DTS or AC3 to AAC Options

[141077]

Hello there!

I'm from Germany so please excuse me if my english isn't very well. I currently work on something for my university. I'm gonna right down the process of converting an HD .mkv file to an iTunes friendly .m4v. The goal will be to have a file at the end which can be played on most Apple devices. So when there's one 5.1 audio track as a DTS or AC3 file in the mkv I want to have one 5.1 AAC audio track and one in stereo for the mobile devices. In the last two days I've been looking around for the best options and encoders in this forum and in the wiki, but I'm not quite sure what to use and what's even more important: why I should use that?

For this process I'll use a mac. I've read that the Nero Encoder give the best results but since it doesn't excepts .dts or .ac3 files I don't know what I could do. Should I convert the .dts file f.e. first into another format so that NeroAAC would recognize it? Wouldn't that mean a loose of Quality? That's by the way also a very important thing for my work. To know what would be the best options in the encoder and to know how big the quality loss could be etc.

I hope you can point me into some directions and tell me something relevant for my topic. Have a good night everyone!

[mixminus1]

Well, first off, you say you're using a Mac, but then say you want to use Nero's AAC encoder, which is only available for Windows - so, which is it?

The only utility for OS X that I'm aware of that might be able to do what you want in one step is ffmpegX, but I haven't used it in quite some time as it was always very buggy when I tried to use it.

Can you run WINE, i.e. Windows under OS X? If so, eac3to might be able to do pretty much exactly what you want very easily (and reliably!). I say "might" as I've never tried it under WINE. However, eac3to is essentially a stand-alone program, so it seems like it would be a good candidate for successful operation under WINE.

It can decode any surround format (although I think it still may have some channel-mapping issues with 7.1 DTS-HD, not sure), can output multichannel or stereo mixdown, and can easily pipe to neroAacEnc.exe for on-the-fly AAC encoding.

The only caveat is that I don't think it can output multichannel and stereo AAC files simultaneously - you'll have to do two encodes for each source file, or launch parallel instances (which should work, but I've never tried it).

This post has been edited by mixminus1: Nov 1 2011, 19:37