[mythtv-users] I feel so violated (by Apple)

Jonathan Rogers jonner at teegra.net
Tue Apr 18 07:53:15 UTC 2006

Ivan Kowalenko wrote:
>>   How does VLC, Xine, and MPlayer work
>> without a license?
> Open sourced MPEG-2 decoders, as opposed to the official MPEG-2  
> decoders.

I'm pretty sure that the licensing of copyrights on software, whether 
Free or proprietary is irrelevant to the licensing of patents on various 
technologies related to MPEG-2. My understanding is that holders of 
patents can try to extract license fees from anyone using those patented 
methods to encode or decode video or audio in places where those patents 
are legally enforceable, regardless of the particular software 
implementing those methods.

VLC, Xine, and MPlayer are all programs which include or link to code 
that implements patented algorithms. Though the patent holders can't 
stop the code from being written or distributed, they can try to prevent 
it from being used without licenses. Since extracting fees from all 
users of those media players would probably involve tracking down 
individuals playing DVDs at home or being seen as bullies attacking 
community projects, they don't seem to do that much. Corporate entities 
like Apple, Microsoft, or RedHat are much easier targets, so they have 
to pay license fees to the patent holders or avoid distributing software 
that implements the patented algorithms.

Of course patent law and licensing is extremely complex and I only 
understand a small part of it. I searched for a good explanation of 
patent issues around MPEG-2 and Free Software, but I didn't find one in 
several minutes of searching, though there are FAQs about MPEG audio 
(MP3 specifically), which is only part of the MPEG universe of standards 
and is often not even used with MPEG-2 applications like DVD and ATSC in 
North America.

I did discover that MPEG itself works on technical standards, but 
doesn't involve itself with patents or licensing at all. To implement 
any of their standards probably requires the use of many patents and 
there isn't just one place to go to license them, though there are 
several portfolio aggregators, like MPEG-LA.

Jonathan Rogers

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