<s>
GLOH	B-Algorithm
(	O
Gradient	O
Location	O
and	O
Orientation	O
Histogram	B-Algorithm
)	O
is	O
a	O
robust	O
image	B-General_Concept
descriptor	I-General_Concept
that	O
can	O
be	O
used	O
in	O
computer	B-Application
vision	I-Application
tasks	O
.	O
</s>
<s>
It	O
is	O
a	O
SIFT-like	O
descriptor	O
that	O
considers	O
more	O
spatial	O
regions	O
for	O
the	O
histograms	B-Algorithm
.	O
</s>
<s>
Principal	B-Application
components	I-Application
analysis	I-Application
(	O
PCA	O
)	O
is	O
then	O
used	O
to	O
reduce	O
the	O
vector	O
size	O
to	O
128	O
(	O
same	O
size	O
as	O
SIFT	O
descriptor	O
vector	O
)	O
.	O
</s>
