<s>
Direct	B-General_Concept
linear	I-General_Concept
transformation	I-General_Concept
(	O
DLT	O
)	O
is	O
an	O
algorithm	O
which	O
solves	O
a	O
set	O
of	O
variables	O
from	O
a	O
set	O
of	O
similarity	O
relations	O
:	O
</s>
<s>
Practical	O
examples	O
include	O
the	O
relation	O
between	O
3D	O
points	O
in	O
a	O
scene	O
and	O
their	O
projection	O
onto	O
the	O
image	O
plane	O
of	O
a	O
pinhole	B-Algorithm
camera	I-Algorithm
,	O
and	O
homographies	B-Algorithm
.	O
</s>
<s>
What	O
makes	O
the	O
direct	B-General_Concept
linear	I-General_Concept
transformation	I-General_Concept
problem	O
distinct	O
from	O
the	O
above	O
standard	O
case	O
is	O
the	O
fact	O
that	O
the	O
left	O
and	O
right	O
sides	O
of	O
the	O
defining	O
equation	O
can	O
differ	O
by	O
an	O
unknown	O
multiplicative	O
factor	O
which	O
is	O
dependent	O
on	O
k	O
.	O
As	O
a	O
consequence	O
,	O
cannot	O
be	O
computed	O
as	O
in	O
the	O
standard	O
case	O
.	O
</s>
<s>
The	O
combination	O
of	O
rewriting	O
the	O
similarity	O
equations	O
as	O
homogeneous	O
linear	O
equations	O
and	O
solving	O
them	O
by	O
standard	O
methods	O
is	O
referred	O
to	O
as	O
a	O
direct	B-General_Concept
linear	I-General_Concept
transformation	I-General_Concept
algorithm	O
or	O
DLT	O
algorithm	O
.	O
</s>
