<s>
Α	O
video	B-Application
codec	I-Application
is	O
software	O
or	O
a	O
device	O
that	O
provides	O
encoding	B-Algorithm
and	O
decoding	O
for	O
digital	O
video	O
,	O
and	O
which	O
may	O
or	O
may	O
not	O
include	O
the	O
use	O
of	O
video	O
compression	O
and/or	O
decompression	O
.	O
</s>
<s>
Most	O
codecs	O
are	O
typically	O
implementations	O
of	O
video	B-Algorithm
coding	I-Algorithm
formats	I-Algorithm
.	O
</s>
<s>
The	O
compression	O
may	O
employ	O
lossy	B-Algorithm
data	I-Algorithm
compression	I-Algorithm
,	O
so	O
that	O
quality-measurement	O
issues	O
become	O
important	O
.	O
</s>
<s>
The	O
following	O
characteristics	O
are	O
compared	O
in	O
video	B-Application
codecs	I-Application
comparisons	O
:	O
</s>
<s>
Video	B-Device
quality	I-Device
per	O
bitrate	O
(	O
or	O
range	O
of	O
bitrates	O
)	O
.	O
</s>
<s>
Commonly	O
video	B-Device
quality	I-Device
is	O
considered	O
the	O
main	O
characteristic	O
of	O
codec	B-Application
comparisons	O
.	O
</s>
<s>
Video	B-Device
quality	I-Device
comparisons	O
can	O
be	O
subjective	B-Device
or	O
objective	O
.	O
</s>
<s>
Supported	O
interfaces	O
(	O
VfW	O
,	O
DirectShow	B-Library
,	O
etc	O
.	O
)	O
</s>
<s>
The	O
quality	B-Device
the	O
codec	B-Application
can	O
achieve	O
is	O
heavily	O
based	O
on	O
the	O
compression	O
format	O
the	O
codec	B-Application
uses	O
.	O
</s>
<s>
A	O
codec	B-Application
is	O
not	O
a	O
format	O
,	O
and	O
there	O
may	O
be	O
multiple	O
codecs	O
that	O
implement	O
the	O
same	O
compression	O
specification	O
for	O
example	O
,	O
MPEG-1	B-Algorithm
codecs	O
typically	O
do	O
not	O
achieve	O
quality/size	O
ratio	O
comparable	O
to	O
codecs	O
that	O
implement	O
the	O
more	O
modern	O
H.264	B-Application
specification	O
.	O
</s>
<s>
But	O
quality/size	O
ratio	O
of	O
output	O
produced	O
by	O
different	O
implementations	O
of	O
the	O
same	O
specification	O
can	O
also	O
vary	O
.	O
</s>
<s>
Each	O
compression	O
specification	O
defines	O
various	O
mechanisms	O
by	O
which	O
raw	O
video	O
(	O
in	O
essence	O
,	O
a	O
sequence	O
of	O
full-resolution	O
uncompressed	O
digital	O
images	O
)	O
can	O
be	O
reduced	O
in	O
size	O
,	O
from	O
simple	O
bit	O
compression	O
(	O
like	O
Lempel-Ziv-Welch	B-Algorithm
)	O
to	O
psycho-visual	O
and	O
motion	O
summarization	O
,	O
and	O
how	O
the	O
output	O
is	O
stored	O
as	O
a	O
bit	O
stream	O
.	O
</s>
<s>
So	O
long	O
as	O
the	O
encoder	O
component	O
of	O
the	O
codec	B-Application
adheres	O
to	O
the	O
specification	O
it	O
can	O
choose	O
any	O
combination	O
of	O
these	O
methods	O
to	O
apply	O
different	O
parts	O
of	O
the	O
content	O
.	O
</s>
<s>
The	O
decoder	O
component	O
of	O
a	O
codec	B-Application
that	O
also	O
conforms	O
to	O
the	O
specification	O
recognises	O
each	O
of	O
the	O
mechanisms	O
used	O
,	O
and	O
thus	O
interprets	O
the	O
compressed	O
stream	O
to	O
render	O
it	O
back	O
into	O
raw	O
video	O
for	O
display	O
(	O
although	O
this	O
will	O
not	O
be	O
identical	O
to	O
the	O
raw	O
video	O
input	O
unless	O
the	O
compression	O
was	O
lossless	B-Algorithm
)	O
.	O
</s>
<s>
Each	O
encoder	O
implements	O
the	O
specification	O
according	O
to	O
its	O
own	O
algorithms	O
and	O
parameters	O
,	O
which	O
means	O
that	O
the	O
compressed	O
output	O
of	O
different	O
codecs	O
will	O
vary	O
,	O
resulting	O
in	O
variations	O
in	O
quality	B-Device
and	O
efficiency	O
between	O
them	O
.	O
</s>
<s>
Prior	O
to	O
comparing	O
codec	B-Application
video-quality	O
,	O
it	O
is	O
important	O
to	O
understand	O
that	O
every	O
codec	B-Application
can	O
give	O
a	O
varying	O
degree	O
of	O
quality	B-Device
for	O
a	O
given	O
set	O
of	O
frames	O
within	O
a	O
video	O
sequence	O
.	O
</s>
<s>
First	O
,	O
all	O
codecs	O
have	O
a	O
bitrate	O
control	O
mechanism	O
that	O
is	O
responsible	O
for	O
determining	O
the	O
bitrate	O
and	O
quality	B-Device
on	O
a	O
per-frame	O
basis	O
.	O
</s>
<s>
A	O
difference	O
between	O
variable	B-General_Concept
bitrate	I-General_Concept
(	O
VBR	O
)	O
and	O
constant	B-General_Concept
bitrate	I-General_Concept
(	O
CBR	B-General_Concept
)	O
creates	O
a	O
trade-off	O
between	O
a	O
consistent	O
quality	B-Device
over	O
all	O
frames	O
,	O
on	O
the	O
one	O
hand	O
,	O
and	O
a	O
more	O
constant	B-General_Concept
bitrate	I-General_Concept
,	O
which	O
is	O
required	O
for	O
some	O
applications	O
,	O
on	O
the	O
other	O
.	O
</s>
<s>
Second	O
,	O
some	O
codecs	O
differentiate	O
between	O
different	O
types	O
of	O
frames	O
,	O
such	O
as	O
key	O
frames	O
and	O
non-key	O
frames	O
,	O
differing	O
in	O
their	O
importance	O
to	O
overall	O
visual	O
quality	B-Device
and	O
the	O
extent	O
to	O
which	O
they	O
can	O
be	O
compressed	O
.	O
</s>
<s>
Third	O
,	O
quality	B-Device
depends	O
on	O
prefiltrations	O
,	O
which	O
are	O
included	O
on	O
all	O
present-day	O
codecs	O
.	O
</s>
<s>
For	O
a	O
sufficiently	O
long	O
clip	O
,	O
it	O
is	O
possible	O
to	O
select	O
sequences	O
that	O
have	O
suffered	O
little	O
from	O
the	O
compression	O
,	O
and	O
sequences	O
that	O
have	O
suffered	O
heavily	O
,	O
especially	O
if	O
CBR	B-General_Concept
has	O
been	O
used	O
,	O
whereby	O
the	O
quality	B-Device
between	O
frames	O
can	O
vary	O
highly	O
due	O
to	O
different	O
amounts	O
of	O
compression	O
needed	O
to	O
achieve	O
a	O
constant	B-General_Concept
bitrate	I-General_Concept
.	O
</s>
<s>
So	O
,	O
in	O
a	O
given	O
long	O
clip	O
,	O
such	O
as	O
a	O
full-length	O
movie	O
,	O
any	O
two	O
codecs	O
may	O
perform	O
quite	O
differently	O
on	O
a	O
particular	O
sequence	O
from	O
the	O
clip	O
,	O
while	O
the	O
codecs	O
may	O
be	O
approximately	O
equal	O
(	O
or	O
the	O
situation	O
reversed	O
)	O
in	O
quality	B-Device
over	O
a	O
wider	O
sequence	O
of	O
frames	O
.	O
</s>
<s>
Press-releases	O
and	O
amateur	O
forums	O
may	O
sometimes	O
select	O
sequences	O
known	O
to	O
favor	O
a	O
particular	O
codec	B-Application
or	O
style	O
of	O
rate-control	O
in	O
reviews	O
.	O
</s>
<s>
Objective	O
video	O
evaluation	O
techniques	O
are	O
mathematical	O
models	O
that	O
seek	O
to	O
predict	O
human	O
judgments	O
of	O
picture	O
quality	B-Device
,	O
as	O
often	O
exemplified	O
by	O
the	O
results	O
of	O
subjective	B-Device
quality	B-Device
assessment	O
experiments	O
.	O
</s>
<s>
Objective	O
methods	O
are	O
classified	O
based	O
on	O
the	O
availability	O
of	O
an	O
original	O
pristine	O
video	O
signal	O
,	O
which	O
is	O
considered	O
to	O
be	O
of	O
high	O
quality	B-Device
(	O
generally	O
not	O
compressed	O
)	O
.	O
</s>
<s>
Subjective	B-Device
video	I-Device
quality	I-Device
tests	O
are	O
quite	O
expensive	O
with	O
regard	O
to	O
time	O
(	O
preparation	O
and	O
running	O
)	O
and	O
human	O
resources	O
.	O
</s>
<s>
The	O
reason	O
for	O
measuring	O
subjective	B-Device
video	I-Device
quality	I-Device
is	O
the	O
same	O
as	O
for	O
measuring	O
the	O
mean	O
opinion	O
score	O
for	O
audio	O
.	O
</s>
<s>
In	O
the	O
case	O
of	O
video	B-Application
codecs	I-Application
,	O
this	O
is	O
a	O
very	O
common	O
situation	O
.	O
</s>
<s>
When	O
codecs	O
with	O
similar	O
objective	O
results	O
show	O
results	O
with	O
different	O
subjective	B-Device
results	O
,	O
the	O
main	O
reasons	O
can	O
be	O
:	O
</s>
<s>
Denoising	O
and	O
deflicking	O
normally	O
maintain	O
PSNR	O
value	O
while	O
increasing	O
visual	O
quality	B-Device
(	O
the	O
best	O
slow	O
denoising	O
filters	O
also	O
increase	O
PSNR	O
on	O
medium	O
and	O
high	O
bitrates	O
)	O
.	O
</s>
<s>
Deshaking	O
greatly	O
decreases	O
PSNR	O
,	O
but	O
increases	O
visual	O
quality	B-Device
.	O
</s>
<s>
Postfilters	O
show	O
similar	O
characteristics	O
deblocking	O
and	O
deringing	O
maintain	O
PSNR	O
,	O
but	O
increase	O
quality	B-Device
;	O
graining	O
(	O
suggested	O
in	O
H.264	B-Application
)	O
essentially	O
increases	O
video	B-Device
quality	I-Device
,	O
especially	O
on	O
big	O
plasma	O
screens	O
,	O
but	O
decreases	O
PSNR	O
.	O
</s>
<s>
All	O
filters	O
increase	O
compression/decompression	O
time	O
,	O
so	O
they	O
enhance	O
visual	O
quality	B-Device
but	O
decrease	O
the	O
speed	O
of	O
coding	B-Algorithm
and	I-Algorithm
decoding	I-Algorithm
.	O
</s>
<s>
Motion	O
estimation	O
(	O
ME	O
)	O
search	O
strategy	O
can	O
also	O
cause	O
different	O
visual	O
quality	B-Device
for	O
the	O
same	O
PSNR	O
.	O
</s>
<s>
So-called	O
true	O
motion	O
search	O
commonly	O
will	O
not	O
reach	O
minimum	O
sum	B-Algorithm
of	I-Algorithm
absolute	I-Algorithm
differences	I-Algorithm
(	O
SAD	O
)	O
values	O
in	O
codec	B-Application
ME	O
,	O
but	O
may	O
result	O
in	O
better	O
visual	O
quality	B-Device
.	O
</s>
<s>
VBR	O
commonly	O
cause	O
better	O
visual	O
quality	B-Device
marks	O
than	O
CBR	B-General_Concept
for	O
the	O
same	O
average	O
PSNR	O
values	O
for	O
sequences	O
.	O
</s>
<s>
It	O
is	O
difficult	O
to	O
use	O
long	O
sequences	O
for	O
subjective	B-Device
testing	O
.	O
</s>
<s>
The	O
following	O
issues	O
should	O
be	O
considered	O
when	O
estimating	O
probable	O
codec	B-Application
performance	O
differences	O
:	O
</s>
<s>
SIMD	B-Device
support	O
by	O
processor	O
and	O
codec	B-Application
E.g.	O
,	O
MMX	B-Architecture
,	O
SSE	B-General_Concept
,	O
SSE2	B-General_Concept
,	O
each	O
of	O
which	O
change	O
CPU	O
performance	O
on	O
some	O
kinds	O
of	O
tasks	O
(	O
often	O
including	O
those	O
with	O
which	O
codecs	O
are	O
concerned	O
)	O
.	O
</s>
<s>
Multi-threading	O
support	O
by	O
processor	O
and	O
codec	B-Application
Sometimes	O
turning	O
on	O
Hyper-threading	B-Operating_System
support	O
(	O
if	O
available	O
on	O
a	O
particular	O
CPU	O
)	O
causes	O
codec	B-Application
speed	O
to	O
decrease	O
.	O
</s>
<s>
for	O
CPUs	O
with	O
low	O
cache	O
such	O
as	O
several	O
of	O
the	O
Intel	B-Device
Celeron	I-Device
series	O
.	O
</s>
<s>
GPU	B-Architecture
usage	O
by	O
codec	B-Application
some	O
codecs	O
can	O
drastically	O
increase	O
their	O
performance	O
by	O
taking	O
advantage	O
of	O
GPU	B-Architecture
resources	O
.	O
</s>
<s>
So	O
,	O
for	O
example	O
,	O
codec	B-Application
A	O
(	O
being	O
optimized	O
for	O
memory	O
usage	O
i.e.	O
,	O
uses	O
less	O
memory	O
)	O
may	O
,	O
on	O
modern	O
computers	O
(	O
which	O
are	O
typically	O
not	O
memory-limited	O
)	O
,	O
give	O
slower	O
performance	O
than	O
codec	B-Application
B	O
.	O
</s>
<s>
(	O
This	O
is	O
very	O
common	O
for	O
H.264	B-Application
implementations	O
for	O
example	O
.	O
)	O
</s>
<s>
The	O
H.264	B-Application
standard	O
includes	O
the	O
following	O
seven	O
sets	O
of	O
capabilities	O
,	O
which	O
are	O
referred	O
to	O
as	O
profiles	O
,	O
targeting	O
specific	O
classes	O
of	O
applications	O
:	O
</s>
<s>
(	O
This	O
is	O
the	O
profile	O
adopted	O
into	O
HD	B-Operating_System
DVD	I-Operating_System
and	O
Blu-ray	O
Disc	O
,	O
for	O
example	O
.	O
)	O
</s>
<s>
High	O
4:4:4	O
Predictive	O
Profile	O
(	O
Hi444PP	O
)	O
:	O
This	O
profile	O
builds	O
on	O
top	O
of	O
the	O
High	O
4:2:2	O
Profile	O
,	O
supporting	O
up	O
to	O
4:4:4	O
chroma	O
sampling	O
,	O
up	O
to	O
14	O
bits	O
per	O
sample	O
,	O
and	O
additionally	O
supporting	O
efficient	O
lossless	B-Algorithm
region	O
coding	O
and	O
the	O
coding	O
of	O
each	O
picture	O
as	O
three	O
separate	O
color	O
planes	O
.	O
</s>
<s>
CAVLC	B-Algorithm
4:4:4	O
Intra	O
Profile	O
:	O
The	O
High	O
4:4:4	O
Profile	O
constrained	O
to	O
all-Intra	O
use	O
and	O
to	O
CAVLC	B-Algorithm
entropy	O
coding	O
(	O
i.e.	O
,	O
not	O
supporting	O
CABAC	B-Algorithm
)	O
.	O
</s>
<s>
Moreover	O
,	O
the	O
standard	O
now	O
also	O
contains	O
three	O
Scalable	B-Application
Video	I-Application
Coding	I-Application
profiles	O
.	O
</s>
<s>
An	O
accurate	O
comparison	O
of	O
codecs	O
must	O
take	O
the	O
profile	O
variations	O
within	O
each	O
codec	B-Application
into	O
account	O
.	O
</s>
<s>
See	O
also	O
MPEG-2	B-Algorithm
Profiles	O
and	O
Levels	O
.	O
</s>
<s>
Constant	B-General_Concept
bitrate	I-General_Concept
(	O
CBR	B-General_Concept
)	O
.	O
</s>
<s>
Variable	B-General_Concept
bitrate	I-General_Concept
(	O
VBR	O
)	O
is	O
a	O
strategy	O
to	O
maximize	O
the	O
visual	O
video	B-Device
quality	I-Device
and	O
minimize	O
the	O
bitrate	O
.	O
</s>
<s>
On	O
fast-motion	O
scenes	O
,	O
a	O
variable	B-General_Concept
bitrate	I-General_Concept
uses	O
more	O
bits	O
than	O
it	O
does	O
on	O
slow-motion	O
scenes	O
of	O
similar	O
duration	O
,	O
yet	O
achieves	O
a	O
consistent	O
visual	O
quality	B-Device
.	O
</s>
<s>
in	O
videoconferencing	O
delivered	O
on	O
channels	O
of	O
fixed	O
bandwidth	O
a	O
constant	B-General_Concept
bitrate	I-General_Concept
(	O
CBR	B-General_Concept
)	O
must	O
be	O
used	O
.	O
</s>
<s>
CBR	B-General_Concept
is	O
commonly	O
used	O
for	O
videoconferences	O
,	O
satellite	O
and	O
cable	O
broadcasting	O
.	O
</s>
<s>
For	O
offline	O
storage	O
and	O
viewing	O
,	O
it	O
is	O
typically	O
preferable	O
to	O
encode	O
at	O
constant	O
quality	B-Device
(	O
usually	O
defined	O
by	O
quantization	B-Algorithm
)	O
rather	O
than	O
using	O
bit	O
rate	O
control	O
.	O
</s>
<s>
+General	O
video	B-Application
codec	I-Application
information	O
creator/company	O
,	O
license/price	O
,	O
etc	O
.	O
</s>
<s>
Codec	B-Application
Creator/Maintainer	O
First	O
public	O
release	O
date	O
Latest	O
stable	O
version	O
License	B-License
Patented	O
compression	B-Algorithm
formats	I-Algorithm
Compression	O
method	O
Basic	O
algorithm	O
OpenCL	B-Application
support	O
nVidia	B-Architecture
CUDA	I-Architecture
support	O
Intel	O
SSE	B-General_Concept
Support	O
Intel	O
AVX	B-General_Concept
support	O
Intel	B-Algorithm
Quick	I-Algorithm
Sync	I-Algorithm
Video	I-Algorithm
support	O
AOM	O
Video	O
1	O
(	O
AV1	B-Application
)	O
Alliance	O
for	O
Open	O
Media	O
2018-06-25	O
1.0.0	O
Errata	O
1	O
(	O
2019	O
)	O
Lossy	B-Algorithm
/	O
Lossless	B-Algorithm
DCT	B-General_Concept
libtheora	B-Algorithm
(	O
Theora	B-Algorithm
)	O
Xiph.org	B-Application
2002-09-25	O
1.1.1	O
(	O
2009	O
)	O
Xiph.Org	B-Application
Foundation	I-Application
(	O
2009	O
)	O
Theora	B-Algorithm
development	O
website	O
-	O
news	O
,	O
Retrieved	O
2009-10-06	O
Lossy	B-Algorithm
DCT	B-General_Concept
dirac-research	O
(	O
Dirac	B-Application
)	O
BBC	B-Application
Research	I-Application
Department	I-Application
2008-09-17	O
1.0.2	O
(	O
2009	O
)	O
Dirac	B-Application
Video	O
Compression	O
Lossy	B-Algorithm
/	O
Lossless	B-Algorithm
DWT	O
CineForm	B-Algorithm
GoPro	B-Device
2001	O
10.0.2	O
(	O
2019	O
)	O
Releases	O
·	O
gopro/cineform	O
-sdk	O
Lossy	B-Algorithm
DWT	O
Schrödinger	O
(	O
Dirac	B-Application
)	O
David	O
Schleef	O
2008-02-22	O
1.0.11	O
(	O
2012	O
)	O
Lossy	B-Algorithm
/	O
Lossless	B-Algorithm
DWT	O
x264	B-Language
x264	B-Language
team	O
2003	O
r3079	O
(	O
2021	O
)	O
x264	B-Language
Encoder	O
164	O
r3079	O
Free	O
Download	O
-	O
VideoHelp	O
,	O
Retrieved	O
on	O
2021-12-14	O
Lossy	B-Algorithm
/	O
Lossless	B-Algorithm
DCT	B-General_Concept
x265	B-Language
x265	B-Language
team	O
2013	O
3.5	O
(	O
2021	O
)	O
Lossy	B-Algorithm
/	O
Lossless	B-Algorithm
DCT	B-General_Concept
Xvid	B-Algorithm
Xvid	B-Algorithm
team	O
2001	O
1.3.7	O
(	O
2019	O
)	O
Lossy	B-Algorithm
DCT	B-General_Concept
FFmpeg	B-Library
(	O
libavcodec	B-Language
)	O
FFmpeg	B-Library
team	O
2000	O
4.4.1	O
(	O
2021	O
)	O
FFmpeg.org,	O
Retrieved	O
on	O
2021-12-14	O
Lossy	B-Algorithm
/	O
Lossless	B-Algorithm
DCT	B-General_Concept
FFavs	O
(	O
libavcodec	B-Language
)	O
FFavs	O
team	O
2009	O
0.0.3	O
(	O
2009	O
)	O
FFavs	O
Lossy	B-Algorithm
/	O
Lossless	B-Algorithm
DCT	B-General_Concept
OpenH264	B-Language
Cisco	O
Systems	O
2014-05	O
2.1.1	O
(	O
2020	O
)	O
OpenH264	B-Language
Releases	O
Lossy	B-Algorithm
DCT	B-General_Concept
Blackbird	O
Forbidden	O
Technologies	O
plc	O
2006-01	O
9	O
(	O
2017	O
)	O
Lossy	B-Algorithm
Adaptive	B-Algorithm
coding	I-Algorithm
DivX	B-Application
DivX	B-Application
,	O
Inc	O
.	O
2001	O
DivX	B-Application
Software	O
10.9.1	O
(	O
2023	O
)	O
Lossy	B-Algorithm
DCT	B-General_Concept
a	O
hack	O
of	O
Microsoft	O
's	O
MPEG-4v3	O
codecVirtualDub	O
VirtualDub	O
documentation	O
:	O
codecs	O
,	O
Retrieved	O
on	O
2009-08-08FOURCC.org	O
Video	B-Application
Codecs	I-Application
-	O
Compressed	O
Formats	O
,	O
Retrieved	O
on	O
2009-08-08	O
1998	O
3.20	O
alphaTom	O
's	O
Hardware	O
(	O
2001-10-22	O
)	O
A	O
Tough	O
Choice	O
:	O
DivX	B-Application
3.20a	O
Codec	B-Application
Still	O
Better	O
Than	O
DivX	B-Application
4.01	O
Codec	B-Application
,	O
Retrieved	O
on	O
2009-08-08	O
(	O
2000	O
)	O
Lossy	B-Algorithm
DCT	B-General_Concept
3ivx	B-Algorithm
3ivx	B-Algorithm
Technologies	O
Pty	O
.	O
</s>
<s>
Ltd	O
.	O
2001	O
5.0.5	O
(	O
2012	O
)	O
3ivx	B-Algorithm
,	O
Retrieved	O
on	O
2014-12-27	O
Lossy	B-Algorithm
DCT	B-General_Concept
Nero	B-Algorithm
Digital	I-Algorithm
Nero	O
AG	O
2003	O
1.5.4.0	O
(	O
2010	O
)	O
Lossy	B-Algorithm
DCT	B-General_Concept
ProRes	O
422	O
/	O
ProRes	O
4444	O
Apple	O
Inc	O
.	O
2007	O
Lossy	B-Algorithm
DCT	B-General_Concept
Sorenson	O
Video	O
Sorenson	O
Media	O
1998	O
Lossy	B-Algorithm
DCT	B-General_Concept
Sorenson	O
Spark	O
Sorenson	O
Media	O
2002	O
Lossy	B-Algorithm
DCT	B-General_Concept
VP3	B-Algorithm
On2	B-Application
Technologies	I-Application
2000	O
Lossy	B-Algorithm
DCT	B-General_Concept
VP4	O
On2	B-Application
Technologies	I-Application
2001	O
Lossy	B-Algorithm
DCT	B-General_Concept
VP5	O
On2	B-Application
Technologies	I-Application
2002	O
Lossy	B-Algorithm
DCT	B-General_Concept
VP6	B-Algorithm
On2	B-Application
Technologies	I-Application
2003	O
Lossy	B-Algorithm
DCT	B-General_Concept
VP7	O
On2	B-Application
Technologies	I-Application
2005	O
Lossy	B-Algorithm
DCT	B-General_Concept
libvpx	B-Language
(	O
VP8	B-Algorithm
)	O
On2	B-Application
Technologies	I-Application
(	O
now	O
owned	O
by	O
Google	B-Application
)	O
2008	O
1.11.0	O
(	O
2021	O
)	O
refs/tags/v1.11.0	O
-	O
webm/libvpx	O
-	O
Git	O
at	O
Google	B-Application
,	O
Retrieved	O
on	O
14	O
December	O
2021	O
Lossy	B-Algorithm
DCT	B-General_Concept
libvpx	B-Language
(	O
VP9	B-Algorithm
)	O
Google	B-Application
2013	O
1.11.0	O
(	O
2021	O
)	O
Lossy	B-Algorithm
/	O
Lossless	B-Algorithm
DCT	B-General_Concept
DNxHD	O
Avid	O
Technology	O
2004	O
Lossy	B-Algorithm
DCT	B-General_Concept
Cinema	O
Craft	O
Encoder	O
SP2	O
Custom	O
Technology	O
Corporation	O
2000	O
1.00.01.09	O
(	O
2009	O
)	O
Custom	O
Technology	O
Corporation	O
CINEMA	O
CRAFT	O
-	O
Download	O
,	O
Retrieved	O
on	O
2009-08-11	O
Lossy	B-Algorithm
DCT	B-General_Concept
TMPGEnc	B-Application
Free	O
Version	O
Pegasys	O
Inc	O
.	O
2001	O
2.525.64.184	O
(	O
2008	O
)	O
Pegasys	O
Inc	O
.	O
What	O
Is	O
New	O
,	O
Retrieved	O
on	O
2009-08-11	O
Lossy	B-Algorithm
DCT	B-General_Concept
Windows	B-Protocol
Media	I-Protocol
Encoder	I-Protocol
Microsoft	O
1999	O
9	O
(	O
2003	O
)	O
(	O
WMV3	B-Device
in	O
FourCC	B-Application
)	O
Lossy	B-Algorithm
DCT	B-General_Concept
Cinepak	B-Algorithm
Created	O
by	O
SuperMac	O
,	O
Inc.	O
,	O
acquired	O
and	O
patented	O
by	O
Radius	O
,	O
Inc	O
.	O
</s>
<s>
The	O
Xiph.Org	B-Application
Foundation	I-Application
has	O
negotiated	O
an	O
irrevocable	O
free	O
license	B-License
to	O
Theora	B-Algorithm
and	O
other	O
VP3-derived	O
codecs	O
for	O
everyone	O
,	O
for	O
any	O
purpose	O
.	O
</s>
<s>
DivX	B-Application
Plus	O
is	O
also	O
known	O
as	O
DivX	B-Application
8	O
.	O
</s>
<s>
The	O
latest	O
stable	O
version	O
for	O
Mac	O
is	O
DivX	B-Application
7	O
for	O
Mac	O
.	O
</s>
<s>
Note	O
that	O
operating	O
system	O
support	O
does	O
not	O
mean	O
whether	O
video	O
encoded	B-Algorithm
with	O
the	O
codec	B-Application
can	O
be	O
played	O
back	O
on	O
the	O
particular	O
operating	O
system	O
for	O
example	O
,	O
video	O
encoded	B-Algorithm
with	O
the	O
DivX	B-Application
codec	I-Application
is	O
playable	O
on	O
Unix-like	B-Operating_System
systems	I-Operating_System
using	O
free	O
MPEG-4	B-Application
ASP	I-Application
decoders	O
(	O
FFmpeg	B-Library
MPEG-4	O
or	O
Xvid	B-Algorithm
)	O
,	O
but	O
the	O
DivX	B-Application
codec	I-Application
(	O
which	O
is	O
a	O
software	O
product	O
)	O
is	O
only	O
available	O
for	O
Windows	B-Application
and	O
macOS	B-Application
.	O
</s>
<s>
Codec	B-Application
Compression	O
type	O
Basic	O
algorithm	O
Highest	O
supported	O
bitrate	O
Highest	O
supported	O
resolution	B-Algorithm
Variable	B-General_Concept
frame	I-General_Concept
rate	I-General_Concept
Blackbird	O
Lossy	B-Algorithm
compression	I-Algorithm
384×288	O
(	O
PAL	O
)	O
,	O
320×240	O
(	O
NTSC	O
)	O
Cinepak	B-Algorithm
Lossy	B-Algorithm
compression	I-Algorithm
Vector	O
quantizationTechnical	O
description	O
of	O
the	O
Cinepak	B-Algorithm
codec	I-Algorithm
Dirac	B-Application
Lossy	B-Algorithm
/	O
Lossless	B-Algorithm
compression	I-Algorithm
Wavelet	O
compression	O
UnlimitedFrame	O
rate	O
,	O
resolution	B-Algorithm
,	O
etc	O
.	O
</s>
<s>
Unlimited	O
Sorenson	O
3	O
Lossy	B-Algorithm
compression	I-Algorithm
Discrete	B-General_Concept
cosine	I-General_Concept
transform	I-General_Concept
Theora	B-Algorithm
Lossy	B-Algorithm
compression	I-Algorithm
Discrete	B-General_Concept
cosine	I-General_Concept
transform	I-General_Concept
2	O
Gibit/s	O
1,048,560	O
×	O
1,048,560	O
Requires	O
about	O
3	O
terabytes	O
per	O
uncompressed	O
frame	O
at	O
maximum	O
resolution	B-Algorithm
(	O
pg	O
37	O
,	O
Theora	B-Algorithm
I	O
Specification	O
.	O
</s>
<s>
Theora	B-Algorithm
streams	O
with	O
different	O
frame	O
rates	O
can	O
be	O
chained	O
in	O
the	O
same	O
file	O
,	O
but	O
each	O
stream	O
has	O
a	O
fixed	O
frame	O
rate	O
.	O
</s>
<s>
Dirac	B-Application
,	O
Elecard	O
AVC	O
HP	O
,	O
libavcodec	B-Language
MPEG-4	O
,	O
NeroDigital	B-Algorithm
ASP	O
,	O
QuickTime	O
7	O
,	O
Snow	O
,	O
Theora	B-Algorithm
,	O
VideoSoft	O
H.264	B-Application
HP	O
,	O
XviD	B-Algorithm
1.1	O
beta	O
2	O
in	O
last	O
one	O
Subjective	B-Device
comparison	O
with	O
convenient	O
visualization	O
Series	O
of	O
MSU	O
annual	O
video	B-Application
codecs	I-Application
comparisons	O
Series	O
of	O
objective	O
HEVC/AV1	O
codecs	O
comparisons	O
2015	O
Oct	O
.	O
</s>
<s>
2013	O
Dec	O
.	O
2005	O
(	O
Jan	O
.	O
)	O
:	O
Mpegable	O
AVC	O
,	O
Moonlight	O
H.264	B-Application
,	O
MainConcept	B-Algorithm
H.264	B-Application
,	O
Fraunhofer	O
IIS	O
,	O
Ateme	O
MPEG-4	B-Application
AVC/H.264	I-Application
,	O
Videosoft	O
H.264	B-Application
,	O
DivX	B-Application
Pro	I-Application
5.1.1	O
(	O
Not	O
264	O
!	O
</s>
<s>
2012	O
:	O
DivX	B-Application
H.264	I-Application
,	O
Elecard	O
H.264	B-Application
,	O
Intel	O
Ivy	O
Bridge	O
QuickSync	B-Algorithm
(	O
GPU	B-Architecture
encoder	O
)	O
,	O
MainConcept	B-Algorithm
H.264	B-Application
(	O
software	O
)	O
,	O
MainConcept	B-Algorithm
H.264	B-Application
(	O
CUDA	B-Architecture
based	O
encoder	O
)	O
,	O
MainConcept	B-Algorithm
H.264	B-Application
(	O
OpenCL	B-Application
based	O
encoder	O
)	O
,	O
DiscretePhoton	O
,	O
x264	B-Language
,	O
XviD	B-Algorithm
(	O
MPEG-4	B-Application
ASP	I-Application
codec	B-Application
)	O
Detailed	O
objective	O
comparisons	O
Series	O
of	O
Lossless	B-Application
Video	I-Application
Codecs	I-Application
Comparison	O
Two	O
size	O
and	O
time	O
comparisons	O
of	O
lossless	B-Algorithm
codecs	I-Algorithm
(	O
with	O
lossless	B-Algorithm
checking	O
)	O
2004	O
Oct	O
.	O
</s>
<s>
2007	O
(	O
16	O
codecs	O
)	O
:	O
Alpary	O
,	O
ArithYuv	O
,	O
AVIzlib	O
,	O
CamStudio	O
GZIP	O
,	O
CorePNG	O
,	O
FastCodec	O
,	O
FFV1	O
,	O
Huffyuv	B-Algorithm
,	O
Lagarith	B-Algorithm
,	O
LOCO	O
,	O
LZO	O
,	O
MSU	O
Lab	O
,	O
PICVideo	O
,	O
Snow	O
,	O
x264	B-Language
,	O
YULS	O
in	O
2007	O
more	O
detailed	O
report	O
with	O
new	O
codecs	O
including	O
first	O
standard	O
H.264	B-Application
(	O
x264	B-Language
)	O
MSU	O
MPEG-4	O
codecs	O
comparison	O
Objective	O
comparison	O
of	O
MPEG-4	O
codecs	O
2005	O
Mar	O
.	O
</s>
<s>
DivX	B-Application
5.2.1	O
,	O
DivX	B-Application
4.12	O
,	O
DivX	B-Application
3.22	O
,	O
MS	O
MPEG-4	O
3688	O
v3	O
,	O
XviD	B-Algorithm
1.0.3	O
,	O
3ivx	B-Algorithm
D4	O
4.5.1	O
,	O
OpenDivX	B-Algorithm
0.3	O
Different	O
versions	O
of	O
DivX	B-Application
were	O
also	O
compared	O
.	O
</s>
<s>
The	O
Xvid	B-Algorithm
results	O
may	O
be	O
erroneous	O
,	O
as	O
deblocking	O
was	O
disabled	O
for	O
it	O
while	O
used	O
for	O
DivX	B-Application
.	O
</s>
<s>
Subjective	B-Device
Comparison	O
of	O
Modern	O
Video	B-Application
Codecs	I-Application
Scientifically	O
accurate	O
subjective	B-Device
comparison	O
using	O
50	O
experts	O
and	O
SAMVIQ	O
methodology	O
2006	O
Feb	O
.	O
DivX	B-Application
6.0	O
,	O
Xvid	B-Algorithm
1.1.0	O
,	O
x264	B-Language
,	O
WMV	B-Device
9.0	O
(	O
2	O
bitrates	O
for	O
every	O
codec	B-Application
)	O
PSNR	O
via	O
VQM	O
via	O
SSIM	B-Algorithm
comparison	O
was	O
also	O
done	O
MPEG-2	B-Algorithm
Video	O
Decoders	O
Comparison	O
Objective	O
MPEG-2	B-Algorithm
Decoders	O
comparison	O
2006	O
May	O
.	O
</s>
<s>
bitcontrol	O
MPEG-2	B-Algorithm
Video	O
Decoder	O
,	O
DScaler	O
MPEG2	B-Algorithm
Video	I-Algorithm
Decoder	O
,	O
Elecard	O
MPEG-2	B-Algorithm
Video	O
Decoder	O
,	O
ffdshow	O
MPEG-4	O
Video	O
Decoder	O
(	O
libavcodec	B-Language
)	O
,	O
InterVideo	O
Video	O
Decoder	O
,	O
Ligos	O
MPEG	O
Video	O
Decoder	O
,	O
MainConcept	B-Algorithm
MPEG	O
Video	O
Decoder	O
,	O
Pinnacle	O
MPEG-2	B-Algorithm
Decoder	O
Objectly	O
tested	O
(	O
100	O
times	O
per	O
stream	O
)	O
decoders	O
"	O
crash	O
test	O
"	O
(	O
test	O
on	O
damaged	O
stream	O
like	O
scratched	O
DVD	O
or	O
satellite	O
samples	O
)	O
Codecs	O
comparison	O
Personal	O
subjective	B-Device
opinion	O
2003	O
Nov	O
.	O
3ivx	B-Algorithm
,	O
Avid	O
AVI	O
2.02	O
,	O
Cinepak	B-Algorithm
,	O
DivX	B-Application
3.11	O
,	O
DivX	B-Application
4.12	O
,	O
DivX	B-Application
5.0.2	O
,	O
DV	O
,	O
Huffyuv	B-Algorithm
,	O
Indeo	B-Algorithm
3.2	O
,	O
Indeo	B-Algorithm
4.4	O
,	O
Indeo	B-Algorithm
5.10	O
,	O
Microsoft	O
MPEG-4	O
v1	O
,	O
Microsoft	O
MPEG-4	O
v2	O
,	O
Microsoft	O
RLE	O
,	O
Microsoft	O
Video	O
1	O
,	O
XviD	B-Algorithm
,	O
3ivx	B-Algorithm
,	O
Animation	O
,	O
Blackmagic	O
10-bit	O
,	O
Blackmagic	O
8-bit	O
,	O
Cinepak	B-Algorithm
,	O
DV	O
,	O
H.261	B-Algorithm
,	O
H.263	B-Algorithm
,	O
Motion-JPEG	O
,	O
MPEG-4	O
Video	O
,	O
PNG	O
,	O
Sorenson	O
Video	O
,	O
Sorenson	O
Video	O
3	O
Sometimes	O
comparison	O
is	O
short	O
(	O
up	O
to	O
one	O
text	O
line	O
per	O
codec	B-Application
)	O
Evaluation	O
of	O
Dirac	B-Application
and	O
Theora	B-Algorithm
Scientific	O
paper	O
2009	O
Mar	O
.	O
</s>
<s>
Dirac	B-Application
,	O
Dirac	B-Application
Pro	O
,	O
Theora	B-Algorithm
I	O
,	O
H.264	B-Application
,	O
Motion	O
JPEG2000	O
(	O
the	O
tested	O
codecs	O
are	O
from	O
Q2-2008	O
)	O
Quite	O
detailed	O
comparison	O
of	O
software	O
available	O
in	O
Q2-2008	O
;	O
However	O
,	O
a	O
buggy	O
version	O
of	O
ffmpeg2Theora	B-Library
was	O
used	O
VP8	B-Algorithm
versus	O
x264	B-Language
Objective	O
and	O
subjective	B-Device
quality	B-Device
comparison	O
of	O
VP8	B-Algorithm
and	O
x264	B-Language
2010	O
Jun	O
.	O
</s>
