Re: [gentoo-user] Re: libav/ffmpeg's bitrate options have no effect in Gentoo

[Michael Mol <mikemol@gmail.com>]

On Tue, Sep 6, 2011 at 8:34 AM, Casper Ti. Vector
<caspervector@gmail.com> wrote:
> On Tue, Sep 06, 2011 at 03:09:13PM +0300, Nikos Chantziaras wrote:
>> So try with avconv instead.  But for MP3, you should probably be using
>> LAME with a VBR quality setting instead.
> In fact I don't quite know what you mean in this sentence :|

'lame' is an MP3 encoder. VBR is 'variable bitrate', which means that
high-information sections in the input stream get more bits in the
output bitstream, and low-information sections in the input stream get
fewer bits in the output bitstream. An encoded song might use 192Kb/s
for a few seconds, and then 32Kb/s for a second, and jump up to
256Kb/s for a quarter-second before dropping down to 128Kb/s--but
still sound to your ear like it was encoded at a constant bitrate of
256Kb/s. All so that audio fidelity is maintained when there's
something there to actually hear.

Or, more simply:
* 'lame' is an MP3 encoder
* 'VBR' stands for 'variable bitrate', and offers a better
size/quality tradeoff scale than saying "I want 192Kb/s"

-- 
:wq