[FFmpeg-devel] [PATCH] metadata conversion API

Peter Eszlari peter.eszlari
Sun Mar 1 14:28:44 CET 2009

2009/3/1 Baptiste Coudurier <baptiste.coudurier at gmail.com>:
>>> Also I believe this would simplify adding support for libx264
>>> commandline switches in libx264 wrapper, since you do not needed an API
>>> extension in AVCodecContext, for it due to x264_parm_parse which takes
>>> exactly 2 char *. This is what I call generic API.
>> the question is if we _WANT_ to let a encoder bypass the normal way to
>> pass parameters.
> I do. Is anybody against this ?

Wasn't the topic "codec-specific options" discussed years ago and
rejected with the argument "code duplication"?
As a user I'm very much in favor of codec-specific options (not only
for wrappers).

2009/3/1 Baptiste Coudurier <baptiste.coudurier at gmail.com>:
>> If the awnser to this is yes, its a matter of a single char* generic_param
>> in AVCodecContext with which encoders can do what they want.
> Encoders will doxygen the parameters it supports when declaring it.
> For libx264 we would point to libx264 documentation of course.
> Btw, it would be good to know which option encoder honors, currently
> user do not know this. This is not practical IMHO.

Not only does the user not know about it, ffmpeg/lavc too doesn't know about it.
If I do the following:

$ ffmpeg -i file.avi -aq 50 file.mp2

The option "-aq" gets silently ignored, while one would expect an
error massege like "option -aq not supported by ffmp2".

More information about the ffmpeg-devel mailing list