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Volume Morphing

 

The 3D volume morphing problem can be stated as follows. Given two volumes and , henceforth called the source and target volumes, we must produce a sequence of intermediate volumes, the morphs, meeting the following two conditions:

Realism:
The morphs should be realistic objects which have plausible 3D geometry and which retain the essential features of the source and target.
Smoothness:
The renderings of the morphs must depict a smooth transition from to .

From the former condition stems the major challenge in designing a 3D morphing system: as automatic feature recognition and matching have yet to equal human perception, user input is crucial in defining the transformation of the objects. The challenge for the designer of a 3D morphing technique is two-fold: the morphing algorithm must permit fine user control and the accompanying user interface (UI) should be intuitive.


 

 


Figure 1: Data flow in a morphing system. Editing comprises retouching and aligning the volumes for cosmetic reasons.


Our solution to 3D morphing attempts to meet both conditions of the morphing problem, while allowing a simple, yet powerful UI. To this end, we create each morph in two steps (see figure 1):

Warping:
and are warped to obtain volumes and . Our warping technique allows the animator to define quickly the exact shape of objects represented in and , thus meeting the realism condition.
Blending:
and are combined into one volume, the morph. Our blending technique provides the user with sufficient control to create a smooth morph.



Last update: 11 May 1995 by Apostolos "Toli" Lerios
tolis@cs.stanford.edu