[FFmpeg-devel] [PATCH v2] avcodec/nvenc: Include NVENC SDK header

[Andreas Cadhalpun]

On 12.12.2015 13:27, Philip Langdale wrote:
> On 2015-12-12 19:26, Andreas Cadhalpun wrote:
>> Anyway, I think your idea about a license exception would be a good solution.
>> We could add a special exception to nvenc.c, allowing its use with Nvidia's
>> blobs, something like [1]:
>>
>>  In addition, as a special exception, the copyright holders give you
>>  permission to combine this code with free software programs or libraries
>>  that are released under the GNU LGPL and with code included in the standard
>>  release of the CUDA and NVENC libraries under the NVIDIA Software License
>>  (or modified versions of such code, with unchanged license).
>>  You may copy and distribute such a system following the terms of the GNU LGPL
>>  for this code and the licenses of the other code concerned.
>>
>>  Note that people who make modified versions of this code are not obligated
>>  to grant this special exception for their modified versions; it is their
>>  choice whether to do so. The GNU Lesser General Public License gives
>>  permission to release a modified version without this exception; this
>>  exception also makes it possible to release a modified version which carries
>>  forward this exception.
> 
> This is fair enough,

OK.

> but I want to close out the LGPL conversation. The FAQ
> specifically discusses GPLv2 and GPLv3 and not LGPL, and I'll claim that's because
> it doesn't apply.

I'll claim that's because the text for the LGPL would be mostly duplicated.

> The fact that a third party can take LGPL ffmpeg and combine it
> with proprietary code in certain ways means that clearly we can do so as well.

No, because the LGPL allows this only for a "program that contains no derivative of
any portion of the Library". Otherwise anyone could just add proprietary code
to FFmpeg, distribute that and claim it is in accordance with the LGPL.

> it
> would be highly illogical to conclude that section 6/7 do not apply to the original
> code itself and that we need to construct a separate entity that does the combination
> for it to be licence compliant.

No, that's not illogical, that's the core component of the LGPL:
It ensures freedom of the library code, while allowing anyone to use the library.

Best regards,
Andreas