I'm thinking of writig a new hack of Nandub, which would allow you to use it with DivX 5, via Logfile editing (Thus allowing you to use B-Frames, and hopefully GMC/Qpel). This would allow you to use Nandub's superiour bitrate control, while also letting you use DivX 5's better compression and motion compensation. Would anyone actually use this?

I think it is a great !!!
I use Nandub a lot and is like 2 know how DivX v5 is with Nandub..

start writing

That indeed would be very good ... What do you mean you havent started it yet ) j/k

I've got a few ideas going. Unfortunately, the only one that I've got that would be possible for a human to manage as of yet would require 5 passes (although one of them should go very quickly), using 3 different programs. I have also yet to find a patching algorithm that makes DivX stick to the quantitizers I want it to. For some reason quant isn't having the effect I thought it would, but please do your own tests. I'm thinking that complexity's gonna help the most. Could someone do some tests, on any clip, but with log files with things like:


Frame 1 intra 1, quant 0, texture 0, motion 0, total 0, complexity 0
Frame 2 intra 0, quant 0, texture 0, motion 0, total 0, complexity 10000
Frame 3 intra 0, quant 0, texture 0, motion 0, total 0, complexity 20000
Frame 4 intra 0, quant 0, texture 0, motion 0, total 0, complexity 30000
Frame 5 intra 0, quant 0, texture 0, motion 0, total 0, complexity 40000
Frame 6 intra 0, quant 0, texture 0, motion 0, total 0, complexity 50000
Frame 7 intra 0, quant 0, texture 0, motion 0, total 0, complexity 60000
Frame 8 intra 0, quant 0, texture 0, motion 0, total 0, complexity 70000
Frame 9 intra 0, quant 0, texture 0, motion 0, total 0, complexity 80000
Frame 10 intra 0, quant 0, texture 0, motion 0, total 0, complexity 90000
Frame 11 intra 0, quant 0, texture 0, motion 0, total 0, complexity 100000
Frame 12 intra 0, quant 0, texture 0, motion 0, total 0, complexity 110000,

And see how it affects the analyse.log that DivX produces?
Note: For a log like the one above, it must have no scene changes.

Could someone please extend the AVI specs, so that B-frames can be marked properly? And so, that linear decompression of vcm doesn't cause a codec-delay anymore?

Okay, I've found a few promising code sections. Most notably:

VideoSequenceCompressor::getFrameInfo
VideoSequenceCompressor::SetCompressionLevels
VideoSequenceCompressor::SetKFQuality
The Big Cahuna:
VideoSequenceCompressor::packFrame
VideoSequenceCompressor::packFrame2

VideoSourceAVI::getFrameQuant

I will look into these once I have time.

And no one wants to help me with logfiles?

I will also need a few beta testers (who are relatively proficient Nandub encoders. No: "I don't know it, but I am willing to learn!". Sorry.), and even better: someone to help finding the vital code section, and getting it to accurately set the quantitizer.

i'd like to be a beta tester....