<s>
A	O
frame	B-Device
grabber	I-Device
is	O
an	O
electronic	O
device	O
that	O
captures	O
(	O
i.e.	O
,	O
"	O
grabs	O
"	O
)	O
individual	O
,	O
digital	O
still	O
frames	O
from	O
an	O
analog	O
video	O
signal	O
or	O
a	O
digital	O
video	O
stream	O
.	O
</s>
<s>
It	O
is	O
usually	O
employed	O
as	O
a	O
component	O
of	O
a	O
computer	B-Application
vision	I-Application
system	O
,	O
in	O
which	O
video	O
frames	O
are	O
captured	O
in	O
digital	O
form	O
and	O
then	O
displayed	O
,	O
stored	O
,	O
transmitted	O
,	O
analyzed	O
,	O
or	O
combinations	O
of	O
these	O
.	O
</s>
<s>
Historically	O
,	O
frame	B-Device
grabber	I-Device
expansion	B-Device
cards	I-Device
were	O
the	O
predominant	O
way	O
to	O
interface	O
cameras	O
to	O
PCs	O
.	O
</s>
<s>
Other	O
interface	O
methods	O
have	O
emerged	O
since	O
then	O
,	O
with	O
frame	B-Device
grabbers	I-Device
(	O
and	O
in	O
some	O
cases	O
,	O
cameras	O
with	O
built-in	O
frame	B-Device
grabbers	I-Device
)	O
connecting	O
to	O
computers	O
via	O
interfaces	O
such	O
as	O
USB	B-Protocol
,	O
Ethernet	O
and	O
IEEE	O
1394	O
(	O
"	O
FireWire	O
"	O
)	O
.	O
</s>
<s>
Early	O
frame	B-Device
grabbers	I-Device
typically	O
had	O
only	O
enough	O
memory	B-General_Concept
to	O
store	O
a	O
single	O
digitized	O
video	O
frame	O
,	O
whereas	O
many	O
modern	O
frame	B-Device
grabbers	I-Device
can	O
store	O
multiple	O
frames	O
.	O
</s>
<s>
Modern	O
frame	B-Device
grabbers	I-Device
often	O
are	O
able	O
to	O
perform	O
functions	O
beyond	O
capturing	O
a	O
single	O
video	O
input	O
.	O
</s>
<s>
Other	O
operations	O
may	O
be	O
performed	O
as	O
well	O
,	O
such	O
as	O
deinterlacing	O
,	O
text	O
or	O
graphics	O
overlay	B-Architecture
,	O
image	O
transformations	O
(	O
e.g.	O
,	O
resizing	O
,	O
rotation	O
,	O
mirroring	O
)	O
,	O
and	O
conversion	O
to	O
JPEG	O
or	O
other	O
compressed	O
image	O
formats	O
.	O
</s>
<s>
To	O
satisfy	O
the	O
technological	O
demands	O
of	O
applications	O
such	O
as	O
radar	B-Application
acquisition	I-Application
,	O
manufacturing	O
and	O
remote	B-Application
guidance	I-Application
,	O
some	O
frame	B-Device
grabbers	I-Device
can	O
capture	O
images	O
at	O
high	O
frame	O
rates	O
,	O
high	O
resolutions	O
,	O
or	O
both	O
.	O
</s>
<s>
Analog	O
frame	B-Device
grabbers	I-Device
,	O
which	O
accept	O
and	O
process	O
analog	O
video	O
signals	O
,	O
include	O
these	O
circuits	O
:	O
</s>
<s>
Digital	O
frame	B-Device
grabbers	I-Device
,	O
which	O
accept	O
and	O
process	O
digital	O
video	O
streams	O
,	O
include	O
these	O
circuits	O
:	O
</s>
<s>
Circuitry	O
common	O
to	O
both	O
analog	O
and	O
digital	O
frame	B-Device
grabbers	I-Device
:	O
</s>
<s>
Frame	B-Device
grabbers	I-Device
are	O
used	O
in	O
medicine	O
for	O
many	O
applications	O
,	O
including	O
telenursing	O
and	O
remote	B-Application
guidance	I-Application
.	O
</s>
<s>
In	O
situations	O
where	O
an	O
expert	O
at	O
another	O
location	O
needs	O
to	O
be	O
consulted	O
,	O
frame	B-Device
grabbers	I-Device
capture	O
the	O
image	O
or	O
video	O
from	O
the	O
appropriate	O
medical	O
equipment	O
,	O
so	O
it	O
can	O
be	O
sent	O
digitally	O
to	O
the	O
distant	O
expert	O
.	O
</s>
<s>
Each	O
camera	O
is	O
paired	O
with	O
a	O
frame	B-Device
grabber	I-Device
that	O
digitizes	O
the	O
analog	O
video	O
,	O
thus	O
converting	O
the	O
video	O
to	O
a	O
form	O
that	O
can	O
be	O
processed	O
by	O
the	O
machine	O
software	O
.	O
</s>
<s>
Frame	B-Device
grabbers	I-Device
may	O
be	O
used	O
in	O
security	O
applications	O
.	O
</s>
<s>
For	O
example	O
,	O
when	O
a	O
potential	O
breach	O
of	O
security	O
is	O
detected	O
,	O
a	O
frame	B-Device
grabber	I-Device
captures	O
an	O
image	O
or	O
a	O
sequence	O
of	O
images	O
,	O
and	O
then	O
the	O
images	O
are	O
transmitted	O
across	O
a	O
digital	O
network	O
where	O
they	O
are	O
recorded	O
and	O
viewed	O
by	O
security	O
personnel	O
.	O
</s>
<s>
Frame	B-Device
grabbing	I-Device
is	O
becoming	O
very	O
popular	O
on	O
these	O
devices	O
.	O
</s>
<s>
Amateur	O
astronomers	O
and	O
astrophotographers	O
use	O
frame	B-Device
grabbers	I-Device
when	O
using	O
analog	O
"	O
low	O
light	O
"	O
cameras	O
for	O
live	O
image	O
display	O
and	O
internet	O
video	O
broadcasting	O
of	O
celestial	O
objects	O
.	O
</s>
<s>
Frame	B-Device
grabbers	I-Device
are	O
essential	O
to	O
connect	O
the	O
analog	O
cameras	O
used	O
in	O
this	O
application	O
to	O
the	O
computers	O
that	O
store	O
or	O
process	O
the	O
images	O
.	O
</s>
