The article presents a method of modeling the signal coming from a thermal imaging camera that allows to perform a comparative analysis of algorithms for determining the so-called optical-flow. The modeling method was created for the development of an inertial sensor determining the displacement of the vehicle based on the analysis of the image from a thermal imaging camera. As part of the development work, it was necessary to select the type of optical flow algorithm and optimize its parameters. The synthetic signal model allowed for quick prototyping and automatic optimization of its parameters. The article presents exemplary results of comparing the efficiency of SAD and Farnebäck algorithms in the context of application for thermal imaging.