1. Method of detecting objects from terrestrial based mobile mapping data, wherein the terrestrial based mobile mapping data has been captured by way of a terrestrial based mobile mapping vehicle driving on a road having a driving direction, the mobile mapping data including laser scanner data, source images obtained by at least one camera and position and orientation data of the terrestrial based mobile mapping vehicle, wherein the laser scanner data includes laser points, each laser point having associated position and orientation data, and each source image comprises associated position and orientation data, the method comprising: retrieving a position and orientation of the terrestrial based mobile mapping vehicle; filtering the laser scanner data in dependence of the retrieved position and orientation of the terrestrial based mobile mapping vehicle to obtain laser points corresponding to regions of interest; retrieving a source image associated with the retrieved position and orientation of the terrestrial based mobile mapping vehicle; mapping the obtained laser points corresponding to regions of interest to image coordinates of the retrieved source image to generate a recognition mask; combining the generated recognition mask and the retrieved source image to obtain candidate 3D images representative of possible objects within the regions of interest; and detecting a group of objects from the obtained candidate 3D images.