Adding fraction of filter divergence in AEC metrics.

webrtc/modules/audio_processing/utility/mean_calculator_unittest.cc

+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+#include "webrtc/modules/audio_processing/utility/mean_calculator.h"
+
+namespace webrtc {
+
+TEST(MeanCalculatorTest, Fullness) {

[peah-webrtc, 2016/03/14 09:12:53]

There should also be a test that checks that the correct values of the mean are
computed.

[minyue-webrtc, 2016/03/14 14:51:42]

renamed the test

[peah-webrtc, 2016/03/15 09:18:41]

I think you should have a separate test that tests the correctness of the mean
and one that only tests the IsWindowFull functionality.

+  const size_t kWindowLength = 10;
+  MeanCalculator mean_calculator(kWindowLength);
+  size_t i = 0;
+  for (; i < kWindowLength; ++i) {
+    EXPECT_FALSE(mean_calculator.IsWindowFull()) << i;
+    EXPECT_FALSE(mean_calculator.GetMean());
+    mean_calculator.AddSample(static_cast<float>(i));
+  }
+  for (; i < 3 * kWindowLength; ++i) {
+    EXPECT_TRUE(mean_calculator.IsWindowFull());
+    // (i - kWindowLength) ... (i - 1)
+    EXPECT_EQ(i - 0.5 * (1 + kWindowLength), *mean_calculator.GetMean());
+    mean_calculator.AddSample(static_cast<float>(i));
+  }
+}
+
+TEST(MeanCalculatorTest, Flush) {
+  const size_t kWindowLength = 10;
+  MeanCalculator mean_calculator(kWindowLength);
+  for (size_t i = 0; i < kWindowLength; ++i) {
+    mean_calculator.AddSample(static_cast<float>(i));
+  }
+  EXPECT_TRUE(mean_calculator.IsWindowFull());
+  mean_calculator.Flush();
+
+  for (size_t i = 0; i < kWindowLength; ++i) {
+    EXPECT_FALSE(mean_calculator.IsWindowFull());
+    EXPECT_FALSE(mean_calculator.GetMean());
+    mean_calculator.AddSample(static_cast<float>(i));
+  }
+  EXPECT_TRUE(mean_calculator.IsWindowFull());
+  EXPECT_EQ(0.5 * (kWindowLength - 1), *mean_calculator.GetMean());
+}
+
+}  // namespace webrt