First post, by Wohlstand

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Since a while ago, the chip emulator code is being used around the world out of DosBox, often in various music players, games, bank editors, libraries, etc. It has a GPLv2+ license which means, any project that uses it (even its library), also should use the GPLv2+ license.

I do have two of my projects that use your OPL3 emulator (https://github.com/Wohlstand/libADLMIDI and https://github.com/Wohlstand/OPL3BankEditor). For the libADLMIDI I keep the long-term plan to switch license into at least LGPL because there are some projects that want to use my libADLMIDI library (such as DXX Rebirth), however, they have a GPL-incompatible license (left by the author of the original code) which makes no way to legally link my library to it. Speaking about chip emulators, I use many different emulators (they are different by performance and accuracy level, and they all have LGPL 2.1 license except for Opal (public domain) and DosBox OPL3 (GPLv2+)), and the DosBox OPL3 is the best one for low-end hardware (it's almost accurate and gives the fastest performance, which I measured with my own benchmark at my OPL3 Bank Editor), and I want to keep using it.

And therefore, I have the request (if possible) to switch the license of the dbopl.cpp and dbopl.h emulator's code into LGPLv2.1+.

Is that ever possible?

Reply 2 of 2, by Dominus

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Heya, best contact Qbix or Harekiet directly. Could be that it got lost in the noise.

Looking at the files, though, it seems you need to get Qbix, Harekiet, WD (c2woody) and ripsaw to agree on a license change as all four contributed code under the GPL2 license (that is what I remember how license changes need to work but I'm certainly not a lawyer 😀).

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