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648 Chapter 12: Animation
accuracy. If the movie was digitized from film,
you should not per form deinterlacing because
the results will be less accurate. The deinterlacing
is performed temporarily on loaded frames and
doesn’t affect the original movie file.
Off—Disables deinterlacing. When no filteri ng is
required click this.
Odd—Interpolates using the odd lines.
Even—Interp olates using t he even lines.
Fade Display—Fades the movie in a Movie window
by 50 percent. Use this to see the tracker gizmos
more clearly.
Auto Loa d/ S av e—Saves the state of a tracking
setupandanypositiondatayou’veproducedtoa
specialfileassociatedwitheachmovie.Selecting
Auto Load/Save Settings causes the tracker to keep
this settings file up-to-date automatically as you
work in the t r acker. You can force a save at any
timebypressingtheSavebutton.Wheneveryou
openamoviefileintheCameraTrackerwithAuto
Load/Save turned on, the tracker reloads the state
of the tracking session from this settings file.
With Auto Load/Save Se t tings turned on, the
tracker construc ts the setting file automatically
and places it in the same folder as the mov ie,
named with the same prefix as the movie but with
filetypeMOT.Ifyoumovethemoviefiletoanew
folder, move the
.mot file with it so the t r acker can
find it. You can delete this file if you want to clear
the settings or if the file becomes corrupted for any
reason.
When AutoLoad/Save is tur ned off, you can open
adifferentmoviefileeitherwithanemptytracker
state or into the existing tracker state or save the
current tracker state into a new file. The name of
the current tracker file is displayed at the bottom
of the Mo vie rollout.
Save—Saves the state of the tracking setup, and any
position data produced to the current
.mot file.
Save As—Saves the current setup into a new
.mot file. This fi le becomes the destination for
subsequent Save operations.
Loa d—Load the tracker setup and position data
from another file.
Camera Tr acker: Movi e Wind o w
The tr acker gizmo displayed in the Movie window
consists of two enclosed boxes, a central pair of
cross hairs, and a tracker number. The inner box
surrounds the feature that will be tracked and
is called the
feature bounds box .Theouterbox
defines the frame-to-frame search and is called
the
motion search bounds box . You should place
the central cross-hair over the feature as close
as possible to the point corresponding to the
placement of its scene point object. It’s this center
coordinate that’s used in the camera match-move
correlation between image feature and scene Point
coordinates.
You should make the feature bounds box large
enough to enclose the feature and some of the
surroundingimagesenoughtogivethefeaturea
contrasting background of several pixels.