On Wed, 11 Jul 2012, Luca Barbato wrote:
On 07/11/2012 02:38 PM, Martin Storsjö wrote:
For enabling VBR, the general consensus seems to be to use the
qscale flag. There doesn't seem to be any consistent way to
indicate the actual desired quality though. Both libfaac and
libmp3lame calculate avctx->global_quality / FF_QP2LAMBDA and set
that as the libraries' VBR quality parameters, with wildly different
results. On libmp3lame, the VBR quality parameter is between 0 (best)
and 10 (worst), while the scale goes in the opposite direction for
libfaac, where higher quality values gives you better quality.
Therefore, for now, I just pass the actual value of
avctx->global_quality through. You can set it to values between 1
and 5:
1 - about 32 kbps/channel
2 - about 40 kbps/channel
3 - about 48-56 kbps/channel
4 - about 64 kbps/channel
5 - about 80-96 kbps/channel
---
Looks fine, just should we mark it non-free or not?
That's the big question, IIRC j-b and Diego had differing views on how to
interpret it.
// Martin
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