04797836 is referenced by 69 patents and cites 6 patents.

A method for orientating and animating video images using quaternions to provide smooth, predictable rotations in a digital video effect device. Euler angles for a new orientation are input by an operator and are converted into an appropriate quaternion. For incremental orientation changes the appropriate quaternion is combined with the current quaternion of the video image in either source or target space to form a new quaternion for the new orientation of the video image. A selected plurality of such new quaternions in a sequence make up the video effect keyframes. In executing the video effect a Bezier spherical linear algorithm is used to interpolate intermediate quaternions on a video field by field basis between neighboring pairs of keyframe quaternions based upon the source keyframe quaternion, the destination keyframe quaternion, a source outgoing keyframe quaternion, a destination incoming keyframe quaternion and an inbetweening time coefficient. The intermediate quaternions are fine tuned by referring to tension, continuity and bias parameters.

Title
Image orientation and animation using quaternions
Application Number
6/932805
Publication Number
4797836
Application Date
November 19, 1986
Publication Date
January 10, 1989
Inventor
David E Lake Jr
Penn Valley
CA, US
Francis A Witek
Cedar Ridge
CA, US
Agent
Francis I Gray
Assignee
The Grass Valley Group
CA, US
IPC
G09G 1/16
G06F 15/66
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