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

Current stable PortAudio source

+/** @file pa_fuzz.c
+	@ingroup examples_src
+    @brief Distort input like a fuzz box.
+	@author Phil Burk  http://www.softsynth.com
+*/
+/*
+ * $Id: pa_fuzz.c 1752 2011-09-08 03:21:55Z philburk $
+ *
+ * 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"
+/*
+** Note that many of the older ISA sound cards on PCs do NOT support
+** full duplex audio (simultaneous record and playback).
+** And some only support full duplex at lower sample rates.
+*/
+#define SAMPLE_RATE         (44100)
+#define PA_SAMPLE_TYPE      paFloat32
+#define FRAMES_PER_BUFFER   (64)
+
+typedef float SAMPLE;
+
+float CubicAmplifier( float input );
+static int fuzzCallback( const void *inputBuffer, void *outputBuffer,
+                         unsigned long framesPerBuffer,
+                         const PaStreamCallbackTimeInfo* timeInfo,
+                         PaStreamCallbackFlags statusFlags,
+                         void *userData );
+
+/* Non-linear amplifier with soft distortion curve. */
+float CubicAmplifier( float input )
+{
+    float output, temp;
+    if( input < 0.0 )
+    {
+        temp = input + 1.0f;
+        output = (temp * temp * temp) - 1.0f;
+    }
+    else
+    {
+        temp = input - 1.0f;
+        output = (temp * temp * temp) + 1.0f;
+    }
+
+    return output;
+}
+#define FUZZ(x) CubicAmplifier(CubicAmplifier(CubicAmplifier(CubicAmplifier(x))))
+
+static int gNumNoInputs = 0;
+/* This routine will be called by the PortAudio engine when audio is needed.
+** It may be 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 fuzzCallback( const void *inputBuffer, void *outputBuffer,
+                         unsigned long framesPerBuffer,
+                         const PaStreamCallbackTimeInfo* timeInfo,
+                         PaStreamCallbackFlags statusFlags,
+                         void *userData )
+{
+    SAMPLE *out = (SAMPLE*)outputBuffer;
+    const SAMPLE *in = (const SAMPLE*)inputBuffer;
+    unsigned int i;
+    (void) timeInfo; /* Prevent unused variable warnings. */
+    (void) statusFlags;
+    (void) userData;
+
+    if( inputBuffer == NULL )
+    {
+        for( i=0; i<framesPerBuffer; i++ )
+        {
+            *out++ = 0;  /* left - silent */
+            *out++ = 0;  /* right - silent */
+        }
+        gNumNoInputs += 1;
+    }
+    else
+    {
+        for( i=0; i<framesPerBuffer; i++ )
+        {
+            *out++ = FUZZ(*in++);  /* left - distorted */
+            *out++ = *in++;          /* right - clean */
+        }
+    }
+    
+    return paContinue;
+}
+
+/*******************************************************************/
+int main(void);
+int main(void)
+{
+    PaStreamParameters inputParameters, outputParameters;
+    PaStream *stream;
+    PaError err;
+
+    err = Pa_Initialize();
+    if( err != paNoError ) goto error;
+
+    inputParameters.device = Pa_GetDefaultInputDevice(); /* default input device */
+    if (inputParameters.device == paNoDevice) {
+      fprintf(stderr,"Error: No default input device.\n");
+      goto error;
+    }
+    inputParameters.channelCount = 2;       /* stereo input */
+    inputParameters.sampleFormat = PA_SAMPLE_TYPE;
+    inputParameters.suggestedLatency = Pa_GetDeviceInfo( inputParameters.device )->defaultLowInputLatency;
+    inputParameters.hostApiSpecificStreamInfo = NULL;
+
+    outputParameters.device = Pa_GetDefaultOutputDevice(); /* default output device */
+    if (outputParameters.device == paNoDevice) {
+      fprintf(stderr,"Error: No default output device.\n");
+      goto error;
+    }
+    outputParameters.channelCount = 2;       /* stereo output */
+    outputParameters.sampleFormat = PA_SAMPLE_TYPE;
+    outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
+    outputParameters.hostApiSpecificStreamInfo = NULL;
+
+    err = Pa_OpenStream(
+              &stream,
+              &inputParameters,
+              &outputParameters,
+              SAMPLE_RATE,
+              FRAMES_PER_BUFFER,
+              0, /* paClipOff, */  /* we won't output out of range samples so don't bother clipping them */
+              fuzzCallback,
+              NULL );
+    if( err != paNoError ) goto error;
+
+    err = Pa_StartStream( stream );
+    if( err != paNoError ) goto error;
+
+    printf("Hit ENTER to stop program.\n");
+    getchar();
+    err = Pa_CloseStream( stream );
+    if( err != paNoError ) goto error;
+
+    printf("Finished. gNumNoInputs = %d\n", gNumNoInputs );
+    Pa_Terminate();
+    return 0;
+
+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 -1;
+}