On Mon, 15 Jan 2001, Martin Weber <martweb@xxxxxxx> wrote: > I am no GPL expert, but I think it is compatible to GPL, but it does not > have a plugin interface. > [Lourens Veen <jsr@xxxxxx> wrote:] > > But is the license GPL compatible? And is it as flexible as the current > > plugin system? > > [Martin Weber <martweb@xxxxxxx> wrote:] > > > There is a very very fast (faster than Photoshop) image loader > > > called FreeImage: > > > http://home.wxs.nl/~flvdberg/ > > > With small adoptions it also runs with Linux. I had a quick look at the FreeImage license, and I am not sure that it could be GPL-compatible. The license is available in text format from: http://home.wxs.nl/~flvdberg/freeimage-license.txt and in HTML format from: http://home.wxs.nl/~flvdberg/intro.html#license The spirit of this license is similar to the GPL, except that it has some sections specifically addressing the patents that could protect this code. Some things make me think that it could have problems with the GPL: 1) The sections on patents. It specifically states in sections 2.1.b, 2.2.b and 3.4 that the initial developer (Floris van den Berg) or other contributors may have current or future patents on the algorithms or interfaces used in the program. The rights granted on these patents are granted "solely to the extent that any such patent is reasonably necessary to enable You to Utilize the [code] and not to any greater extent that may be necessary to Utilize further Modifications or combinations." This is probably not compatible with the GPL, which forbids you to include any discriminations against the free usage of the code. 2) Section 3.1 states that "You may not offer or impose any terms on any Source Code version that alters or restricts the applicable version of this License or the recipients' rights hereunder." This basically prevents you from changing the license, and I think that some parts of the GPL could be considered as additional restrictions. 3) In section 3.2, the minimum amount of time during which the source code must be offered to anybody who did not get it together with the binaries is shorter than the one required by the GPL. 4) The indemnification clause in section 3.6 seems suspicious to me, and contrary to the "no warranty" of the GPL. 5) Section 3.7 is similar to the virus-like feature of the GPL: the license must be applied to any larger work containing the covered code. Since both the GPL and the FreeImage license state that all of their requirements must be fulfilled by any package including the covered code, and since these licenses seem to have incompatible requirements, I doubt that we can use any of the FreeImage code. So I think that we have no other choice than to stay away from the FreeImage code. Especially if any part of it is covered by some patents. In that case, we should not even look at the code, in order to be sure that we are not involuntarily including any patented stuff in the Gimp. Unless someone who is more qualified than me in legal matters can certify that the FreeImage license is GPL-compatible, we should not use any part of it. -Raphael
