OT: Update on Divx

[paulw]

If any one is interested in the Divx codec . below is the body of an email I have recieved

==> Exclusive News :
- Project Mayo Unleashes "OpenDivX"


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Exclusive News
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Project Mayo Unleashes "OpenDivX"


"OpenDivX" is the mothership of all Project Mayo projects. This is an Open
Source project that at it's core will consist of a compliant MPEG-4
natural video encoder and a decoder. There are also other projects that
are springing up under the OpenDivX roof. Including "The Playa" Which is
an open source player for DivX. It includes advanced features like
progressive download (unlike the old DivX ;-)) and plays "broken" or
uncompleted video files. The first version will be on Windows but they are
also planning Linux and Mac versions.

The encoder "Encore"


Is the core - that part of the codec that encodes video from uncompressed
RGB bitmaps into a DivX video bitstream. Its API is defined in encore.h.
The API is essentially a frame-in, frame-out scheme; you give it a RGB
frame and it comes back to you with a chunk of encoded bitstream. "Encore"
is truly independent of any other code. It does not need any system calls
for its operation.

The decoder "Decore"


Is our decoder core - that part of the codec that decodes video from DivX
video bitstream into uncompressed RGB bitmaps. Its API is defined in
decore.h. The API is another frame-in, frame-out scheme, you give it a
chunk of OpenDivX bitstream and it comes back to you with an uncompressed
RGB frame. Like "encore", "decore" is truly independent of any other code,
making no system calls.


"Decore" is a decoder compliant with MPEG-4 natural video, simple profile.
It also incorporates a video postprocessor which hides many of the
artifacts inherent in low bit-rate video.


HERE ARE SOME CURRENT FACTS
- The OpenDivX encoder can achieve near DVD quality MPEG-4 video at 10% to
20% of the original MPEG-2 DVD file size. Yes, we know this is same as
DivX;-), but we have to state it for the newbies.
- OpenDivX has slightly better low motion and still image detail than
DivX;-).
- OpenDivX has brighter whites and blacker blacks than DivX;-).
- OpenDivX detects scene changes automatically and inserts I-frames. In
the DivX For Windows project, this has been translated to Windows key
frames so scrolling is possible in Windows Media Player.
- OpenDivX has better overall image quality without post-processing than
DivX;-) without post-processing.
- OpenDivX has equal or slightly smaller file sizes (1% to 5%) than
DivX;-) for low motion scenes.
- OpenDivX encoder has not been optimized for speed currently at 1.5 fps
to 2 fps on Pentium III 700MHz. The current implementation focus was on
image quality, not speed.
- OpenDivX is ultimately bound by some limitations of the MoMuSys code on
which it was based. The plan is to optimize and fine tune the existing
encoder as much as possible and design and build a new encoder from the
ground up in parallel. Yes, we know the MoMuSys code is messy and
unoptimized but look at what we’ve done with that ugly duckling.
- Current postprocessing includes an adaptive filter that greatly reduces
block-edge artifacts with little or no degradation of the image content.
- The OpenDivX decoder is a pure in-house implementation that is MPEG-4
compliant.
- The decoder can decode around 81 fps on an Intel Pentium III 700MHz PC
without postprocessing. With postprocessing, the rate is approximately 52
fps. These numbers are achieved even without full optimization of the
decoder.
- Additional postprocessing capabilities such as deringing will be added.
However, even without deringing, we feel that the current decoder image
quality is very good.


OpenDivX Now... DivXDeux later.


OpenDivX is the core software that, when ready, will be compiled into
official DivX releases. DivXDeux is the next generation of DivX, and is
actively being worked on in within the OpenDivX project. When the code
good enough, we will christen it DivXDeux and release it.

ProjectMayo Homepage: http://www.projectmayo.com/
OpenDivX Encoder: http:/www.projectmayo.com/win/files.php
OpenDivX Encoded Example: http://www.projectmayo.com/showcase/index.php
OpenDivX Forums: http://forums.projectmayo.com/index.php
OpenDivX License:
http://www.projectmayo.com/opendivx/...icense_v10.txt


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THANK YOU! PLEASE KEEP A LOOK OUT FOR YOUR NEXT ISSUE!
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[Prospero]

Not to shabby for a codec not finished yet. I may switch to it from mpeg4v2 when it's finished. For grins here is a still of my test run. Source HuffYuv rendered to opendivx at 1000kbps.



Oh, only filter used was smart deinterlace.

[This message has been edited by Prospero (edited 17 January 2001).]

[absalom]

This thing is slow, not that I'm complaining. But after frameserving, cropping, and resizing the encoders average fps of 2 is easily decimated to a halt. I could spend days using this to encode when I could use wm8 (also slow) or m4c + divx and acheive similar quality. But I will give them credit for actually coming out with something that is actually tangible and not a few bytes hacked from the original M$ codec. It has potential...

[This message has been edited by absalom (edited 18 January 2001).]