After Effects
3D Camera Tracker
This tool tracks multiple points in a scene to essentially produce a point cloud that allows the program to locate the camera.
One you select Track Camera the software immediately starts to track using the default search parameters. For simple movement or stationary cameras this should be sufficient.
After it has analysed all the frames of the footage it will either solve or fail to solve. The analysis may also fail to solve on only some frames.
The default track isn't terrible, but it tracks the moving subject and has some clearly mis sized tracking points on the wall at the end which suggest that it's confused to where the camera is. There also are not enough tracking points in the later frames to suggest that it's been successful.
Bad tracking points can simply be selected and deleted.
After Effects will then reanalyse how this affects the track.
In this case the tracking failed at the end, this is expected with how few tracking points it followed in the later frames.
One solution to forcing the tracker to analyse the scene properly is to mask out any areas that are causing issues - the person at the end - and to retrack.
If you don't precomp the masking, then it will have the same results.
Despite masking the tracker is still getting confused by the subject walking past the good tracking sites. Now we can explore some more options in the tracker settings - primarily using the 'detailed analysis' option. This increases the accuracy of the track, but is more resource intensive and slower.
Clearly the detailed analysis track has been more successful, with multiple tracking markers on each point, as well as reacquiring the obscured markers. More points does introduce the potential for more noise in the track however, and bad markers like the ones on the moving subject should still be removed.
Once the tracking is complete, select some points to form a plane, right click and create a camera. Creating a solid will help visualise how the track sticks when played back.
The AfterEffects camera tracker is a very friendly to use, mostly automated system. It won't fair well on very complicated scenes, or scenes with a lot of actor movement. But for simple tracks it does an effective job with minimal effort.
After Effects 2D Trackers
Track Motion
This is a simple point tracker. It's capable of tracking one or two points and the scale/rotation between them. Although it's a 2d track, it can be useful to track a specific point on a surface.
Stabilise Motion
This is similar to a point(s) track, except that it's generally applied to the video layer to reduce any camera shake, or to keep focus on a particular subject.
Warp Stabilizer
This uses more tracking points - similar to the 3d camera track - to stabilise motion in the footage. It's different to stabilise motion as it's analyses the whole footage instead of focusing on one or two points
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