Re: Q: two-pass quality encoding

On Sun, 14 Dec 2003, Picasso Pablo wrote:

> Hi there,
> 
> I dont use the two-pass encoding, because AFAIK it tries to keep the
> bitrate fluent - which I dont care about. 

It tries to keep _quality_ constant. 

> What I care about is quality, that's why I use fixed quantizer value.

Fixed Quant != Constant Quality 

but if you like it that way, okay...

> But there is the problem - I have to encode the source twice, trice or
> even more till I get the right number to fit the output file to e.g.
> 700MB. Is there a way how to get this without trying numbers and
> reencoding? (If the encode takes 30 hours as the video I encode right
> now, it is a real burden)

Encode once in bitrate mode, calculate average quantizer, use that in a
second pass. It will not fit perfectly, but it's should be a good
approximation.

gruel