A method for detecting motion in a video sequence comprising distorted image frames is provided. The method comprises determining (101) a spatial resolution distribution for the distorted image frames; determining (102) a motion detection sensitivity map for the distorted image frames, the motion detection sensitivity map comprising areas having different motion detection sensitivity levels, wherein the motion detection sensitivity map is determined based on the spatial resolution distribution; and detecting (103) motion in the video sequence based on the motion detection sensitivity map. A motion detecting component and a camera including such a component is also disclosed.