A brief intro to how CGI works and what is CGI? All those green screens that you have seen in movies. Yes, that thing! What is that? and how it works? you will get to know it from this PPT.
1. COMPUTER
GENERATED
IMAGERY
S U B M I T T E D T O : S U B M I T T E D B Y:
M R S . VA I S H A L I K A U S H I K S H U B H R A N K R A S T O G I
R O L L N O . : 0 0 2 3 5 3 2 4 4 1 7
2. INTRO;-
• What is Animation?
• Animation Techniques
• What is Computer Animation and CGI?
• Techniques Involved In Production Of
CGI
• What are the Softwares require in CGI?
• How to produce CGI animation?
• Components of CGI
• Applications/Uses of CGI
• Movies made with extensive CGI
• Sources
4. WHAT IS ANIMATION OR ANIMATE?
• At its most basic, animate means simply “to give life to” while inanimate means not living, not
moving around. But animate also means spirited, or brought to life.
• Animate derives from the Latin anima "life, soul, spirit." When you seem particularly filled
with life, or high-spirited, if you laugh loudly, or use broad gestures, you're animated.
• The word Animation is generated from word 'anime' which means life. Animation is the rapid
display of a sequence of images of 2-D or 3-D artwork or model positions in order to create
an illusion of movement.
5. ANIMATION TECHNIQUES
• Traditional animation (also
called cel animation or hand-
drawn animation) was the
process used for most animated
films of the 20th century.
• The individual frames of a
traditionally animated film are
photographs of drawings, first
drawn on paper.
• To create the illusion of
movement, each drawing
differs slightly from the one
before it.
Patent drawing for Fleischer's original
rotoscope. The artist is drawing on a
transparent easel, onto which the movie
projector at the right is beaming an image of a
single movie frame.
An example of traditional
animation, a horse animated
by rotoscoping from Eadweard
Muybridge's 19th-century
photos
6. The bouncing ball animation (below)
consists of these six frames.
A projecting praxinoscope, 1882, here shown
superimposing an animated figure on a separately
projected background scene
7. • Full animation refers to the process of producing high-quality traditionally animated films that
regularly use detailed drawings and plausible movement, having a smooth animation.
• Fully animated films are animated at 24 frames per second, with a combination of animation
on ones and twos, meaning that drawings can be held for one frame out of 24 or two frames
out of 24.
8. • Stop-motion animation is used to describe animation created by physically manipulating real-
world objects and photographing them one frame of film at a time to create the illusion of
movement.
– Puppet animation
– Clay animation
Characters in the animated series From Ilich to
Kuzmich
A clay animation scene from
a Finnish television commercial
9. 1993 – The Nightmare before Christmas.
2009 –
The
Fantastic
Mr. Fox
2009 -
Coraline
2005 - Wallace & Gromit: The Curse of the Were-Rabbit
FEATURE FILMS WHICH USED STOP MOTION TECHNIQUE
11. WHAT IS COMPUTER ANIMATION AND CGI?
• Computer animation is the process used for generating animated images. The more general
term COMPUTER-GENERATED IMAGERY (CGI) encompasses both static scenes and dynamic images,
while computer animation only refers to the moving images.
• Computer-generated imagery (CGI) is the application of computer graphics to create or contribute to
images in art, printed media, video games, films, television programs, shorts, commercials, videos,
and simulators.
12. TECHNIQUES INVOLVED IN
PRODUCTION OF CGI
• There are many techniques that are used in the process of producing any image on the computer screen
from most basic to most complex one.
• Techniques used are:-
– Rendering
• Ray tracing
• Ray Casting
• Rasterized 3D
– Skeletal animation
– Morphing
– Composting
– Green Screen/Chroma Key Compositing
13. • RENDERING
– Rendering or image synthesis is the automatic process of generating a photorealistic or non-
photorealistic image from a 2D or 3D model (or models in what collectively could be called a scene file) by
means of computer programs. Also, the results of displaying such a model can be called a rendering.
– Though the technical details of rendering methods vary, the general challenges to overcome in producing
a 2D image from a 3D representation stored in a scene file are outlined as the graphics pipeline along a
rendering device, such as a GPU.
– A GPU is a purpose-built device able to assist a CPU in performing complex rendering calculations. If a
scene is to look relatively realistic and predictable under virtual lighting, the rendering software should
solve the rendering equation.
14. • RAY TRACING
– Ray tracing is a rendering technique for
generating an image by tracing the path
of light as pixels in an image plane and
simulating the effects of its encounters with
virtual objects. The technique is capable of
producing a very high degree of visual
realism, usually higher than that of
typical scanline rendering methods, but at a
greater computational cost
15. • SKELETAL ANIMATION
– Skeletal animation is a technique in computer
animation in which a character (or other articulated
object) is represented in two parts: a surface
representation used to draw the character
(called skin or mesh) and a hierarchical set of
interconnected bones (called the skeleton or rig) used to
animate (pose and keyframe) the mesh.
'Bones' (in green) used to pose a hand. In practice, the 'bones'
themselves are often hidden and replaced by more user-friendly
objects.
• MORPHING
– Morphing is a special
effect in motion
pictures and animations that
changes (or morphs) one image or
shape into another through a
seamless transition.
Three frames form a morph from George W. Bush
to Arnold Schwarzenegger showing the midpoint between
the two extremes.
16. • COMPOSITING
– Compositing is the combining of visual elements from separate
sources into single images, often to create the illusion that all
those elements are parts of the same scene. Live-action shooting
for compositing is variously called "chroma key", "blue screen",
"green screen" and other names.
– Today, most, though not all, compositing is achieved
through digital image manipulation. Pre-digital
compositing techniques, however, go back as far as the trick films
of Georges Méliès in the late 19th century, and some are still in
use.
• CHROMA KEY
– Chroma key compositing, or chroma keying, is a visual
effects / post-production technique for compositing (layering)
two images or video streams together based on color hues
(chroma range). The technique has been used heavily in many
fields to remove a background from the subject of a photo or
video – particularly the newscasting, motion
picture and videogame industries.
18. SOFTWARES USED FOR CGI
• - Photoshop: concept art/texturing/matte
painting
- Nuke: compositing/3D projections/small
particle set ups/roto/prep
- After effects: motion graphics/ compositing
(never saw it in feature film, but I know it is
used for commercials and TV productions)
- Maya:
modeling/animation/rigging/shading/skinnin
g/simulation/lighting/layout
- Houdini:
modeling/animation/rigging/shading/skinnin
g/simulation/lighting
- renderman: shading/lighting/rendering
-ZBrush: modeling/concept art/texturing/3D
sculpting/prototyping
- MudBox: modeling/concept
art/texturing/3D sculpting/prototyping
- Modo: Modeling/texturing
- Mari: texturing
- Realflow: simulation
- Arnold: rendering/shading/lighting
- clarisse: rendering/shading/lighting
20. CGI ANIMATION PROCESS
• CGI Animation is a complex process that takes several steps in order to go from a simple idea to a
complete animation. The steps for CGI animation are usually done by several people, with different
people working on each step.
• There are five major steps when it comes to CGI animation:
– Script
– Storyboard
– Layout
– Animation
– Final Revision
Each step requires careful planning and lots of work.
21. STEP 1 : SCRIPT
• The first step when making a CGI animation is
to make a script of the scene.
• This is a written list of all of the backgrounds,
characters, dialogue, and poses that are going
to be used in a scene, going in chronological
order.
• This step is pretty much the same as the script
step in other forms of media, such as films, TV
shows, and plays.
• Trying to animate a scene without a logical
plan isn’t a good idea, since the animators
won’t have a clear idea of what to animate.
• They will have to then come up with a story as
they animate, which can result in a sloppy,
unorganized mess. Coming up with a script for
the scene will help in the long run.
22. STEP 2 : STORYBOARD
• The next step in CGI Animation is the Storyboard
phase.
• A scene is drawn out in several 2D drawings, showing a
rough idea of the environments, characters, and
camera angles that you would see in the finished film.
• The script is usually shown at the bottom of each
drawing to show what is happening.
• In a big-budget CGI film, the animator pitches out the
storyboard to the other people in the animation crew.
• The professional voice-acting typically isn’t done at
this stage, so the animator usually does a rough
impression of each character while pitching out each
scene.
23. STEP 3 : LAYOUT
• The third step of CGI animation is the Layout step. Here, the characters and backgrounds for
the scene get rendered in 3D.
• Animators use computers to build a basic model of each 3D character in the scene. Animators
will usually use a reference source, such as a 2D drawing or clay sculpture, while creating the
3D model. Detailed features of a character, such as hair or lighting effects, aren’t created yet.
• Once the characters and backgrounds are made, it is time to begin the Layout step. Here,
characters are placed in the correct spots, and the camera angles for every frame are decided.
Then, a rough cut of the scene is played out in 3D. This is kind of like a 3D version of a
storyboard.
• This step give animators a basic idea of how the scene will look in 3D. After a screening of the
scene, some things may be altered and tweaked.
• Scenes can be omitted at this point, but it is a lot less common to cut a scene now than it is
during the storyboard phase. After getting the layouts done, it is time to begin the actual
animation of the scene.
25. STEP 4 : ANIMATION
• The next step is the Animation step. The basic
character models are now posed and moved to
their finalized movements. Everything from
mouth flaps to footsteps are created at this
stage.
• Similar to 2D animation, each frame is created
and then tweaked very slightly from one frame
to the next.
• When played in order, the individual frames
make a complete animation. It is important to
note that the more complex parts of a character
(such as facial hair) aren’t made yet, and the
lighting of the objects and characters aren’t
created yet.
• This is, essentially, a rough draft of an animation.
Nevertheless, finishing this step will have the
film completely animated.
26. STEP 5 : REVISION
• Once that is finished, it is time to move onto the Final
Revision step.
• Here, the more complicated parts of CGI, such as
hair, lighting, and textures, are placed onto the
animation.
• These complicated parts are saved for last since they
are typically the most difficult parts of CGI.
• Animating hair is very complicated, since there are
hundreds of thousands of unique hairs to keep track
of.
• They also have to be animated for effects such as
wind and movement. Full hair on a character was not
tried in a CGI film until Monsters, Inc. in 2001, when
Sully (one of the main characters) was animated with
a full coat of realistic fur.
28. Fractal Frame
FRACTALS
• “A fractal is a mathematical set that
typically displays self-similar patterns.”
• A fractal is an abstract object used to
describe and simulate naturally occurring
objects. Artificially created fractals
commonly exhibit similar patterns at
increasingly small scales. It is also known
as expanding symmetry or evolving
symmetry
• Generation Techniques :
– Iterated Function Systems
– Strange Attractors
– Escape-time fractal
29. Fractal Landscape
A fractal landscape is a surface generated using
a stochastic algorithm designed to
produce fractal behavior that mimics the
appearance of natural terrain. In other words,
the result of the procedure is not a
deterministic fractal surface, but rather a
random surface that exhibits fractal behavior.
32. ANATOMICAL MODELS
• Computer generated models.
• SCII developed anatomically
correct models.
• Used for instructional and
operational purposes.
A CT pulmonary angiogram image generated
by a computer from a collection of x-rays.
33. CLOTH IMAGERY
Models of cloth generally fall into three
groups:
• The geometric-mechanical structure
at yarn crossing
• The mechanics of continuous elastic
sheets
• The geometric macroscopic features of
cloth.
34. SKIN IMAGERY
The challenge in rendering human
skin images involves three levels of realism:
• Photo realism in resembling real skin at
the static level
• Physical realism in resembling its
movements
• Function realism in resembling its
response to actions.
35. USES OF CGI
• CGI is used in films, television programs
and commercials, and in printed media.
• Video games most often use real-time
computer graphics (rarely referred to as
CGI), but may also include pre-rendered
"cut scenes" and intro movies that
would be typical CGI applications.
• CGI is used for visual effects
• Animated Models in games
• Medical Imaging
• Realism in computer animation
• Computer-Aided Design for
engineering and architectural systems