Fast and easy radiometric calibration method integration time insensitive for infrared thermography

•The radiometric calibration is a crucial step in thermography.•The radiometric calibration is a time consuming and complex procedure.•An integration time insensitive radiometric calibration based on radiance is fast and easy. The radiometric calibration of an infrared camera is a crucial and unavoidable step to obtain an accurate temperature measurement. The calibration does the link between the sensor digital levels and the actual radiometric temperature. Although this step is critical and necessary to obtain meaningful measurement, it is a complex and time-consuming procedure, which requires many experimental data acquisitions and an algorithm to process them. This article proposes a method based on the radiance data processing allowing an easily and quickly radiometric calibration. Thanks to the proposed method, an integration time insensitive radiometric calibration is obtained from only two different observed steady and homogeneous thermal conditions (using a black body or equivalent).