original

[gb-231r1-is01/GB_2.3_IS01.git] / cts / apps / CtsVerifier / jni / audioquality / Window.cpp

diff --git a/cts/apps/CtsVerifier/jni/audioquality/Window.cpp b/cts/apps/CtsVerifier/jni/audioquality/Window.cpp
new file mode 100644 (file)
index 0000000..8e89ed4
--- /dev/null
+++ b/cts/apps/CtsVerifier/jni/audioquality/Window.cpp
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+#include "Window.h"
+
+#include <stdlib.h>
+#include <math.h>
+
+void Window::windowCreate(int size) {
+    if (mWindowWeights && (mWindowSize < size)) {
+        delete [] mWindowWeights;
+        mWindowWeights = NULL;
+        mWindowSize = 0;
+    }
+    if (!mWindowWeights) {
+        mWindowWeights = new float[size];
+    }
+    if (mWindowSize != size) {
+        double arg = M_PI * 2.0 / size;
+        mWindowSize = size;
+        for (int i = 0; i < size; ++i) {
+            mWindowWeights[i] = 0.5 - (0.5 * cos((i + 0.5) * arg));
+        }
+    }
+}
+
+void Window::windowCleanup() {
+    mWindowSize = 0;
+    delete [] mWindowWeights;
+    mWindowWeights = NULL;
+}
+
+/* Multiply the signal in data by the window weights.  Place the
+   resulting mWindowSize floating-point values in output.  If preemp
+   is != 0.0, apply a 1st-order preemphasis filter, and assume that
+   there are mWindowSize+1 samples available in data. */
+void Window::window(short* data, float* output, float preemp) {
+    if (preemp == 0.0) {
+        for (int i = 0; i < mWindowSize; ++i)
+            output[i] = data[i] * mWindowWeights[i];
+    } else {
+        for (int i = 0; i < mWindowSize; ++i)
+            output[i] = (data[i+1] - (preemp * data[i])) * mWindowWeights[i];
+    }
+}
+