diff constant-q-cpp/src/dsp/Window.h @ 366:5d0a2ebb4d17

Bring dependent libraries in to repo

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/constant-q-cpp/src/dsp/Window.h	Fri Jun 24 14:47:45 2016 +0100
@@ -0,0 +1,174 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+/*
+    Constant-Q library
+    Copyright (c) 2013-2014 Queen Mary, University of London
+
+    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 AUTHOR 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.
+
+    Except as contained in this notice, the names of the Centre for
+    Digital Music; Queen Mary, University of London; and Chris Cannam
+    shall not be used in advertising or otherwise to promote the sale,
+    use or other dealings in this Software without prior written
+    authorization.
+*/
+
+#ifndef WINDOW_H
+#define WINDOW_H
+
+#include <cmath>
+#include <iostream>
+#include <map>
+#include <vector>
+
+#include "pi.h"
+
+enum WindowType {
+    RectangularWindow,
+    BartlettWindow,
+    HammingWindow,
+    HanningWindow,
+    BlackmanWindow,
+    BlackmanHarrisWindow,
+
+    FirstWindow = RectangularWindow,
+    LastWindow = BlackmanHarrisWindow
+};
+
+/**
+ * Various shaped windows for sample frame conditioning, including
+ * cosine windows (Hann etc) and triangular and rectangular windows.
+ */
+template <typename T>
+class Window
+{
+public:
+    /**
+     * Construct a windower of the given type and size. 
+     *
+     * Note that the cosine windows are periodic by design, rather
+     * than symmetrical. (A window of size N is equivalent to a
+     * symmetrical window of size N+1 with the final element missing.)
+     */
+    Window(WindowType type, int size) : m_type(type), m_size(size) { encache(); }
+    Window(const Window &w) : m_type(w.m_type), m_size(w.m_size) { encache(); }
+    Window &operator=(const Window &w) {
+	if (&w == this) return *this;
+	m_type = w.m_type;
+	m_size = w.m_size;
+	encache();
+	return *this;
+    }
+    virtual ~Window() { delete[] m_cache; }
+    
+    void cut(T *src) const { cut(src, src); }
+    void cut(const T *src, T *dst) const {
+	for (int i = 0; i < m_size; ++i) dst[i] = src[i] * m_cache[i];
+    }
+
+    WindowType getType() const { return m_type; }
+    int getSize() const { return m_size; }
+
+    std::vector<T> getWindowData() const {
+        std::vector<T> d;
+        for (int i = 0; i < m_size; ++i) {
+            d.push_back(m_cache[i]);
+        }
+        return d;
+    }
+
+protected:
+    WindowType m_type;
+    int m_size;
+    T *m_cache;
+    
+    void encache();
+};
+
+template <typename T>
+void Window<T>::encache()
+{
+    int n = m_size;
+    T *mult = new T[n];
+    int i;
+    for (i = 0; i < n; ++i) mult[i] = 1.0;
+
+    switch (m_type) {
+		
+    case RectangularWindow:
+        for (i = 0; i < n; ++i) {
+            mult[i] = mult[i] * 0.5;
+	}
+	break;
+	    
+    case BartlettWindow:
+        if (n == 2) {
+            mult[0] = mult[1] = 0; // "matlab compatible"
+        } else if (n == 3) {
+            mult[0] = 0;
+            mult[1] = mult[2] = 2./3.;
+        } else if (n > 3) {
+            for (i = 0; i < n/2; ++i) {
+                mult[i] = mult[i] * (i / T(n/2));
+                mult[i + n - n/2] = mult[i + n - n/2] * (1.0 - (i / T(n/2)));
+            }
+	}
+	break;
+	    
+    case HammingWindow:
+        if (n > 1) {
+            for (i = 0; i < n; ++i) {
+                mult[i] = mult[i] * (0.54 - 0.46 * cos(2 * M_PI * i / n));
+            }
+	}
+	break;
+	    
+    case HanningWindow:
+        if (n > 1) {
+            for (i = 0; i < n; ++i) {
+                mult[i] = mult[i] * (0.50 - 0.50 * cos(2 * M_PI * i / n));
+            }
+	}
+	break;
+	    
+    case BlackmanWindow:
+        if (n > 1) {
+            for (i = 0; i < n; ++i) {
+                mult[i] = mult[i] * (0.42 - 0.50 * cos(2 * M_PI * i / n)
+                                     + 0.08 * cos(4 * M_PI * i / n));
+            }
+	}
+	break;
+	    
+    case BlackmanHarrisWindow:
+        if (n > 1) {
+            for (i = 0; i < n; ++i) {
+                mult[i] = mult[i] * (0.35875
+                                     - 0.48829 * cos(2 * M_PI * i / n)
+                                     + 0.14128 * cos(4 * M_PI * i / n)
+                                     - 0.01168 * cos(6 * M_PI * i / n));
+            }
+	}
+	break;
+    }
+	   
+    m_cache = mult;
+}
+
+#endif