I've been looking for a way to convert an mp3 to aac programmatically or via the command line with no luck. Ideally, I'd have a snippet of code that I could call from my rails app that converts an mp3 to an aac. I installed ffmpeg and libfaac and was able to create an aac file with the following command:
ffmpeg -i test.mp3 -acodec libfaac -ab 163840 dest.aac
When i change the output file's name to dest.m4a, it doesn't play in iTunes.
Thanks!
FFmpeg provides AAC encoding facilities if you've compiled them in. If you are using Windows you can grab full binaries from here
ffmpeg -i source.mp3 -acodec libfaac -ab 128k dest.aac
I'm not sure how you would call this from ruby.
Also, be sure to set the bitrate appropriately.