Markerless visual tracking methods track the position of a camera based solely on video information in unprepared environments. They can be used for realistic placement of virtual objects into video in augmented reality, for example. Typical solutions use an automatically reconstructed 3D map containing the relative positions of some identifiable surface points in the scene to find and track the camera position. The reconstruction process consists of identifying common points across images, triangulating common points and finding camera positions and simultaneously optimizing camera and point positions over multiple images in a process called bundle adjustment.