Re: [Audacity-devel] Why no wma write?

[Markus M. <me...@me...>]

Dominic wrote:

> Using one of these tools to decode WMA would be great if we could do
> it without legal issues.  Definitely worth investigating if someone's
> interested.

Matt wrote:
> On Windows, we could also allow Audacity to use the Windows Media SDK to
> encode and decode WMA, as long as all the necessary files qualify under
> the "normally distributed with the operating system" clause of the GPL
> section 3 (I'm not sure whether they do).

I don't think we should have any legal issues here. First, the API for
encoding and decoding audio files has come standard with Windows for a
long time, and there should also not be any patent issues with it.
What's different are the codecs, which come with, e.g. Media Player or
are separate downloads. On the other hand it's kind of like it also is
with printer drivers: You just let the operating sytem enumerate the
number of devices (i.e. filters/codecs) it has installed and let the
user choose one. The interface is the same whether you're writing to a
WAV file, to a WMA file or to some other evil patented format which
isn't even known at the time of writing. Because support for codecs is
essentially a plugin interface, the program(mer) cannot know which
codecs the user may have installed and what are the license / patent
issues with it - if at all, that's the responsibility of the user.

For political reasons, I do agree with Dominic that we should not have
any write support for WMA, though. On the other hand, if we think about
how that would be not legal, then we should also worry about how we are
currently handling MP3 support with LAME: one could agree that using an
interface that's built into the OS for writing, say, WMA files should
certainly be more legal than using some unlicensed MP3 encoder from the
Internet of which the legality has regularly been questioned by the
patent holders...

Reverse engineering is of course a totally different story; see also the
following article about how VirtualDub authors were stopped from having
ASF-support:

http://www.advogato.org/article/101.html


Markus