Using ffmpeg for BlackBerry Bold playback
Sometimes ffmpeg just doesn’t play like you’d hope it would. I was trying to re-encode video clips for a BlackBerry Bold (the Bold supports H.264 playback) but every encode would have a blank black screen for video, and the audio would be fine (more on audio later).
I’m currently using SVN release r19352 (and also tested with r21566 (2010-01-31)).
ffmpeg arguments for BlackBerry H.264
ffmpeg -v 0 -y -i input.mp4 -f mp4 -aspect 2.409 -vcodec libx264 -vpre default -vpre baseline -s 480x200 -r 24 -b 220k -acodec libmp3lame -ab 24kbit/s -ac 1 output.mp4 |
So lets break down these arguments:
-v 0 = Set verbosity level -y = Overwrite existing file -i input.mp4 = The file you want to convert -f = Force the video type -aspect = The magical number to get the resize right -vcodec libx264 = We're going to use x264 for video codec -vpre default -vpre baseline = Magical presets. And ensure BlackBerry compatibility -s = The final dimensions of the clip -r = Video frame rate -b = Bitrate per second (the larger number the better the video) -acodec libmp3lame = See Audio heading below -ab = Audio bitrate -ac 1 = Number of Audio Channels output.mp4 = The output file |
-vpre isn’t working for me (and I’m on Windows)
ffmpeg isn’t a Windows only application and looks for its presets in /usr/local/share/ffmpeg/ so if you create a folder structure on your Windows computer c:\usr\local\share\ffmpeg\ and copy all the *.ffpreset files into said folder you won’t have problems with -vpre anymore
Audio issues (AAC)
In later releases of ffmpeg AAC (or libfaac) was disabled; I assume due to AAC being patent encumbered. There’s ways around turn libfaac back on, or you could just switch to using libmp3lame or the like.
February 2nd, 2010 at 2:11 pm
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