Continuous recovery for real time pan tilt zoom localization and mapping

We propose a method for real time recovering from tracking failure in monocular localization and mapping with a Pan Tilt Zoom camera (PTZ). The method automatically detects and seamlessly recovers from tracking failure while preserving map integrity. By extending recent advances in the PTZ localization and mapping, the system can quickly and continuously resume tracking failures by determining the best way to task two different localization modalities. The tradeoff involved when choosing between the two modalities is captured by maximizing the information expected to be extracted from the scene map. This is especially helpful in four main viewing condition: blurred frames, weak textured scene, not up to date map and occlusions due to sensor quantization or moving objects. Extensive tests show that the resulting system is able to recover from several different failures while zooming-in weak textured scene, all in real time.