<s>
An	O
event	B-Algorithm
camera	I-Algorithm
,	O
also	O
known	O
as	O
a	O
neuromorphic	O
camera	O
,	O
silicon	B-Algorithm
retina	I-Algorithm
or	O
dynamic	B-Algorithm
vision	I-Algorithm
sensor	I-Algorithm
,	O
is	O
an	O
imaging	B-Algorithm
sensor	I-Algorithm
that	O
responds	O
to	O
local	O
changes	O
in	O
brightness	O
.	O
</s>
<s>
Event	B-Algorithm
cameras	I-Algorithm
do	O
not	O
capture	O
images	O
using	O
a	O
shutter	O
as	O
conventional	O
(	O
frame	O
)	O
cameras	O
do	O
.	O
</s>
<s>
Instead	O
,	O
each	O
pixel	O
inside	O
an	O
event	B-Algorithm
camera	I-Algorithm
operates	O
independently	O
and	O
asynchronously	O
,	O
reporting	O
changes	O
in	O
brightness	O
as	O
they	O
occur	O
,	O
and	O
staying	O
silent	O
otherwise	O
.	O
</s>
<s>
Event	B-Algorithm
camera	I-Algorithm
pixels	O
independently	O
respond	O
to	O
changes	O
in	O
brightness	O
as	O
they	O
occur	O
.	O
</s>
<s>
Thus	O
,	O
event	B-Algorithm
cameras	I-Algorithm
output	O
an	O
asynchronous	O
stream	O
of	O
events	O
triggered	O
by	O
changes	O
in	O
scene	O
illumination.Event	O
cameras	O
have	O
microsecond	O
temporal	O
resolution	O
,	O
120dB	O
dynamic	O
range	O
,	O
and	O
less	O
under/overexposure	O
and	O
motion	O
blur	O
than	O
frame	O
cameras	O
.	O
</s>
<s>
Because	O
individual	O
pixels	O
fire	O
independently	O
,	O
event	B-Algorithm
cameras	I-Algorithm
appear	O
suitable	O
for	O
integration	O
with	O
asynchronous	O
computing	O
architectures	O
such	O
as	O
neuromorphic	O
computing	O
.	O
</s>
<s>
*	O
Indicates	O
temporal	O
resolution	O
since	O
human	O
eyes	O
and	O
event	B-Algorithm
cameras	I-Algorithm
do	O
not	O
output	O
frames	O
.	O
</s>
<s>
Temporal	O
contrast	O
sensors	O
(	O
such	O
as	O
DVS	O
(	O
Dynamic	B-Algorithm
Vision	I-Algorithm
Sensor	I-Algorithm
)	O
or	O
sDVS	O
(	O
sensitive-DVS	O
)	O
)	O
produce	O
events	O
that	O
indicate	O
polarity	O
(	O
increase	O
or	O
decrease	O
in	O
brightness	O
)	O
,	O
while	O
temporal	O
image	B-Algorithm
sensors	I-Algorithm
indicate	O
the	O
instantaneous	O
intensity	O
with	O
each	O
event	O
.	O
</s>
<s>
The	O
DAVIS	O
(	O
Dynamic	O
and	O
Active-pixel	O
Vision	O
Sensor	O
)	O
contains	O
a	O
global	O
shutter	O
active	B-Architecture
pixel	I-Architecture
sensor	I-Architecture
(	O
APS	O
)	O
in	O
addition	O
to	O
the	O
dynamic	B-Algorithm
vision	I-Algorithm
sensor	I-Algorithm
(	O
DVS	O
)	O
that	O
shares	O
the	O
same	O
photosensor	O
array	O
.	O
</s>
<s>
Many	O
event	B-Algorithm
cameras	I-Algorithm
additionally	O
carry	O
an	O
inertial	O
measurement	O
unit	O
(	O
IMU	O
)	O
.	O
</s>
<s>
Another	O
class	O
of	O
event	O
sensors	O
are	O
so-called	O
retinomorphic	B-Algorithm
sensors	I-Algorithm
.	O
</s>
<s>
They	O
can	O
hence	O
be	O
considered	O
a	O
single	O
device	O
that	O
produces	O
the	O
same	O
result	O
as	O
a	O
small	O
circuit	O
in	O
other	O
event	B-Algorithm
cameras	I-Algorithm
.	O
</s>
<s>
Retinomorphic	B-Algorithm
sensors	I-Algorithm
have	O
to-date	O
only	O
been	O
studied	O
in	O
a	O
research	O
environment	O
.	O
</s>
<s>
Alternative	O
methods	O
include	O
optimization	O
and	O
gradient	O
estimation	O
followed	O
by	O
Poisson	B-Algorithm
integration	I-Algorithm
.	O
</s>
<s>
The	O
concept	O
of	O
spatial	O
event-driven	O
convolution	B-Language
was	O
postulated	O
in	O
1999	O
(	O
before	O
the	O
DVS	O
)	O
,	O
but	O
later	O
generalized	O
during	O
EU	O
project	O
CAVIAR	O
(	O
during	O
which	O
the	O
DVS	O
was	O
invented	O
)	O
by	O
projecting	O
event-by-event	O
an	O
arbitrary	O
convolution	B-Language
kernel	I-Language
around	O
the	O
event	O
coordinate	O
in	O
an	O
array	O
of	O
integrate-and-fire	O
pixels	O
.	O
</s>
<s>
Extension	O
to	O
multi-kernel	O
event-driven	O
convolutions	B-Language
allows	O
for	O
event-driven	O
deep	B-Architecture
convolutional	I-Architecture
neural	I-Architecture
networks	I-Architecture
.	O
</s>
<s>
Segmentation	B-Algorithm
and	O
detection	B-Algorithm
of	I-Algorithm
moving	I-Algorithm
objects	I-Algorithm
viewed	O
by	O
an	O
event	B-Algorithm
camera	I-Algorithm
can	O
seem	O
to	O
be	O
a	O
trivial	O
task	O
,	O
as	O
it	O
is	O
done	O
by	O
the	O
sensor	O
on-chip	O
.	O
</s>
<s>
Some	O
of	O
the	O
recent	O
approaches	O
to	O
solving	O
this	O
problem	O
include	O
the	O
incorporation	O
of	O
motion-compensation	O
models	O
and	O
traditional	O
clustering	B-Algorithm
algorithms	I-Algorithm
.	O
</s>
<s>
The	O
US	O
military	O
is	O
considering	O
infrared	O
and	O
other	O
event	B-Algorithm
cameras	I-Algorithm
because	O
of	O
their	O
lower	O
power	O
consumption	O
and	O
reduced	O
heat	O
generation	O
.	O
</s>
