ffmpeg/COPYING.LGPLv2.1

                  GNU LESSER GENERAL PUBLIC LICENSE
                       Version 2.1, February 1999

 Copyright (C) 1991, 1999 Free Software Foundation, Inc.
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[This is the first released version of the Lesser GPL.  It also counts
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 the version number 2.1.]

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                     END OF TERMS AND CONDITIONS

           How to Apply These Terms to Your New Libraries

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That's all there is to it!