Chris@39: /** @file pa_fuzz.c
Chris@39: 	@ingroup examples_src
Chris@39:     @brief Distort input like a fuzz box.
Chris@39: 	@author Phil Burk  http://www.softsynth.com
Chris@39: */
Chris@39: /*
Chris@39:  * $Id: pa_fuzz.c 1752 2011-09-08 03:21:55Z philburk $
Chris@39:  *
Chris@39:  * This program uses the PortAudio Portable Audio Library.
Chris@39:  * For more information see: http://www.portaudio.com
Chris@39:  * Copyright (c) 1999-2000 Ross Bencina and Phil Burk
Chris@39:  *
Chris@39:  * Permission is hereby granted, free of charge, to any person obtaining
Chris@39:  * a copy of this software and associated documentation files
Chris@39:  * (the "Software"), to deal in the Software without restriction,
Chris@39:  * including without limitation the rights to use, copy, modify, merge,
Chris@39:  * publish, distribute, sublicense, and/or sell copies of the Software,
Chris@39:  * and to permit persons to whom the Software is furnished to do so,
Chris@39:  * subject to the following conditions:
Chris@39:  *
Chris@39:  * The above copyright notice and this permission notice shall be
Chris@39:  * included in all copies or substantial portions of the Software.
Chris@39:  *
Chris@39:  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
Chris@39:  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
Chris@39:  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
Chris@39:  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
Chris@39:  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
Chris@39:  * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
Chris@39:  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Chris@39:  */
Chris@39: 
Chris@39: /*
Chris@39:  * The text above constitutes the entire PortAudio license; however, 
Chris@39:  * the PortAudio community also makes the following non-binding requests:
Chris@39:  *
Chris@39:  * Any person wishing to distribute modifications to the Software is
Chris@39:  * requested to send the modifications to the original developer so that
Chris@39:  * they can be incorporated into the canonical version. It is also 
Chris@39:  * requested that these non-binding requests be included along with the 
Chris@39:  * license above.
Chris@39:  */
Chris@39: 
Chris@39: #include <stdio.h>
Chris@39: #include <math.h>
Chris@39: #include "portaudio.h"
Chris@39: /*
Chris@39: ** Note that many of the older ISA sound cards on PCs do NOT support
Chris@39: ** full duplex audio (simultaneous record and playback).
Chris@39: ** And some only support full duplex at lower sample rates.
Chris@39: */
Chris@39: #define SAMPLE_RATE         (44100)
Chris@39: #define PA_SAMPLE_TYPE      paFloat32
Chris@39: #define FRAMES_PER_BUFFER   (64)
Chris@39: 
Chris@39: typedef float SAMPLE;
Chris@39: 
Chris@39: float CubicAmplifier( float input );
Chris@39: static int fuzzCallback( const void *inputBuffer, void *outputBuffer,
Chris@39:                          unsigned long framesPerBuffer,
Chris@39:                          const PaStreamCallbackTimeInfo* timeInfo,
Chris@39:                          PaStreamCallbackFlags statusFlags,
Chris@39:                          void *userData );
Chris@39: 
Chris@39: /* Non-linear amplifier with soft distortion curve. */
Chris@39: float CubicAmplifier( float input )
Chris@39: {
Chris@39:     float output, temp;
Chris@39:     if( input < 0.0 )
Chris@39:     {
Chris@39:         temp = input + 1.0f;
Chris@39:         output = (temp * temp * temp) - 1.0f;
Chris@39:     }
Chris@39:     else
Chris@39:     {
Chris@39:         temp = input - 1.0f;
Chris@39:         output = (temp * temp * temp) + 1.0f;
Chris@39:     }
Chris@39: 
Chris@39:     return output;
Chris@39: }
Chris@39: #define FUZZ(x) CubicAmplifier(CubicAmplifier(CubicAmplifier(CubicAmplifier(x))))
Chris@39: 
Chris@39: static int gNumNoInputs = 0;
Chris@39: /* This routine will be called by the PortAudio engine when audio is needed.
Chris@39: ** It may be called at interrupt level on some machines so don't do anything
Chris@39: ** that could mess up the system like calling malloc() or free().
Chris@39: */
Chris@39: static int fuzzCallback( const void *inputBuffer, void *outputBuffer,
Chris@39:                          unsigned long framesPerBuffer,
Chris@39:                          const PaStreamCallbackTimeInfo* timeInfo,
Chris@39:                          PaStreamCallbackFlags statusFlags,
Chris@39:                          void *userData )
Chris@39: {
Chris@39:     SAMPLE *out = (SAMPLE*)outputBuffer;
Chris@39:     const SAMPLE *in = (const SAMPLE*)inputBuffer;
Chris@39:     unsigned int i;
Chris@39:     (void) timeInfo; /* Prevent unused variable warnings. */
Chris@39:     (void) statusFlags;
Chris@39:     (void) userData;
Chris@39: 
Chris@39:     if( inputBuffer == NULL )
Chris@39:     {
Chris@39:         for( i=0; i<framesPerBuffer; i++ )
Chris@39:         {
Chris@39:             *out++ = 0;  /* left - silent */
Chris@39:             *out++ = 0;  /* right - silent */
Chris@39:         }
Chris@39:         gNumNoInputs += 1;
Chris@39:     }
Chris@39:     else
Chris@39:     {
Chris@39:         for( i=0; i<framesPerBuffer; i++ )
Chris@39:         {
Chris@39:             *out++ = FUZZ(*in++);  /* left - distorted */
Chris@39:             *out++ = *in++;          /* right - clean */
Chris@39:         }
Chris@39:     }
Chris@39:     
Chris@39:     return paContinue;
Chris@39: }
Chris@39: 
Chris@39: /*******************************************************************/
Chris@39: int main(void);
Chris@39: int main(void)
Chris@39: {
Chris@39:     PaStreamParameters inputParameters, outputParameters;
Chris@39:     PaStream *stream;
Chris@39:     PaError err;
Chris@39: 
Chris@39:     err = Pa_Initialize();
Chris@39:     if( err != paNoError ) goto error;
Chris@39: 
Chris@39:     inputParameters.device = Pa_GetDefaultInputDevice(); /* default input device */
Chris@39:     if (inputParameters.device == paNoDevice) {
Chris@39:       fprintf(stderr,"Error: No default input device.\n");
Chris@39:       goto error;
Chris@39:     }
Chris@39:     inputParameters.channelCount = 2;       /* stereo input */
Chris@39:     inputParameters.sampleFormat = PA_SAMPLE_TYPE;
Chris@39:     inputParameters.suggestedLatency = Pa_GetDeviceInfo( inputParameters.device )->defaultLowInputLatency;
Chris@39:     inputParameters.hostApiSpecificStreamInfo = NULL;
Chris@39: 
Chris@39:     outputParameters.device = Pa_GetDefaultOutputDevice(); /* default output device */
Chris@39:     if (outputParameters.device == paNoDevice) {
Chris@39:       fprintf(stderr,"Error: No default output device.\n");
Chris@39:       goto error;
Chris@39:     }
Chris@39:     outputParameters.channelCount = 2;       /* stereo output */
Chris@39:     outputParameters.sampleFormat = PA_SAMPLE_TYPE;
Chris@39:     outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
Chris@39:     outputParameters.hostApiSpecificStreamInfo = NULL;
Chris@39: 
Chris@39:     err = Pa_OpenStream(
Chris@39:               &stream,
Chris@39:               &inputParameters,
Chris@39:               &outputParameters,
Chris@39:               SAMPLE_RATE,
Chris@39:               FRAMES_PER_BUFFER,
Chris@39:               0, /* paClipOff, */  /* we won't output out of range samples so don't bother clipping them */
Chris@39:               fuzzCallback,
Chris@39:               NULL );
Chris@39:     if( err != paNoError ) goto error;
Chris@39: 
Chris@39:     err = Pa_StartStream( stream );
Chris@39:     if( err != paNoError ) goto error;
Chris@39: 
Chris@39:     printf("Hit ENTER to stop program.\n");
Chris@39:     getchar();
Chris@39:     err = Pa_CloseStream( stream );
Chris@39:     if( err != paNoError ) goto error;
Chris@39: 
Chris@39:     printf("Finished. gNumNoInputs = %d\n", gNumNoInputs );
Chris@39:     Pa_Terminate();
Chris@39:     return 0;
Chris@39: 
Chris@39: error:
Chris@39:     Pa_Terminate();
Chris@39:     fprintf( stderr, "An error occured while using the portaudio stream\n" );
Chris@39:     fprintf( stderr, "Error number: %d\n", err );
Chris@39:     fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
Chris@39:     return -1;
Chris@39: }