1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
|
/******************************************/
/*
playsaw.cpp
by Gary P. Scavone, 2006
This program will output sawtooth waveforms
of different frequencies on each channel.
*/
/******************************************/
#include "RtAudio.h"
#include <iostream>
#include <cstdlib>
/*
typedef signed long MY_TYPE;
#define FORMAT RTAUDIO_SINT24
#define SCALE 2147483647.0
typedef char MY_TYPE;
#define FORMAT RTAUDIO_SINT8
#define SCALE 127.0
*/
typedef signed short MY_TYPE;
#define FORMAT RTAUDIO_SINT16
#define SCALE 32767.0
/*
typedef signed long MY_TYPE;
#define FORMAT RTAUDIO_SINT32
#define SCALE 2147483647.0
typedef float MY_TYPE;
#define FORMAT RTAUDIO_FLOAT32
#define SCALE 1.0
typedef double MY_TYPE;
#define FORMAT RTAUDIO_FLOAT64
#define SCALE 1.0
*/
#define BASE_RATE 0.005
#define TIME 1.0
void usage( void ) {
// Error function in case of incorrect command-line
// argument specifications
std::cout << "\nuseage: playsaw N fs <device> <channelOffset>\n";
std::cout << " where N = number of channels,\n";
std::cout << " fs = the sample rate,\n";
std::cout << " device = optional device to use (default = 0),\n";
std::cout << " and channelOffset = an optional channel offset on the device (default = 0).\n\n";
exit( 0 );
}
unsigned int channels;
RtAudio::StreamOptions options;
//#define USE_INTERLEAVED
#if defined( USE_INTERLEAVED )
// Interleaved buffers
int saw( void *outputBuffer, void *inputBuffer, unsigned int nBufferFrames,
double streamTime, RtAudioStreamStatus status, void *data )
{
unsigned int i, j;
extern unsigned int channels;
MY_TYPE *buffer = (MY_TYPE *) outputBuffer;
double *lastValues = (double *) data;
if ( status )
std::cout << "Stream underflow detected!" << std::endl;
for ( i=0; i<nBufferFrames; i++ ) {
for ( j=0; j<channels; j++ ) {
*buffer++ = (MY_TYPE) (lastValues[j] * SCALE);
lastValues[j] += BASE_RATE * (j+1+(j*0.1));
if ( lastValues[j] >= 1.0 ) lastValues[j] -= 2.0;
}
}
return 0;
}
#else // Use non-interleaved buffers
int saw( void *outputBuffer, void *inputBuffer, unsigned int nBufferFrames,
double streamTime, RtAudioStreamStatus status, void *data )
{
unsigned int i, j;
extern unsigned int channels;
MY_TYPE *buffer = (MY_TYPE *) outputBuffer;
double *lastValues = (double *) data;
if ( status )
std::cout << "Stream underflow detected!" << std::endl;
double increment;
for ( j=0; j<channels; j++ ) {
increment = BASE_RATE * (j+1+(j*0.1));
for ( i=0; i<nBufferFrames; i++ ) {
*buffer++ = (MY_TYPE) (lastValues[j] * SCALE);
lastValues[j] += increment;
if ( lastValues[j] >= 1.0 ) lastValues[j] -= 2.0;
}
}
return 0;
}
#endif
int main( int argc, char *argv[] )
{
unsigned int bufferFrames, fs, device = 0, offset = 0;
// minimal command-line checking
if (argc < 3 || argc > 5 ) usage();
RtAudio dac;
if ( dac.getDeviceCount() < 1 ) {
std::cout << "\nNo audio devices found!\n";
exit( 1 );
}
channels = (unsigned int) atoi( argv[1] );
fs = (unsigned int) atoi( argv[2] );
if ( argc > 3 )
device = (unsigned int) atoi( argv[3] );
if ( argc > 4 )
offset = (unsigned int) atoi( argv[4] );
double *data = (double *) calloc( channels, sizeof( double ) );
// Let RtAudio print messages to stderr.
dac.showWarnings( true );
// Set our stream parameters for output only.
bufferFrames = 256;
RtAudio::StreamParameters oParams;
oParams.deviceId = device;
oParams.nChannels = channels;
oParams.firstChannel = offset;
options.flags |= RTAUDIO_HOG_DEVICE;
options.flags |= RTAUDIO_SCHEDULE_REALTIME;
#if !defined( USE_INTERLEAVED )
options.flags |= RTAUDIO_NONINTERLEAVED;
#endif
try {
dac.openStream( &oParams, NULL, FORMAT, fs, &bufferFrames, &saw, (void *)data, &options );
dac.startStream();
}
catch ( RtError& e ) {
e.printMessage();
goto cleanup;
}
char input;
//std::cout << "Stream latency = " << dac.getStreamLatency() << "\n" << std::endl;
std::cout << "\nPlaying ... press <enter> to quit (buffer size = " << bufferFrames << ").\n";
std::cin.get( input );
try {
// Stop the stream
dac.stopStream();
}
catch ( RtError& e ) {
e.printMessage();
}
cleanup:
if ( dac.isStreamOpen() ) dac.closeStream();
free( data );
return 0;
}
|
