PortAudio: paex_mono_asio_channel_select.c Source File

PortAudio 2.0

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paex_mono_asio_channel_select.c
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1
7 /*
8 * $Id: paex_mono_asio_channel_select.c 1756 2011-09-08 06:09:29Z philburk $
9 *
10 * Authors:
11 * Ross Bencina <rossb@audiomulch.com>
12 * Phil Burk <philburk@softsynth.com>
13 *
14 * This program uses the PortAudio Portable Audio Library.
15 * For more information see: http://www.portaudio.com
16 * Copyright (c) 1999-2000 Ross Bencina and Phil Burk
17 *
18 * Permission is hereby granted, free of charge, to any person obtaining
19 * a copy of this software and associated documentation files
20 * (the "Software"), to deal in the Software without restriction,
21 * including without limitation the rights to use, copy, modify, merge,
22 * publish, distribute, sublicense, and/or sell copies of the Software,
23 * and to permit persons to whom the Software is furnished to do so,
24 * subject to the following conditions:
25 *
26 * The above copyright notice and this permission notice shall be
27 * included in all copies or substantial portions of the Software.
28 *
29 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
30 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
31 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
32 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
33 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
34 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
35 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
36 */
37
38 /*
39 * The text above constitutes the entire PortAudio license; however,
40 * the PortAudio community also makes the following non-binding requests:
41 *
42 * Any person wishing to distribute modifications to the Software is
43 * requested to send the modifications to the original developer so that
44 * they can be incorporated into the canonical version. It is also
45 * requested that these non-binding requests be included along with the
46 * license above.
47 */
48
49 #include <stdio.h>
50 #include <math.h>
51 #include "portaudio.h"
52 #include "pa_asio.h"
53
54 #define NUM_SECONDS (10)
55 #define SAMPLE_RATE (44100)
56 #define AMPLITUDE (0.8)
57 #define FRAMES_PER_BUFFER (64)
58 #define OUTPUT_DEVICE Pa_GetDefaultOutputDevice()
59
60 #ifndef M_PI
61 #define M_PI (3.14159265)
62 #endif
63
64 #define TABLE_SIZE (200)
65 typedef struct
66 {
67 float sine[TABLE_SIZE];
68 int phase;
69 }
70 paTestData;
71
72 /* This routine will be called by the PortAudio engine when audio is needed.
73 ** It may called at interrupt level on some machines so don't do anything
74 ** that could mess up the system like calling malloc() or free().
75 */
76 static int patestCallback( const void *inputBuffer, void *outputBuffer,
77 unsigned long framesPerBuffer,
78 const PaStreamCallbackTimeInfo* timeInfo,
79 PaStreamCallbackFlags statusFlags,
80 void *userData )
81 {
82 paTestData *data = (paTestData*)userData;
83 float *out = (float*)outputBuffer;
84 unsigned long i;
85 int finished = 0;
86 /* avoid unused variable warnings */
87 (void) inputBuffer;
88 (void) timeInfo;
89 (void) statusFlags;
90 for( i=0; i<framesPerBuffer; i++ )
91 {
92 *out++ = data->sine[data->phase]; /* left */
93 data->phase += 1;
94 if( data->phase >= TABLE_SIZE ) data->phase -= TABLE_SIZE;
95 }
96 return finished;
97 }
98
99 /*******************************************************************/
100 int main(void);
101 int main(void)
102 {
103 PaStreamParameters outputParameters;
104 PaAsioStreamInfo asioOutputInfo;
105 PaStream *stream;
106 PaError err;
107 paTestData data;
108 int outputChannelSelectors[1];
109 int i;
110 printf("PortAudio Test: output MONO sine wave. SR = %d, BufSize = %d\n", SAMPLE_RATE, FRAMES_PER_BUFFER);
111 /* initialise sinusoidal wavetable */
112 for( i=0; i<TABLE_SIZE; i++ )
113 {
114 data.sine[i] = (float) (AMPLITUDE * sin( ((double)i/(double)TABLE_SIZE) * M_PI * 2. ));
115 }
116 data.phase = 0;
117
118 err = Pa_Initialize();
119 if( err != paNoError ) goto error;
120
121 outputParameters.device = OUTPUT_DEVICE;
122 outputParameters.channelCount = 1; /* MONO output */
123 outputParameters.sampleFormat = paFloat32; /* 32 bit floating point output */
124 outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
125
126 /* Use an ASIO specific structure. WARNING - this is not portable. */
127 asioOutputInfo.size = sizeof(PaAsioStreamInfo);
128 asioOutputInfo.hostApiType = paASIO;
129 asioOutputInfo.version = 1;
130 asioOutputInfo.flags = paAsioUseChannelSelectors;
131 outputChannelSelectors[0] = 1; /* skip channel 0 and use the second (right) ASIO device channel */
132 asioOutputInfo.channelSelectors = outputChannelSelectors;
133 outputParameters.hostApiSpecificStreamInfo = &asioOutputInfo;
134
135 err = Pa_OpenStream(
136 &stream,
137 NULL, /* no input */
138 &outputParameters,
139 SAMPLE_RATE,
140 FRAMES_PER_BUFFER,
141 paClipOff, /* we won't output out of range samples so don't bother clipping them */
142 patestCallback,
143 &data );
144 if( err != paNoError ) goto error;
145
146 err = Pa_StartStream( stream );
147 if( err != paNoError ) goto error;
148
149 printf("Play for %d seconds.\n", NUM_SECONDS ); fflush(stdout);
150 Pa_Sleep( NUM_SECONDS * 1000 );
151
152 err = Pa_StopStream( stream );
153 if( err != paNoError ) goto error;
154
155 err = Pa_CloseStream( stream );
156 if( err != paNoError ) goto error;
157
158 Pa_Terminate();
159 printf("Test finished.\n");
160 return err;
161 error:
162 Pa_Terminate();
163 fprintf( stderr, "An error occured while using the portaudio stream\n" );
164 fprintf( stderr, "Error number: %d\n", err );
165 fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
166 return err;
167 }