1 /** @file paex_sine.c
2 @ingroup examples_src
3 @brief Play a sine wave for several seconds.
4 @author Ross Bencina <rossb@audiomulch.com>
5 @author Phil Burk <philburk@softsynth.com>
6 */
7 /*
8 * $Id: paex_sine.c 1752 2011-09-08 03:21:55Z philburk $
9 *
10 * This program uses the PortAudio Portable Audio Library.
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 #include <stdio.h>
45 #include <math.h>
46 #include "portaudio.h"
47
48 #define NUM_SECONDS (5)
49 #define SAMPLE_RATE (44100)
50 #define FRAMES_PER_BUFFER (64)
51
52 #ifndef M_PI
53 #define M_PI (3.14159265)
54 #endif
55
56 #define TABLE_SIZE (200)
57
58 class Sine
59 {
60 public:
Sine()61 Sine() : stream(0), left_phase(0), right_phase(0)
62 {
63 /* initialise sinusoidal wavetable */
64 for( int i=0; i<TABLE_SIZE; i++ )
65 {
66 sine[i] = (float) sin( ((double)i/(double)TABLE_SIZE) * M_PI * 2. );
67 }
68
69 sprintf( message, "No Message" );
70 }
71
open(PaDeviceIndex index)72 bool open(PaDeviceIndex index)
73 {
74 PaStreamParameters outputParameters;
75
76 outputParameters.device = index;
77 if (outputParameters.device == paNoDevice) {
78 return false;
79 }
80
81 const PaDeviceInfo* pInfo = Pa_GetDeviceInfo(index);
82 if (pInfo != 0)
83 {
84 printf("Output device name: '%s'\r", pInfo->name);
85 }
86
87 outputParameters.channelCount = 2; /* stereo output */
88 outputParameters.sampleFormat = paFloat32; /* 32 bit floating point output */
89 outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
90 outputParameters.hostApiSpecificStreamInfo = NULL;
91
92 PaError err = Pa_OpenStream(
93 &stream,
94 NULL, /* no input */
95 &outputParameters,
96 SAMPLE_RATE,
97 paFramesPerBufferUnspecified,
98 paClipOff, /* we won't output out of range samples so don't bother clipping them */
99 &Sine::paCallback,
100 this /* Using 'this' for userData so we can cast to Sine* in paCallback method */
101 );
102
103 if (err != paNoError)
104 {
105 /* Failed to open stream to device !!! */
106 return false;
107 }
108
109 err = Pa_SetStreamFinishedCallback( stream, &Sine::paStreamFinished );
110
111 if (err != paNoError)
112 {
113 Pa_CloseStream( stream );
114 stream = 0;
115
116 return false;
117 }
118
119 return true;
120 }
121
close()122 bool close()
123 {
124 if (stream == 0)
125 return false;
126
127 PaError err = Pa_CloseStream( stream );
128 stream = 0;
129
130 return (err == paNoError);
131 }
132
133
start()134 bool start()
135 {
136 if (stream == 0)
137 return false;
138
139 PaError err = Pa_StartStream( stream );
140
141 return (err == paNoError);
142 }
143
stop()144 bool stop()
145 {
146 if (stream == 0)
147 return false;
148
149 PaError err = Pa_StopStream( stream );
150
151 return (err == paNoError);
152 }
153
154 private:
155 /* The instance callback, where we have access to every method/variable in object of class Sine */
paCallbackMethod(const void * inputBuffer,void * outputBuffer,unsigned long framesPerBuffer,const PaStreamCallbackTimeInfo * timeInfo,PaStreamCallbackFlags statusFlags)156 int paCallbackMethod(const void *inputBuffer, void *outputBuffer,
157 unsigned long framesPerBuffer,
158 const PaStreamCallbackTimeInfo* timeInfo,
159 PaStreamCallbackFlags statusFlags)
160 {
161 float *out = (float*)outputBuffer;
162 unsigned long i;
163
164 (void) timeInfo; /* Prevent unused variable warnings. */
165 (void) statusFlags;
166 (void) inputBuffer;
167
168 for( i=0; i<framesPerBuffer; i++ )
169 {
170 *out++ = sine[left_phase]; /* left */
171 *out++ = sine[right_phase]; /* right */
172 left_phase += 1;
173 if( left_phase >= TABLE_SIZE ) left_phase -= TABLE_SIZE;
174 right_phase += 3; /* higher pitch so we can distinguish left and right. */
175 if( right_phase >= TABLE_SIZE ) right_phase -= TABLE_SIZE;
176 }
177
178 return paContinue;
179
180 }
181
182 /* This routine will be called by the PortAudio engine when audio is needed.
183 ** It may called at interrupt level on some machines so don't do anything
184 ** that could mess up the system like calling malloc() or free().
185 */
paCallback(const void * inputBuffer,void * outputBuffer,unsigned long framesPerBuffer,const PaStreamCallbackTimeInfo * timeInfo,PaStreamCallbackFlags statusFlags,void * userData)186 static int paCallback( const void *inputBuffer, void *outputBuffer,
187 unsigned long framesPerBuffer,
188 const PaStreamCallbackTimeInfo* timeInfo,
189 PaStreamCallbackFlags statusFlags,
190 void *userData )
191 {
192 /* Here we cast userData to Sine* type so we can call the instance method paCallbackMethod, we can do that since
193 we called Pa_OpenStream with 'this' for userData */
194 return ((Sine*)userData)->paCallbackMethod(inputBuffer, outputBuffer,
195 framesPerBuffer,
196 timeInfo,
197 statusFlags);
198 }
199
200
paStreamFinishedMethod()201 void paStreamFinishedMethod()
202 {
203 printf( "Stream Completed: %s\n", message );
204 }
205
206 /*
207 * This routine is called by portaudio when playback is done.
208 */
paStreamFinished(void * userData)209 static void paStreamFinished(void* userData)
210 {
211 return ((Sine*)userData)->paStreamFinishedMethod();
212 }
213
214 PaStream *stream;
215 float sine[TABLE_SIZE];
216 int left_phase;
217 int right_phase;
218 char message[20];
219 };
220
221 class ScopedPaHandler
222 {
223 public:
ScopedPaHandler()224 ScopedPaHandler()
225 : _result(Pa_Initialize())
226 {
227 }
~ScopedPaHandler()228 ~ScopedPaHandler()
229 {
230 if (_result == paNoError)
231 {
232 Pa_Terminate();
233 }
234 }
235
result() const236 PaError result() const { return _result; }
237
238 private:
239 PaError _result;
240 };
241
242
243 /*******************************************************************/
244 int main(void);
main(void)245 int main(void)
246 {
247 Sine sine;
248
249 printf("PortAudio Test: output sine wave. SR = %d, BufSize = %d\n", SAMPLE_RATE, FRAMES_PER_BUFFER);
250
251 ScopedPaHandler paInit;
252 if( paInit.result() != paNoError ) goto error;
253
254 if (sine.open(Pa_GetDefaultOutputDevice()))
255 {
256 if (sine.start())
257 {
258 printf("Play for %d seconds.\n", NUM_SECONDS );
259 Pa_Sleep( NUM_SECONDS * 1000 );
260
261 sine.stop();
262 }
263
264 sine.close();
265 }
266
267 printf("Test finished.\n");
268 return paNoError;
269
270 error:
271 fprintf( stderr, "An error occured while using the portaudio stream\n" );
272 fprintf( stderr, "Error number: %d\n", paInit.result() );
273 fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( paInit.result() ) );
274 return 1;
275 }
276