Brightness calibration of charge-coupled device camera systems

Brightness calibration of vision sensors is an important step in developing machine vision applications, yet it is often ignored and overlooked. It en ables the accurate representation of image intensity readings with respect to a common linear brightness scale that is proportional to the scene irrad iance. We present a brightness calibration procedure for CCD camera systems . We also describe the characteristics of today's CCD cameras, which are ke y to their effective use as well as the visual brightness sensory informati on in industrial applications. Aspects of brightness measurement are discus sed. Results from calibrating a stereo CCD camera system and testing the ca librated system are also presented and discussed. (C) 2000 society of Photo -Optical Instrumentation Engineers. [S0091-3286(00)00302-0].