Most still cameras and video cameras have a finite ability to resolve small differences in light intensity and to measure this intensity accurately. The use of such systems to image scenes with high dynamic range may result in underexposed or overexposed regions of interest in the captured video and/or still images. This technology describes a system for the accurate imaging of scenes with large variations in brightness. This technology takes advantage of image processing and analysis methods to adaptively adjust its exposure settings based upon the brightness of objects of interest. This technology can also accurately image moving objects with large brightness variations by tracking them with optical flow techniques.
Conventional, automatic gain control techniques based upon average scene brightness may not adequately compensate for brightness variations in different regions of the scene. To address this problem, this technology processes acquired images to identify and determine the brightness of objects of interest within a scene. The imager’s exposure settings are adaptively adjusted to accommodate the measured object’s brightness in subsequent imaging operations. To accurately image moving objects and changing scenes, this technology can employ optical flow methods to track objects of interest or update only those pixels whose brightness values are within the preferred range of the imager during each image acquisition. Multiple imagers may also be used to image all segments of an entire scene.
The technology’s imaging accuracy was demonstrated with static and video scenes.
Patent Issued (US 7,495,699)
Tech Ventures Reference: IR M02-051