patest_ringmix.c (3317B)
1 /** @file patest_ringmix.c 2 @ingroup test_src 3 @brief Ring modulate inputs to left output, mix inputs to right output. 4 */ 5 /* 6 * $Id$ 7 * 8 * This program uses the PortAudio Portable Audio Library. 9 * For more information see: http://www.portaudio.com 10 * Copyright (c) 1999-2000 Ross Bencina and Phil Burk 11 * 12 * Permission is hereby granted, free of charge, to any person obtaining 13 * a copy of this software and associated documentation files 14 * (the "Software"), to deal in the Software without restriction, 15 * including without limitation the rights to use, copy, modify, merge, 16 * publish, distribute, sublicense, and/or sell copies of the Software, 17 * and to permit persons to whom the Software is furnished to do so, 18 * subject to the following conditions: 19 * 20 * The above copyright notice and this permission notice shall be 21 * included in all copies or substantial portions of the Software. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 26 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR 27 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF 28 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 29 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 30 */ 31 32 /* 33 * The text above constitutes the entire PortAudio license; however, 34 * the PortAudio community also makes the following non-binding requests: 35 * 36 * Any person wishing to distribute modifications to the Software is 37 * requested to send the modifications to the original developer so that 38 * they can be incorporated into the canonical version. It is also 39 * requested that these non-binding requests be included along with the 40 * license above. 41 */ 42 43 44 #include "stdio.h" 45 #include "portaudio.h" 46 /* This will be called asynchronously by the PortAudio engine. */ 47 static int myCallback( const void *inputBuffer, void *outputBuffer, 48 unsigned long framesPerBuffer, 49 const PaStreamCallbackTimeInfo* timeInfo, 50 PaStreamCallbackFlags statusFlags, 51 void *userData ) 52 { 53 const float *in = (const float *) inputBuffer; 54 float *out = (float *) outputBuffer; 55 float leftInput, rightInput; 56 unsigned int i; 57 58 /* Read input buffer, process data, and fill output buffer. */ 59 for( i=0; i<framesPerBuffer; i++ ) 60 { 61 leftInput = *in++; /* Get interleaved samples from input buffer. */ 62 rightInput = *in++; 63 *out++ = leftInput * rightInput; /* ring modulation */ 64 *out++ = 0.5f * (leftInput + rightInput); /* mix */ 65 } 66 return 0; 67 } 68 69 /* Open a PortAudioStream to input and output audio data. */ 70 int main(void) 71 { 72 PaStream *stream; 73 Pa_Initialize(); 74 Pa_OpenDefaultStream( 75 &stream, 76 2, 2, /* stereo input and output */ 77 paFloat32, 44100.0, 78 64, /* 64 frames per buffer */ 79 myCallback, NULL ); 80 Pa_StartStream( stream ); 81 Pa_Sleep( 10000 ); /* Sleep for 10 seconds while processing. */ 82 Pa_StopStream( stream ); 83 Pa_CloseStream( stream ); 84 Pa_Terminate(); 85 return 0; 86 }