<s>
ANIMAL	O
(	O
first	O
implementation	O
:	O
1988	O
-	O
revised	O
:	O
2004	O
)	O
is	O
an	O
interactive	O
environment	O
for	O
image	B-Algorithm
processing	I-Algorithm
that	O
is	O
oriented	O
toward	O
the	O
rapid	O
prototyping	O
,	O
testing	O
,	O
and	O
modification	O
of	O
algorithms	O
.	O
</s>
<s>
To	O
create	O
ANIMAL	O
(	O
AN	O
IMage	O
ALgebra	O
)	O
,	O
XLISP	B-Language
of	O
David	O
Betz	O
was	O
extended	O
with	O
some	O
new	O
types	O
:	O
sockets	O
,	O
arrays	O
,	O
images	O
,	O
masks	O
,	O
and	O
drawables	O
.	O
</s>
<s>
In	O
the	O
theoretical	O
framework	O
of	O
ANIMAL	O
a	O
digital	B-Algorithm
image	I-Algorithm
is	O
a	O
boundless	O
matrix	O
with	O
its	O
history	O
.	O
</s>
<s>
In	O
this	O
way	O
all	O
the	O
pixels	B-Algorithm
,	O
including	O
those	O
on	O
the	O
border	O
,	O
have	O
the	O
same	O
number	O
of	O
neighbors	O
(	O
useful	O
in	O
local	O
operators	O
,	O
such	O
as	O
digital	O
filters	O
)	O
.	O
</s>
<s>
ANIMAL	O
has	O
been	O
ported	O
to	O
R	B-Language
,	O
a	O
freely	O
available	O
language	O
and	O
environment	O
for	O
statistical	O
computing	O
and	O
graphics	O
.	O
</s>
