[Ffmpeg-devel] [PATCH] Update docs according to new "ab" parameter unit

Benoit Fouet benoit.fouet
Tue Mar 6 11:26:34 CET 2007

Michel Bardiaux wrote:
> Benoit Fouet wrote:
>> Hi,
>> Michel Bardiaux wrote:
>>> Benoit Fouet wrote:
>>>> Hi Takis,
>>> [snip]
>>>> well, if you update this, you have also to change "-b" to "-vb"
>>>> in fact, the behaviour now is that one:
>>>> - "ab" option sets audio bitrate
>>>> - "vb" option sets video bitrate
>>>> - "b" option sets both
>>>> so, if we have on the same line a "ab" option followed by a "b"
>>>> option... the latter will overwrite the former...
>>> Is this *really* what we want? This new meaning for -b will break
>>> *every* example in the archives, every script using ffmpeg,... in a
>>> not-so-obvious way. It might be better to remove with -b entirely.
>> should have been a great idea to have those remarks in the dedicated
>> thread, when i exposed it :)
> Sorry, I was very busy these last days with personal matters. But that
> the change has started should not stop you from changing things again,
> it would not be the first time in the life of ffmpeg!
that's not what i said...

>> i cannot see an easy way to get rid of "b" option, though...
> I didnt see it would be easy. I said it would be less dangerous than
> changing its meaning to have such a brutal effect on the audio rate.
> It would cause use of -b to fail in a clear and understandable way. 
well, if "b" option has to disappear, i guess its use should fail, we
agree on that

> (Well, maybe not so understandable, I thing ffmpeg as it is would
> consider -b as an output file name, correct?)
no, it would fail if it doesn't know the option (output file names
cannot begin by "-")

>> and if you want the same bitrate for audio and video, 
> I dont see that as a frequent requirement.
as i said to M?ns, it could be useful for low res videos, but, well, we
can of course set both audio and video bitrates separatly...

i'm really open... if it is the majority will to get rid of "b" option,
i'll try to do it...


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