PortAudio
2.0
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00001 00006 /* 00007 * $Id: pa_fuzz.c 1752 2011-09-08 03:21:55Z philburk $ 00008 * 00009 * This program uses the PortAudio Portable Audio Library. 00010 * For more information see: http://www.portaudio.com 00011 * Copyright (c) 1999-2000 Ross Bencina and Phil Burk 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 #include "portaudio.h" 00047 /* 00048 ** Note that many of the older ISA sound cards on PCs do NOT support 00049 ** full duplex audio (simultaneous record and playback). 00050 ** And some only support full duplex at lower sample rates. 00051 */ 00052 #define SAMPLE_RATE (44100) 00053 #define PA_SAMPLE_TYPE paFloat32 00054 #define FRAMES_PER_BUFFER (64) 00055 00056 typedef float SAMPLE; 00057 00058 float CubicAmplifier( float input ); 00059 static int fuzzCallback( const void *inputBuffer, void *outputBuffer, 00060 unsigned long framesPerBuffer, 00061 const PaStreamCallbackTimeInfo* timeInfo, 00062 PaStreamCallbackFlags statusFlags, 00063 void *userData ); 00064 00065 /* Non-linear amplifier with soft distortion curve. */ 00066 float CubicAmplifier( float input ) 00067 { 00068 float output, temp; 00069 if( input < 0.0 ) 00070 { 00071 temp = input + 1.0f; 00072 output = (temp * temp * temp) - 1.0f; 00073 } 00074 else 00075 { 00076 temp = input - 1.0f; 00077 output = (temp * temp * temp) + 1.0f; 00078 } 00079 00080 return output; 00081 } 00082 #define FUZZ(x) CubicAmplifier(CubicAmplifier(CubicAmplifier(CubicAmplifier(x)))) 00083 00084 static int gNumNoInputs = 0; 00085 /* This routine will be called by the PortAudio engine when audio is needed. 00086 ** It may be called at interrupt level on some machines so don't do anything 00087 ** that could mess up the system like calling malloc() or free(). 00088 */ 00089 static int fuzzCallback( const void *inputBuffer, void *outputBuffer, 00090 unsigned long framesPerBuffer, 00091 const PaStreamCallbackTimeInfo* timeInfo, 00092 PaStreamCallbackFlags statusFlags, 00093 void *userData ) 00094 { 00095 SAMPLE *out = (SAMPLE*)outputBuffer; 00096 const SAMPLE *in = (const SAMPLE*)inputBuffer; 00097 unsigned int i; 00098 (void) timeInfo; /* Prevent unused variable warnings. */ 00099 (void) statusFlags; 00100 (void) userData; 00101 00102 if( inputBuffer == NULL ) 00103 { 00104 for( i=0; i<framesPerBuffer; i++ ) 00105 { 00106 *out++ = 0; /* left - silent */ 00107 *out++ = 0; /* right - silent */ 00108 } 00109 gNumNoInputs += 1; 00110 } 00111 else 00112 { 00113 for( i=0; i<framesPerBuffer; i++ ) 00114 { 00115 *out++ = FUZZ(*in++); /* left - distorted */ 00116 *out++ = *in++; /* right - clean */ 00117 } 00118 } 00119 00120 return paContinue; 00121 } 00122 00123 /*******************************************************************/ 00124 int main(void); 00125 int main(void) 00126 { 00127 PaStreamParameters inputParameters, outputParameters; 00128 PaStream *stream; 00129 PaError err; 00130 00131 err = Pa_Initialize(); 00132 if( err != paNoError ) goto error; 00133 00134 inputParameters.device = Pa_GetDefaultInputDevice(); /* default input device */ 00135 if (inputParameters.device == paNoDevice) { 00136 fprintf(stderr,"Error: No default input device.\n"); 00137 goto error; 00138 } 00139 inputParameters.channelCount = 2; /* stereo input */ 00140 inputParameters.sampleFormat = PA_SAMPLE_TYPE; 00141 inputParameters.suggestedLatency = Pa_GetDeviceInfo( inputParameters.device )->defaultLowInputLatency; 00142 inputParameters.hostApiSpecificStreamInfo = NULL; 00143 00144 outputParameters.device = Pa_GetDefaultOutputDevice(); /* default output device */ 00145 if (outputParameters.device == paNoDevice) { 00146 fprintf(stderr,"Error: No default output device.\n"); 00147 goto error; 00148 } 00149 outputParameters.channelCount = 2; /* stereo output */ 00150 outputParameters.sampleFormat = PA_SAMPLE_TYPE; 00151 outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency; 00152 outputParameters.hostApiSpecificStreamInfo = NULL; 00153 00154 err = Pa_OpenStream( 00155 &stream, 00156 &inputParameters, 00157 &outputParameters, 00158 SAMPLE_RATE, 00159 FRAMES_PER_BUFFER, 00160 0, /* paClipOff, */ /* we won't output out of range samples so don't bother clipping them */ 00161 fuzzCallback, 00162 NULL ); 00163 if( err != paNoError ) goto error; 00164 00165 err = Pa_StartStream( stream ); 00166 if( err != paNoError ) goto error; 00167 00168 printf("Hit ENTER to stop program.\n"); 00169 getchar(); 00170 err = Pa_CloseStream( stream ); 00171 if( err != paNoError ) goto error; 00172 00173 printf("Finished. gNumNoInputs = %d\n", gNumNoInputs ); 00174 Pa_Terminate(); 00175 return 0; 00176 00177 error: 00178 Pa_Terminate(); 00179 fprintf( stderr, "An error occured while using the portaudio stream\n" ); 00180 fprintf( stderr, "Error number: %d\n", err ); 00181 fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) ); 00182 return -1; 00183 }