<s>
A	O
filter	B-Library
graph	I-Library
is	O
used	O
in	O
multimedia	O
processing	O
-	O
for	O
example	O
,	O
to	O
capture	O
video	O
from	O
a	O
webcam	B-Protocol
.	O
</s>
<s>
Filters	B-Application
take	O
input	O
,	O
process	O
it	O
(	O
or	O
change	O
the	O
input	O
)	O
,	O
and	O
then	O
output	O
the	O
processed	O
data	O
.	O
</s>
<s>
For	O
example	O
:	O
a	O
video	B-Application
codec	I-Application
takes	O
raw	O
uncompressed	B-Device
video	I-Device
and	O
compresses	O
it	O
using	O
a	O
video	O
standard	O
such	O
as	O
H.264	B-Application
.	O
</s>
<s>
To	O
compress	O
a	O
multimedia	O
stream	O
a	O
filter	B-Library
graph	I-Library
could	O
have	O
two	O
inputs	O
:	O
</s>
<s>
The	O
file	O
sources	O
would	O
feed	O
compression	O
filters	B-Application
,	O
the	O
output	O
of	O
the	O
compression	O
filters	B-Application
would	O
feed	O
into	O
a	O
multiplexer	B-Protocol
that	O
would	O
combine	O
the	O
two	O
inputs	O
and	O
produce	O
a	O
single	O
output	O
.	O
</s>
<s>
(	O
An	O
example	O
of	O
a	O
multiplexer	B-Protocol
would	O
be	O
an	O
MPEG	O
transport	O
stream	O
creator	O
.	O
)	O
</s>
<s>
Finally	O
the	O
multiplexer	B-Protocol
output	O
feeds	O
into	O
a	O
file	O
sink	B-Application
,	O
which	O
would	O
create	O
a	O
file	O
from	O
the	O
output	O
.	O
</s>
<s>
A	O
filter	B-Library
graph	I-Library
in	O
multimedia	O
processing	O
is	O
a	O
directed	O
graph	O
.	O
</s>
<s>
GStreamer	B-Language
-	O
Linux	O
based	O
multimedia	O
framework	O
.	O
</s>
<s>
In	O
Gstreamer	B-Language
a	O
filter	O
is	O
called	O
an	O
element	O
.	O
</s>
<s>
Filter	B-Library
graphs	I-Library
can	O
be	O
built	O
with	O
the	O
.	O
</s>
<s>
DirectShow	B-Library
-	O
Windows	O
based	O
multimedia	O
framework	O
.	O
</s>
<s>
-	O
a	O
free	O
tool	O
for	O
building	O
DirectShow	B-Library
filter	B-Library
graphs	I-Library
and	O
generating	O
C++	O
source	O
code	O
for	O
them	O
.	O
</s>
