Abstract: The present disclosure relates to a method and processing device for obtaining a geographical coordinate for a position on the ground. The method comprises determining an initial pose of a video camera on-board an aerial platform,, continuously determining a pose of the video camera starting from the determined initial pose and from continuously updated video camera images and the textured 3D model of the environment, receiving a request for determining a geographical coordinate for a position on the ground, said request comprising a second image from the continuously updated video images in which second image a location of the position on the ground is indicated, and determining the geographical coordinate of the indicated position on the ground based on a determined pose of the video camera at the time of capture the second image, the second image and the textured 3D model of the environment.