1 /* Simple example of using SoX libraries
2 *
3 * Copyright (c) 2007-8 robs@users.sourceforge.net
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
13 * Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 */
19
20 #ifdef NDEBUG /* N.B. assert used with active statements so enable always. */
21 #undef NDEBUG /* Must undef above assert.h or other that might include it. */
22 #endif
23
24 #include "sox.h"
25 #include <stdlib.h>
26 #include <stdio.h>
27 #include <assert.h>
28
29 /*
30 * Reads input file, applies vol & flanger effects, stores in output file.
31 * E.g. example1 monkey.au monkey.aiff
32 */
main(int argc,char * argv[])33 int main(int argc, char * argv[])
34 {
35 static sox_format_t * in, * out; /* input and output files */
36 sox_effects_chain_t * chain;
37 sox_effect_t * e;
38 char * args[10];
39
40 assert(argc == 3);
41
42 /* All libSoX applications must start by initialising the SoX library */
43 assert(sox_init() == SOX_SUCCESS);
44
45 /* Open the input file (with default parameters) */
46 assert((in = sox_open_read(argv[1], NULL, NULL, NULL)));
47
48 /* Open the output file; we must specify the output signal characteristics.
49 * Since we are using only simple effects, they are the same as the input
50 * file characteristics */
51 assert((out = sox_open_write(argv[2], &in->signal, NULL, NULL, NULL, NULL)));
52
53 /* Create an effects chain; some effects need to know about the input
54 * or output file encoding so we provide that information here */
55 chain = sox_create_effects_chain(&in->encoding, &out->encoding);
56
57 /* The first effect in the effect chain must be something that can source
58 * samples; in this case, we use the built-in handler that inputs
59 * data from an audio file */
60 e = sox_create_effect(sox_find_effect("input"));
61 args[0] = (char *)in, assert(sox_effect_options(e, 1, args) == SOX_SUCCESS);
62 /* This becomes the first `effect' in the chain */
63 assert(sox_add_effect(chain, e, &in->signal, &in->signal) == SOX_SUCCESS);
64 free(e);
65
66 /* Create the `vol' effect, and initialise it with the desired parameters: */
67 e = sox_create_effect(sox_find_effect("vol"));
68 args[0] = "3dB", assert(sox_effect_options(e, 1, args) == SOX_SUCCESS);
69 /* Add the effect to the end of the effects processing chain: */
70 assert(sox_add_effect(chain, e, &in->signal, &in->signal) == SOX_SUCCESS);
71 free(e);
72
73 /* Create the `flanger' effect, and initialise it with default parameters: */
74 e = sox_create_effect(sox_find_effect("flanger"));
75 assert(sox_effect_options(e, 0, NULL) == SOX_SUCCESS);
76 /* Add the effect to the end of the effects processing chain: */
77 assert(sox_add_effect(chain, e, &in->signal, &in->signal) == SOX_SUCCESS);
78 free(e);
79
80 /* The last effect in the effect chain must be something that only consumes
81 * samples; in this case, we use the built-in handler that outputs
82 * data to an audio file */
83 e = sox_create_effect(sox_find_effect("output"));
84 args[0] = (char *)out, assert(sox_effect_options(e, 1, args) == SOX_SUCCESS);
85 assert(sox_add_effect(chain, e, &in->signal, &in->signal) == SOX_SUCCESS);
86 free(e);
87
88 /* Flow samples through the effects processing chain until EOF is reached */
89 sox_flow_effects(chain, NULL, NULL);
90
91 /* All done; tidy up: */
92 sox_delete_effects_chain(chain);
93 sox_close(out);
94 sox_close(in);
95 sox_quit();
96 return 0;
97 }
98