comparison tests/TestWindow.cpp @ 335:0a632ac70945

FFT and window tests

+
+#include "base/Window.h"
+
+#include <iostream>
+
+#define BOOST_TEST_DYN_LINK
+#define BOOST_TEST_MAIN
+
+#include <boost/test/unit_test.hpp>
+
+BOOST_AUTO_TEST_SUITE(TestWindow)
+
+using std::cout;
+using std::endl;
+
+#define COMPARE_ARRAY(a, b)						\
+    for (int cmp_i = 0; cmp_i < (int)(sizeof(a)/sizeof(a[0])); ++cmp_i) { \
+        BOOST_CHECK_SMALL(a[cmp_i] - b[cmp_i], 1e-4);			\
+    }
+
+void
+testSymmetric(double *d, int n)
+{
+    for (int i = 0; i <= n/2; ++i) {
+	BOOST_CHECK_CLOSE(d[i], d[n-i-1], 1e-10);
+    }
+}
+
+BOOST_AUTO_TEST_CASE(periodic)
+{
+    // We can't actually test whether a function is periodic, given
+    // only one cycle of it! But we can make sure that all but the
+    // first sample is symmetric, which is what a symmetric window
+    // becomes when generated in periodic mode
+    double d[9];
+    for (int n = 8; n <= 9; ++n) {
+	for (int wt = (int)FirstWindow; wt <= (int)LastWindow; ++wt) {
+	    for (int i = 0; i < n; ++i) d[i] = 1.0;
+	    Window<double> w((WindowType)wt, n);
+	    w.cut(d);
+	    testSymmetric(d + 1, n - 1);
+	}
+    }
+}
+
+template <int N>
+void testWindow(WindowType type, const double expected[N])
+{
+    double d[N];
+    for (int i = 0; i < N; ++i) d[i] = 1.0;
+    Window<double> w(type, N);
+    w.cut(d);
+    COMPARE_ARRAY(d, expected);
+}
+
+BOOST_AUTO_TEST_CASE(bartlett)
+{
+    double e1[] = { 1 };
+    testWindow<1>(BartlettWindow, e1);
+
+    double e2[] = { 0, 0 };
+    testWindow<2>(BartlettWindow, e2);
+
+    double e3[] = { 0, 2./3., 2./3. };
+    testWindow<3>(BartlettWindow, e3);
+
+    double e4[] = { 0, 1./2., 1., 1./2. };
+    testWindow<4>(BartlettWindow, e4);
+
+    double e5[] = { 0, 1./2., 1., 1., 1./2. };
+    testWindow<5>(BartlettWindow, e5);
+
+    double e6[] = { 0, 1./3., 2./3., 1., 2./3., 1./3. };
+    testWindow<6>(BartlettWindow, e6);
+}
+    
+BOOST_AUTO_TEST_CASE(hamming)
+{
+    double e1[] = { 1 };
+    testWindow<1>(HammingWindow, e1);
+
+    double e10[] = {
+	0.0800, 0.1679, 0.3979, 0.6821, 0.9121,
+        1.0000, 0.9121, 0.6821, 0.3979, 0.1679
+    };
+    testWindow<10>(HammingWindow, e10);
+}
+    
+BOOST_AUTO_TEST_CASE(hann)
+{
+    double e1[] = { 1 };
+    testWindow<1>(HanningWindow, e1);
+
+    double e10[] = {
+        0, 0.0955, 0.3455, 0.6545, 0.9045,
+        1.0000, 0.9045, 0.6545, 0.3455, 0.0955,
+    };
+    testWindow<10>(HanningWindow, e10);
+}
+    
+BOOST_AUTO_TEST_CASE(blackman)
+{
+    double e1[] = { 1 };
+    testWindow<1>(BlackmanWindow, e1);
+
+    double e10[] = {
+        0, 0.0402, 0.2008, 0.5098, 0.8492,
+        1.0000, 0.8492, 0.5098, 0.2008, 0.0402,
+    };
+    testWindow<10>(BlackmanWindow, e10);
+}
+    
+BOOST_AUTO_TEST_SUITE_END()
+