Parallel Tracking and Mapping for Controlling VTOL Airframe

Figure 8

Map building with the new keyframe addition. Camera successive positions where new keyframe is added are numbered from 1 to 7. (1) PTAMM after stereo initialization, (2) camera rotated to point into part of the scene without initialized features, (3) camera moved forward to obtain stereo separation, keyframe added, and new features initialized, (4) camera rotated again to look at another uninitialized part of the scene, (5) camera moved back for stereo, new features added, and so forth.