Hi friends,

I have just read the official DivX 5.1 Guide and stumbled over two suggestions for a multipass encoding (keep in mind that a multipass encoding should only refine rate control strategy).


Suggestion 1:
Use Slowest P/Q mode only in final pass (Standard P/Q mode in previous passes).

Personal comment:
Slowest P/Q mode resp. its Rate-Distortion algorithm should have great impact on rate control strategy. Why isn't it advised to use this algorithm for second-last and final pass? Doesn’t RDA more do a refining of the rate control strategy for the next pass? (when using it in final pass only it has the effect of a 1-pass, doesn’t it? So it would require another pass to effectively take advantage of the RDA using the multipass log...)


Suggestion 2:
Use Psychovisual Enhancements only from second-last pass onwards.

Personal comment:
Wouldn’t it be enough to enable the Psychovisual Enhancements in final pass only? As far as I understand PVE it only reallocates bits for each frame individually and doesn’t have the least impact on rate control strategy so it cannot screw it up.


Any opinions and corrections are welcome, thanks.

I would recommend you to read the Doom9's guide on DivX 5 encoding: http://www.doom9.org/gknot-main3.htm Do what it tells you to do. Xvid also worth trying.

Hi Latexxx,

well, I know exactly what to do . The only two questions that are left at the moment are the two above. I just want to understand the suggested settings, why it is not highly recommended to use RDA in second-last pass as well and why using PVE in last pass isn't enough.

Thanks anyway.

1. It isn't advertised to use the Slowest P/Q for the last two passes because it's slow and there is very little quality improvement.

2. PVE on the last pass is enough, you don't need to do it for the last two.