What do the LGPL 2.1 and GPL 2 texts and FFmpeg's checklist say about linking and distributing FFmpeg in a media pipeline, and what do they leave unaddressed?
The licence texts shipped with FFmpeg say: under LGPL 2.1 a program that links the library is a 'work that uses the Library' and may be distributed on the distributor's own terms if they allow customer modification and reverse engineering for debugging and provide either relinkable materials/source or use a shared-library mechanism; under GPL v2 a work containing GPL code must be licensed as a whole with corresponding source. Both say running the program is not restricted and its output is covered only if it is itself a work based on the program. FFmpeg's checklist offers one conservative route (no --enable-gpl or --enable-nonfree, dynamic linking). The texts do not discuss subprocess pipelines or hosted services, and the project declines to answer patent questions.
The licence texts shipped with FFmpeg say: under LGPL 2.1 a program that links the library is a 'work that uses the Library' and may be distributed on the distributor's own terms if they allow customer modification and reverse engineering for debugging and provide either relinkable materials/source or use a shared-library mechanism; under GPL v2 a work containing GPL code must be licensed as a whole with corresponding source. Both say running the program is not restricted and its output is covered only if it is itself a work based on the program. FFmpeg's checklist offers one conservative route (no --enable-gpl or --enable-nonfree, dynamic linking). The texts do not discuss subprocess pipelines or hosted services, and the project declines to answer patent questions.
Curator qualifications: Licence texts and legal page read 2026-10-22; no build, link or distribution assessed; not legal advice. Whether a given pipeline architecture (separate process, network service) creates a combined work is not answered by these texts. GPL/nonfree build consequences already reviewed in CA-B559 (C2-B52-H5-09).
Limitations: Licence texts and legal page read 2026-10-22; no build, link or distribution assessed; not legal advice.
Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.
Structured fields
{
"citations": [
{
"url": "https://ffmpeg.org/legal.html",
"note": "FFmpeg COPYING.LGPLv2.1 @946fcce0 lines 140-146, 242-312; FFmpeg COPYING.GPLv2 @946fcce0 lines 72-77, 90-150; ffmpeg.org/legal.html checklist and patent mini-FAQ (readback 2026-10-22); curator grep over both licence texts"
},
{
"url": "https://github.com/FFmpeg/FFmpeg/blob/946fcce07b6dcd0331c8cc609192aeff5e1924f8/LICENSE.md",
"note": "FFmpeg COPYING.LGPLv2.1 @946fcce0 lines 140-146, 242-312; FFmpeg COPYING.GPLv2 @946fcce0 lines 72-77, 90-150; ffmpeg.org/legal.html checklist and patent mini-FAQ (readback 2026-10-22); curator grep over both licence texts"
},
{
"url": "https://github.com/FFmpeg/FFmpeg/blob/946fcce07b6dcd0331c8cc609192aeff5e1924f8/COPYING.GPLv2",
"note": "FFmpeg COPYING.LGPLv2.1 @946fcce0 lines 140-146, 242-312; FFmpeg COPYING.GPLv2 @946fcce0 lines 72-77, 90-150; ffmpeg.org/legal.html checklist and patent mini-FAQ (readback 2026-10-22); curator grep over both licence texts"
},
{
"url": "https://github.com/FFmpeg/FFmpeg/blob/946fcce07b6dcd0331c8cc609192aeff5e1924f8/COPYING.LGPLv2.1",
"note": "FFmpeg COPYING.LGPLv2.1 @946fcce0 lines 140-146, 242-312; FFmpeg COPYING.GPLv2 @946fcce0 lines 72-77, 90-150; ffmpeg.org/legal.html checklist and patent mini-FAQ (readback 2026-10-22); curator grep over both licence texts"
}
]
}Evidence claims
- [sourced_fact] The licence texts shipped with FFmpeg say: under LGPL 2.1 a program that links the library is a 'work that uses the Library' and may be distributed on the distributor's own terms if they allow customer modification and reverse engineering for debugging and provide either relinkable materials/source or use a shared-library mechanism; under GPL v2 a work containing GPL code must be licensed as a whole with corresponding source. Both say running the program is not restricted and its output is covered only if it is itself a work based on the program. FFmpeg's checklist offers one conservative route (no --enable-gpl or --enable-nonfree, dynamic linking). The texts do not discuss subprocess pipelines or hosted services, and the project declines to answer patent questions. · locator: FFmpeg COPYING.LGPLv2.1 @946fcce0 lines 140-146, 242-312; FFmpeg COPYING.GPLv2 @946fcce0 lines 72-77, 90-150; ffmpeg.org/legal.html checklist and patent mini-FAQ (readback 2026-10-22); curator grep over both licence texts source
Rights
| component | license | hosting | redistribution | modification | training | Evidence and notes |
|---|---|---|---|---|---|---|
| documentation | unknown | permitted | permitted | unknown | unknown | Applies to this original summary only, not to the cited sources. |
Linked records
- cites → https://ffmpeg.org/legal.html
- cites → https://github.com/FFmpeg/FFmpeg/blob/946fcce07b6dcd0331c8cc609192aeff5e1924f8/COPYING.GPLv2
- cites → https://github.com/FFmpeg/FFmpeg/blob/946fcce07b6dcd0331c8cc609192aeff5e1924f8/COPYING.LGPLv2.1
- cites → https://github.com/FFmpeg/FFmpeg/blob/946fcce07b6dcd0331c8cc609192aeff5e1924f8/LICENSE.md