[Libav-user] Ask about license for using ffmpeg library in binary

[Carl Eugen Hoyos]

Khanh Nguyen Nam <nnkhanh at ...> writes:

> I am developing an application which uses ffmpeg library as below:
>     
> Add ffmpeg binary to application source code
> Call ffmpeg command line via C# code.

If you want to distribute a software binary that is FFmpeg (or a 
derivative work of FFmpeg) and you are not using any GPL'd parts of 
FFmpeg, then you have to comply with the LGPL (or a compatible 
software license like for example the GPL).
If you want to distribute a software binary that is FFmpeg (or a 
derivative work of FFmpeg) and you are using GPL'd parts of FFmpeg, 
then you have to comply with the GPL (is is not sufficient to 
comply with the LGPL in that case).
Please read http://ffmpeg.org/legal.html and do not forget to 
read either the GPL or the LGPL depending on which parts of 
FFmpeg you plan to use.

Please understand that while you are very welcome to support the 
FFmpeg development (even financially), there is no way you could 
"pay" for FFmpeg (at least in the sense I understand your 
question). And please understand that you have to comply 
with the GPL (or the LGPL, see above) no matter if you sell your 
software or give it away for free.

Carl Eugen