If you use MAD as a DLL (not sure about the COM object), you have to

distribute

your product under the GPL, too. This is not the Library (or lesser) GPL!

The

same is for static linking.

The complete license can be found under http://www.gnu.org/copyleft/gpl.html

Aha, I see there:

"... If identifiable sections of that work are not derived from the Program, and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works. "

So I need to make my sure the non-MAD part is

- identifiable as sections of that are not derived from MAD - reasonably considered as an independent and separate work in itselve

Part 1 is no problem. Part two is a problem when I link statically, even if I give that one source-file free.

This means I do have to use my seperate source-file that uses MAD, as a independant module (DLL or even its own COM object as they did with LAME), which I need to make completely GPL too. I can link MAD statically in that DLL of course. That takes care of the 'seperate' part.

And if the setup of that MAD-module object (DLL or COM or whatever) is generic enough to be considerred 'independant' from my COM object (in the sence that it is not *just* created for my own COM object), I don't have to give the COM source-code free. This shouldn't be that hard since I'm planning on re-using this MAD-based module in several other completely different projects too.

So no static linking. ;-(

I always thought MP3pro is backward compatible?

It is, but MAD identifies the bitrate incorrect in some cases. So it is a MAD problem. It is a comon problem that other decoders sometimes also have.

Regards,

Armin