Lecture 1: introduction
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Introduction to basic techniques in Computer
Animation
 Motion capture & synthesis, facial animation, IK, …
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Introduction to research topics
 Giving presentations
 Reading and evaluating research papers
 Writing an essay about an animation topic
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Hands-on experience with motion capture
 Short animation movie production
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Grading:
 Presentation (P)
 Animation movie (M) (and an Oscar for the
winning movie  )
 Essay (E)
 Final grade = 0.3*P + 0.3*M + 0.4*E
▪ Condition: E >= 5
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Attendance of the sessions is mandatory
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Papers/presentations:
 Papers are presented in teams of two
 Multiple presentations per session
 15-20 minutes per presentation
 10 minutes evaluation/discussion
 Evaluation forms
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15-20 minutes (divide slides over team
members)
Presentation should discuss the contents of
the paper
 What is it about, what is the contribution, what
are the drawbacks of the proposed method…
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After the presentation, there is time for
discussion/questions (10 minutes)
 Last slide should contain 2-3 discussion points
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Presentations will be evaluated by all using a
grading and evaluation form.
 Content
 Visual aids
 Delivery
 Ability to answer questions
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Presentation grade will be given to you the
next session.
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Introduction
Background
Paper content
Contributions of the method
Drawbacks of the method
Conclusion
Discussion points
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Preparing the presentation
 Read the paper thoroughly
 Read a few of the background papers to place the
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research
Identify advantages, drawbacks, and discussion
points
Collect images/movies
Contact the author in case of specific questions!
Do a ‘test-drive’ at home to check the
presentation is not too long or too short
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Tips for showing movies:
 VLC player
 Or: use Windows Movie Maker
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Please make sure that your movies work
properly on your laptop!
You may also use the computer in the lecture
room instead, but check that your
presentation works as it should!
Alternative to PowerPoint: Reveal.js
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To be done in teams of 4/5
Assignment: short animation movie
 Make a storyboard and a previz movie
 Record the animations in the mocap lab
 Animate one or more characters and make a nice
rendering
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Tools:
 MotionBuilder + Maya
 We have a number of 3D models of characters
 Look on the Internet for additional resources
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Planning of the motion capture lab visit
 BBG building, room K61 (basement)
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Show movies during last session!
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Essay:
 Between 4500-5000 words, including references
 Can be on any topic related to animation
▪ Motion capture
▪ Motion synthesis (graphs etc.)
▪ Facial animation
▪ Hand animation
▪ Animation & interaction (gestures etc.)
▪ Animation & emotions
▪ Skinning
Check the website regularly for updates:
http://www.cs.uu.nl/docs/vakken/mcanim
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Animate = “Give life to”
Adding the dimension of time to graphics
Animator specifies movement of objects
through time and space
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Computer-assisted animation
 2D & 2 1/2 D
 Inbetweening
 Inking, virtual camera, managing data,
etc
 Beauty and the Beast, Antz
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Computer generated animation
 Low level techniques
▪ Precisely specifying motion
 High level techniques
▪ Describe general motion behavior
 Toy Story, Frozen, Inside Out, Shrek
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Low-level techniques
 Shape interpolation
 Helps the animator fill in the details of the motion given
enough information
 Animator has a fairly specific idea of target motion
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High-level techniques
 Generate a motion given a set of rules or constraints
 Object motion is controlled by a model/algorithm
 Fairly sophisticated computation, such as physically-based
motion
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Another way of looking at this: level of
abstraction
Very low-level: animator colours every pixel
individually in every frame
Very-high level: tell the computer “make a
movie about a dog”
Challenge lies in developing tools that allow
animators to animate on different levels
Eye/brain assembles images and interprets them as
continuous movement
 Persistence of vision: sequence of still images
shown at a fast enough rate to induce sensation of
continuous imagery
 Eye retains visual imprint once stimulus is removed
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 “positive afterimages”
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Persistence of motion is
the sensation that
something is moving.
 It is not the same as the
persistence of vision.
 Motion is perceived but not
necessarily due to a
succession of still images,
e.g., lights on a movie
marquee
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Phi phenomenon is the optical illusion
that when two lights are rapidly turned on
and off in succession something appears
to move backwards and forwards
between them while the lights stay
stationary
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Beta Movement is an optical illusion
whereby a series of static lights on a
screen creates the illusion of a smoothly
flowing scene.
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Max Wertheimer, 1912
 One of the co-founders of Gestalt psychology
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Flicker: the image flickers when persistence of
vision does not occur
 When the perception of continuous imagery fails to be
created, the display is said to flicker.
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Critical flicker frequency is the rate at which the
images must be shown in order to maintain
persistence of vision.
 Different things that affect it are: room lighting, viewing
distance, etc. The critical flicker frequency determines the
lower bound on the playback rate.
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Lower bound:
 Critical flicker frequency: lower limits for
establishing the perception of continuous
imagery
 Playback/refresh rate: number of images
displayed per second
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Upper bound:
 Upper limits the eye can perceive motion,
if an object moves too quickly
 Motion blur: the receptors in the eye will
not be able to respond fast enough for the
brain to distinguish sharply defined,
individual detail and motion blur occurs.
Sampling rate
0
1/30 sec
Reality
0
1/60 sec
1/30 sec
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Entire motion of the object is missed because
sampling rate is too low to capture the fast
motion of the object
Displaying a rapidly moving object by a single
instantaneous sample results in jerky motion
 similar to that of live action under a strobe light
(and this is often called strobing).
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Conventional animation has developed its own
techniques for representing fast motion.
 Speed lines can be added to moving objects
 Objects can be stretched in the direction of travel, or
both speed lines and object stretching can be used
Human eye: If the eye is not tracking the object and
the object moves across the field of view, receptors
will receive various samples from the environment
integrated together, forming a cumulative effect in
the eye-brain
 Movie camera will open its shutter for an interval of
time, and an object moving across the field of view
will create a blurred image on that frame of the film
 Synthetic camera can (and should) consider a frame
to be an interval of time instead of an instance in time.
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 Accurately calculating the effect of moving objects in an
image requires a nontrivial amount of computation.
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Two important rates:
 Playback/refresh rate: number of images displayed per
second
▪ Related to flicker
 Sampling/update rate: number of distinct images that
occur per second
▪ How jerky the motion will appear
 e.g. Saturday morning cartoons have a sampling rate of 6
frames per second (fps) but each image is repeated five
times, so the playback rate is 30 fps.
 History of frame rate:
https://www.youtube.com/watch?v=mjYjFEp9Yx0
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Persistence of vision:
discovered in the 1800s.
 Zoetrope
 Flipbook
 Thaumatrope
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Eadweard Muybridge
“Animal Locomotion” - 1887
“Animals in Motion” - 1899
“The Human Figure in Motion” - 1901
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End of the 19th century introduced moving
image by using a projector.
 Magic Lantern and shadow puppets
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Zoopraxiscope (zoetrope + projector)
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Kinetograph/kinetoscope (Edison and
Dickson, 1988)
 First motion picture camera/viewer
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Cinematograph
Lumiere brothers, 1895
Arrival of a Train at La Ciotat, 1896
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Animation movie pioneers
 J. Stuart Blackton (smoke effect, 1900)
▪ First animated cartoon in 1906
▪ Used a chalkboard for drawing and erasing frames
 Emile Cohl (Fantasmogorie,
1908)
 Winsor McCay (Little Nemo, 1911)
▪ Each image redrawn on rice paper and then filmed
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Major technical developments by
John Bray (1910):
 compositing multiple layers of drawings
into a final image (celluloid)
 using grayscale
 Drawing background on long sheet of
paper for panning
Max Fleischer (Betty Boop), Walter
Lantz (Woody Woodpecker)
 Fleischer patented rotoscoping in
1915
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First animated character: Felix the
Cat (Otto Messmer) in early
1920s.
 Disney came around end 1920s,
introducing a number of
innovations
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Storyboards
Pencil sketches for reviewing motion
Multiplane camera
Using sound & colour
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Move scene layers independently of camera
Six directions of movement for each plane
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Powerful tool:
 More effective zoom
▪ Move foreground image to the side
 Parallax effect
▪ Moving planes at different rates
 Adding depth cues
▪ Blur the images on more distant planes
 Introduce motion blur by fast moving planes
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Sound was added for the first time in
Steamboat Willie (1928)
Disney promoted idea that mind of the
character was the driving force of the action
 Analysis of real-life motion
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Computer animation is
often compared to stop
motion animation
 Puppet animation
▪ Willis O’Brian (King Kong)
▪ Ray Harryhausen (Mighty
Joe Yong, Jason and the
Argonauts)
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Claymation
Sand animation
Physical object is manipulated, image
captured, repeat
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Preliminary story
Story board
Detailed story
Key Frames
Test shot
Pencil test
Inbetweening
Inking
Coloring
Computer Animation
basically follows this
pipeline
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Lasseter translated traditional principles of
animation to computer animation (1980s)
 Lasseter is conventionally trained animator
▪ Worked at Disney before going to Pixar
▪ Chief creative officer Pixar
▪ Many celebrated animations
▪ Toy story, Wall-e, Frozen, Inside Out
Pixar
 Luxo Jr. (1986)
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Red's Dream (1987)
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Tin Toy (1988)
 first computer animation to win an
Academy Award
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Knick Knack (1989)
In Research labs (from 1970s)
 New York Institute of Technology (NYIT)
 Gumby (Presented at SIGGRAPH '84 & '85 Electronic
Theatres)
Still frame from Gumby animation by Hank Grebe and Dick Lundin, 1984.
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University of Utah
 Films on walking and talking figure
 Animated hand and animated face
(Ed Catmull (president of Pixar now),
1972) (Fred Parke, Talking face, 1974)
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University of Pennsylvania
 Human figure animation (Norm
Badler, 1975)
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MIRALab, Geneva
 Virtual Humans (Daniel & Nadia
Thalmann, 1980s)
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Future World (1976)
Star Wars (1977)
Tron (1982, MAGI)
 Supposed to look like a computer
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The Last Starfighter (1984)
 Use CG in place of models
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Willow (1988, ILM)
 Morphing video
 First digital blue screen matte extraction
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The Abyss (1989, ILM)
Lawnmower man (1992, Xaos, Angel Studios)
 Hollywood’s view of VR
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Jurassic Park (1993, ILM)
Forrest Gump (1994, Digital
Domain)
 Insert CG ping pong ball
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Babe (1995, Rhythm & Hues)
 Move mouths of animals & fill in
background
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Toy Story (1995, Pixar &
Disney)
 First full length fully CG 3D
animation
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Reboot (1995, Limelight
Ltd. BLT Productions)
 Similar intention of “inside
computer”
 First fully 3D Sat. morning
cartoon
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Babylon 5 (1995)
 Routinely used CG models as
regular features
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Simpsons (1995 PDI)
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Final fantasy (2001)
 Fully 3D simulated
environment
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Lord of the Rings (20012003)
 One of the first movies using
crowds (Massive)
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Avatar (2009)
Benjamin Button (2008)
Prometheus (2012)
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Benjamin Button
 https://www.youtube.com/watch?v=qYss9eR7ewc
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Avatar
 https://www.youtube.com/watch?v=L6JXUoWeZ7Q
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L.A. Noire
 https://www.youtube.com/watch?v=q2EG5J05048
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Milestones of the animation industry in the 20th
Century
 http://www.awn.com/mag/issue4.10/4.10pages/cohenmile
stones6.php3
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Brief History of NYIT Computer Graphics Lab
 http://www.cs.cmu.edu/~ph/nyit/masson/nyit.html
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Rick Parent
 http://www.cse.ohio-state.edu/~parent
 http://old.siggraph.org/education/materials/HyperGraph/a
nimation/rick_parent/Intr.html