Editing Inbetweening (section)

== Digital animation ==
{{See also|Interpolation (computer graphics)}}
[[Image:Tweening.gif|thumb|right|This animated GIF demonstrates the effects of [[Adobe Flash]] shape, motion, and colour tweening.]]
When animating in a [[Digital content|digital context]], the shortened term ''tweening'' is commonly used, and the resulting sequence of frames is called a ''tween''. Sophisticated animation software enables the animator to specify objects in an image and to define how they should move and change during the tweening process. The software may be used to [[artistic rendering|manually render]] or adjust transitional frames by hand or may be used to automatically render transitional frames using [[interpolation (computer graphics)|interpolation]] of graphic parameters.

Some of the earliest software that utilises automatic interpolation in the realm of digital animation includes [[Adobe Animate|Adobe Flash]]<ref>{{Cite book|url=https://www.awn.com/mag/issue1.12/AWNMag1.12.pdf|title=Animation World Magazine - March 1997|last=Calop|first=Guillaume|publisher=Animation World Network|year=1997|pages=55}}</ref> and Animo<ref>{{Citation|title=Animo Vectors| date=28 August 2007 |url=https://www.youtube.com/watch?v=z1OFfs7geaw| archive-url=https://ghostarchive.org/varchive/youtube/20211211/z1OFfs7geaw| archive-date=2021-12-11 | url-status=live|language=en|access-date=2020-01-17}}{{cbignore}}</ref> (developed by [[Cambridge Animation Systems]]) in the late 90s, and Tweenmaker,<ref>{{Citation|title=TweenMaker| date=6 July 2014 |url=https://www.youtube.com/watch?v=AQwzVeTxYgY| archive-url=https://ghostarchive.org/varchive/youtube/20211211/AQwzVeTxYgY| archive-date=2021-12-11 | url-status=live|language=en|access-date=2020-01-17}}{{cbignore}}</ref> released around 2006.<ref>{{Cite web|url=http://www.elecorn.com/tweenmaker/index.html|title=TweenMaker {{!}} Home|website=www.elecorn.com|access-date=2020-01-17}}</ref><ref>{{Cite web|url=https://download.cnet.com/TweenMaker/3000-2186_4-10619499.html|title=TweenMaker|website=Download.com|date=23 July 2015 |access-date=2020-01-17}}</ref> The [[free software]] program [[Synfig]] specializes in automated tweening.

"Ease-in" and "ease-out" in [[Computer animation|digital animation]] typically refer to a mechanism for defining the physics of the transition between two animation states, i.e., the linearity of a tween.<ref>{{Cite web|url=http://hosted.zeh.com.br/tweener/docs/en-us/misc/transitions.html|title=Tweener Documentation and Language Reference|website=hosted.zeh.com.br}}</ref> For example, an ease-in transition would start the animation out slowly, and then progressively get faster as the animation continues. An ease-out transition does the opposite, where the animation starts out quickly but then slows down.

The use of computers for inbetweening was enhanced by [https://www.ithistory.org/honor-roll/mr-nestor-burtnyk Nestor Burtnyk] and [https://graphicsinterface.org/awards/chccs-scdhm-achievement/marceli-wein/ Marceli Wein] at the [[National Research Council of Canada]]. They received a Technical Achievement [[Academy Award]] in 1997, for "pioneering work in the development of software techniques for computer-assisted keyframing for character animation".<ref>{{Cite web|url=https://graphicsinterface.org/awards/cdmp/burtnyk-pulfer-wein/|title=Nestor Burtnyk, Ken Pulfer, and Marceli Wein • Graphics Interface|website=Graphics Interface|language=en-CA|access-date=2020-01-17}}</ref>