1 /*
2 * $Id$
3 * test_w_saw8.c
4 * Generate stereo 8 bit sawtooth waveforms.
5 *
6 * Author: Phil Burk, http://www.softsynth.com
7 *
8 * This program uses PABLIO, the Portable Audio Blocking I/O Library.
9 * PABLIO is built on top of PortAudio, the Portable Audio Library.
10 *
11 * For more information see: http://www.portaudio.com
12 * Copyright (c) 1999-2000 Ross Bencina and Phil Burk
13 *
14 * Permission is hereby granted, free of charge, to any person obtaining
15 * a copy of this software and associated documentation files
16 * (the "Software"), to deal in the Software without restriction,
17 * including without limitation the rights to use, copy, modify, merge,
18 * publish, distribute, sublicense, and/or sell copies of the Software,
19 * and to permit persons to whom the Software is furnished to do so,
20 * subject to the following conditions:
21 *
22 * The above copyright notice and this permission notice shall be
23 * included in all copies or substantial portions of the Software.
24 *
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
28 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
29 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
30 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
31 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
32 */
33
34 /*
35 * The text above constitutes the entire PortAudio license; however,
36 * the PortAudio community also makes the following non-binding requests:
37 *
38 * Any person wishing to distribute modifications to the Software is
39 * requested to send the modifications to the original developer so that
40 * they can be incorporated into the canonical version. It is also
41 * requested that these non-binding requests be included along with the
42 * license above.
43 */
44
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <math.h>
48 #include "pablio.h"
49 #include <string.h>
50
51 #define SAMPLE_RATE (22050)
52 #define NUM_SECONDS (6)
53 #define SAMPLES_PER_FRAME (2)
54
55
56 #define FRAMES_PER_BLOCK (100)
57
58 unsigned char samples[FRAMES_PER_BLOCK][SAMPLES_PER_FRAME];
59 unsigned char phases[SAMPLES_PER_FRAME];
60
61 /*******************************************************************/
62 int main(void);
main(void)63 int main(void)
64 {
65 int i,j;
66 PaError err;
67 PABLIO_Stream *aOutStream;
68
69 printf("Generate unsigned 8 bit sawtooth waves using PABLIO.\n");
70 fflush(stdout);
71
72 /* Open simplified blocking I/O layer on top of PortAudio. */
73 err = OpenAudioStream( &aOutStream, SAMPLE_RATE, paUInt8,
74 (PABLIO_WRITE | PABLIO_STEREO) );
75 if( err != paNoError ) goto error;
76
77 /* Initialize oscillator phases to "ground" level for paUInt8. */
78 phases[0] = 128;
79 phases[1] = 128;
80
81 for( i=0; i<(NUM_SECONDS * SAMPLE_RATE); i += FRAMES_PER_BLOCK )
82 {
83 /* Generate sawtooth waveforms in a block for efficiency. */
84 for( j=0; j<FRAMES_PER_BLOCK; j++ )
85 {
86 /* Generate a sawtooth wave by incrementing a variable. */
87 phases[0] += 1;
88 /* We don't have to do anything special to wrap when using paUint8 because
89 * 8 bit arithmetic automatically wraps. */
90 samples[j][0] = phases[0];
91
92 /* On the second channel, generate a higher sawtooth wave. */
93 phases[1] += 3;
94 samples[j][1] = phases[1];
95 }
96
97 /* Write samples to output. */
98 WriteAudioStream( aOutStream, samples, FRAMES_PER_BLOCK );
99 }
100
101 CloseAudioStream( aOutStream );
102
103 printf("Sawtooth sound test complete.\n" );
104 fflush(stdout);
105 return 0;
106
107 error:
108 fprintf( stderr, "An error occured while using PABLIO\n" );
109 fprintf( stderr, "Error number: %d\n", err );
110 fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
111 return -1;
112 }
113