Hardware/software solution for high precision defect correction in digital image sensors

High resolution image sensors are now standard in imaging devices such as mobile phones with camera functionality. Resolution improvement in very small sensors is obtained by decreasing the pixel size but, in CMOS sensors, the likelihood of defective pixels also augments. Hence, sophisticated processing is necessary for achieving high quality images despite of noise and defects. This paper presents a hardware/software solution for high precision correction of defective pixels in an image sensor. The method maintains an always up-to-date map of the defective pixels and also allows detection of new defects as they show up during the lifetime of the sensor. The reliability of the map is assured by tracking the history of pixels defectiveness. The map is updated automatically and in real time without user intervention.