PortAudio  2.0
paex_wmme_surround.c
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00001 
00006 /*
00007  * $Id: $
00008  * Portable Audio I/O Library
00009  * Windows MME surround sound output test
00010  *
00011  * Copyright (c) 2007 Ross Bencina
00012  *
00013  * Permission is hereby granted, free of charge, to any person obtaining
00014  * a copy of this software and associated documentation files
00015  * (the "Software"), to deal in the Software without restriction,
00016  * including without limitation the rights to use, copy, modify, merge,
00017  * publish, distribute, sublicense, and/or sell copies of the Software,
00018  * and to permit persons to whom the Software is furnished to do so,
00019  * subject to the following conditions:
00020  *
00021  * The above copyright notice and this permission notice shall be
00022  * included in all copies or substantial portions of the Software.
00023  *
00024  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
00025  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
00026  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
00027  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
00028  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
00029  * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
00030  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00031  */
00032 
00033 /*
00034  * The text above constitutes the entire PortAudio license; however, 
00035  * the PortAudio community also makes the following non-binding requests:
00036  *
00037  * Any person wishing to distribute modifications to the Software is
00038  * requested to send the modifications to the original developer so that
00039  * they can be incorporated into the canonical version. It is also 
00040  * requested that these non-binding requests be included along with the 
00041  * license above.
00042  */
00043 
00044 #include <stdio.h>
00045 #include <math.h>
00046 
00047 #include <windows.h>    /* required when using pa_win_wmme.h */
00048 #include <mmsystem.h>   /* required when using pa_win_wmme.h */
00049 
00050 #include "portaudio.h"
00051 #include "pa_win_wmme.h"
00052 
00053 #define NUM_SECONDS         (12)
00054 #define SAMPLE_RATE         (44100)
00055 #define FRAMES_PER_BUFFER   (64)
00056 
00057 #ifndef M_PI
00058 #define M_PI  (3.14159265)
00059 #endif
00060 
00061 #define TABLE_SIZE          (100)
00062 
00063 #define CHANNEL_COUNT       (6)
00064 
00065 
00066 
00067 typedef struct
00068 {
00069     float sine[TABLE_SIZE];
00070         int phase;
00071         int currentChannel;
00072         int cycleCount;
00073 }
00074 paTestData;
00075 
00076 /* This routine will be called by the PortAudio engine when audio is needed.
00077 ** It may called at interrupt level on some machines so don't do anything
00078 ** that could mess up the system like calling malloc() or free().
00079 */
00080 static int patestCallback( const void *inputBuffer, void *outputBuffer,
00081                             unsigned long framesPerBuffer,
00082                             const PaStreamCallbackTimeInfo* timeInfo,
00083                             PaStreamCallbackFlags statusFlags,
00084                             void *userData )
00085 {
00086     paTestData *data = (paTestData*)userData;
00087     float *out = (float*)outputBuffer;
00088     unsigned long i,j;
00089 
00090     (void) timeInfo; /* Prevent unused variable warnings. */
00091     (void) statusFlags;
00092     (void) inputBuffer;
00093     
00094     for( i=0; i<framesPerBuffer; i++ )
00095     {
00096                 for( j = 0; j < CHANNEL_COUNT; ++j ){
00097                         if( j == data->currentChannel && data->cycleCount < 4410 ){
00098                                 *out++ = data->sine[data->phase];
00099                                 data->phase += 1 + j;   // play each channel at a different pitch so they can be distinguished
00100                                 if( data->phase >= TABLE_SIZE ){
00101                                         data->phase -= TABLE_SIZE;
00102                                 }
00103                         }else{
00104                                 *out++ = 0;
00105                         }
00106                 }
00107     
00108                 data->cycleCount++;
00109                 if( data->cycleCount > 44100 ){
00110                         data->cycleCount = 0;
00111 
00112                         ++data->currentChannel;
00113                         if( data->currentChannel >= CHANNEL_COUNT )
00114                                 data->currentChannel -= CHANNEL_COUNT;
00115                 }
00116         }
00117     
00118     return paContinue;
00119 }
00120 
00121 /*******************************************************************/
00122 int main(int argc, char* argv[])
00123 {
00124     PaStreamParameters outputParameters;
00125     PaWinMmeStreamInfo wmmeStreamInfo;
00126     PaStream *stream;
00127     PaError err;
00128     paTestData data;
00129     int i;
00130     int deviceIndex;
00131 
00132     printf("PortAudio Test: output a sine blip on each channel. SR = %d, BufSize = %d, Chans = %d\n", SAMPLE_RATE, FRAMES_PER_BUFFER, CHANNEL_COUNT);
00133 
00134     err = Pa_Initialize();
00135     if( err != paNoError ) goto error;
00136 
00137         deviceIndex = Pa_GetHostApiInfo( Pa_HostApiTypeIdToHostApiIndex( paMME ) )->defaultOutputDevice;
00138         if( argc == 2 ){
00139                 sscanf( argv[1], "%d", &deviceIndex );
00140         }
00141 
00142         printf( "using device id %d (%s)\n", deviceIndex, Pa_GetDeviceInfo(deviceIndex)->name );
00143 
00144     /* initialise sinusoidal wavetable */
00145     for( i=0; i<TABLE_SIZE; i++ )
00146     {
00147         data.sine[i] = (float) sin( ((double)i/(double)TABLE_SIZE) * M_PI * 2. );
00148     }
00149 
00150         data.phase = 0;
00151         data.currentChannel = 0;
00152         data.cycleCount = 0;
00153 
00154     outputParameters.device = deviceIndex;
00155     outputParameters.channelCount = CHANNEL_COUNT;
00156     outputParameters.sampleFormat = paFloat32; /* 32 bit floating point processing */
00157     outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
00158     outputParameters.hostApiSpecificStreamInfo = NULL;
00159 
00160     /* it's not strictly necessary to provide a channelMask for surround sound
00161        output. But if you want to be sure which channel mask PortAudio will use
00162        then you should supply one */
00163     wmmeStreamInfo.size = sizeof(PaWinMmeStreamInfo);
00164     wmmeStreamInfo.hostApiType = paMME; 
00165     wmmeStreamInfo.version = 1;
00166     wmmeStreamInfo.flags = paWinMmeUseChannelMask;
00167     wmmeStreamInfo.channelMask = PAWIN_SPEAKER_5POINT1; /* request 5.1 output format */
00168     outputParameters.hostApiSpecificStreamInfo = &wmmeStreamInfo;
00169 
00170 
00171         if( Pa_IsFormatSupported( 0, &outputParameters, SAMPLE_RATE ) == paFormatIsSupported  ){
00172                 printf( "Pa_IsFormatSupported reports device will support %d channels.\n", CHANNEL_COUNT );
00173         }else{
00174                 printf( "Pa_IsFormatSupported reports device will not support %d channels.\n", CHANNEL_COUNT );
00175         }
00176 
00177     err = Pa_OpenStream(
00178               &stream,
00179               NULL, /* no input */
00180               &outputParameters,
00181               SAMPLE_RATE,
00182               FRAMES_PER_BUFFER,
00183               paClipOff,      /* we won't output out of range samples so don't bother clipping them */
00184               patestCallback,
00185               &data );
00186     if( err != paNoError ) goto error;
00187 
00188     err = Pa_StartStream( stream );
00189     if( err != paNoError ) goto error;
00190 
00191     printf("Play for %d seconds.\n", NUM_SECONDS );
00192     Pa_Sleep( NUM_SECONDS * 1000 );
00193 
00194     err = Pa_StopStream( stream );
00195     if( err != paNoError ) goto error;
00196 
00197     err = Pa_CloseStream( stream );
00198     if( err != paNoError ) goto error;
00199 
00200     Pa_Terminate();
00201     printf("Test finished.\n");
00202     
00203     return err;
00204 error:
00205     Pa_Terminate();
00206     fprintf( stderr, "An error occured while using the portaudio stream\n" );
00207     fprintf( stderr, "Error number: %d\n", err );
00208     fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
00209     return err;
00210 }
00211