited in claim 1 further comprising the step of checking the saturation level of the difference image to determine if the difference image is within a predetermined range of saturation.
8. A method as recited in claim 2 further comprising the step of checking the saturation level of the difference image to determine if the difference image is within a predetermined range of saturation.