Le 4 Janvier 2006 10:42, Marc Lavallée a écrit :
Le 4 Janvier 2006 05:51, Jamie Bullock a écrit :
Hi,
Whilst we are on the subject of licensing and copyright, I have a related question. If a section of code is ported into another programming language, does the ported code qualify as a new piece of software or a modification of existing software? I ask this, because clearly it has implications for who owns the copyright to the ported code.
For example, I have written an external that uses a Fast Cosine Transform algorithm originally implemented in Fortran, with the code released under the ACM license (http://www.acm.org/pubs/copyright_policy/softwareCRnotice.html). Clearly, if a port into C (as a PD external) is classed as a modification of the existing Fortran code, then I have to license the external under the ACM also. That is, unless the author agrees to relicense the code under the GPL. However, if the PD external is classed as an entirely separate piece of software, just using the same algorithm, could it be relicensed without consent?
Does anyone know the law/etiquette regarding this?
The ACM license is a bit like a the CC attribution/non-commercial license. I'm not sure it can be considered a free software license (it's not listed on gnu.org), but I believe it can be used along with free software. For commercial use, you must contact the author and negociate a licensing agreement. For non-commercial use, you can distribute the source or binaries, even modify and/or integrate the source to your project, but the original code must be indentified as being the property of ACM. So I think you can licence your part as GPL and use the ACM part as instructed by the ACM license.
Jamie, I checked your external (http://www.puredata.org/Members/jb/fct/view) I see that you are already releasing everything with the original ACM license. I think your port of the original FORTRAN routine (http://www.netlib.org/toms/749) does not belong to the ACM.
I'm curious about the Fast Cosine Transform; is it faster than a DCT or a FFT? Why not using the fftw library? -- Marc