calc_envelope.c 3.22 KB
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 Tilman Steinweg committed Oct 01, 2015 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 ``````/*----------------------------------------------------------------------------------------- * Copyright (C) 2013 For the list of authors, see file AUTHORS. * * This file is part of DENISE. * * DENISE is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, version 2.0 of the License only. * * DENISE is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with DENISE. See file COPYING and/or . -----------------------------------------------------------------------------------------*/ /*------------------------------------------------------------------------ * Calculate the envelope of a seismogram via Hilbert transform * last update 27/1/10, L. Rehor * update to FFTW3 01/07/2013 Martin Schaefer * ----------------------------------------------------------------------*/ #include "fd.h" #include void calc_envelope(float ** datatrace, float ** envelope, int ns, int ntr){ /* declaration of variables */ int i,j, nfreq, npad, k; float xr, yr, x, y, dump, a, *h; double npadd; /* declaration of variables for FFTW3*/ fftw_complex *in, *out; fftw_plan p1, p2; /* %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% */ /* calculation of the Hilbert transform */ /* %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% */ /* calculation of the FFT */ npad = (int)(pow(2.0, ceil(log((double)(ns))/log(2.0))+2.0) ); /* ns -> npad for usage in FFT*/ npadd = (double)npad; in = (fftw_complex*) fftw_malloc(sizeof(fftw_complex) * npad); out = (fftw_complex*) fftw_malloc(sizeof(fftw_complex) * npad); /* calculation of the vector h */ h = vector(1,npad); if ((2*(npad/2))==npad) { /* npad is even */ h[1]=1.0; h[npad/2+1]=1.0; for (i=2;i<=(npad/2);i++) { h[i] = 2.0; } } else { /* npad is odd */ h[1]=1.0; for (i=2;i<=((npad+1)/2);i++) { h[i]=2.0;} } for(k=1;k<=ntr;k++){ for (j=0;j