[comp.graphics] rotoscoping

cs161fhn@sdcc10.ucsd.edu (Dennis Lou) (10/23/90)

What is rotoscoping?  Where can I learn about it?

I have Foley and Van Dam's
_Fundamentals_of_Interactive_Computer_Graphics_ but it doesn't say
anything about rotoscoping.  I have also searched the past 250
articles and sent a request to the graphics bibliography archive
server.

Thanks


-- 
Dennis Lou            | "But Yossarian, what if everyone thought that way?"
dlou@ucsd.edu         | "Then I'd be crazy to think any other way!"
[backbone]!ucsd!dlou  +----------------------------------------------------
dlou@ucsd.BITNET      cs161fhn@sdcc10.ucsd.edu

andyrose@batcomputer.tn.cornell.edu (Andy Rose) (10/23/90)

Rotoscoping means (in video production) editing frames of live action
on a frame by frame basis to add animation.
An example: Take 15 seconds of live action of Peggy Fleming skating.
Use a frame grabber to get each frame from analog to digital.
Break out the old Quantel paintbox and add a few sparkles around Peggy's skates.
Write the frame out to back out to tape (convert from digital back to analog)
repeat (15sec*30fps = 450 frames).

It expensive (@ $40/hr for Quantel operator) and it can look very bad. 
It can also look very good.

andy
-- 
Andrew Newkirk Rose '91 Department of Visualization CNSF/Theory Center
632 E & T Building, Hoy Road Ithaca, NY 14583  
607 254 8686  andy@cornellf.tn.cornell.edu

v134kkut@ubvmsb.cc.buffalo.edu (David W Tinklepaugh) (10/23/90)

In article <13485@sdcc6.ucsd.edu>, cs161fhn@sdcc10.ucsd.edu (Dennis Lou) writes...
> 
>What is rotoscoping?  Where can I learn about it?
> 
>I have Foley and Van Dam's
>_Fundamentals_of_Interactive_Computer_Graphics_ but it doesn't say
>anything about rotoscoping. 

That is because rotoscoping has little to do with 'computer graphics' as is
most commonly discussed here.  Rotoscoping (as I know it) is taking a 
video[tape] and displaying it one frame at a time.  You then draw an picture 
over it with a computer paint package using objects in the video as a 
reference, then sending the computer drawn picture (usually excluding the 
origonall video) to another vcr, to be recorded frame by frame.

if you want to read about it I suggest looking at books on digital video effects
(DVE), video editing, or video post-production work.  
       ______________________________________________________________________
      /                               /                              \      /
     /    -Dave-   U. of Buffalo     /    Wrap it up, I'll take it!   \    /
    /   v134kkut@ubvmsa (bitnet)    /      -Fabulous Thunderbirds      \  /
   /_______________________________/____________________________________\/

mark@calvin..westford.ccur.com (Mark Thompson) (10/23/90)

In article <13485@sdcc6.ucsd.edu> cs161fhn@sdcc10.ucsd.edu (Dennis Lou) writes:
>
>What is rotoscoping?  Where can I learn about it?
>I have Foley and Van Dam's
>_Fundamentals_of_Interactive_Computer_Graphics_ but it doesn't say
>anything about rotoscoping.

You won't find it in the standard computer graphics references because
rotoscoping is not necessarily a computer graphics technique. Rotoscoping
is a method of animation in which live action of real people, characters,
objects, etc. are captured (via film, video, etc.) and then either
traced or 'painted' (electronically or by hand) frame by frame to give
a very life-like look. The animated film "Wizards" used this technique
extensively in which old WWII war footage was used. It is an excellent
method for animating realistic motion. I can't point you to any specific
references, but if you look into books on animation (not computer animation)
you will most likely find it descibed more thoroughly. Hope this helps.
+--------------------------------------------------------------------------+
|  Mark Thompson                                                           |
|  mark@westford.ccur.com                                                  |
|  ...!{decvax,uunet}!masscomp!mark   Designing high performance graphics  |
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robert@texas.asd.sgi.com (Robert Skinner) (10/24/90)

In article <13485@sdcc6.ucsd.edu>, cs161fhn@sdcc10.ucsd.edu (Dennis Lou)
writes:
|> 
|> What is rotoscoping?  Where can I learn about it?
|> 
|> I have Foley and Van Dam's
|> _Fundamentals_of_Interactive_Computer_Graphics_ but it doesn't say
|> anything about rotoscoping.  I have also searched the past 250
|> articles and sent a request to the graphics bibliography archive
|> server.
|> 
|> Thanks

There is another form of rotoscoping that is sometimes used in computer
graphics to capture motion for animation or motion studies.  If video
tape an actor from two angles, you can use triangulation to determine
the 3D coordinates of key points on the body, usually joints.  You now
have what you need to animate a synthetic actor going through the same
motion.

Rotoscoping was used to generate the motions of Abel's "Sexy Robot"
commercial (~ 1986?), and for the tiger in Bio-Sensor (1984).  I'm
sure there are others, although good animators and faster dynamics
simulators are catching up on rotoscopings inherent limitations

	* motion for which there are no actors (dinosaurs)
	* motion that is hard or impossible to record (free fall from 
	  a plane, or something in outer space)
	* motion that is dangerous to the actor (being thrown from a
	  rolling automobile)

Robert Skinner
robert@sgi.com

	When two people are under the influence of the most violent,
	most insane, most delusive, and most transient passions, they
	are required to swear that they will remain in that excited,
	abnormal, and exhausting condition unconditionally until death
	do them part.
			-- George Bernard Shaw

rhbartls@watcgl.waterloo.edu (Richard Bartels) (10/24/90)

In article <1990Oct23.204359.18883@odin.corp.sgi.com> robert@sgi.com writes:
>
>There is another form of rotoscoping that is sometimes used in computer
>graphics to capture motion for animation or motion studies.  If video
>tape an actor from two angles, you can use triangulation to determine
>the 3D coordinates of key points on the body, usually joints.  You now
>have what you need to animate a synthetic actor going through the same
>motion.
>

For those who have seen "A Public Service Announcement" by
Dave Forsey, Phil Barry, et. al., this is precisely how the dragon
was done.  Dave's hand was fitted with sensor-points and triangulated
as he went through hand-puppet motions.  This provided joint motions,
and the dragon was a spline surface that surrounded the joints
with attachment constraints defined at strategic locations.

(Dave is en route to UBC, so I hope he'll forgive me for popping
in like this while he's out of touch.)

-Richard

cdshaw@cs.UAlberta.CA (Chris Shaw) (10/25/90)

In article andyrose@batcomputer.tn.cornell.edu (Andy Rose) writes:
>Rotoscoping means (in video production) editing frames of live action
>on a frame by frame basis to add animation.
>An example: Take 15 seconds of live action of Peggy Fleming skating.
>
>Andrew Newkirk Rose '91 Department of Visualization CNSF/Theory Center

Another approach is to take some live action, digitize the frame-by-frame
positions of the limbs of the actor, and use this 2D data to animate a
computer-rendered character. If multiple cameras are used to simultaneously
film the actor's motion, you can get 3D limb position data and can render 3D
synthetic characters. The advantage is that the motion is realistic--because
it's real motion. The disadvantage is that it's "canned". That is, once the
actor goes home, all you've got is the recorded motion. If you want more, do
another film shoot.

The "sexy robot" can commercial that ran during a Super Bowl in the mid 80's
is a classic example. The picture was synthetic (a chrome-plated woman), but
the motion was supplied by an actress.
--
Chris Shaw     University of Alberta
cdshaw@cs.UAlberta.ca           Now with new, minty Internet flavour!
CatchPhrase: Bogus as HELL !

labman@ecr.mu.oz.au (Bruce Robertson) (11/12/90)

In article <61306@masscomp.ccur.com>, mark@calvin..westford.ccur.com (Mark Thompson) writes:
> In article <13485@sdcc6.ucsd.edu> cs161fhn@sdcc10.ucsd.edu (Dennis Lou) writes:
> >
> >What is rotoscoping?  Where can I learn about it?
> >I have Foley and Van Dam's
> >_Fundamentals_of_Interactive_Computer_Graphics_ but it doesn't say
> >anything about rotoscoping.
> 
> traced or 'painted' (electronically or by hand) frame by frame to give
> a very life-like look. The animated film "Wizards" used this technique
> extensively in which old WWII war footage was used. It is an excellent

 I believe that the light saber fights in the Star Wars trilogy ser also
 rotoscope work.

 regards, 

  Bruce Robertson                               | labman@gondwana.ecr.mu.OZ.AU
  Department of Engineering Computer Resources, | labman@128.250.1.63
  C/o Faculty of Engineering,                 | Besides; It's not the Principle
  University of Melbourne, 3052. AUSTRALIA    | of the thing, it's the money.