Computer-generated imagery

Computer-generated imagery (CGI) is the
application of the field of computer graphics (or
more specifically, 3D computer graphics) to
special effects.
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 because the quality
is often higher and effects are more controllable
than other more physically based processes, such
as constructing miniatures for effects shots or
hiring extras for crowd scenes, and because it
allows the creation of images that would not be
feasible using any other technology.
It can also allow a single artist to produce
content without the use of actors, expensive set
pieces, or props.
Recent accessibility of CGI software and
increased computer speeds has allowed individual
artists and small companies to produce
professional grade films, games, and fine art from
their home computers.

Have you ever found yourself
sitting in the theater, watching a
Pixar film, and contemplating
what it is about CGI animation
that makes for some of the best
children’s movies?
The evolution of this field of
graphic design didn’t happen
over a very long, extended period
– but instead over a couple of
decades. In fact, the rapid
advancement of computer
processing power is primarily
what served as a catalyst for the
explosion of CGI animation. But
what is CGI animation, exactly?
If you’re a computer graphic
design artist, this post may not
be for you. However, for those of
you out there who are curious
about this fascinating form of
animation – read on for a brief
history of the world of animation,
and how computers completely
transformed the art form.
What Ever Happened to Plain Old
Cartoons?
Most of you can likely name at
least one or two of your favorite
childhood cartoons. Maybe it was
Scooby Doo, the Flintstones or
even the Jetsons. Maybe you’re a
bit younger (or not) and you still
enjoy your Saturday morning
cartoons.
However, most of the older folks
out there probably started
noticing that more and more
cartoons look just a little bit
different – just a little bit more
real . What is it about CGI
animation that gives the
characters and the overall
imagery more realism? The
answer to that requires some
history.
The history of animation is both
nostalgic and sad. Many decades
ago, animators were traditional
artists who drew pictures by
hand. Traditional animation
consisted of a whole team of
animators who would draw and
color images on “cels” –
transparent sheets that were
placed on top of a background
image to create a multi-layered
frame.
In this way, segments of an
image could change from frame
to frame without the entire
picture being redrawn. You can
see an example of layers in the
image to the left. The blue arrow
points to the background, the
green arrow to the layer with two
characters, and a red arrow
pointing to the third layer with an
image of a flying paper airplane.
By manipulating the drawings in
each layer from frame to frame,
animators would create what
many adults today remember as
the traditional cartoon.
Many movie fans may remember
the hype surrounding the digital
remastering of old films such as
Star Wars , where computer
animation was used to digitally
enhance the film. The first stages
of CGI animation included 2D
animation. This simply involved
computers doing what animators
had been doing for decades –
creating multiple frames of
images each second in order to
generate the visual effect of
animation.
The difference in this case was
that as the field of computer
graphic design advanced, the
images gradually became much
more advanced than most
cartoon animators could manage
by hand. The simplest form of
this type of animation can be
seen in the animated GIF files
that became wildly popular on
the Internet throughout the late
1990’s.
These images were created by
packaging together a series of
static images switched from
frame to frame by a time delay
defined by a control script within
the GIF file itself. The time delay
on most animated GIFS are
pretty long, so it doesn’t provide
for very fluid motion, but the
concept of “animation” is still
there.
The picture below is an example
of one such completed animated
GIF.
Now, all of this is grade school
level compared to the impressive
level that 3D CGI animation
technology is at today. How did
we get from 1990’s computer
animation to the sort of iMax 3D
cartoons you love to watch? The
simple answer is processing
power. With today’s amazing
CPU processing capabilities,
computer animators are now able
to create a 3 dimensional “model”
to start with.
This model is only somewhat like
it’s 2D counterpart, except now
computers have the ability to not
only modify large parts of a 2
dimensional image as “layers” –
they can calculate and modify
very small sections of an object
within a 3D world. Because of the
level of programming and
processor power required, this
sort of animation was available
only to the largest movie
production companies who could
afford the computer systems.
However, today your own
desktop computer can handle it –
and there’s even free software
like Blender , which Aibek covered
in his article on 4 apps for a
graphic designer on a budget ,
and Simon described one of the
video games called Yo Frankie!
which was created with the
Blender engine. I installed the
software on my own desktop and
within 30 minutes the tutorial
taught me how to create the
start of a snowman character
within a virtual 3D world.
The concept of today’s level of
3D CGI animation is an evolution
from basic cartoon animation
into a simulated world that seeks
to represent realism as
accurately as possible. It does
this by slicing up the world into
the smallest segments possible,
and then controlling how those
tiny parts of real world objects
move, react and change based on
the other objects and conditions
within that 3D world.
I remember watching The Polar
Express when it was first
released and thinking to myself
how dead the characters looked.
When they spoke, their tongues
lay still like dead fish and their
eyes were often expressionless. I
actually thought, at the time, that
computers would never be able
to realistically simulate the real
world, or at least a real person.
But, you know what, while
researching this article I came
across this video of “Emily,” a
digitally recreated face of a real
actress. I have to say, I was very
impressed and I think you will be
as well.
What is your take on the current
state of the art for CGI
animation? Do you think that it
will eventually completely replace
traditional animation? Share your
opinion in the comments section
below.