comparison projects/filter_IIR/main.cpp @ 3:6810f166482f

_new IIR filter example

+/*
+ * main.cpp
+ *
+ *  Created on: Oct 24, 2014
+ *      Author: Andrew McPherson and Victor Zappi
+ */
+
+#include <iostream>
+#include <cstdlib>
+#include <libgen.h>
+#include <signal.h>
+#include <string>
+#include <sndfile.h>				// to load audio files
+#include "../../include/RTAudio.h"
+#include "SampleData.h"
+
+using namespace std;
+
+float gCutFreq = 100;
+
+// Load samples from file
+int initFile(string file, SampleData *smp)//float *& smp)
+{
+	SNDFILE *sndfile ;
+	SF_INFO sfinfo ;
+
+	if (!(sndfile = sf_open (file.c_str(), SFM_READ, &sfinfo))) {
+		cout << "Couldn't open file " << file << endl;
+		return 1;
+	}
+
+	int numChan = sfinfo.channels;
+	if(numChan != 1)
+	{
+		cout << "Error: " << file << " is not a mono file" << endl;
+		return 1;
+	}
+
+	smp->sampleLen = sfinfo.frames * numChan;
+	smp->samples = new float[smp->sampleLen];
+	if(smp == NULL){
+		cout << "Could not allocate buffer" << endl;
+		return 1;
+	}
+
+	int subformat = sfinfo.format & SF_FORMAT_SUBMASK;
+	int readcount = sf_read_float(sndfile, smp->samples, smp->sampleLen);
+
+	// Pad with zeros in case we couldn't read whole file
+	for(int k = readcount; k <smp->sampleLen; k++)
+		smp->samples[k] = 0;
+
+	if (subformat == SF_FORMAT_FLOAT || subformat == SF_FORMAT_DOUBLE) {
+		double	scale ;
+		int 	m ;
+
+		sf_command (sndfile, SFC_CALC_SIGNAL_MAX, &scale, sizeof (scale)) ;
+		if (scale < 1e-10)
+			scale = 1.0 ;
+		else
+			scale = 32700.0 / scale ;
+		cout << "File samples scale = " << scale << endl;
+
+		for (m = 0; m < smp->sampleLen; m++)
+			smp->samples[m] *= scale;
+	}
+
+	sf_close(sndfile);
+
+	return 0;
+}
+
+
+// Handle Ctrl-C by requesting that the audio rendering stop
+void interrupt_handler(int var)
+{
+	//rt_task_delete ((RT_TASK *) &gTriggerSamplesTask);
+	gShouldStop = true;
+}
+
+// Print usage information
+void usage(const char * processName)
+{
+	cerr << "Usage: " << processName << " [-h] [-v] [-p period] [-f frequency]" << endl;
+	cerr << "   -h:           Print this menu\n";
+	cerr << "   -v:           Enable verbose messages\n";
+	cerr << "   -p period:    Set the period (hardware buffer) size in sensor frames\n";
+	cerr << "   -m:           Enable the matrix (ADC and DAC) as well as audio\n";
+	cerr << "   -f filename:  Name of the file to load (default is \"sample.wav\")\n";
+	cerr << "   -c freq:      Set the cut off frequency of the filter in Hz\n";
+}
+
+int main(int argc, char *argv[])
+{
+	int verbose = 0;			// Verbose printing level
+	int periodSize = 8;			// Period size in sensor frames
+	int useMatrix = 0;			// Whether to use the matrix or just audio
+	string fileName;			// Name of the sample to load
+
+	SampleData sampleData;		// User define structure to pass data retrieved from file to render function
+	sampleData.samples = 0;
+	sampleData.sampleLen = -1;
+
+	// Parse command-line arguments
+	while (1) {
+		int c;
+		if ((c = getopt(argc, argv, "hp:vms:")) < 0)
+				break;
+		switch (c) {
+		case 'h':
+				usage(basename(argv[0]));
+				exit(0);
+		case 'p':
+				periodSize = atoi(optarg);
+				if(periodSize < 1)
+					periodSize = 1;
+				break;
+		case 'v':
+				verbose = 1;
+				break;
+		case 'm':
+				useMatrix = 1;
+				break;
+		case 'f':
+				fileName = string((char *)optarg);
+				break;
+		case 'c':
+				gCutFreq = atof(optarg);
+				break;
+		case '?':
+		default:
+				usage(basename(argv[0]));
+				exit(1);
+		}
+	}
+
+	if(fileName.empty()){
+		fileName = "filter/longsample.wav";
+	}
+
+	// Set verbose logging information (optional by using value > 0; default is 0)
+	setVerboseLevel(verbose);
+
+	if(verbose) {
+		cout << "Starting with period size " << periodSize << endl;
+		if(useMatrix)
+			cout << "Matrix enabled\n";
+		else
+			cout << "Matrix disabled\n";
+		cout << "Loading file " << fileName << endl;
+	}
+
+	// Load file
+	if(initFile(fileName, &sampleData) != 0)
+	{
+		cout << "Error: unable to load samples " << endl;
+		return -1;
+	}
+
+	if(verbose)
+		cout << "File contains " << sampleData.sampleLen << " samples" << endl;
+
+	// Initialise the PRU audio device
+	if(initAudio(periodSize, useMatrix, &sampleData) != 0) {
+		cout << "Error: unable to initialise audio" << endl;
+		return -1;
+	}
+
+	// Start the audio device running
+	if(startAudio()) {
+		cout << "Error: unable to start real-time audio" << endl;
+		return -1;
+	}
+
+	// Set up interrupt handler to catch Control-C
+	signal(SIGINT, interrupt_handler);
+
+	// Run until told to stop
+	while(!gShouldStop) {
+		usleep(100000);
+	}
+
+	// Stop the audio device
+	stopAudio();
+
+	if(verbose) {
+		cout << "Cleaning up..." << endl;
+	}
+
+	// Clean up any resources allocated for audio
+	cleanupAudio();
+
+	// All done!
+	return 0;
+}