Motion tracking
PatchMaker in basically intended for 2D motion tracking, which involves determining the motion of a given object in the image plane. The object motion is considered as a series of transformations in the image plane, their parameter values being estimated by comparing each pair of consecutive frames in the sequence.
Before tracking can be started, the user needs to select one frame as a key frame and create (draw) a mask [A] in order to specify an object (or a region) the motion of which is to be tracked.
The tracking procedure then estimates interframe transformations to obtain the closest possible fit to the real object motion in the source video over for a number of frames in the forward [B] and backward [C] directions from the key frame.
The type of interframe transformations is determined by a motion model that can be selected among
See also:
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translation,
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translation + rotation (rigid motion),
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translation + rotation + scale,
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affine transformations.
The output of the tracking procedure is the sequence of transformations (the data layer) generated for a continuous range of video frames. The data layer content is uniquely determined the key frame mask and the tracking settings.
