diff src/vamp-hostsdk/Window.h @ 317:5cb298435765

Add support for changing window shape in PluginInputDomainAdapter

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/vamp-hostsdk/Window.h	Tue Jun 21 15:40:50 2011 +0100
@@ -0,0 +1,167 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+/*
+    Vamp
+
+    An API for audio analysis and feature extraction plugins.
+
+    Centre for Digital Music, Queen Mary, University of London.
+    Copyright 2006-2011 Chris Cannam and QMUL.
+
+    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 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 <vamp-hostsdk/hostguard.h>
+
+#include <cmath>
+#include <cstdlib>
+
+_VAMP_SDK_HOSTSPACE_BEGIN(Window.h)
+
+template <typename T>
+class Window
+{
+public:
+    enum WindowType {
+        RectangularWindow,
+        BartlettWindow,
+        HammingWindow,
+        HanningWindow,
+        BlackmanWindow,
+        NuttallWindow,
+        BlackmanHarrisWindow
+    };
+
+    /**
+     * Construct a windower of the given type.
+     */
+    Window(WindowType type, size_t 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(T *src, T *dst) const {
+	for (size_t i = 0; i < m_size; ++i) dst[i] = src[i] * m_cache[i];
+    }
+    template <typename T0>
+    void cut(T0 *src, T *dst) const {
+	for (size_t i = 0; i < m_size; ++i) dst[i] = src[i] * m_cache[i];
+    }
+
+    T getArea() { return m_area; }
+    T getValue(size_t i) { return m_cache[i]; }
+
+    WindowType getType() const { return m_type; }
+    size_t getSize() const { return m_size; }
+
+protected:
+    WindowType m_type;
+    size_t m_size;
+    T *m_cache;
+    T m_area;
+    
+    void encache();
+    void cosinewin(T *, T, T, T, T);
+};
+
+template <typename T>
+void Window<T>::encache()
+{
+    int n = int(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] *= 0.5;
+	}
+	break;
+	    
+    case BartlettWindow:
+	for (i = 0; i < n/2; ++i) {
+	    mult[i] *= (i / T(n/2));
+	    mult[i + n/2] *= (1.0 - (i / T(n/2)));
+	}
+	break;
+	    
+    case HammingWindow:
+        cosinewin(mult, 0.54, 0.46, 0.0, 0.0);
+	break;
+	    
+    case HanningWindow:
+        cosinewin(mult, 0.50, 0.50, 0.0, 0.0);
+	break;
+	    
+    case BlackmanWindow:
+        cosinewin(mult, 0.42, 0.50, 0.08, 0.0);
+	break;
+
+    case NuttallWindow:
+        cosinewin(mult, 0.3635819, 0.4891775, 0.1365995, 0.0106411);
+	break;
+
+    case BlackmanHarrisWindow:
+        cosinewin(mult, 0.35875, 0.48829, 0.14128, 0.01168);
+        break;
+    }
+	
+    m_cache = mult;
+
+    m_area = 0;
+    for (int i = 0; i < n; ++i) {
+        m_area += m_cache[i];
+    }
+    m_area /= n;
+}
+
+template <typename T>
+void Window<T>::cosinewin(T *mult, T a0, T a1, T a2, T a3)
+{
+    int n = int(m_size);
+    for (int i = 0; i < n; ++i) {
+        mult[i] *= (a0
+                    - a1 * cos((2 * M_PI * i) / n)
+                    + a2 * cos((4 * M_PI * i) / n)
+                    - a3 * cos((6 * M_PI * i) / n));
+    }
+}
+
+_VAMP_SDK_HOSTSPACE_END(Window.h)
+
+#endif