| /* |
| ** Copyright (C) 2007-2011 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 <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, 0.95, maxabs) ; |
| maxabs = crappy_snare (output, len, len / 4, 0.85, maxabs) ; |
| maxabs = crappy_snare (output, len, 2 * len / 4, 0.85, maxabs) ; |
| crappy_snare (output, len, 3 * len / 4, 0.85, maxabs) ; |
| |
| write_mono_file (filename, format, 44100, output, len) ; |
| |
| free (output) ; |
| } /* generate_file */ |
| |
| static inline float |
| rand_float (void) |
| { return rand () / (0.5 * RAND_MAX) - 1.0 ; |
| } /* rand_float */ |
| |
| static float |
| crappy_snare (float *output, int len, int offset, float gain, float maxabs) |
| { int k ; |
| float env = 0.0 ; |
| |
| for (k = offset ; k < len && env < gain ; k++) |
| { env += 0.03 ; |
| output [k] += env * rand_float () ; |
| maxabs = SF_MAX (maxabs, fabs (output [k])) ; |
| } ; |
| |
| for ( ; k < len && env > 1e-8 ; k++) |
| { env *= 0.995 ; |
| output [k] += env * rand_float () ; |
| maxabs = SF_MAX (maxabs, fabs (output [k])) ; |
| } ; |
| |
| return maxabs ; |
| } /* crappy_snare */ |