[Ffmpeg-devel] overall license review - adding proper license headers

Diego Biurrun diego
Fri Sep 1 17:46:00 CEST 2006

On Fri, Sep 01, 2006 at 11:39:03AM -0400, Rich Felker wrote:
> On Fri, Sep 01, 2006 at 04:13:47PM +0200, Diego Biurrun wrote:
> > libavcodec/fdctref.c claims all rights reserved.  This is non-free.
> > Houston, we have a problem.  Where does this file come from?
> It's the reference implementation. IIRC it's not used and just
> included for people to read but I may be mistaken.


dct-test: dct-test.o fdctref.o $(LIB)

So it's used in dct-test.c, even though it's not used in a default
compile.  Is dct-test still useful?  I have no idea if it even compiles,
it's x86-only...

> > In libavformat/ dv1394.h is marked as GPL while dv1394.c is marked as
> > LGPL.  While this is probably an oversight, this makes FFmpeg versions
> > compiled with dv1394 support effectively GPL.  It's compiled in by
> > default on platforms that support it.  This looks like a simple
> > oversight, but probably the original author should be asked before this
> > is changed or the code put under CONFIG_GPL.
> Yes this probably won't be an issue but should be resolved.

I'll drop the authors a mail, hopefully they react...

> > libavcodec/i386/idct_mmx.c is marked as GPL but with the exception that
> > it can be used as LGPL in libavcodec.  IMO this is equivalent to
> > releasing it under the LGPL in libavcodec.  The licensing note should be
> > updated.
> Yes, there is not such thing as "GPL for one particular project" or
> "LGPL for one particular project" since both these licenses allow
> unlimited relicensing under themselves. However this sort of language
> from an author is very dangerous IMO because it indicates that they do
> not understand GPL/LGPL at all and might try to attack users who
> exercise their rights under the LGPL at a later time, claiming that
> they did not license under the LGPL when in fact they did.

Precisely my line of thinking, this indicates a confused understanding
of licensing issues, which might lead to problems.

I nevertheless tend to just mark it LGPL and be done with it.

> > libavutil/adler32.c says
> > 
> >  * For conditions of distribution and use, see copyright notice in zlib.h
> > 
> > we don't include zlib.h so the conditions should be pasted there IMO.
> Is adler32.c still used even?

It's unconditionally compiled...

> > libavcodec/truemotion1data.h is taken from GPL code and relicensed under
> > the assumption that data tables are not copyrightable.  Hmmmmm.
> IMO this is totally valid. If you want, use gnu indent to remove all
> information from the file aside from the actual data values.. ;)


I tend to agree that it should be valid.

> > The files listed below have no license header.  I would suggest adding
> > the proper/official (L)GPL license header to them to make things crystal
> > clear.  Some are very short header files, but we have 5 line headers
> > that do come with an LGPL header.  Some are data tables, but we do have
> > data tables that come with an LGPL header.
> Data tables with any copyright attached just make you look like a fool
> IMO. See ESR's comments in terminfo.src for a good laugh. :)


We should be consistent.  IMO either we apply a license to none or
all data tables.

> > Thoughts/comments/flames welcome.
> :)))

What, no comment/flame on the general idea of adding official license
headers everywhere? :)


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