A reconfigurable CMOS pixel for applying tone mapping on high dynamic range images

This paper presents the theoretical foundations and the design of a re-configurable pixel circuit capable of capturing images with a wide dynamic range (WDR) of intensities and presenting it in a format fit to be directly displayed on conventional media with limited ability to display WDR scenes. This pixel provides for a programmable transduction function which enables it to produce any monotonically increasing response. Using this flexibility, intensity compression using tone mapping (TM) can be obtained to directly display scenes for wide dynamic range of intensities on low dynamic range displays. More importantly, the tone mapping operator can be changed on the fly to any desired operator without requiring any change in the pixel circuit. Simulation and test results are presented to show the pixel's ability to produce WDR images with over 6 decades of dynamic range and compressed images using TM algorithms such as Reinhard's and Drago's.