github.com/johnnyeven/libtools@v0.0.0-20191126065708-61829c1adf46/third_party/fft2d/LICENSE (about)

     1  Copyright(C) 1997,2001 Takuya OOURA (email: ooura@kurims.kyoto-u.ac.jp).
     2  You may use, copy, modify this code for any purpose and 
     3  without fee. You may distribute this ORIGINAL package.