[theora] No quality advantage with two-pass?

[David Kuehling]

>>>>> "Remco" == Remco  <remco47 at gmail.com> writes:

> The ffmpeg2theora chapter[1] of the Theora Cookbook says that the only
> advantage of two-pass encoding is that you can hit a specific target
> size. But isn't it so that you can reserve bits for difficult parts of
> a video, which improves the perceived quality? 

Why would it have to reserve bits, if you specified a constant target
quality for encoding?  It just takes as much bits as are needed to hit
the configured quality.  In "difficult parts" it will just naturally use
more bits.

> Theora does quite alright without two passes, but it seems like a
> no-brainer to me that two passes will always be better.

You mean, because it takes twice as long to encode?  

Disclaimer: I wrote that part of the Cookbook :).  If I'm really wrong,
just fix that part, floss-manuals works like a wiki.

cheers,

David
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