Background,Motivation and Objective The resolution of conventional ultrasound imaging is diffraction limited and corresponds roughly to the ultrasonic wavelength (100 μm). We have previously introduced the concept of ultrasound localization microscopy (ULM) by extracting precise positions for thousands of individual microbubbles per second from their punctual echo in ultrafast images [Couture et al. 2011, Desailly et al. 2013], allowing to surpass the diffraction-limit by an order of magnitude.