76 lines
2.1 KiB
C
76 lines
2.1 KiB
C
|
/*
|
||
|
|
** Copyright (C) 2007-2012 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 "sfconfig.h"
|
||
|
|
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <string.h>
|
||
|
|
#include <math.h>
|
||
|
|
|
||
|
|
#include <sndfile.h>
|
||
|
|
|
||
|
|
#include "utils.h"
|
||
|
|
#include "generate.h"
|
||
|
|
|
||
|
|
#define SF_MAX(x, y) ((x) > (y) ? (x) : (y))
|
||
|
|
|
||
|
|
static float crappy_snare (float *output, int len, int offset, float gain, float maxabs) ;
|
||
|
|
|
||
|
|
void
|
||
|
|
generate_file (const char * filename, int format, int len)
|
||
|
|
{ float * output ;
|
||
|
|
float maxabs = 0.0 ;
|
||
|
|
|
||
|
|
output = calloc (len, sizeof (float)) ;
|
||
|
|
|
||
|
|
maxabs = crappy_snare (output, len, 0, 0.95f, maxabs) ;
|
||
|
|
maxabs = crappy_snare (output, len, len / 4, 0.85f, maxabs) ;
|
||
|
|
maxabs = crappy_snare (output, len, 2 * len / 4, 0.85f, maxabs) ;
|
||
|
|
crappy_snare (output, len, 3 * len / 4, 0.85f, maxabs) ;
|
||
|
|
|
||
|
|
write_mono_file (filename, format, 44100, output, len) ;
|
||
|
|
|
||
|
|
free (output) ;
|
||
|
|
} /* generate_file */
|
||
|
|
|
||
|
|
static inline float
|
||
|
|
rand_float (void)
|
||
|
|
{ return rand () / (0.5f * (float) RAND_MAX) - 1.0f ;
|
||
|
|
} /* rand_float */
|
||
|
|
|
||
|
|
static float
|
||
|
|
crappy_snare (float *output, int len, int offset, float gain, float maxabs)
|
||
|
|
{ int k ;
|
||
|
|
float env = 0.0f ;
|
||
|
|
|
||
|
|
for (k = offset ; k < len && env < gain ; k++)
|
||
|
|
{ env += 0.03f ;
|
||
|
|
output [k] += env * rand_float () ;
|
||
|
|
maxabs = SF_MAX (maxabs, fabsf (output [k])) ;
|
||
|
|
} ;
|
||
|
|
|
||
|
|
for ( ; k < len && env > 1e-8 ; k++)
|
||
|
|
{ env *= 0.995f ;
|
||
|
|
output [k] += env * rand_float () ;
|
||
|
|
maxabs = SF_MAX (maxabs, fabsf (output [k])) ;
|
||
|
|
} ;
|
||
|
|
|
||
|
|
return maxabs ;
|
||
|
|
} /* crappy_snare */
|