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Student Conference
on
Research and Development (SCOReD)
2003
Proceedings,
Putrajaya,
Malaysia
Keyframe
Animation
and
Motion
Capture for
Creating
Animation:
A
Survey
and
Perception
from
Industry
PeopIe
Mohd
Izani’,
Aishah’, hhmad
R%
Eshaq’
and
Norzaiha3
‘Facutty
of
Creative Multimedia, Multimedia University
63
100
Cyberjaya, Selangor, Malaysia
’Faculty
of
Creative Multimedia, Multimedia University
63
100
Cyberjaya, Selangor, Malaysia
3CMLC,
Multimedia University,
63
100
Cyberjaya,
Selangor, Malaysia
e-mail:
izani~~;,mniu.~dn.mv,
al~nia~lrali.cshaq(~~~~~~~i~~.~~~~~.mv,
norzaiha.norhan(i7!inn.etln.nlv
Abstract-
The history
of
animation is generally referred
to
early production of traditional animation. It has begun
in
the early
1900,
“Animalion
is
the
essence
of
animation
”
as explained by Halas
[I].
It
is
a
series
of
-
images that appear to be
in
motion. It can be either
traditional animation or computer animation.
In
addition
Greenberg
[23,
explains
“Animation
is
a
deliberately
interpreted “illusion
of
l$e.
”
If
110s
been
practiced
for
the
last
70~ears
in
both drawn
and
stop
motion
animnotion, and
as
such,
is
not
an attempt to mimic
kurnan
and
animal
l$e
exactly.”
Traditionally animation
is produced by drawing illusion of movement created by
photographing
a
series of individual drawings
on
successive frames on
film.
Gleicher
[3],
explains
“Animation is
a
uniquely
expressive art form:
it
provides the creator
with
conrrol over
both
the
appmrance
and
the
rirovcnienl
of
clzarricfers
and
objects.
This
gives
artists
tremendous
freedom.
which
when
well
used,
can
create
works
with
iremendous
impact.”
According to
the
historical timeline, many
forms
of
animation have been introduced. This
is
including cel animation, clay animation,
stop
frame
animation, three dimensional
(3D)
computer animation
and
virtual reality.
With
the rapid growth
of
this
industry various types
of
techniques, methodologies
and
computer technologies have been developed, for
instance keyframe
animation,
non-linear animation,
motion
capture,
procedural animation and etc.
This
research
will
discuss about producing animation by
using
two
methods; motion capture and keyframe
animation. Throughout this, the author will cover some
feedback
from
the respondents about the priority
of
using these both methods. It also will highlight the pros
and
cons
of
these
two
approaches.
Keywords
Keyframe animation, motion capture, traditional
animation, computer animation
I.
INTRODUCTION
Computer
Animation
went
through
so
much to
get
to
where it is at today.
It
still continues to change rapidly
today.
As
new, faster hardware and
more
sophisticated
software becomes available
at
continually
dropping
..
prices, new standards are appearing almost every
month.
This
research
will
highlight
two
methods of producing
computcr character animation; keyframe animation and
motion capture animation.
This
is
done
by
conducting
a
survey. The ultimate
goal
of this survey is to gain
response and collect
the
data for extensive analysis.
ln
order
to.collect
the data and response
from
the users or
correspondents, the
author
conducts a survey by
providing Internet based questionnaire.
A
set
of
questions, which consists
of
23
questions, has been
designed
to
ensure the collected data is more precise and
accurate. Finally the correspondents are required to
shareigive their experiencelopinion about the method
used in their projects. This is based
on
their prOfeSSi0nd
experiences and projects.
II.
COMPUTER
ANIMATION
Computer animation
has
been
around
as
Iong
as
computer graphics. Images convey a lot of information
because the human
visual
system
is
a
sophisticated
information processor. It follows, then, that moving
images
have the potcntial
to
convey much
more
information. When animation
is
recorded
for
later
viewing, it
is
typically presented in
film
or
video
formats
by
recording
a
series
of
still
images
[4].
This
is
possible because the eye-brain assembles
a
sequence
of
images and interprets
them
as a continuous movement.
Persistence
of
motion
is created
by
presenting
a
sequence
of
still images
at
a fast enough rate
to
induce
the
sensatim
of
continuous motion. This research
emphasizes computer character animation
as
its
main
point. Currently there are three main methods by which
a computer animation of
a
character can be generated
[5].
Most commonly, keyframing is
used,
in which the
animator specifies important key
poses
for
the character
at some
frames,
and the computer calculates what the
frames between thcse keys should
be
with
an
interpolation technique. Tn
a
second
method, physical
simulation
is
used
to drive
the
motion
of
the
character.
Due to the complexity
of
the required calculations, this
method
has not been used with much success for
characters. Finally,
in
more recent years, motion capture
has been used
to
animate
characters.
In
motion capture,
sensors are placed on a live person, and the data that
0-7803-8173-4/03/$17.00
02003
EEE.
154
describes his
or
her motion
is
collected and mapped
onto
the
character.
A.
Keyframe
Animation
The industry
of
computer animation has changed the
look
of
television, feature
films
and video. Street
[6]
explains, "The industry
of
computer animation is only
twenty five years old.
1x1
that time, artist and scientist
have moved from rudimentary 'flying
Iogos
to the
seemingly human move-characters.''
It
has
grown
since
long time ago
from
a highly experimental work done by
the
scientists and engineers. Nowadays,
with
the
increasing ability
to
produce computer animation at an
acceptable cost
and
speed,. the
role
of
computer
animation is
not
only
limited to the entertainment.
It
is
widely
used
for
web contents, architectural simulation,
virtual
reality, flight simulation, military, medical,
gaming industry and archaeology. Computer animation
can be achieved
in
many ways such as.scripting
systems, keyframing, behavioural animation and
procedural animatio?
Keyframing is one
of
the
methods
to
produce animation,
it
is
the main concept
of
computer animation.
Mealing
[7]
describes,
''
A
more complicated motion
can
usually
be decomposed into shorter sections, between the
extremes
of
which,
further
positions can be interpolated.
This
incremental change from one keyframe
to
another
is
known
as
'in-betweening'(Figure
1).
..
Fig.
1.
Sample
of
keyframe animation
progress
B.
Motion
Capture
Animation
The
use
of
motion capture.
for
computer
character
animation is relatively new, having
begun
in the late
1970's,
and only now beginning to become widespread.
Motion
capwe
is
the
recording of human body
movement
(or
other movement)
for
immediate or
delayed analysis and playback, The information
captured can be as general as
the
simple position
of
the
body in space
or
as complex as
the
deformations of the
face and muscle
masses
[SI.
Motion capture for
computer character aninlation involves
the
mapping
of
human
motion
onto
the
motion
of
a
computer character.
The mapping can be direct, such
as
human
arm
motion
controlling
a
character's
arm
motion,
or
indirect, such as
human
hand and
finger
patterns controlling a character's
skin
color
or emotional state.
As
described
by
Crow
[9],
"Morion
capture
for
animation
has
a
long,
fascinating,
..
..a
but
ponrlv
docurnented
history.
"
It was first used
in
the
late
70's
and early
SO'S
at school like Simon Fraser
Univcrsity,
Massachusetts
Institute
of
Technology
and
New
York Institute
of
Technology, the main purpose is
mainly
for
research Droiects. In the middle
of
go's,
it
was
Fig.
2.
Magnetic and optical motion capture system,
image courtesy
of
Metamotion
111.
SURVEY
There are
23
questions
for
this
survey, however
only
the
most
important
points will be enclosed for the feedback.
There are
100
respondents have participated
and
given
their response.
Below
are
the
feedback gained.
1
Bar Chart
I.
What is
your
background?
,
155
5
Bar
Chart
2.
Are
you
involved in
any
animation
movies
production?
3)
I
Bar
Chart
3.
Please
tick
the
number of
movies
involved.
4)
Ywmdn
inWest
io
mrFrder
g;pH5
Bar
Chart
4.
Your
main
interest
in
computer graphics.
Bar Chart
5.
Are
you
concerned
about
character
movement/perfarmance
in
any
3d/2d/cgi
animated
movies?
Bar
Chart
6.
In
the
future,
would
you
like
to
see
more
animation
movies/
games
in the market?
7)
Bar Chart
7.
Which one have
you
experienced?
156
Bar
Chart
8.
Which
one
have
you
used
most?
Bar
Chart
9,
Which
one
you
appreciatelprefer
most?
.,
..
,-
IO)
Bar
Chart
10.
Which
one is more economical?
Bar
Chart
1
1.
Which
one
is
faster
in
producing
anima
tion?
Bar
Chart
12.
Which
can
create
more
realistic
movement?
Ear
Chart
13.
Which process
is
more
complicated
and
tedious?
.
t-
157
Bar Chart
14.
In what level do you categorize yourself
in
this
field (motion capture)?
15)
Bar Chart
15.
Finally,
do
you agree that motion capture
is
good
for
human movement and not
for
cartoony/
exaggerated movement?
IV.
RESULTS
SUMMARY
To
sum
up
this
survey the author would like
to
state
a
few
important
notes that derived from the respondents’
feedback.
1)
Motion
capture and keyframe animation have their
place. From the
survey
and readings done
motion
capture
daki
need
to
be refined by keyframe
method.
Motion capture cannot stand alone without
manual keLframe -refinement. Most
of
the
respondents
ag;eed
that motion capture
is
good if
user
want
to capture -realistic’ movement and it is
also agreed that keyf?arne animation allow user to
create characters
with
more
life
and
utilise
traditional animation techniques (examples:
anticipation, squash, stretch etc.).
Usually,
to
operate
motion
capture session three
actordoperators are needed to bring
to
life; motion
capture actodpuppeteer,
clean
up
animator and
voice actor, while keyframe animator can adjust
every part
of
the
animation based on the dialogue
track. Inarguably for human motion, motion capture
is
the
best
solution
but
in certain circunlstances
motion capture process can
be
slow and laborious
compared to keyframe animation. Animators need
to
go
in and clean
up
captured data.
One
also
has
to
remember that
motion
capture is about
yuppeteering
not
animating,
the
process
of
*!<
animation comes in at the
end
when the data is
cleaned up and fixed.
Motion capture is believed will never replace
keyframe animation. In motion capture keyframe
will
be
B
secondary step for refinement of the
caphued
data.
For long-term use
motion
capture is
considered
as
economical method because
the
pipeline will
be
established and
the
reusability
of
motion libraries.
It is believable that
motion
capture is faster than
keyframe animation, initialIy it is not, it will
actually add time to pipeline especially when the
task need
an
integration with keyframe animation,
this
will
produce
a
massive volume
of
animation
than keyframing ever will.
Motion capture
is
not
easy
to
operate. It is a
specialisation in
itself
and
requires highly skilled
professionals to handle it.
In
term
of
consistency, users do not have problem
especially when every scene being animated
differently
for
the same character. Using one actor
for one character, it will consistently through a
project. And the captured data can be reusable. It
has
ability
to
store movement and
reuse
it
in
the
future characters.
.
‘
Accessibility is another issue, which
not
all
of the
people have access
to
it. Motion capture
is
a fast
way
to
give
realistic
movement
but
keyframing
is
more
economical. By keyframing,
animators
will
understand more deeply
about
basic animation
principles IiRe timing, anticipation and
so
on.
V.
CONCLUSIONS
conclude this
discussion,
the author notices that
motion capture would be fully useful if certain
proceduredstudies taken before
proceed
to
use
this
method,
the
criterion listed are as below:
Cost:
Is
it
worth
to invest?
Purpose
of
using
this
method:
Is
it for
smal1
scale
or large scale production.
Expertise/professionals in using the
facilities:
How good is the manpower behind
its
selection.
Pipeline
for
real
production
industry: The system
need
to
be properly
set
up
for
in house use.
Period
of
using: long term
or
short
term.
Potentiality:
Is
the facilities can be
fully
utilised to
earn profit by offering service
or
only for in house
production.
Problems
that
may
arise:
For the first timer in
approaching
this
method
may
face
a
lot
of troubles
and difficulties. The time spent for try and
experiment is
very
crucial and precious for a real
’
158
production because ;eal-indu+y
is
about time and
money.’
8)
Limitation:
Limitation
of
motion capture must also
be
considered,
myths
said
that
motion capture is
easy and fast
to
produce animation,
this
is
not
true
referring
to
experienced users feedback, unless
the
pipeline’
and
system
are
already established
and
frequently
used.
’
I.‘
‘
.
.-
..
VI.
REFERENCES
[I]
J.
Halas, Contemporary Animator, Boston: Focal
Press Publishing,
199
1
[2]
G.
Camer0q.A.
Bustanoby,
K.
Cope,
S.
Greenberg,
C.
Hayes,
0.
Ozoux
“Motion capture
and
CG
character
animation”,
Proceedings
of
the
24th
annual conference
on
Computer graphics and
interactive techniques, Siggraph 97
Vol.
24
pp.442
[3]
M.
Gleicher, “Animation From Observation:
Motion Capture and Motion Editing”, Proceedings
of
ACM
SIGGRAPII
Computer Graphics
33,
pp.51
[4]
Introduction
.
to,
Computer Animation,
.
state.edu/-parent/booWlntr.h&l#
Perception
-
445,1997.
-
54,1999.
.
..
http://www.cis.ohio-
[5]
K.A.
Pullen,
Motion capture assisted animation:
Texturing
and sysnthesis.
The
degree
of
Doctor
of
Philosophy
Dissertation,
Stanford
University,
2002.
[6]
S.
Mealig,‘
The
Art-.and
Sciknce
of
Computer
Animation, Cromland,
1995.‘
.
’
[7]
’
R.
Street, Comput& Animation:.
.A
Whole
New
World.
Rockport
Publishers, 1998.
[SI
S.J..
David,
“A
Brief
History
of
Motion Capture
for
Computer’
Character
Animation”,
Proceedings
of
ACM
SIGGRAPH
Computer.
Graphics,
Course
9,1994.
”-
.
[9]
F.
Crow.
Personal Communication, 1999.
.
..
..
r.
159
