[FFmpeg-user] GPL'd libfaad2 support when compiling without --enable-gpl ?(correct)

[littlebat]

On Thu, 20 Oct 2011 10:01:36 +0200
Ewald Peiszer <ewald.peiszer at gmx.at> wrote:

>  > "2".  Current versions of ffmpeg *decode* AAC internally.  Try
>  > "ldd 
> $(which ffmpeg)"
> 
> Thanks Phil!
> 
> Two more things:
> 
> 1) Are there notable/known quality differences between the internal
> AAC decoder and libfaad2 library in terms of system ressources, audio 
> quality and stability/reliability?
> 
> 2) the output of ldd does not show any references to an external mp3 
> decoder library so I assume that the same is true for mp3 decoding?
> 
>   linux-vdso.so.1 =>  (0x00007ffff83fe000)
>          libavformat.so.1d => /usr/lib/libavformat.so.1d 
> (0x00007f58efdb9000)
>          libavcodec.so.1d => /usr/lib/libavcodec.so.1d
> (0x00007f58ef77e000) libavutil.so.1d => /usr/lib/libavutil.so.1d
> (0x00007f58ef575000) libm.so.6 => /lib/libm.so.6 (0x00007f58ef2f4000)
>          libpthread.so.0 => /lib/libpthread.so.0 (0x00007f58ef0d8000)
>          libc.so.6 => /lib/libc.so.6 (0x00007f58eed76000)
>          libz.so.1 => /usr/lib/libz.so.1 (0x00007f58eeb5f000)
>          libogg.so.0 => /usr/lib/libogg.so.0 (0x00007f58ee95a000)
>          libdc1394_control.so.13 => /usr/lib/libdc1394_control.so.13 
> (0x00007f58ee74a000)
>          libdl.so.2 => /lib/libdl.so.2 (0x00007f58ee546000)
>          libgsm.so.1 => /usr/lib/libgsm.so.1 (0x00007f58ee339000)
>          libtheora.so.0 => /usr/lib/libtheora.so.0
> (0x00007f58ee0f5000) libvorbis.so.0 => /usr/lib/libvorbis.so.0
> (0x00007f58edec9000) libvorbisenc.so.2 => /usr/lib/libvorbisenc.so.2 
> (0x00007f58edaef000)
>          /lib64/ld-linux-x86-64.so.2 (0x00007f58f0040000)
>          libraw1394.so.8 => /usr/lib/libraw1394.so.8
> (0x00007f58ed8e9000)
> 

"./configure --list-decoders" will list all available decoders, include
internal and external. You will see only "aac" decoder exist even if
you install "libfaad*" and "libfaad*-dev" or some things similar.

"./configure --list-encoders" will list all available encoders.

"ffmpeg -codecs" will list all available codecs(include decode and
encode) supported by your ffmpeg binary.