A method of calibrating an infrared (IR) camera including a pixel array housed in a housing, the pixel array having an image sensor and one or more parasitic heat sensing pixels arranged to receive infrared light from different portions of an interior surface of the housing, the method including: receiving, by a processing device, one or more readings from each of the parasitic heat sensing pixels and from each pixel of the pixel array; and generating, by the processing device based on the one or more readings, one or more conversion matrices for converting readings from the parasitic heat sensing pixels into pixel correction values for performing 2D signal correction of the image.