<s>
Musipedia	B-Application
is	O
a	O
search	B-Application
engine	I-Application
for	O
identifying	O
pieces	O
of	O
music	O
.	O
</s>
<s>
Anybody	O
can	O
modify	O
the	O
collection	O
of	O
melodies	O
and	O
enter	O
MIDI	O
files	O
,	O
bitmaps	O
with	O
sheet	O
music	O
(	O
possibly	O
generated	O
by	O
the	O
Musipedia	B-Application
server	O
after	O
entering	O
LilyPond	B-Application
or	O
abc	O
source	O
code	O
)	O
,	O
lyrics	O
or	O
some	O
text	O
about	O
the	O
piece	O
,	O
or	O
the	O
melodic	O
contours	O
as	O
Parsons	O
Code	O
.	O
</s>
<s>
Musipedia	B-Application
offers	O
three	O
ways	O
of	O
searching	O
:	O
Based	O
on	O
the	O
melodic	O
contour	O
,	O
based	O
on	O
pitches	O
and	O
onset	O
times	O
,	O
or	O
based	O
on	O
the	O
rhythm	O
alone	O
.	O
</s>
<s>
Because	O
of	O
this	O
,	O
the	O
search	B-Application
engine	I-Application
finds	O
not	O
only	O
entries	O
with	O
exactly	O
the	O
contour	O
that	O
is	O
entered	O
as	O
a	O
query	O
,	O
but	O
also	O
the	O
most	O
similar	O
ones	O
among	O
the	O
contours	O
that	O
are	O
not	O
identical	O
.	O
</s>
<s>
The	O
melody	O
can	O
be	O
entered	O
in	O
various	O
ways	O
,	O
for	O
example	O
by	O
clicking	O
on	O
a	O
virtual	B-Device
keyboard	I-Device
on	O
the	O
screen	O
.	O
</s>
<s>
The	O
search	B-Application
engine	I-Application
then	O
segments	O
the	O
query	O
,	O
converts	O
each	O
segment	O
into	O
a	O
set	O
of	O
points	O
in	O
the	O
two-dimensional	O
space	O
of	O
onset	O
time	O
and	O
pitch	O
,	O
and	O
,	O
by	O
using	O
the	O
Earth	O
Mover	O
's	O
Distance	O
,	O
compares	O
each	O
point	O
set	O
to	O
pre-computed	O
point	O
sets	O
representing	O
segments	O
of	O
melodies	O
from	O
the	O
database	O
.	O
</s>
<s>
Instead	O
of	O
calculating	O
the	O
distance	O
between	O
the	O
query	O
and	O
every	O
single	O
database	O
entry	O
,	O
Musipedia	B-Application
just	O
calculates	O
the	O
distance	O
between	O
the	O
query	O
and	O
each	O
of	O
a	O
few	O
vantage	O
objects	O
.	O
</s>
<s>
Since	O
the	O
triangle	O
inequality	O
holds	O
for	O
both	O
the	O
editing	O
distance	O
for	O
contours	O
and	O
the	O
variant	O
of	O
the	O
Earth	O
Mover	O
's	O
Distance	O
used	O
by	O
Musipedia	B-Application
,	O
the	O
search	O
algorithm	O
needs	O
,	O
in	O
a	O
second	O
step	O
,	O
to	O
take	O
a	O
closer	O
look	O
at	O
only	O
those	O
database	O
entries	O
whose	O
distances	O
to	O
the	O
vantage	O
objects	O
are	O
similar	O
to	O
the	O
distances	O
between	O
the	O
query	O
and	O
the	O
vantage	O
objects	O
.	O
</s>
<s>
Musipedia	B-Application
's	O
search	B-Application
engine	I-Application
works	O
differently	O
from	O
that	O
of	O
search	B-Application
engines	I-Application
such	O
as	O
Shazam	B-Application
.	O
</s>
<s>
Shazam	B-Application
uses	O
Audio	B-Algorithm
Fingerprinting	I-Algorithm
for	O
that	O
,	O
a	O
technique	O
that	O
makes	O
it	O
possible	O
to	O
identify	O
recordings	O
.	O
</s>
<s>
Musipedia	B-Application
,	O
on	O
the	O
other	O
hand	O
,	O
can	O
identify	O
pieces	O
of	O
music	O
that	O
contain	O
a	O
given	O
melody	O
.	O
</s>
<s>
Shazam	B-Application
finds	O
exactly	O
the	O
recording	O
that	O
contains	O
a	O
given	O
snippet	O
,	O
but	O
no	O
other	O
recordings	O
of	O
the	O
same	O
piece	O
.	O
</s>
<s>
Musipedia	B-Application
is	O
included	O
in	O
some	O
library	O
catalogs	O
on	O
music-finding	O
,	O
which	O
include	O
other	O
papers	O
and	O
online	O
resources	O
.	O
</s>
<s>
Musipedia	B-Application
was	O
started	O
by	O
Rainer	O
Typke	O
in	O
1997	O
and	O
has	O
been	O
developed	O
by	O
him	O
since	O
then	O
.	O
</s>
<s>
Before	O
the	O
Wikipedia-like	O
collaboration	O
features	O
were	O
added	O
(	O
editing	O
and	O
deleting	O
existing	O
entries	O
has	O
been	O
possible	O
only	O
since	O
2004	O
)	O
,	O
he	O
called	O
the	O
music	O
search	B-Application
engine	I-Application
"	O
Melodyhound	O
"	O
.	O
</s>
<s>
Since	O
2006	O
,	O
the	O
Musipedia	B-Application
search	B-Application
engine	I-Application
can	O
also	O
be	O
used	O
for	O
searching	O
the	O
World	O
Wide	O
Web	O
for	O
MIDI	O
files	O
.	O
</s>
<s>
Musipedia	B-Application
locates	O
the	O
MIDI	O
files	O
that	O
go	O
into	O
its	O
search	O
index	O
by	O
using	O
the	O
Alexa	O
Web	B-Application
Search	I-Application
service	O
,	O
which	O
has	O
been	O
available	O
since	O
December	O
2005	O
,	O
through	O
a	O
partnership	O
with	O
Alexa	O
.	O
</s>
