PortAudio  2.0
paex_wmme_surround.c
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1 
6 /*
7  * $Id: $
8  * Portable Audio I/O Library
9  * Windows MME surround sound output test
10  *
11  * Copyright (c) 2007 Ross Bencina
12  *
13  * Permission is hereby granted, free of charge, to any person obtaining
14  * a copy of this software and associated documentation files
15  * (the "Software"), to deal in the Software without restriction,
16  * including without limitation the rights to use, copy, modify, merge,
17  * publish, distribute, sublicense, and/or sell copies of the Software,
18  * and to permit persons to whom the Software is furnished to do so,
19  * subject to the following conditions:
20  *
21  * The above copyright notice and this permission notice shall be
22  * included in all copies or substantial portions of the Software.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
27  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
28  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
29  * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
30  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
31  */
32 
33 /*
34  * The text above constitutes the entire PortAudio license; however,
35  * the PortAudio community also makes the following non-binding requests:
36  *
37  * Any person wishing to distribute modifications to the Software is
38  * requested to send the modifications to the original developer so that
39  * they can be incorporated into the canonical version. It is also
40  * requested that these non-binding requests be included along with the
41  * license above.
42  */
43 
44 #include <stdio.h>
45 #include <math.h>
46 
47 #include <windows.h> /* required when using pa_win_wmme.h */
48 #include <mmsystem.h> /* required when using pa_win_wmme.h */
49 
50 #include "portaudio.h"
51 #include "pa_win_wmme.h"
52 
53 #define NUM_SECONDS (12)
54 #define SAMPLE_RATE (44100)
55 #define FRAMES_PER_BUFFER (64)
56 
57 #ifndef M_PI
58 #define M_PI (3.14159265)
59 #endif
60 
61 #define TABLE_SIZE (100)
62 
63 #define CHANNEL_COUNT (6)
64 
65 
66 
67 typedef struct
68 {
69  float sine[TABLE_SIZE];
70  int phase;
71  int currentChannel;
72  int cycleCount;
73 }
75 
76 /* This routine will be called by the PortAudio engine when audio is needed.
77 ** It may called at interrupt level on some machines so don't do anything
78 ** that could mess up the system like calling malloc() or free().
79 */
80 static int patestCallback( const void *inputBuffer, void *outputBuffer,
81  unsigned long framesPerBuffer,
82  const PaStreamCallbackTimeInfo* timeInfo,
83  PaStreamCallbackFlags statusFlags,
84  void *userData )
85 {
86  paTestData *data = (paTestData*)userData;
87  float *out = (float*)outputBuffer;
88  unsigned long i,j;
89 
90  (void) timeInfo; /* Prevent unused variable warnings. */
91  (void) statusFlags;
92  (void) inputBuffer;
93 
94  for( i=0; i<framesPerBuffer; i++ )
95  {
96  for( j = 0; j < CHANNEL_COUNT; ++j ){
97  if( j == data->currentChannel && data->cycleCount < 4410 ){
98  *out++ = data->sine[data->phase];
99  data->phase += 1 + j; // play each channel at a different pitch so they can be distinguished
100  if( data->phase >= TABLE_SIZE ){
101  data->phase -= TABLE_SIZE;
102  }
103  }else{
104  *out++ = 0;
105  }
106  }
107 
108  data->cycleCount++;
109  if( data->cycleCount > 44100 ){
110  data->cycleCount = 0;
111 
112  ++data->currentChannel;
113  if( data->currentChannel >= CHANNEL_COUNT )
114  data->currentChannel -= CHANNEL_COUNT;
115  }
116  }
117 
118  return paContinue;
119 }
120 
121 /*******************************************************************/
122 int main(int argc, char* argv[])
123 {
124  PaStreamParameters outputParameters;
125  PaWinMmeStreamInfo wmmeStreamInfo;
126  PaStream *stream;
127  PaError err;
128  paTestData data;
129  int i;
130  int deviceIndex;
131 
132  printf("PortAudio Test: output a sine blip on each channel. SR = %d, BufSize = %d, Chans = %d\n", SAMPLE_RATE, FRAMES_PER_BUFFER, CHANNEL_COUNT);
133 
134  err = Pa_Initialize();
135  if( err != paNoError ) goto error;
136 
138  if( argc == 2 ){
139  sscanf( argv[1], "%d", &deviceIndex );
140  }
141 
142  printf( "using device id %d (%s)\n", deviceIndex, Pa_GetDeviceInfo(deviceIndex)->name );
143 
144  /* initialise sinusoidal wavetable */
145  for( i=0; i<TABLE_SIZE; i++ )
146  {
147  data.sine[i] = (float) sin( ((double)i/(double)TABLE_SIZE) * M_PI * 2. );
148  }
149 
150  data.phase = 0;
151  data.currentChannel = 0;
152  data.cycleCount = 0;
153 
154  outputParameters.device = deviceIndex;
155  outputParameters.channelCount = CHANNEL_COUNT;
156  outputParameters.sampleFormat = paFloat32; /* 32 bit floating point processing */
157  outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
158  outputParameters.hostApiSpecificStreamInfo = NULL;
159 
160  /* it's not strictly necessary to provide a channelMask for surround sound
161  output. But if you want to be sure which channel mask PortAudio will use
162  then you should supply one */
163  wmmeStreamInfo.size = sizeof(PaWinMmeStreamInfo);
164  wmmeStreamInfo.hostApiType = paMME;
165  wmmeStreamInfo.version = 1;
166  wmmeStreamInfo.flags = paWinMmeUseChannelMask;
167  wmmeStreamInfo.channelMask = PAWIN_SPEAKER_5POINT1; /* request 5.1 output format */
168  outputParameters.hostApiSpecificStreamInfo = &wmmeStreamInfo;
169 
170 
171  if( Pa_IsFormatSupported( 0, &outputParameters, SAMPLE_RATE ) == paFormatIsSupported ){
172  printf( "Pa_IsFormatSupported reports device will support %d channels.\n", CHANNEL_COUNT );
173  }else{
174  printf( "Pa_IsFormatSupported reports device will not support %d channels.\n", CHANNEL_COUNT );
175  }
176 
177  err = Pa_OpenStream(
178  &stream,
179  NULL, /* no input */
180  &outputParameters,
181  SAMPLE_RATE,
182  FRAMES_PER_BUFFER,
183  paClipOff, /* we won't output out of range samples so don't bother clipping them */
184  patestCallback,
185  &data );
186  if( err != paNoError ) goto error;
187 
188  err = Pa_StartStream( stream );
189  if( err != paNoError ) goto error;
190 
191  printf("Play for %d seconds.\n", NUM_SECONDS );
192  Pa_Sleep( NUM_SECONDS * 1000 );
193 
194  err = Pa_StopStream( stream );
195  if( err != paNoError ) goto error;
196 
197  err = Pa_CloseStream( stream );
198  if( err != paNoError ) goto error;
199 
200  Pa_Terminate();
201  printf("Test finished.\n");
202 
203  return err;
204 error:
205  Pa_Terminate();
206  fprintf( stderr, "An error occured while using the portaudio stream\n" );
207  fprintf( stderr, "Error number: %d\n", err );
208  fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
209  return err;
210 }
211