Calibration-free image sensor model for an arbitrary pan tilt plane of view

Abstract

This paper presents a calibration-free approach to modelling image sensors applicable in various pan-tilt planes of view. The proposed technique utilises known sensor's mechanical and electrical properties and constructs the model. The sensor's effective focal length is first estimated by known lens properties and is used to approximate the lens system by a thick lens and its properties. This is followed by the derivation of calibration-free distortion effects factor to characterise distortion effects inherent in the sensor, and subsequently generates the corrected image data. As a result, this does not require experimental setup or calibration and reduces the dependency on the quality of image data. Using sensors with three different specifications, an experiment was constructed to evaluate the accuracy and robustness of a model created by proposed modelling process. The proposed modelling process has also shown itself to be robust and, in comparison to conventional process, improved the accuracy significantly.