Code review comment for lp:~mixxxdevelopers/mixxx/features_m4a_win7

> Bill: Doesn't Media Foundation allow us to use WMA and other kinds of file types in addition to M4A? If so, how much work would be involved in adding all of them that we don't currently support? What about just WMA/ASF?

Media Foundation supports: http://msdn.microsoft.com/en-us/library/windows/desktop/dd757927(v=vs.85).aspx. It would have the same minimum requirements as the AAC/m4a functionality because all systems having the necessary SourceReader interface also have the AAC decoder (and vice versa). I don't think the amount of work would be overwhelming but as we don't even have a wishlist bug for wma support I don't know that it's worth the time.

> 1) Can we legally distribute the MediaFoundation-using binary without cost or restriction?

Yes, it's the same situation as the Core Audio SoundSource. We're just calling an OS interface. They've paid for the AAC codec.

> 2) Will a Mixxx binary that has it built-in (as opposed to a plugin) still run fine (just without M4A/WMA support) on systems without the required system libraries, such as Windows 2000 & XP?

In short, no. Vista/2008 without the "Platform Update Supplement" and earlier versions of Windows will fail at run-time linking because they're missing either Media Foundation itself or the SourceReader interface. If a system were to exist with the SourceReader interface but not have the AAC decoder, Mixxx would run and simply fail to decode AAC, although I'm not aware of any situations in which this can occur.