Alex Cohn <alexcohn@...> writes: > On Mon, Dec 5, 2011 at 12:30, kunkka cai <sycsdr@...> wrote: > > Hi, > > I'm developing a free (in price) software which should be able to play mp3 > > files. I know ffmpeg is a great codec, so I want my application to link > > against it. > > Actually I have built some Dlls (avcodec-52.dll, avformat-52.dll, > > avutil-50.dll) without "--enable-gpl" and without "--enable-nofree". And my > > application that linking against those dlls works well. > > Since I don't want my software to be open-source or become under LGPL/GPL. > > That means I don't want to distribute the source code of my application, but > > I can distribute the source code of the ffmpeg dlls I use. > > Yes, you should provide the source code with any build scripts you use.
I am not a native speaker but I wonder if the word "should" (here and below) is the right choice... > > Can I compress them(my application and those dlls) together into a single > > installation file and distribute it on the internet? Or what can I do? > > Yes, you can distribute the binaries of ffmpeg you built, but: > > - The end user should easily find the licensing info for libav > components used in your distribution; The licensing information actually has to be shown to the user. > - The end user should easily find the source code and build > scripts/instructions to rebuild these components if they wish. > > The ultimate solution is to include these sources in your > distribution; after all, it's only around 10 MByte zipped. > > If bundling the sources is not possible or not relevant in your case, > you can keep them separate, but you should provide certain guarantees > that they will be easily and reliably available to anybody who has > your product installed (IMHO this means that you cannot rely on a free > public download site for that). If you don't want to bundle the FFmpeg sources with your product, I strongly suggest you offer them on the same download server and from the same download page where the application is provided (so far, nobody could suggest a better interpretation to "accompany" as required by the license). > - The end user should be able to replace the av libraries in his > installation with the versions built by them. Which is easy if you use FFmpeg shared libraries (dlls). > You carry no obligation that this will work unless they reproduce > precisely your instructions and use the sources that you supplied. > (For example, if they decide to upgrade to latest version of ffmpeg, > or to perform a debug build, whatever). > > This requirement may become tricky or even prohibitive in some > situations (e.g. on iOS platform), but for a typical Windows > application it's enough to write a short instruction for replacing the > ffmpeg dlls (and test it yourself !!). Exactly. (iOS seems to require static linking, some companies offer the object files of their proprietary applications to allow re-linking against different FFmpeg versions.) > Enjoy, > Alex Cohn > > Disclamer: I am not a lawyer, and the advise above is not legally > bounding. In case of miniscule doubt, consult your lawyer who > specializes in open source software. Same here. Carl Eugen _______________________________________________ Libav-user mailing list Libav-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/libav-user