<s>
DirectMusic	B-Library
is	O
a	O
deprecated	O
component	O
of	O
the	O
Microsoft	B-Application
DirectX	I-Application
API	B-General_Concept
that	O
allows	O
music	O
and	O
sound	O
effects	O
to	O
be	O
composed	O
and	O
played	O
and	O
provides	O
flexible	O
interactive	O
control	O
over	O
the	O
way	O
they	O
are	O
played	O
.	O
</s>
<s>
Architecturally	O
,	O
DirectMusic	B-Library
is	O
a	O
high-level	O
set	O
of	O
objects	O
,	O
built	O
on	O
top	O
of	O
DirectSound	B-Device
,	O
that	O
allow	O
the	O
programmer	O
to	O
play	O
sound	O
and	O
music	O
without	O
needing	O
to	O
get	O
quite	O
as	O
low-level	O
as	O
DirectSound	B-Device
.	O
</s>
<s>
DirectSound	B-Device
allows	O
for	O
the	O
capture	O
and	O
playback	O
of	O
digital	O
sound	O
samples	O
,	O
whereas	O
DirectMusic	B-Library
works	O
with	O
message-based	O
musical	O
data	O
.	O
</s>
<s>
DirectMusic	B-Library
was	O
first	O
released	O
by	O
Microsoft	O
in	O
1996	O
as	O
an	O
ActiveX	B-Application
control	I-Application
called	O
Interactive	O
Music	O
Architecture	O
(	O
IMA	O
)	O
.	O
</s>
<s>
It	O
was	O
introduced	O
as	O
part	O
of	O
the	O
6.1	O
version	O
of	O
the	O
DirectX	B-Application
library	O
in	O
February	O
1999	O
and	O
is	O
included	O
in	O
all	O
Microsoft	B-Application
Windows	I-Application
operating	I-Application
systems	I-Application
starting	O
with	O
Windows	O
98	O
Second	O
Edition	O
.	O
</s>
<s>
DirectMusic	B-Library
has	O
since	O
been	O
deprecated	O
,	O
and	O
is	O
not	O
available	O
to	O
64-bit	O
applications	O
in	O
Windows	B-Application
Vista	I-Application
.	O
</s>
<s>
In	O
Windows	B-Device
7	I-Device
,	O
native	O
64-bit	O
support	O
is	O
available	O
for	O
the	O
core	O
DirectMusic	B-Library
API	B-General_Concept
related	O
to	O
timestamped	O
MIDI	O
but	O
not	O
for	O
the	O
performance	O
component	O
.	O
</s>
<s>
DirectMusic	B-Library
provides	O
a	O
complete	O
system	O
for	O
implementing	O
dynamic	O
soundtracks	O
that	O
take	O
advantage	O
of	O
hardware	B-General_Concept
acceleration	I-General_Concept
,	O
Downloadable	O
Sounds	O
(	O
DLS	O
)	O
,	O
DirectX	B-Application
Media	O
Objects	O
(	O
DMOs	O
)	O
,	O
advanced	O
3D	O
positioning	O
effects	O
and	O
several	O
other	O
features	O
.	O
</s>
<s>
DirectMusic	B-Library
provides	O
composition	O
and	O
playback	O
of	O
dynamic	O
musical	O
soundtracks	O
based	O
on	O
stored	O
compositional	O
material	O
.	O
</s>
<s>
Using	O
DirectMusic	B-Library
,	O
it	O
is	O
possible	O
to	O
:	O
</s>
<s>
Load	O
and	O
play	O
sounds	O
from	O
files	O
or	O
resources	O
in	O
MIDI	O
,	O
WAV	O
,	O
or	O
DirectMusic	B-Library
Producer	O
run-time	O
format	O
.	O
</s>
<s>
The	O
small	O
file	O
size	O
of	O
DirectMusic	B-Library
soundtracks	O
makes	O
it	O
very	O
well	O
suited	O
for	O
Web	O
applications	O
.	O
</s>
<s>
DirectMusic	B-Library
allows	O
timestamping	O
of	O
MIDI	O
input	O
data	O
at	O
the	O
moment	O
of	O
arrival	O
to	O
a	O
system	O
wide	O
reference	O
clock	O
.	O
</s>
<s>
Music	O
or	O
sound	O
effects	O
composed	O
for	O
DirectMusic	B-Library
can	O
be	O
very	O
flexible	O
and	O
can	O
change	O
dynamically	O
over	O
time	O
or	O
in	O
response	O
to	O
a	O
user	O
event	O
.	O
</s>
<s>
DirectMusic	B-Library
addresses	O
the	O
problems	O
of	O
Windows	O
 '	O
legacy	O
MidiOut	O
API	B-General_Concept
,	O
which	O
has	O
shaky	O
timing	O
and	O
limited	O
real-time	O
control	O
.	O
</s>
<s>
Send	O
tempo	B-Application
changes	O
,	O
patch	O
changes	O
,	O
and	O
other	O
MIDI	O
events	O
programmatically	O
.	O
</s>
<s>
On	O
computers	O
with	O
sound	O
card	O
which	O
lack	O
'	O
wavetable	O
 '	O
sample-based	O
synthesis	O
,	O
DirectSound	B-Device
's	O
Software	B-Application
Synthesizer	I-Application
ensures	O
that	O
message-based	O
music	O
such	O
as	O
MIDI	O
files	O
and	O
DirectMusic	B-Library
segments	O
sound	O
identical	O
on	O
all	O
hardware	O
configurations	O
rather	O
than	O
playing	O
differently	O
on	O
different	O
computers	O
with	O
different	O
sound	O
cards	O
.	O
</s>
<s>
DirectMusic	B-Library
makes	O
it	O
possible	O
for	O
any	O
number	O
of	O
voices	O
to	O
be	O
played	O
simultaneously	O
,	O
up	O
to	O
the	O
limits	O
of	O
the	O
synthesizer	O
.	O
</s>
<s>
DirectMusic	B-Library
Producer	O
can	O
be	O
used	O
to	O
create	O
sound	O
files	O
that	O
take	O
full	O
advantage	O
of	O
DirectMusic	B-Library
's	O
interactive	O
features	O
.	O
</s>
<s>
On	O
Microsoft	B-Application
Windows	I-Application
Vista	I-Application
,	O
DirectMusic	B-Library
uses	O
only	O
software	B-Application
synthesis	I-Application
.	O
</s>
<s>
Also	O
,	O
the	O
DirectMusic	B-Library
kernel	O
mode	O
synthesizer	O
that	O
supplies	O
the	O
DirectMusic	B-Library
components	O
with	O
a	O
high-resolution	O
timer	O
has	O
been	O
removed	O
.	O
</s>
