FfmpegandAudio

The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

Audio transcoding with ffmpeg

transcode to mp3

ffmpeg -i in_file.aiff -acodec libmp3lame -ab 128k out_file.mp3

transcode to ogg

ogg/Vorbis audio files (Vorbis codec; ogg file-format) are quite important, not only it is an open-source format, but also firefox requires ogg format in its <audio> Quality seems quite good (better than mp3 when compressed from a uncompressed audio format: flac, wav or aiff, so it says)

ffmpeg -i input.mp3 -acodec libvorbis -ab 128k output.ogg

explained:
- -acodec libvorbis use vorbis codec
- -ab 128k convert output to 128kbits/sec bit-rate alternatively can use -aq 60 which means audio quality is 60 (~160 kbits/sec)

good information on ffmpeg transcoding: http://howto-pages.org/ffmpeg/#basicaudio

Here is a small script to turn all the .mp3 on the directory to .ogg

#! /bin/sh

ext=".mp3"
target="ogg"
 
for n in *.mp3
do
base=$(basename $n $ext) #to extract only the filename and NOT the extension
ffmpeg -i $n -acodec libvorbis -ab 128k $base.$target 

done
#Script ends here

Adding metadata to mp3 files

unfortunately metadata doesn seem possible to be added to ogg files with ffmpeg

ffmpeg -i infile.mp3 -metadata author="the author name" -metadata title="the title" -acodec copy outputfile.mp3

#! /bin/sh

# adds metadata to all .mp3 files of the directory the script is located
# it employs the file name as the song's title 

ext=".mp3"
 
for n in *.mp3
do
base=$(basename $n $ext) #to extract only the filename and NOT the extension
ffmpeg -i $n -metadata author="YOUR NAME" -metadata title=$base -acodec copy $base$ext

done

Source: http://wiki.multimedia.cx/index.php?title=FFmpeg_Metadata ffmpeg and metadata