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/** @file patest_ringmix.c
@ingroup test_src
@brief Ring modulate inputs to left output, mix inputs to right output.
*/
/*
* $Id: patest_ringmix.c 1097 2006-08-26 08:27:53Z rossb $
*
* 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 "portaudio.h"
/* This will be called asynchronously by the PortAudio engine. */
static int myCallback( const void *inputBuffer, void *outputBuffer,
unsigned long framesPerBuffer,
const PaStreamCallbackTimeInfo* timeInfo,
PaStreamCallbackFlags statusFlags,
void *userData )
{
const float *in = (const float *) inputBuffer;
float *out = (float *) outputBuffer;
float leftInput, rightInput;
unsigned int i;
/* Read input buffer, process data, and fill output buffer. */
for( i=0; i<framesPerBuffer; i++ )
{
leftInput = *in++; /* Get interleaved samples from input buffer. */
rightInput = *in++;
*out++ = leftInput * rightInput; /* ring modulation */
*out++ = 0.5f * (leftInput + rightInput); /* mix */
}
return 0;
}
/* Open a PortAudioStream to input and output audio data. */
int main(void)
{
PaStream *stream;
Pa_Initialize();
Pa_OpenDefaultStream(
&stream,
2, 2, /* stereo input and output */
paFloat32, 44100.0,
64, /* 64 frames per buffer */
myCallback, NULL );
Pa_StartStream( stream );
Pa_Sleep( 10000 ); /* Sleep for 10 seconds while processing. */
Pa_StopStream( stream );
Pa_CloseStream( stream );
Pa_Terminate();
return 0;
}
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