User Manual

(measured in pixels) between tracks in the 2D image and the reconstructed 3D locators
reprojected back onto the image through the reconstructed camera. Ultimately, in trying to
achieve a low solve error, any value less than 1.0 pixels will generally result in a good track.
Avalue between 0.6 and 0.8 pixels is considered excellent.
Clean Tracks by Filter
Clicking this button selects tracks based on the Track Filtering options. If the Auto Delete
Tracks By Filter checkbox is activated, the selected tracks will be deleted as well.
Clean Foreground Tracks
Clicking this button makes a selection of the tracks on fast-moving objects that would otherwise
cause a high solve error. The selection is determined by the Foreground Threshold slider.
Foreground Threshold
This slider sets the detection threshold for finding the tracks on fast-moving objects. The higher
the value, the more forgiving.
Auto Delete Tracks by Filter
With this checkbox enabled, tracks that are selected by the Clean Tracks By Filter button will be
deleted. Enable the checkbox, and then press Clean Tracks By Filter. Any track that meets the
filtering options is then selected and deleted.
Auto Delete Foreground Tracks
With this checkbox enabled, tracks that are selected by the Clean Foreground Tracks button
will be deleted. Enable the checkbox, and then press Clean Foreground Tracks. Any track that
meets the foreground threshold criteria is deleted.
Accept Solve Error
This slider sets an acceptable maximum threshold level for the solve error. If the solve error is
greater than this value, the Camera Tracker will sweep the focal length setting in an attempt to
bring the solve error under the Accept Solve Error value. If the solver cannot find a solution, the
Camera Tracker will display a message in the console that the solver failed. If a solution cannot
be found, ideally you should try to input the correct focal length or alternatively manually clean
some noisy tracks then re-solve.
Auto Select Seed Frames
With this enabled, the Camera Tracker nominates two frames that will be used as a reference
for initiating the solve. These two frames are initially solved for and a camera is reconstructed,
and then gradually more frames are added in, and the solution is “grown” outward from the
seed frames. The choice of seed frames strongly affects the entire solve and can easily cause
the solve to fail. Seed frames can be found automatically or defined manually.
Disabling this will allow the user to select their own two frames. Manual choice of seed frames
is an option for advanced users. When choosing seed frames, it is important to satisfy two
conflicting desires: the seed frames should have lots of tracks in common yet be far apart in
perspective (i.e., the baseline distance between the two associated cameras is long).
Refine Focal Length
Enabling this will allow the solver to adjust the focal length of the lens to match the tracking
points. You can prevent the focal length being adjusted by setting the Focal Length parameter
in the Camera Tab.
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