introduction animate = “give life to” adding the dimension of time to graphics animator...

Introduction

• Animate = “Give life to”

• Adding the dimension of time to graphics

• Animator specifies movement of objects through time and space

Two main categories

• Computer-assisted animation– 2D & 2 1/2 D– Inbetweening– Inking, virtual camera, managing

data, etc

• Computer generated animation– Low level techniques

• Precisely specifying motion

– High level techniques• Describe general motion behavior

Introduction

• 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

• 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

Introduction

• 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

Perception

• 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– “positive afterimages”

• Persistence of vision is not persistence of motion

Perception

• Persistence of vision lower bound:– Playback rate of images– Critical flicker frequency

• Persistence of motion has an upper bound:– Object moves too quickly– Motion blur

• Two important rates:– Playback/refresh rate– Sampling/update rate

The early days• Persistence of vision: discovered in the

1800s.– Zoetrope– Flipbook– Thaumatrope

The early days

• End of the 19th centure introduced moving image by using a projector.– Magic Lantern and shadow puppets– Zoopraxinoscope (zoetrope + projector)– Kinetograph

• First motion picture viewer

The early days

• 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)

• Each image redrawn on rice paper and then filmed

The early days

• 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

The early days

• First animated character: Felix the Cat (Otto Messmer) in early 1920s.

• Disney came around end 1920s, introducing a number of innovations– Storyboards– Pencil sketches for reviewing motion– Multiplane camera– Using sound & colour

Multiplane Camera

• Move scene layers independently of camera

• Six directions of movement for each plane

Multiplane camera

• 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

The early days

• 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

MGM and Warner Brothers, etc.

Other Media Animation

• Computer animation is often compared to stop motion animation– Puppet animation

• Willis O’Brian (King Kong)

• Ray Harryhausen (Might joe Yong, Jason and the Argonauts)

Other Media Animation

• Claymation

• Sand animation

Physical object is manipulated, image captured, repeat

Production of Animation

• Preliminary story• Story board• Detailed story• Key Frames• Test shot• Pencil test• Inbetweening• Inking• Coloring

Computer Animationbasically follows this

pipeline

Computer Animation as Animation

• Lasseter translated traditional principles of animation to computer animation– Lasseter is conventionally trained animator

• Worked at Disney before going to Pixar• Many celebrated animations• Knick-knack (oscar-winning)

Computer Animation Research

In Research labs

• NYIT

Still frame from Gumby animation by Hank Grebe and Dick Lundin, 1984.

Computer Animation Research

• University of Utah– Films on walking and talking

figure – Animated hand and animated

face (1972)

• University of Pennsylvania– Human figure animation (Norm

Badler)

• MIRALab, Geneva– Virtual Humans (Daniel & Nadia

Thalmann)

Pioneering animation moviesPixar• Luxo Jr. (1986)

– first computer animation to be nominated for an Academy Award

• Red's Dream (1987)

• Tin Toy (1988)– first computer animation to win

an Academy Award

• Knick Knack (1989)

Early CG in film• Future World (1976)• Star Wars (1977)• Tron (1982, MAGI)

– Supposed to look like a computer• The Last Starfighter (1984)

– Use CG in place of models• Willow (1988, ILM)

– Morphing video– First digital blue screen matte extraction

• The Abyss (1989, ILM)• Lawnmower man (1992, Xaos, Angel Studios)

• Hollywood’s view of VR

Early CG in film

• Jurassic Park (1993, ILM)• Forrest Gump (1994, Digital

Domain)– Insert CG ping pong ball

• Babe (1995, Rhythm & Hues)– Move mouths of animals & fill

in background• Toy Story (1995, Pixar &

Disney)– First full length fully CG 3D

animation

Early CG on TV• Reboot (1995, Limelight

Ltd. BLT Productions)– Similar intention of “inside

computer”– First fully 3D Sat. morning

cartoon

• Babylon 5 (1995)– Routinely used CG models

as regular features

• Simpsons (1995 PDI)

More recent movies with CG• Final fantasy (2001)

– Fully 3D simulated environment

• Lord of the Rings (2001-2003)– One of the first movies

using crowds (Massive)• Polar express (2004)

– Fully motion-capture based

• The Shrek movies (2001, 2004, 2007)

• Avatar (2009)

Resources

• Milestones of the animation industry in the 20th Century– http://www.awn.com/mag/issue4.10/4.10pages/

cohenmilestones6.php3

• Brief History of NYIT Computer Graphics Lab – http://www.cs.cmu.edu/~ph/nyit/masson/nyit.html

• Rick Parent– http://www.cse.ohio-state.edu/~parent– http://old.siggraph.org/education/materials/

HyperGraph/animation/rick_parent/Intr.html