Established in 1900 by the family of Charles Goodwin Sands (Cornell class of1890), theSands Medal is traditionally given for the best undergraduate thesis in oneof the three branches of the Cornell University School of Art, Architecture,and Urban Planning. The award is not given every year, and in some years, morethan one award is given. I was awarded the medal for my Bachelor ofArchitecture thesis [1]. The thesis describes a computer animation system forline art, based on user-guided interpolation between hand-drawn keyframes. Myadvisor wasDonald Greenberg.
My system was based on the pioneering work of Nestor Burtnyk and Marceli Wein[2], but updated to run on a more modern real-time vector display (the Evansand Sutherland Picture System). Two screenshots from the system are shownabove. They represent two keyframes in an animated movie made by fellowstudent Jose Gelabert. Since both drawings contain the same number of strokes,the system could interpolate linearly between them, producing a sequence ofintermediate drawings. Using Burtnyk and Wein's system, artist PeterFoldes made the award-winning filmHunger (1974).
After completing my thesis, I continued working in this area, leadingto a Master of Science in Architecture two years later [3]. This second thesisdescribes a system for online drawing (or optical scanning) of cartoondrawings, user-guided linear interpolation between these drawings, flooding ofenclosed areas in the drawings with color or texture, online painting (oroptical scanning) of cartoon backgrounds, and merging together of the drawingsand backgrounds to create composite frames of an animation sequence. Myadvisor once again was Don Greenberg.
Although many components of the system described in my Master's thesis wereinspired by contemporary work being done by Alvy Ray Smith and Ed Catmull atthe New York Institute of Technology [4], my system incorporated a number ofnew elements. First, the area flooding algorithm (equivalent to the paintbucket in Adobe Photoshop) was particularly efficient [5]. Second, the mergingstep permitted independent geometric transformation of each artwork layer, withthe goal of simulating Walt Disney's multiplane camera, and it included aninteractive program for positioning these layers in three dimensions [6]. Thismerging system is further described in Bruce Wallace's SIGGRAPH 1981 paper [7],his Master's thesis [8], and a paper I wrote for a small European conference[9].
Finally, although mine was not the first paint program to incorporate asimulated airbrush [10], it may have been the first to incorporate aweighted, mask-driven tinting brush. My Master's thesis also contained thefirst published description of such a brush.This description, together with aresurrection of Alvy Ray Smith's 1978 paint program, was used to prove theexistence of prior art inAdobe v. Quantel (1996), a highly publicized trialin which Quantel claimed (falsely) to have invented the computer airbrush,which Adobe uses in Photoshop.
After the completion of my Master's thesis, Don Greenberg and I tried toconvince the Walt Disney's feature animation group to incorporate computergraphics into their production process. Unfortunately, several of the"nine old men",who had worked for Disney since the 1930's, were still active, and they wouldhave none if it. By the mid-1980's, these gentlemen had all retired, and Pixarwas able to convince Disney to explore the new technology. The system theyco-developed was calledCAPS(Computer Animation Production System). It ultimately won theman academy award in 1992 for its use inBeauty and the Beast.
Although we were unsuccessful at Disney, we managed to convince Hanna-BarberaProductions to employ our system in the television animation market.Hanna-Barbera was on the verge of closing down domestic production due tospiraling labor costs, and they saw our system as a way to forestall doing this.The animator's union didn't believe them, nor did they relish the prospect ofcomputerization, leading to a bitter strike in 1982. In the end, the animatorslearned to use our system, which remained in production until 1996. At itspeak in the late 80's, one third of Hanna-Barbera's yearly domestic productionwent through our system, including The Flintstones, Scooby-Doo, and othershows. Ultimately, domestic labor costs become too high even for thecomputerized production line, and the system was sold to James Wang Filmsof Taiwan. They ported it to PCs and marketed it for several years under thename Animaster. The original technical team at Hanna-Barbera Productionsconsisted of myself, Bruce Wallace, Chris Odgers, Bennett Leeds, Jim Mahoney,Steve McDaniel, and Tim Victor. Our chief power user from the production sideof the company was Ann Tucker. Interestingly, Ann subsequently went to workfor Disney, becoming their chief power user as well.
[1]Levoy, M.,A Computer-Assisted Keyfame Animation System.Bachelor's thesis, Cornell University, 1976.
[2] Burtnyk, N., Wein, M.,Computer Generated Key-Frame Animation,J. SMPTE, 80(3), March, 1971, pp. 149-153.
[3]Levoy, M.,Computer-Assisted Cartoon Animation.Master's thesis, Cornell University, 1978.
[4]Catmull E.,The problems of computer-assisted animation,Proc. ACM SIGGRAPH '78, pp. 348-353.
[5]Levoy, M.,Area Flooding Algorithms,SIGGRAPH '81 Two-Dimensional Computer Animation course notes,Dallas, Texas, August, ACM, 1981, pp. 6-12. With corrections made in 1982.
[6]Levoy, M.,A Computer Animation System Based on the Multiplane Technique,Proc. ACM SIGGRAPH '77,Vol. 11, No. 2, San Jose, California, July, 1977, pp. 65-71.
[7] Wallace, B.A.,Merging and Transformation of Raster Images for Cartoon Animation,Proc. ACM SIGGRAPH '81,Vol 15, No. 3, 1981, ACM, pp. 253-262.
[8] Wallace, B.A.,Automated production techniques in cartoon animation.Master's thesis, Cornell University, 1982.
[9]Levoy, M.,The Design And Implementation of a Large-ScaleComputer-Assisted Cartoon Animation System,Proc. Datorgrafikdagar conference,Linkoping, Sweden, June, 1983.
[10]Smith, A.R., Paint, Technical Memo 7, New York Institute of Technology,July 20, 1978. Also issued as tutorial notes at SIGGRAPHs 1978-1982.