AC3 to AAC

[JasonKerner]

I have an 5.1 AC3 file extracted from an MKV file. I also have the original MKV available if that helps. What I want to be able to do is convert the 5.1 AC3 into a six channel (5.1) AAC file. What do I need to put ffmpegX on to to make this work?

Cheers

Jason

[Case]

ffmpegX does convert audio files to mp2, mp3 and ac3 as audio-only formats. Not to AAC.
Currently, ffmpegX movie conversions with AAC audio are mono or stereo, not 5.1.

To convert your MKV to MP4 with 5.1 AAC sound, you could use the VLC Streaming/Exporting Wizard.
To convert a DVD or VOB to MP4 with 5.1 AAC sound, you could use HandBrake.
To convert an AC3 5.1 file to AAC 5.1, you could export in QuickTime Pro to AIFF multichannel, then convert that to .mov with AAC 5.1 audio.

You can get Dolby Digital passthrough (optical port) on your Mac (Quicktime, VLC or Front Row), just like with DVDs, if you install Perian and do this modification. This trick is not for AppleTV, though.