Radiomodes & WMA

dinkypumpkin dinkypumpkin at gmail.com
Mon Feb 6 08:46:12 EST 2012


On 06/02/2012 12:34, Kapitano wrote:
> Thank you, for all the answers. My workaround is to download using the
> --raw switch, which gives .flv files, from which I extract the .aac
> using FLV Extract (downloadable here: http://moitah.net/).
>
> For some strange reason I've been unable to find a program which
> *quickly* extracts the sound from a mp4/m4a container.

ffmpeg should be snappy enough.  An unscientific example from my machine 
with a 2-hour 128k audio file: ffmpeg takes 3-4 seconds to extract the 
AAC audio stream from either FLV or MP4 container, whereas flvextract 
take 1-2 seconds to extract audio from FLV.  Not much of a difference. 
Then again, there's no need to create the M4A file if you don't need it.

One esoteric thing to note.  The AAC streams in the M4A files from 
get_iplayer (but not the stream in FLV files from --raw) have been 
passed through ffmpeg's aac_adtstoasc filter to remove ADTS headers. 
This would seem to have no bearing on your setup, but I think some 
players had trouble unless the headers were filtered.




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