<s>
LV-ROM	B-General_Concept
is	O
an	O
optical	B-Device
disc	I-Device
format	O
developed	O
by	O
Philips	O
Electronics	O
to	O
integrate	O
analog	O
video	O
and	O
computer	B-Application
software	I-Application
for	O
interactive	O
multimedia	O
.	O
</s>
<s>
The	O
LV-ROM	B-General_Concept
is	O
a	O
specialized	O
variation	O
of	O
the	O
CAV	B-Device
Laserdisc	O
.	O
</s>
<s>
LV-ROM	B-General_Concept
is	O
an	O
initialism	O
for	O
"	O
LaserVision	O
Read-Only	B-Device
Memory	I-Device
"	O
.	O
</s>
<s>
Like	O
Laserdisc	O
,	O
LV-ROM	B-General_Concept
discs	O
store	O
analog	O
audio	O
and	O
video	O
by	O
encoding	O
it	O
in	O
pulse-width	B-Algorithm
modulation	I-Algorithm
.	O
</s>
<s>
However	O
,	O
LV-ROM	B-General_Concept
also	O
stores	O
computer	B-Operating_System
files	I-Operating_System
via	O
the	O
Advanced	B-Device
Disc	I-Device
Filing	I-Device
System	I-Device
,	O
which	O
is	O
the	O
file	B-Application
system	I-Application
used	O
by	O
Acorn	O
Computers	O
.	O
</s>
<s>
An	O
LV-ROM	B-General_Concept
disc	O
can	O
store	O
up	O
to	O
324	O
megabytes	O
of	O
digital	B-General_Concept
information	I-General_Concept
,	O
or	O
up	O
to	O
54,000	O
frames	O
of	O
analog	O
video	O
(	O
36	O
minutes	O
with	O
a	O
frame	O
rate	O
of	O
25	O
fps	O
)	O
per	O
side	O
.	O
</s>
<s>
The	O
format	O
had	O
only	O
one	O
application	O
:	O
to	O
publish	O
documentary	O
video	O
,	O
children	O
's	O
writings	O
,	O
and	O
other	O
historical	O
records	O
compiled	O
from	O
1984	O
to	O
1986	O
for	O
the	B-Device
BBC	I-Device
Domesday	I-Device
Project	I-Device
.	O
</s>
<s>
The	O
Domesday	B-Device
Project	I-Device
LV-ROM	B-General_Concept
discs	O
were	O
played	O
using	O
a	O
BBC	B-Device
Master	I-Device
computer	O
connected	O
via	O
SCSI-1	O
to	O
a	O
Philips	O
AIV	O
VP415	O
Laserdisc	O
player	O
.	O
</s>
<s>
A	O
genlock	O
enabled	O
the	B-Application
software	I-Application
stored	O
on	O
the	O
LV-ROM	B-General_Concept
to	O
display	O
computer	O
graphics	O
over	O
the	O
analog	O
video	O
on	O
the	O
BBC	B-Device
Master	I-Device
's	O
computer	O
screen	O
.	O
</s>
<s>
The	O
buttons	O
and	O
menus	O
of	O
the	O
user	B-Application
interface	I-Application
were	O
accessed	O
with	O
a	O
trackball	B-Device
.	O
</s>
<s>
In	O
the	O
early	O
1990s	O
,	O
Pioneer	O
Corporation	O
deployed	O
a	O
variation	O
of	O
the	O
30-cm	O
LV-ROM	B-General_Concept
with	O
a	O
different	O
file	B-Application
system	I-Application
and	O
a	O
540	O
megabyte	O
capacity	O
.	O
</s>
<s>
This	O
disc	O
format	O
,	O
called	O
LD-ROM	O
,	O
stored	O
the	B-Application
software	I-Application
for	O
a	O
home	O
entertainment	O
system	O
that	O
Pioneer	O
introduced	O
in	O
1993	O
.	O
</s>
<s>
This	O
system	O
,	O
the	O
Pioneer	B-Device
LaserActive	I-Device
,	O
was	O
a	O
cross-platform	B-Operating_System
video	B-Device
game	I-Device
console	I-Device
,	O
Laserdisc	O
player	O
,	O
and	O
CD	B-Device
player	I-Device
.	O
</s>
<s>
LD-ROMs	O
owe	O
their	O
greater	O
capacity	O
to	O
a	O
design	O
for	O
constant	B-Device
linear	I-Device
velocity	I-Device
(	O
CLV	O
)	O
playback	O
.	O
</s>
<s>
Since	O
Pioneer	O
intended	O
LD-ROMs	O
primarily	O
for	O
computer	B-Application
software	I-Application
,	O
they	O
chose	O
CLV	O
technology	O
to	O
increase	O
the	O
file	B-Application
storage	I-Application
capacity	O
.	O
</s>
<s>
Specialized	O
LD-ROM	O
discs	O
include	O
the	O
MEGA	O
LD	O
(	O
for	O
Sega	B-Device
Mega	I-Device
CD/Sega	I-Device
CD	I-Device
software	O
)	O
,	O
the	O
LD-G	O
(	O
for	O
karaoke	O
data	O
or	O
digital	O
photo	O
albums	O
;	O
similar	O
to	O
CD+G	O
)	O
,	O
and	O
the	O
LD-ROM²	O
(	O
for	O
PC-Engine	O
CD-ROM²	O
software	O
)	O
.	O
</s>
<s>
Whereas	O
LV-ROM	B-General_Concept
is	O
an	O
abbreviation	O
of	O
"	O
LaserVision	O
Read-Only	B-Device
Memory	I-Device
"	O
,	O
LD-ROM	O
is	O
an	O
abbreviation	O
of	O
"	O
LaserDisc	O
Read-Only	B-Device
Memory	I-Device
"	O
.	O
</s>
