[seiscomp, scanloc] Install, add .gitignore

include/seiscomp/math/hilbert.ipp

@@ -0,0 +1,109 @@
+/***************************************************************************
+ * Copyright (C) gempa GmbH                                                *
+ * All rights reserved.                                                    *
+ * Contact: gempa GmbH (seiscomp-dev@gempa.de)                             *
+ *                                                                         *
+ * GNU Affero General Public License Usage                                 *
+ * This file may be used under the terms of the GNU Affero                 *
+ * Public License version 3.0 as published by the Free Software Foundation *
+ * and appearing in the file LICENSE included in the packaging of this     *
+ * file. Please review the following information to ensure the GNU Affero  *
+ * Public License version 3.0 requirements will be met:                    *
+ * https://www.gnu.org/licenses/agpl-3.0.html.                             *
+ *                                                                         *
+ * Other Usage                                                             *
+ * Alternatively, this file may be used in accordance with the terms and   *
+ * conditions contained in a signed written agreement between you and      *
+ * gempa GmbH.                                                             *
+ ***************************************************************************/
+
+
+#include<math.h>
+
+// Disable hilbert transformation for now
+#if 0
+
+#include<fftw3.h>
+
+namespace Seiscomp
+{
+namespace Math
+{
+namespace Filtering
+{
+
+
+// low-level, real in-place hilbert transform
+//
+// The trace length need not be a power of 2
+template<typename TYPE>
+void hilbert_transform(std::vector<TYPE> &trace,
+		       int direction=1)
+{
+	TYPE *f = &trace[0];
+        int ndata=trace.size(),
+	    nfft = next_power_of_2(ndata),
+	    n2 = nfft/2;
+
+        // temporary trace for real FFTW
+	std::vector<double> temp(nfft);
+	double *g = &temp[0];
+        // copy real array and pad with zeros
+        for (int i=0; i<ndata; i++)
+                g[i] = f[i];
+        for (int i=ndata; i<nfft; i++)
+                g[i] = 0.;
+
+        fftw_plan plan_fwd, plan_inv;
+	plan_fwd = fftw_plan_r2r_1d (nfft, g, g, FFTW_R2HC, FFTW_ESTIMATE);
+	plan_inv = fftw_plan_r2r_1d (nfft, g, g, FFTW_HC2R, FFTW_ESTIMATE);
+
+        fftw_execute(plan_fwd); // forward FFT
+
+        // perform actual Hilbert transform in frequency domain
+        if (direction>0)
+	{
+                for (int i=1; i<n2; i++)
+		{
+                        double x  = g[nfft-i];
+                        g[nfft-i] = -g[i];
+                        g[i]      = x;
+                }
+	}
+        else	{
+		for (int i=1; i<n2; i++) {
+                        double x  = g[nfft-i];
+                        g[nfft-i] = g[i];
+                        g[i]      = -x;
+                }
+	}
+
+        fftw_execute(plan_inv); // inverse FFT
+
+        // scale and copy back to real array
+        double q = 1./nfft;
+        for (int i=0; i<ndata; i++)
+                f[i] = q * g[i];
+
+	fftw_destroy_plan(plan_fwd);
+	fftw_destroy_plan(plan_inv);
+}
+
+template<typename TYPE>
+void envelope(std::vector<TYPE> &trace)
+{
+	std::vector<TYPE> copy(trace.begin(), trace.end());
+	hilbert_transform(copy);
+	int nsamp = trace.size();
+	TYPE *f1 = &trace[0], *f2 = &copy[0];
+	for(int i=0; i<nsamp; i++)
+		f1[i] = (TYPE) ::sqrt( f1[i]*f1[i] + f2[i]*f2[i] );
+}
+
+} // namespace Seiscomp::Math::Filter
+
+} // namespace Seiscomp::Math
+
+} // namespace Seiscomp
+
+#endif