MajenkoProjects/AudiobookRecorder
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Cleanup

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This commit is contained in:
Matt Jenkins
2020-02-05 20:03:23 +00:00
parent 450e80ad21
commit 9b23eb56ce
3 changed files with 1 additions and 209 deletions
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1
.gitignore vendored
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@@ -5,3 +5,4 @@ AudiobookRecorder.jar
AudiobookRecorder-linux
AudiobookRecorder-osx.dmg
AudiobookRecorder-win.exe
.*.swp

133
iircoeff.c
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@@ -1,133 +0,0 @@
/*
* Copyright (C) 2002-2006 Felipe Rivera <liebremx at users.sourceforge.net>
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*
* Coefficient stuff
*
* $Id: iir_cfs.c,v 1.2 2006/01/15 00:17:46 liebremx Exp $
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
static const double band_f031[] =
{ 20,25,31.5,40,50,63,80,100,125,160,200,250,315,400,500,630,800,
1000,1250,1600,2000,2500,3150,4000,5000,6300,8000,10000,12500,16000,20000
};
#define GAIN_F0 1.0
#define GAIN_F1 GAIN_F0 / M_SQRT2
#define SAMPLING_FREQ 44100.0
#define TETA(f) (2*M_PI*(double)f/sample_frequency)
#define TWOPOWER(value) (value * value)
#define BETA2(tf0, tf) \
(TWOPOWER(GAIN_F1)*TWOPOWER(cos(tf0)) \
- 2.0 * TWOPOWER(GAIN_F1) * cos(tf) * cos(tf0) \
+ TWOPOWER(GAIN_F1) \
- TWOPOWER(GAIN_F0) * TWOPOWER(sin(tf)))
#define BETA1(tf0, tf) \
(2.0 * TWOPOWER(GAIN_F1) * TWOPOWER(cos(tf)) \
+ TWOPOWER(GAIN_F1) * TWOPOWER(cos(tf0)) \
- 2.0 * TWOPOWER(GAIN_F1) * cos(tf) * cos(tf0) \
- TWOPOWER(GAIN_F1) + TWOPOWER(GAIN_F0) * TWOPOWER(sin(tf)))
#define BETA0(tf0, tf) \
(0.25 * TWOPOWER(GAIN_F1) * TWOPOWER(cos(tf0)) \
- 0.5 * TWOPOWER(GAIN_F1) * cos(tf) * cos(tf0) \
+ 0.25 * TWOPOWER(GAIN_F1) \
- 0.25 * TWOPOWER(GAIN_F0) * TWOPOWER(sin(tf)))
#define GAMMA(beta, tf0) ((0.5 + beta) * cos(tf0))
#define ALPHA(beta) ((0.5 - beta)/2.0)
/*************
* Functions *
*************/
/* Get the band_f031 at both sides of F0. These will be cut at -3dB */
static void find_f1_and_f2(double f0, double octave_percent, double *f1, double *f2)
{
double octave_factor = pow(2.0, octave_percent/2.0);
*f1 = f0/octave_factor;
*f2 = f0*octave_factor;
}
/* Find the quadratic root
* Always return the smallest root */
static int find_root(double a, double b, double c, double *x0) {
double k = c-((b*b)/(4.*a));
double h = -(b/(2.*a));
double x1 = 0.;
if (-(k/a) < 0.)
return -1;
*x0 = h - sqrt(-(k/a));
x1 = h + sqrt(-(k/a));
if (x1 < *x0)
*x0 = x1;
return 0;
}
void calc_coeffs(double sample_frequency)
{
int i, n;
double f1, f2;
double x0;
printf(" public final static IIRCoefficients iir_cf31_%d[] = {\n", (int)sample_frequency);
for (i = 0; i < 31; i++) {
/* Find -3dB frequencies for the center freq */
find_f1_and_f2(band_f031[i], 1.0/3.0, &f1, &f2);
/* Find Beta */
if ( find_root(
BETA2(TETA(band_f031[i]), TETA(f1)),
BETA1(TETA(band_f031[i]), TETA(f1)),
BETA0(TETA(band_f031[i]), TETA(f1)),
&x0) == 0)
{
/* Got a solution, now calculate the rest of the factors */
/* Take the smallest root always (find_root returns the smallest one)
*
* NOTE: The IIR equation is
* y[n] = 2 * (alpha*(x[n]-x[n-2]) + gamma*y[n-1] - beta*y[n-2])
* Now the 2 factor has been distributed in the coefficients
*/
/* Now store the coefficients */
printf(" /* %.1f Hz */\n", band_f031[i]);
printf(" new IIRCoefficients(%.10e, %010e, %.10e),\n",
(double)(2.0 * x0),
(double)(2.0 * ALPHA(x0)),
(double)(2.0 * GAMMA(x0, TETA(band_f031[i])))
);
} else {
printf(" **** Where are the roots?\n");
}
}// for i
printf(" };\n");
}
int main(int argc, char **argv) {
if (argc != 2) {
printf("Usage: iircoeff <sample frequency>\n");
return -1;
}
double f = strtod(argv[1], NULL);
calc_coeffs(f);
}

76
iircoeff.pl
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@@ -1,76 +0,0 @@
#!/usr/bin/perl
use Math::Trig;
my $fs = 48000;
my $q = 1.414;
printCo(20, $fs, $q);
printCo(25, $fs, $q);
printCo(31.5, $fs, $q);
printCo(40, $fs, $q);
printCo(50, $fs, $q);
printCo(63, $fs, $q);
printCo(80, $fs, $q);
printCo(100, $fs, $q);
printCo(125, $fs, $q);
printCo(160, $fs, $q);
printCo(200, $fs, $q);
printCo(250, $fs, $q);
printCo(315, $fs, $q);
printCo(400, $fs, $q);
printCo(500, $fs, $q);
printCo(630, $fs, $q);
printCo(800, $fs, $q);
printCo(1000, $fs, $q);
printCo(1250, $fs, $q);
printCo(1600, $fs, $q);
printCo(2000, $fs, $q);
printCo(2500, $fs, $q);
printCo(3150, $fs, $q);
printCo(4000, $fs, $q);
printCo(5000, $fs, $q);
printCo(6300, $fs, $q);
printCo(8000, $fs, $q);
printCo(10000, $fs, $q);
printCo(12500, $fs, $q);
printCo(16000, $fs, $q);
printCo(20000, $fs, $q);
sub printCo($$$$) {
my $f0 = shift;
my $fs = shift;
my $q = shift;
@coeff = coefficient($f0, $fs, $q);
print "/* $f0 Hz */\n";
printf("new IIRCoefficients(%.10e, %.10e, %.10e),\n" , $coeff[1] * 2, $coeff[0] * 2, $coeff[2] * 2);
}
sub coefficient($$$$) {
my $f0 = shift;
my $fs = shift;
my $q = shift;
my $q2 = $q * $q;
my $f1 = $f0 * (sqrt(1 + (1 / (4 * $q2))) - (1 / (2 * $q)));
my $f2 = $f0 * (sqrt(1 + (1 / (4 * $q2))) + (1 / (2 * $q)));
my $pi = 3.141592653;
my $theta0 = 2 * $pi * ($f0 / $fs);
my $thetaOverTwoQ = $theta0 / (2 * $q);
my $beta = 0.5 * ((1 - tan($thetaOverTwoQ)) / (1 + tan($thetaOverTwoQ)));
my $gamma = (0.5 + $beta) * cos($theta0);
my $alpha = (0.5 - $beta) / 2;
return ($alpha, $beta, $gamma);
}