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The automatic tracking process can be launched from the Summary panel ( AUTO button), by the batch file processor, or controlled manually. By breaking the overall process down into sub-steps, you can partially re-run it with different settings, saving time. Though normally you can launch the entire process with one click, the following write-up breaks it down for your education, and sometimes you will want to run or re-run the steps yourself.
The full automatic tracking process has several stages:
1. finding potential trackable points, called blips
2. linking blips together to form paths
3. selecting some blip paths to convert to trackers
4. optionally fine-tuning the trackers , which re-analyzes the trackers using supervised tracking techniques to improve their accuracy,
5. running the solver to find the 3-D coordinates of the trackers, as well as the camera path and field of view,
6. optionally, automatically running a tracker cleanup and refining (re-solving) the scene again with the (hopefully!) improved tracking data,
7. optionally, automatically , placing the scene in the 3-D environment by assigning a coordinate system .
After the automatic tracking process runs, you should clean up trackers and create a coordinate system manually, if it hasn't been done automatically, and then you'll export to your 3-D compositing or animation package, but those topics are discussed separately and are the same for automatic and supervised tracking.
Note : The tracker cleanup stage above is labeled for experts because if the initial solve doesn't go well—for example you have unmasked actors walking around—the tracker cleanup will make the situation worse, not better. If you're not certain the track and solve will go well, you're better off examining them yourself and making any necessary changes before running the cleanup. If you expect it to go well and it doesn't, you can undo the different stages of AUTO individually.
The overall 2-D automatic tracking process is controlled from the Features Panel.
Typically, blips are computed for the entire shot length with the Blips all frames button. They can be (re)computed for a particular range by adjusting the playback range, and computing blips over just that range. Or, the blips may be computed for a single frame, to see what blips result before tracking all the frames, or when changing blip parameters.
frame.
As the blips are calculated, they are linked to form paths from frame to frame to
Finally, complete automatic tracking by clicking Peel All, which will select the
best blip paths and create trackers for them. Only the blip paths of these trackers will be used for the final camera/object solution.
You can tweak the automatic tracking process using the controls on the Advanced Features panel, a floating dialog launched from the Feature control panel.
You can delete bad automatically-generated trackers the same as you would a supervised tracker; convert specific blip paths to trackers; or add additional supervised trackers. See Combining Automatic and Supervised Tracking for more information on this subject.
If you wish to completely redo the automated tracking process, first click the Delete Leaden button to remove all automatic trackers (ie with lead-gray tooltip backgrounds), and the Clear all blips button. After changes to the Roto splines , you may also need to click Link Frames—in most cases you will be prompted for that.
Note that the calculated blips can require tens of megabytes of disk space to store. After blips have been calculated and converted to trackers, you may wish to clear them to minimize storage space. The Clean Up Trackers dialog encourages this. (There is also a preferences option to compress SynthEyes scene files, though this takes some additional time when opening or saving files.)
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