<s>
Indeo	B-Algorithm
Video	I-Algorithm
(	O
commonly	O
known	O
now	O
simply	O
as	O
"	O
Indeo	B-Algorithm
"	O
)	O
is	O
a	O
family	O
of	O
audio	O
and	O
video	B-Application
formats	I-Application
and	O
codecs	B-Application
first	O
released	O
in	O
1992	O
,	O
and	O
designed	O
for	O
real-time	O
video	O
playback	O
on	O
desktop	O
CPUs	O
.	O
</s>
<s>
While	O
its	O
original	O
version	O
was	O
related	O
to	O
Intel	O
's	O
DVI	B-Algorithm
video	O
stream	O
format	O
,	O
a	O
hardware-only	O
codec	O
for	O
the	O
compression	O
of	O
television-quality	O
video	O
onto	O
compact	O
discs	O
,	O
Indeo	B-Algorithm
was	O
distinguished	O
by	O
being	O
one	O
of	O
the	O
first	O
codecs	B-Application
allowing	O
full-speed	O
video	O
playback	O
without	O
using	O
hardware	O
acceleration	O
.	O
</s>
<s>
Also	O
unlike	O
Cinepak	B-Algorithm
and	O
TrueMotion	O
S	O
,	O
the	O
compression	O
used	O
the	O
same	O
Y'CbCr	O
4:2:0	O
colorspace	O
as	O
the	O
ITU	O
's	O
H.261	B-Algorithm
and	O
ISO	B-General_Concept
's	I-General_Concept
MPEG-1	B-Algorithm
.	O
</s>
<s>
Indeo	B-Algorithm
use	O
was	O
free	O
of	O
charge	O
to	O
allow	O
for	O
broadest	O
usage	O
.	O
</s>
<s>
During	O
the	O
development	O
of	O
what	O
became	O
the	O
P5	B-General_Concept
Pentium	B-Device
microprocessor	O
,	O
the	O
Intel	O
Architecture	O
Labs	O
implemented	O
one	O
of	O
the	O
first	O
,	O
and	O
at	O
the	O
time	O
highest-quality	O
,	O
software-only	O
video	B-Application
codecs	I-Application
,	O
which	O
was	O
marketed	O
as	O
"	O
Indeo	B-Algorithm
Video	I-Algorithm
"	O
.	O
</s>
<s>
It	O
has	O
been	O
developed	O
since	O
the	O
1980s	O
based	O
on	O
the	O
hardware-only	O
Digital	B-Algorithm
Video	I-Algorithm
Interactive	I-Algorithm
(	O
DVI	B-Algorithm
)	O
which	O
was	O
previously	O
developed	O
by	O
General	O
Electric	O
.	O
</s>
<s>
Indeo	B-Algorithm
was	O
first	O
released	O
in	O
1992	O
along	O
with	O
Microsoft	O
's	O
Video	B-Device
for	I-Device
Windows	I-Device
platform	O
.	O
</s>
<s>
At	O
its	O
public	O
introduction	O
,	O
it	O
was	O
the	O
only	O
video	B-Application
codec	I-Application
supported	O
in	O
both	O
the	O
Microsoft	O
(	O
Video	B-Device
for	I-Device
Windows	I-Device
)	O
and	O
Apple	O
Computer	O
's	O
QuickTime	B-Application
software	O
environments	O
,	O
as	O
well	O
as	O
by	O
IBM	O
's	O
software	O
systems	O
of	O
the	O
day	O
.	O
</s>
<s>
Though	O
Indeo	B-Algorithm
saw	O
significant	O
usage	O
in	O
the	O
mid-1990s	O
,	O
it	O
remained	O
proprietary	B-Application
.	O
</s>
<s>
Intel	O
slowed	O
development	O
and	O
stopped	O
active	O
marketing	O
,	O
and	O
it	O
was	O
quickly	O
surpassed	O
in	O
popularity	O
by	O
the	O
rise	O
of	O
MPEG	O
codecs	B-Application
and	O
others	O
,	O
as	O
processors	O
became	O
more	O
powerful	O
and	O
its	O
optimization	O
for	O
Intel	O
's	O
chips	O
less	O
important	O
.	O
</s>
<s>
Indeo	B-Algorithm
still	O
saw	O
some	O
use	O
in	O
video	O
game	O
cutscene	O
videos	B-Application
,	O
such	O
as	O
in	O
1998	O
's	O
Police	B-Application
Quest	I-Application
:	I-Application
SWAT	I-Application
2	I-Application
.	O
</s>
<s>
The	O
original	O
format	O
was	O
designed	O
for	O
real-time	O
playback	O
on	O
low-end	O
Intel	O
CPUs	O
(	O
i386	B-General_Concept
and	O
i486	B-General_Concept
)	O
,	O
optionally	O
supported	O
by	O
specialized	O
decoder	O
hardware	O
(	O
Intel	B-General_Concept
i750	I-General_Concept
)	O
.	O
</s>
<s>
Decoding	O
complexity	O
was	O
significantly	O
lower	O
than	O
with	O
contemporary	O
MPEG	O
codecs	B-Application
(	O
H.261	B-Algorithm
,	O
MPEG-1	B-Algorithm
Part	O
2	O
)	O
.	O
</s>
<s>
Indeo	B-Algorithm
2	O
,	O
previously	O
known	O
as	O
Real-Time	O
Video	O
2	O
,	O
works	O
by	O
delta	B-Algorithm
coding	I-Algorithm
pixels	O
line	O
by	O
line	O
,	O
either	O
against	O
the	O
temporally	O
or	O
spatially	O
directly	O
preceding	O
line	O
,	O
coupled	O
with	O
static	B-General_Concept
Huffman	I-General_Concept
coding	I-General_Concept
.	O
</s>
<s>
Indeo	B-Algorithm
Video	I-Algorithm
3	O
is	O
a	O
traditional	O
DCT-based	O
transform	O
coding	O
format	O
designed	O
for	O
video	O
playback	O
from	O
CD-ROM	B-Device
that	O
is	O
very	O
similar	O
to	O
the	O
competing	O
Cinepak	B-Algorithm
.	O
</s>
<s>
It	O
uses	O
chroma	O
subsampling	O
,	O
delta	B-Algorithm
encoding	I-Algorithm
,	O
vector	B-Algorithm
quantization	I-Algorithm
,	O
run-length	B-Algorithm
encoding	I-Algorithm
and	O
motion	B-Algorithm
compensation	I-Algorithm
(	O
inter-frame	B-Algorithm
coding	O
)	O
with	O
a	O
recommended	O
key-frame	O
interval	O
of	O
4	O
and	O
has	O
distinctly	O
asymmetric	O
runtime	O
characteristics	O
.	O
</s>
<s>
Indeo	B-Algorithm
Video	I-Algorithm
Interactive	O
had	O
greater	O
computational	O
complexity	O
and	O
was	O
aimed	O
at	O
video	O
game	O
developers	O
.	O
</s>
<s>
Two	O
variants	O
of	O
this	O
technology	O
were	O
produced	O
:	O
Indeo	B-Algorithm
Video	I-Algorithm
4	O
and	O
5	O
.	O
</s>
<s>
Indeo	B-Algorithm
Audio	O
Coder	O
is	O
a	O
transform	O
coding	O
format	O
based	O
on	O
the	O
modified	O
discrete	B-General_Concept
cosine	I-General_Concept
transform	I-General_Concept
(	O
MDCT	O
)	O
.	O
</s>
<s>
Proprietary	B-Application
bitstream	O
encoding	O
for	O
video	O
,	O
originally	O
developed	O
by	O
Intel	O
.	O
</s>
<s>
John	O
McGowan	O
states	O
that	O
Indeo	B-Algorithm
5	O
employs	O
a	O
wavelet	O
algorithm	O
and	O
other	O
encoding	O
features	O
;	O
its	O
predecessor	O
Indeo	B-Algorithm
4	O
employs	O
a	O
presumably	O
similar	O
"	O
hybrid	O
wavelet	O
algorithm.	O
"	O
</s>
<s>
Windows	B-Application
implementations	O
of	O
Indeo	B-Algorithm
have	O
been	O
distributed	O
by	O
Ligos	O
.	O
</s>
<s>
Apple	O
distributed	O
Mac	O
versions	O
for	O
"	O
classic	O
"	O
operating	O
systems	O
through	O
OS	O
9	O
,	O
but	O
there	O
is	O
no	O
MacOS	B-Application
support	O
for	O
Mac	B-Application
OS	I-Application
X	I-Application
.	O
</s>
<s>
Official	O
Indeo	B-Algorithm
5	O
decoders	O
exist	O
for	O
Microsoft	B-Application
Windows	I-Application
,	O
the	O
classic	B-Application
Mac	I-Application
OS	I-Application
,	O
BeOS	B-Device
R5	I-Device
and	O
the	O
XAnim	O
player	O
on	O
Unix	B-Application
.	O
</s>
<s>
Reverse	O
engineered	O
decoders	O
for	O
versions	O
2	O
,	O
3	O
,	O
4	O
and	O
5	O
were	O
introduced	O
in	O
FFmpeg	B-Library
between	O
2003	O
and	O
2011	O
.	O
</s>
<s>
Indeo	B-Algorithm
version	O
3	O
(	O
IV31	B-Algorithm
and	O
IV32	B-Algorithm
)	O
,	O
4	O
(	O
IV41	O
)	O
and	O
5	O
(	O
IV50	B-Algorithm
)	O
are	O
supported	O
by	O
MPlayer	B-Application
and	O
XAnim	O
.	O
</s>
<s>
Version	O
5.11	O
is	O
freeware	B-License
and	O
may	O
be	O
used	O
on	O
all	O
32-bit	O
versions	O
of	O
Windows	B-Application
prior	O
to	O
Vista	O
.	O
</s>
<s>
Version	O
5.2	O
has	O
been	O
created	O
for	O
XP	O
and	O
is	O
available	O
for	O
purchase	O
from	O
the	O
official	O
website	O
for	O
use	O
only	O
with	O
Windows	B-Application
95	O
,	O
98	O
,	O
ME	O
,	O
NT	O
,	O
2000	O
and	O
XP	O
.	O
</s>
<s>
This	O
includes	O
support	O
for	O
Indeo	B-Algorithm
Video	I-Algorithm
4.5	O
and	O
Indeo	B-Algorithm
Audio	O
2.5	O
codecs	B-Application
but	O
the	O
version	O
3.2	O
video	B-Application
codec	I-Application
has	O
been	O
removed	O
since	O
the	O
original	O
release	O
of	O
Indeo	B-Algorithm
XP	O
for	O
Windows	B-Application
.	O
</s>
<s>
The	O
Microsoft	B-Application
Windows	I-Application
implementation	O
of	O
the	O
Indeo	B-Algorithm
codec	O
contains	O
several	O
security	O
vulnerabilities	O
and	O
one	O
should	O
not	O
play	O
Indeo	B-Algorithm
videos	I-Algorithm
from	O
untrusted	O
sources	O
.	O
</s>
<s>
On	O
fully	O
patched	O
systems	O
and	O
all	O
Windows	B-Application
Vista	O
and	O
later	O
systems	O
,	O
the	O
Indeo	B-Algorithm
codec	O
is	O
partially	O
disabled	O
in	O
most	O
circumstances	O
.	O
</s>
