1. A method for gas detection in an infrared (IR) image depicting a scene, the method comprising: receiving a first IR image depicting the scene captured at a first time instance and a second IR image depicting the scene captured at a second time instance; performing image processing operations on image data derived from said first IR image and from said second IR image, to generate a collection of data representing the location of gas in one of the first or second IR image, wherein the image processing operations include: generating a temporal difference image based on the first IR image and the second IR image, performing edge detection in at least one of the first and the second IR image to provide detected edge information, creating an edge map comprising the detected edge information, wherein the pixels representing the detected edge information are assigned a first pixel value and the remaining pixels are assigned a second pixel value, and generating a processed difference image as part of the collection of data by combining the edge map with the temporal difference image such that the detected edge information is removed; and detecting gas within the scene by detecting gas representing pixels in the first or the second IR image based on thresholding the processed difference image to identify pixel coordinates of the gas representing pixels.