Device position dependant overlay for roadmapping

An image processor (IP) and an image processing method to support cardio- or neuro-interventions. An imager (100) acquires a series of fluoroscopic images (F) while an interventional tool progresses through a region of interest (ROI) such as a cardiac vasculature. Image processor (IP) operates to select from a plurality of stored angiograms (A) previously acquired of the region of interest a contextual one from which a contextual roadmap (RM) can be extracted. The contextual roadmap is selected to fit to both, a current cardiac phase and the current position of the device (GW). The selected contextual angiogram and its contextual roadmap is capable of showing the outlines of the vasculature (ROI) at the current device position at high contrast.