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DivX v5.1 released

Written by Petteri Pyyny (Google+) @ 03 Sep 2003 3:30 User comments (3)

DivX v5.1 released After a series of beta versions, DivXNetworks has finally launched DivX v5.1 which, the company claims, is the "biggest improvement yet" in DivX's history. The changelog seems pretty impressive...
What's new:
  • Added a new high-quality psychovisual mode that includes the following features:
    • Texture cortex masking and rate distortion algorithm
    • Hybrid mode (with texture cortex masking)
      peed optimization
    • Chroma operation (this option is not enabled by default for performance reasons; to enable it, create an empty file in C:\ called "DivxPvShapingChroma.txt" for "fast" mode and "DivxPvSimpleChroma.txt" for slow mode; testing shows only 1-2% gains in JND tests)
  • The decoder has been rearchitected and is now 10 to 30% faster on all CPU platforms.
  • The decoder now supports automatic post-processing during video playback.
  • Added new features to the rate control modes of the encoder, including:
    • A complexity vector log file
    • An API that allows real-time control of rate control
    • An API that allows forced I-frame insertion

  • Redesigned encoder GUI. The new GUI is more accessible and simplifies overall usage.
  • DivX 3 compatibility. (There were no problems detected on any of the more than 60 hours of test content.)
  • Performance of Nth Pass strategy planning performance.

  • A bug that caused the quantizer to overshoot the bitrate following a transition to a complex scene.
  • A bug that limited the interframe change in quantizer to the ideal quantizer or plus or minus 2.
  • A bug in RGB32 to YUV conversion on Pentium 4 machines.
  • A minor bug that affected multiple CPU configuration.
  • A bug with the rate control video buffer verifier (VBV) that would enforce a "3 sec" max bitrate.
  • Several bugs that affected Nth Pass encoding strategy planning.
  • A bug that caused a different number of frames to be reported between different passes in VirtualDub.
  • A bug that caused motion vector (MV) reuse to be non-functional.
  • A bug that caused problems when MV reuse and psychovisual mode were used together.
  • Several bugs with the installer.
  • A bug that caused a crash when setting crop/resize values.

You can download the free version of DivX v5.1 from here:

More information:

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3 user comments

13.9.2003 15:36

Actually, I downloaded the DiVX v.5.1, and the quality and colour decreased, when compared to the version before. I'm gonna restart to see if it's just my computer....

Everyone is entitled to their own true opinion. Either respect that or don't.

25.10.2003 4:35

The rate distortion algorithm that is used when the preformance of the divx 5.1 encoded is set to slowest is drastically slower than the slowest encoding in divx 5.05. Encode time with the divx 5.1 codec can be about 12 times longer than 5.05. The standard mode (in quality vs prefomance setting) in the divx 5.1 is equivalent to the slowest setting in divx 5.05. IMHO the difference between a 2 hour encode and a day long encode for a small amount of quality increase is not worth it. Athough with a version of the divx encoder that supports the new 64-bit processors, the encode time will hopefully be drastically faster and allow for significantly smaller file sizes without comprimising quality using the slowest setting of the divx 5.1 encoder.

37.10.2003 18:38

I had a crack at it with the new 5.1 codec and the movie I was backing went out of sync with the sound after 1hrs playback. maybe that was cos I pushed the pause button too much or something. I'm going to have another go at it.


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