<s>
A	O
separable	B-Algorithm
filter	I-Algorithm
in	O
image	B-Algorithm
processing	I-Algorithm
can	O
be	O
written	O
as	O
product	O
of	O
two	O
more	O
simple	O
filters	O
.	O
</s>
<s>
Typically	O
a	O
2-dimensional	O
convolution	B-Language
operation	O
is	O
separated	O
into	O
two	O
1-dimensional	O
filters	O
.	O
</s>
<s>
A	O
two-dimensional	O
smoothing	B-Application
filter	O
:	O
</s>
<s>
Another	O
two-dimensional	O
smoothing	B-Application
filter	O
with	O
stronger	O
weight	O
in	O
the	O
middle	O
:	O
</s>
<s>
The	O
Sobel	B-Algorithm
operator	I-Algorithm
,	O
used	O
commonly	O
for	O
edge	B-Algorithm
detection	I-Algorithm
:	O
</s>
<s>
This	O
works	O
also	O
for	O
the	O
Prewitt	B-Algorithm
operator	I-Algorithm
.	O
</s>
<s>
In	O
the	O
examples	O
,	O
there	O
is	O
a	O
cost	O
of	O
3	O
multiply	B-Algorithm
–	I-Algorithm
accumulate	I-Algorithm
operations	I-Algorithm
for	O
each	O
vector	O
which	O
gives	O
six	O
total	O
(	O
horizontal	O
and	O
vertical	O
)	O
.	O
</s>
