comparison src/portaudio_20140130/examples/paex_mono_asio_channel_select.c @ 124:e3d5853d5918

Current stable PortAudio source

+/** @file paex_mono_asio_channel_select.c
+	@ingroup examples_src
+	@brief Play a monophonic sine wave on a specific ASIO channel.
+	@author Ross Bencina <[e-mail]>
+	@author Phil Burk <[e-mail]>
+*/
+/*
+ * $Id: paex_mono_asio_channel_select.c 1756 2011-09-08 06:09:29Z philburk $
+ *
+ * Authors:
+ *    Ross Bencina <[e-mail]>
+ *    Phil Burk <[e-mail]>
+ *
+ * This program uses the PortAudio Portable Audio Library.
+ * For more information see: http://www.portaudio.com
+ * Copyright (c) 1999-2000 Ross Bencina and Phil Burk
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+ * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/*
+ * The text above constitutes the entire PortAudio license; however, 
+ * the PortAudio community also makes the following non-binding requests:
+ *
+ * Any person wishing to distribute modifications to the Software is
+ * requested to send the modifications to the original developer so that
+ * they can be incorporated into the canonical version. It is also 
+ * requested that these non-binding requests be included along with the 
+ * license above.
+ */
+
+#include <stdio.h>
+#include <math.h>
+#include "portaudio.h"
+#include "pa_asio.h"
+
+#define NUM_SECONDS   (10)
+#define SAMPLE_RATE   (44100)
+#define AMPLITUDE     (0.8)
+#define FRAMES_PER_BUFFER  (64)
+#define OUTPUT_DEVICE Pa_GetDefaultOutputDevice()
+
+#ifndef M_PI
+#define M_PI  (3.14159265)
+#endif
+
+#define TABLE_SIZE   (200)
+typedef struct
+{
+    float sine[TABLE_SIZE];
+    int phase;
+}
+paTestData;
+
+/* This routine will be called by the PortAudio engine when audio is needed.
+** It may called at interrupt level on some machines so don't do anything
+** that could mess up the system like calling malloc() or free().
+*/
+static int patestCallback( const void *inputBuffer, void *outputBuffer,
+                            unsigned long framesPerBuffer,
+                            const PaStreamCallbackTimeInfo* timeInfo,
+                            PaStreamCallbackFlags statusFlags,
+                            void *userData )
+{
+    paTestData *data = (paTestData*)userData;
+    float *out = (float*)outputBuffer;
+    unsigned long i;
+    int finished = 0;
+    /* avoid unused variable warnings */
+    (void) inputBuffer;
+    (void) timeInfo;
+    (void) statusFlags;
+    for( i=0; i<framesPerBuffer; i++ )
+    {
+        *out++ = data->sine[data->phase];  /* left */
+        data->phase += 1;
+        if( data->phase >= TABLE_SIZE ) data->phase -= TABLE_SIZE;
+    }
+    return finished;
+}
+
+/*******************************************************************/
+int main(void);
+int main(void)
+{
+    PaStreamParameters outputParameters;
+    PaAsioStreamInfo asioOutputInfo;
+    PaStream *stream;
+    PaError err;
+    paTestData data;
+    int outputChannelSelectors[1];
+    int i;
+    printf("PortAudio Test: output MONO sine wave. SR = %d, BufSize = %d\n", SAMPLE_RATE, FRAMES_PER_BUFFER);
+    /* initialise sinusoidal wavetable */
+    for( i=0; i<TABLE_SIZE; i++ )
+    {
+        data.sine[i] = (float) (AMPLITUDE * sin( ((double)i/(double)TABLE_SIZE) * M_PI * 2. ));
+    }
+    data.phase = 0;
+    
+    err = Pa_Initialize();
+    if( err != paNoError ) goto error;
+
+    outputParameters.device = OUTPUT_DEVICE;
+    outputParameters.channelCount = 1;       /* MONO output */
+    outputParameters.sampleFormat = paFloat32; /* 32 bit floating point output */
+    outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
+
+	/* Use an ASIO specific structure. WARNING - this is not portable. */
+    asioOutputInfo.size = sizeof(PaAsioStreamInfo);
+    asioOutputInfo.hostApiType = paASIO;
+    asioOutputInfo.version = 1;
+    asioOutputInfo.flags = paAsioUseChannelSelectors;
+    outputChannelSelectors[0] = 1; /* skip channel 0 and use the second (right) ASIO device channel */
+    asioOutputInfo.channelSelectors = outputChannelSelectors;
+    outputParameters.hostApiSpecificStreamInfo = &asioOutputInfo;
+
+    err = Pa_OpenStream(
+              &stream,
+              NULL, /* no input */
+              &outputParameters,
+              SAMPLE_RATE,
+              FRAMES_PER_BUFFER,
+              paClipOff,      /* we won't output out of range samples so don't bother clipping them */
+              patestCallback,
+              &data );
+    if( err != paNoError ) goto error;
+
+    err = Pa_StartStream( stream );
+    if( err != paNoError ) goto error;
+    
+    printf("Play for %d seconds.\n", NUM_SECONDS ); fflush(stdout);
+    Pa_Sleep( NUM_SECONDS * 1000 );
+
+    err = Pa_StopStream( stream );
+    if( err != paNoError ) goto error;
+    
+    err = Pa_CloseStream( stream );
+    if( err != paNoError ) goto error;
+    
+    Pa_Terminate();
+    printf("Test finished.\n");
+    return err;
+error:
+    Pa_Terminate();
+    fprintf( stderr, "An error occured while using the portaudio stream\n" );
+    fprintf( stderr, "Error number: %d\n", err );
+    fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
+    return err;
+}