Re: [rtcweb] x264 vs OpenH264 (Was: On the topic of MTI video codecs)

[Daniel-Constantin Mierla <[e-mail]>]

On 11/1/13 6:21 PM, Olle E. Johansson wrote:
> On 01 Nov 2013, at 18:03, Daniel-Constantin Mierla <[e-mail]> wrote:
>
>> On 11/1/13 5:35 PM, Max Jonas Werner wrote:
>>> On 01.11.2013 17:24, cowwoc wrote:
>>>> On 01/11/2013 12:19 PM, Emil Ivov wrote:
>>>>> It would be nice for Mozilla to comment then. They wouldn't have been
>>>>> required to statically link against it or even distribute it. It is
>>>>> already possible to use GPL plug-ins with Firefox, so why is x264 an
>>>>> insurmountable problem?
>>>> Can I dynamically link x264 against my proprietary application without
>>>> having to GPL it?
>>> Actually no: https://www.gnu.org/licenses/gpl-faq.html#LinkingWithGPL
>>>
>>> That's why the LGPL (that poses other risks, though) exists.
>> GPL constraints about open sourcing are for the case when distributing the application. You can link anything you want with gpl code and you don't have to make the sources available if you don't distribute your application.
>>
>> I think that Emil wanted to say that we, users, don't distribute web browsers, we just use them.
>>
>> Then, if I got it right, no browser will link against the h264 plugin. That will be loaded at user will (eventually), by downloading on demand from cisco site.
>>
>> So I, as user, I take Firefox from Mozilla site, then when I need to do webrtc, my browser will download (first time) and use the h264 plugin. Because I don't distribute further the two, I don't see any restriction from gpl here. That's my understanding.
> I don't think GPL agrees with that. GPL applies at runtime, not only when building the app. THe FAQ on the link above says
>
> "Linking ABC statically or dynamically with other modules is making a combined work based on ABC. Thus, the terms and conditions of the GNU General Public License cover the whole combination."
>
> "If the program dynamically links plug-ins, and they make function calls to each other and share data structures, we believe they form a single program, which must be treated as an extension of both the main program and the plug-ins. This means the plug-ins must be released under the GPL or a GPL-compatible free software license, and that the terms of the GPL must be followed when those plug-ins are distributed.

Again, the key term here is distribution. I, as user, I don't distribute 
them. Mozilla, as developer, doesn't link against h264 plugin nor 
distributes it. Same with cisco, they don't link h264 plugin against 
firefox, nor distribute firefox.

Now, I, as a user, mix the two, which may result in a combination that 
has to be gpl (if plugin or browser is gpl), but only in my house. So, 
as long as I keep it here, don't give the two combined away, no GPL can 
be enforced.

I agree a specialized lawyer can be more accurate and my understanding 
of GPL might not be the best one. But if it is what you say, I have a 
dozen a folks I know they have private modules for Kamailio, Asterisk 
and other GPL project. We will have lots of features in the next 
releases if we can force them to publish their extensions though GPL :-)

Daniel

>
> If the program dynamically links plug-ins, but the communication between them is limited to invoking the ‘main’ function of the plug-in with some options and waiting for it to return, that is a borderline case."
>
> /O

-- 
Daniel-Constantin Mierla - http://www.asipto.com
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