Rename interpretor to interpreter.

[Faustine.git] / interpreter / lib / src / libsndfile-1.0.25 / tests / dft_cmp.c

diff --git a/interpreter/lib/src/libsndfile-1.0.25/tests/dft_cmp.c b/interpreter/lib/src/libsndfile-1.0.25/tests/dft_cmp.c
new file mode 100644 (file)
index 0000000..c902769
--- /dev/null
+++ b/interpreter/lib/src/libsndfile-1.0.25/tests/dft_cmp.c
@@ -0,0 +1,149 @@
+/*
+** Copyright (C) 2002-2011 Erik de Castro Lopo <erikd@mega-nerd.com>
+**
+** This program 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; either version 2 of the License, or
+** (at your option) any later version.
+**
+** This program 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 this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+*/
+
+#include       <stdio.h>
+#include       <stdlib.h>
+#include       <math.h>
+
+#include       "dft_cmp.h"
+#include       "utils.h"
+
+#ifndef                M_PI
+#define                M_PI            3.14159265358979323846264338
+#endif
+
+#define                DFT_SPEC_LENGTH         (DFT_DATA_LENGTH / 2)
+
+static void    dft_magnitude (const double *data, double *spectrum) ;
+static double calc_max_spectral_difference (const double *spec1, const double *spec2) ;
+
+/*--------------------------------------------------------------------------------
+**     Public functions.
+*/
+
+double
+dft_cmp_float (int linenum, const float *in_data, const float *test_data, int len, double target_snr, int allow_exit)
+{      static double orig [DFT_DATA_LENGTH] ;
+       static double test [DFT_DATA_LENGTH] ;
+       unsigned        k ;
+
+       if (len != DFT_DATA_LENGTH)
+       {       printf ("Error (line %d) : dft_cmp_float : Bad input array length.\n", linenum) ;
+               return 1 ;
+               } ;
+
+       for (k = 0 ; k < ARRAY_LEN (orig) ; k++)
+       {       test [k] = test_data [k] ;
+               orig [k] = in_data [k] ;
+               } ;
+
+       return dft_cmp_double (linenum, orig, test, len, target_snr, allow_exit) ;
+} /* dft_cmp_float */
+
+double
+dft_cmp_double (int linenum, const double *orig, const double *test, int len, double target_snr, int allow_exit)
+{      static double orig_spec [DFT_SPEC_LENGTH] ;
+       static double test_spec [DFT_SPEC_LENGTH] ;
+       double          snr ;
+
+       if (! orig || ! test)
+       {       printf ("Error (line %d) : dft_cmp_double : Bad input arrays.\n", linenum) ;
+               return 1 ;
+               } ;
+
+       if (len != DFT_DATA_LENGTH)
+       {       printf ("Error (line %d) : dft_cmp_double : Bad input array length.\n", linenum) ;
+               return 1 ;
+               } ;
+
+       dft_magnitude (orig, orig_spec) ;
+       dft_magnitude (test, test_spec) ;
+
+       snr = calc_max_spectral_difference (orig_spec, test_spec) ;
+
+       if (snr > target_snr)
+       {       printf ("\n\nLine %d: Actual SNR (% 4.1f) > target SNR (% 4.1f).\n\n", linenum, snr, target_snr) ;
+               oct_save_double (orig, test, len) ;
+               if (allow_exit)
+                       exit (1) ;
+               } ;
+
+       if (snr < -500.0)
+               snr = -500.0 ;
+
+       return snr ;
+} /* dft_cmp_double */
+
+/*--------------------------------------------------------------------------------
+**     Quick dirty calculation of magnitude spectrum for real valued data using
+**     Discrete Fourier Transform. Since the data is real, the DFT is only
+**     calculated for positive frequencies.
+*/
+
+static void
+dft_magnitude (const double *data, double *spectrum)
+{      static double cos_angle [DFT_DATA_LENGTH] = { 0.0 } ;
+       static double sin_angle [DFT_DATA_LENGTH] ;
+
+       double  real_part, imag_part ;
+       int             k, n ;
+
+       /* If sine and cosine tables haven't been initialised, do so. */
+       if (cos_angle [0] == 0.0)
+               for (n = 0 ; n < DFT_DATA_LENGTH ; n++)
+               {       cos_angle [n] = cos (2.0 * M_PI * n / DFT_DATA_LENGTH) ;
+                       sin_angle [n] = -1.0 * sin (2.0 * M_PI * n / DFT_DATA_LENGTH) ;
+                       } ;
+
+       /* DFT proper. Since the data is real, only generate a half spectrum. */
+       for (k = 1 ; k < DFT_SPEC_LENGTH ; k++)
+       {       real_part = 0.0 ;
+               imag_part = 0.0 ;
+
+               for (n = 0 ; n < DFT_DATA_LENGTH ; n++)
+               {       real_part += data [n] * cos_angle [(k * n) % DFT_DATA_LENGTH] ;
+                       imag_part += data [n] * sin_angle [(k * n) % DFT_DATA_LENGTH] ;
+                       } ;
+
+               spectrum [k] = sqrt (real_part * real_part + imag_part * imag_part) ;
+               } ;
+
+       spectrum [k] = 0.0 ;
+
+       spectrum [0] = spectrum [1] = spectrum [2] = spectrum [3] = spectrum [4] = 0.0 ;
+
+       return ;
+} /* dft_magnitude */
+
+static double
+calc_max_spectral_difference (const double *orig, const double *test)
+{      double orig_max = 0.0, max_diff = 0.0 ;
+       int     k ;
+
+       for (k = 0 ; k < DFT_SPEC_LENGTH ; k++)
+       {       if (orig_max < orig [k])
+                       orig_max = orig [k] ;
+               if (max_diff < fabs (orig [k] - test [k]))
+                       max_diff = fabs (orig [k] - test [k]) ;
+               } ;
+
+       if (max_diff < 1e-25)
+               return -500.0 ;
+
+       return 20.0 * log10 (max_diff / orig_max) ;
+} /* calc_max_spectral_difference */