Although your comment contains an important hint, it also passes the core of my argumentation:

You compare GCC and LilyPond. And you conclude, that — like in case of the GPL licensed GCC where the copyleft effect does not cover its output (the compiled program), — also in case of the GPL licensed LilyPond the copyleft effect does not cover its output (the picture/pdf). Unfortunately, that’s not my point:

I am not arguing that my LilyPond work (or a snippet) is covered by the GPL because it is ‘executed’ by LilyPond. I argue that my code is covered by the GPL if I use (include or copy) a GPL licensed LilyPond snippet. And if it is covered, then in accordance with the GPL §6 (title: “Conveying Non-Source Forms”) also the compiled version is covered by the GPL. (BTW: even a picture is binary code which still must be interpreted).

Nevertheless, your comment contains the important hint, that the FSF does not want that the output is covered by the strong copyleft effect of its programs.

I would be happy if the statement you quoted would be judicially approved! But as long as we do not have such a legal descision there is a great risk that my scientific and artistical music work can freely be used due to the fact that I used a GPL licensed snippet for creating the music scores — a risk, which I don’t want to take.

But even if I agreed with your position, then we both still have to conclude, that we can only distribute/hand-over our LilyPond code under the terms of the GPL, if our code used a GPL licensed snippet. And even this is a strong side effect.

with best regards Karsten

PDF files are not software, but output from software.

Similarly, MIDI files are not software, but output from software.

gcc is licensed under GPL3. Using gcc to compile your program does not require you to distribute your program under GPL terms, because your work is *NOT* a derivative work. Instead, your work is separate work that is created using the tools provided in gcc.

Can you find a single reference in any of the FSF discussion of the GPL that indicates the output of a GPL program is covered by the GPL?

Here are two questions and answers from the FSF GPL FAQ[1] that indicate the output is only covered by the GPL if the output has a verbatim copy of the program. This is not the case for any LSR snippet of which I am aware.

Is there some way that I can GPL the output people get from use of my program? For example, if my program is used to develop hardware designs, can I require that these designs must be free? (#GPLOutput)
In general this is legally impossible; copyright law does not give you any say in the use of the output people make from their data using your program. If the user uses your program to enter or convert her own data, the copyright on the output belongs to her, not you. More generally, when a program translates its input into some other form, the copyright status of the output inherits that of the input it was generated from.

So the only way you have a say in the use of the output is if substantial parts of the output are copied (more or less) from text in your program. For instance, part of the output of Bison (see above) would be covered by the GNU GPL, if we had not made an exception in this specific case.

You could artificially make a program copy certain text into its output even if there is no technical reason to do so. But if that copied text serves no practical purpose, the user could simply delete that text from the output and use only the rest. Then he would not have to obey the conditions on redistribution of the copied text.

In what cases is the output of a GPL program covered by the GPL too? (#WhatCaseIsOutputGPL)
The output of a program is not, in general, covered by the copyright on the code of the program. So the license of the code of the program does not apply to the output, whether you pipe it into a file, make a screenshot, screencast, or video.

The exception would be when the program displays a full screen of text and/or art that comes from the program. Then the copyright on that text and/or art covers the output. Programs that output audio, such as video games, would also fit into this exception.

If the art/music is under the GPL, then the GPL applies when you copy it no matter how you copy it. However, fair use may still apply.

Keep in mind that some programs, particularly video games, can have artwork/audio that is licensed separately from the underlying GPLed game. In such cases, the license on the artwork/audio would dictate the terms under which video/streaming may occur. See also: Can I use the GPL for something other than software?

I do not think the issue you are concerned about is a problem.

Carl Sorensen

1. https://www.gnu.org/licenses/gpl-faq.html#WhatCaseIsOutputGPL