<s>
The	O
AIR	O
(	O
Automated	O
Image	B-Algorithm
Registration	I-Algorithm
)	O
is	O
a	O
program	O
suite	O
for	O
volume-based	O
image	B-Algorithm
registration	I-Algorithm
constructed	O
by	O
Roger	O
P	O
.	O
Woods	O
from	O
UCLA	O
School	O
of	O
Medicine	O
.	O
</s>
<s>
It	O
reads	O
and	O
writes	O
Analyze	O
volume	O
files	O
and	O
can	O
work	O
with	O
4x4	O
transformation	B-Algorithm
matrices	I-Algorithm
stored	O
in	O
its	O
own	O
file	O
format	O
with	O
the	O
filename	O
extension	O
.air	O
.	O
</s>
<s>
It	O
is	O
especially	O
designed	O
for	O
neuroimaging	B-Algorithm
applications	O
and	O
has	O
primarily	O
been	O
used	O
in	O
research-oriented	O
functional	B-Algorithm
neuroimaging	I-Algorithm
with	O
brain	B-Algorithm
scans	I-Algorithm
from	O
positron	B-Application
emission	I-Application
tomography	I-Application
and	O
magnetic	O
resonance	O
scanners	O
.	O
</s>
<s>
The	O
suite	O
provides	O
a	O
number	O
of	O
programs	O
for	O
image	B-Algorithm
registration	I-Algorithm
with	O
different	O
transformation	O
models	O
,	O
such	O
as	O
rigid-body	O
,	O
affine	O
and	O
nonlinear	O
warping	B-Algorithm
.	O
</s>
<s>
For	O
example	O
,	O
for	O
affine	O
transformation	O
the	O
registration	O
from	O
one	O
brain	B-Algorithm
scan	I-Algorithm
to	O
another	O
may	O
be	O
found	O
with	O
the	O
alignlinear	O
program	O
and	O
written	O
to	O
the	O
special	O
air-file	O
that	O
stores	O
the	O
transformation	B-Algorithm
matrix	I-Algorithm
.	O
</s>
