Wavelet Demo comparing linear and non-linear approximation properties.Implemented using dwt_sym and idwt_sym.

demo/wavedemo_sym2.cpp

@@ -0,0 +1,155 @@
+//============================================================================
+// Name        : wavedemo_sym2.cpp
+// Author      : Rafat Hussain
+// Version     :
+// Copyright   : 
+// Description : Wavelet Demo comparing linear and non-linear approximation properties
+//             : of a given wavelet. Implemented using dwt_sym and idwt_sym.
+//============================================================================
+
+#include <iostream>
+#include <fstream>
+#include "wavelet.h"
+#include <vector>
+#include <string>
+#include <cmath>
+#include <algorithm>
+
+using namespace std;
+
+void findthresh(vector<double> vector1, int N, double& t){
+	sort(vector1.begin(), vector1.end(), greater<double>());
+	t = vector1.at(N-1);
+}
+
+int main() {
+	cout << "********J- LEVEL DISCRETE WAVELET TRANSFORM IMPLEMENTATION*********" << endl; // prints
+	    cout << "This program accepts signal from the user in a file format " << endl;
+	    cout << "and performs Discrete Wavelet Transform with specified   " << endl;
+	    cout << "wavelet. "                                               << endl;
+	    cout << "                                                             " << endl;
+	    cout << " The Following Wavelets are in the Database:                 " << endl;
+	    cout << " haar, db1, db2, db3, db4, db5, db6, db7, db8, db9, db10,  "   << endl;
+	    cout << " db11, db12, db13, db14, db15.                               "  << endl;
+	    cout << " bior1.1, bio1.3, bior1.5, bior2.2, bior2.4,bior2.6,bior2.8, " << endl;
+	    cout << " bior3.1, bior3.3, bior3.5, bior3.7, bior3.9, bior4.4,"        << endl;
+	    cout << " bior5.5, bior6.8."                                            << endl;
+	    cout << " coif1, coif2, coif3, coif4, coif5."                           << endl;
+	    cout << "Please Enter the Wavelet Name at the Prompt( No quotes)     :" << endl;
+
+	    string nm; // nm will store the name of Wavelet Family
+	    cin >> nm;
+	    cout << "Enter the name of signal file at the Prompt eg., signal.txt :" << endl;
+	    char inp[50];
+	    cin >> inp;
+	    vector<double> sig;
+	    ifstream sig_inp(inp);
+        if ( !sig_inp.good()){
+        	cout << "The File doesn't exist"<< endl;
+        	exit(1);
+        }
+	    while (sig_inp) {
+	    	double temp;
+	    	sig_inp >> temp;
+	    	sig.push_back(temp);
+	    }
+	    sig.pop_back();
+	    vector<double> original;
+	    original = sig;
+	    cout << "Please Enter the Number of DWT Stages J             :" << endl;
+
+	    int J;
+	    cin >> J ;
+
+        vector<double> dwt_output, flag;
+        vector<int> length1;
+        int ext = 2;
+
+        // perform J-Level DWT
+	    dwt_sym(sig, J, nm, dwt_output,flag, length1,ext );
+
+	    // Performing Linear Approximation by using only first 100 coefficients
+	    // Coefficients in dwt_output are stored as following
+	    // dwt_output =[ Appx(J-1) Detail(J-1) Detail(J-2) .... Detail(0)]
+
+	     int n_coef = 100; // Number of significant coefficients
+
+	     int n_non_sig= dwt_output.size() - n_coef; // Number of Coefficients that will
+	     // be set to zero
+	     dwt_output.erase(dwt_output.end()- n_non_sig,dwt_output.end());
+	     // Deleting last n_non_sig coefficients and replacing them with zeros
+	     dwt_output.insert(dwt_output.end(),n_non_sig,0);
+
+	     ofstream linearsig("linsig.txt");
+	     for (unsigned int i = 0; i < dwt_output.size(); i++) {
+	    	 linearsig << dwt_output[i] << endl;
+
+	     }
+
+	     // Finding IDWT with approximated coefficients
+
+		    vector<double> output;
+		    idwt_sym(dwt_output, flag,nm,output, length1);
+
+	        unsigned int count = output.size();
+	    	ofstream gnulinappx("gnulinappx.dat");
+	    	for (unsigned int i = 0;i < count; i++) {
+	    		gnulinappx << i << " " << output[i] << endl;
+	    	}
+	    	gnulinappx.close();
+
+	    	// Performing Non Linear Approximation by using only most
+	    	// significant coefficients
+
+	        vector<double> dwt_output2, flag2;
+	        vector<int> length2;
+
+	        // perform J-Level DWT
+		    dwt_sym(sig, J, nm, dwt_output2,flag2,length2, ext );
+
+		    double thresh = 0.0;
+
+		    vector<double> temp_dwtoutput;
+		    for (unsigned int i =0; i < dwt_output2.size();i++){
+		    	double temp = abs(dwt_output2[i]);
+		    	temp_dwtoutput.push_back(temp);
+		    }
+		    /*
+		    for (unsigned int i =0; i < temp_dwtoutput.size(); i++){
+		    	cout << temp_dwtoutput[i] << endl;
+		    }
+		    */
+
+		    findthresh(temp_dwtoutput,n_coef, thresh);
+
+		    for (unsigned int i = 0; i < dwt_output2.size();i++){
+		    	double temp = abs(dwt_output2[i]);
+		    	if (temp < thresh){
+		    		dwt_output2.at(i) = 0.0;
+
+		    	}
+		    }
+		    /*
+		    for (unsigned int i =0; i < dwt_output2.size(); i++){
+		    	cout << dwt_output2[i] << endl;
+		    }
+		    */
+
+
+		     // Finding IDWT with approximated coefficients
+
+			    vector<double> output2;
+			    idwt_sym(dwt_output2, flag2,nm,output2, length2);
+
+		        unsigned int count2 = output2.size();
+		        cout << count2 << endl;
+		    	ofstream gnunlappx("gnunlappx.dat");
+		    	for (unsigned int i = 0;i < count2; i++) {
+		    		gnunlappx << i << " " << output2[i] << endl;
+		    	}
+		    	gnunlappx.close();
+
+
+	return 0;
+}
+