<s>
An	O
active	B-General_Concept
appearance	I-General_Concept
model	I-General_Concept
(	O
AAM	O
)	O
is	O
a	O
computer	B-Application
vision	I-Application
algorithm	O
for	O
matching	O
a	O
statistical	O
model	O
of	O
object	O
shape	O
and	O
appearance	O
to	O
a	O
new	O
image	O
.	O
</s>
<s>
A	O
set	O
of	O
images	O
,	O
together	O
with	O
coordinates	O
of	O
landmarks	B-General_Concept
that	O
appear	O
in	O
all	O
of	O
the	O
images	O
,	O
is	O
provided	O
to	O
the	O
training	O
supervisor	O
.	O
</s>
<s>
Cootes	O
,	O
Edwards	O
and	O
Taylor	O
further	O
described	O
the	O
approach	O
as	O
a	O
general	O
method	O
in	O
computer	B-Application
vision	I-Application
at	O
the	O
European	O
Conference	O
on	O
Computer	B-Application
Vision	I-Application
in	O
the	O
same	O
year	O
.	O
</s>
<s>
The	O
approach	O
is	O
widely	O
used	O
for	O
matching	B-Operating_System
and	I-Operating_System
tracking	I-Operating_System
faces	I-Operating_System
and	O
for	O
medical	B-Application
image	I-Application
interpretation	I-Application
.	O
</s>
<s>
By	O
taking	O
advantage	O
of	O
the	O
least	B-Algorithm
squares	I-Algorithm
techniques	O
,	O
it	O
can	O
match	O
to	O
new	O
images	O
very	O
swiftly	O
.	O
</s>
<s>
It	O
is	O
related	O
to	O
the	O
active	B-General_Concept
shape	I-General_Concept
model	I-General_Concept
(	O
ASM	O
)	O
.	O
</s>
<s>
One	O
disadvantage	O
of	O
ASM	O
is	O
that	O
it	O
only	O
uses	O
shape	O
constraints	O
(	O
together	O
with	O
some	O
information	O
about	O
the	O
image	O
structure	O
near	O
the	O
landmarks	B-General_Concept
)	O
,	O
and	O
does	O
not	O
take	O
advantage	O
of	O
all	O
the	O
available	O
information	O
–	O
the	O
texture	O
across	O
the	O
target	O
object	O
.	O
</s>
