Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 116 insertions, 0 deletions

diff --git a/third_party/libwebrtc/modules/audio_coding/neteq/buffer_level_filter_unittest.cc b/third_party/libwebrtc/modules/audio_coding/neteq/buffer_level_filter_unittest.cc
new file mode 100644
index 0000000000..6773e96f58
--- /dev/null
+++ b/third_party/libwebrtc/modules/audio_coding/neteq/buffer_level_filter_unittest.cc
@@ -0,0 +1,116 @@
+/*
+ *  Copyright (c) 2012 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.
+ */
+
+// Unit tests for BufferLevelFilter class.
+
+#include "modules/audio_coding/neteq/buffer_level_filter.h"
+
+#include <math.h>  // Access to pow function.
+
+#include "rtc_base/strings/string_builder.h"
+#include "test/gtest.h"
+
+namespace webrtc {
+
+TEST(BufferLevelFilter, CreateAndDestroy) {
+  BufferLevelFilter* filter = new BufferLevelFilter();
+  EXPECT_EQ(0, filter->filtered_current_level());
+  delete filter;
+}
+
+TEST(BufferLevelFilter, ConvergenceTest) {
+  BufferLevelFilter filter;
+  for (int times = 10; times <= 50; times += 10) {
+    for (int value = 100; value <= 200; value += 10) {
+      filter.Reset();
+      filter.SetTargetBufferLevel(20);  // Makes filter coefficient 251/256.
+      rtc::StringBuilder ss;
+      ss << "times = " << times << ", value = " << value;
+      SCOPED_TRACE(ss.str());  // Print out the parameter values on failure.
+      for (int i = 0; i < times; ++i) {
+        filter.Update(value, 0 /* time_stretched_samples */);
+      }
+      // Expect the filtered value to be (theoretically)
+      // (1 - (251/256) ^ `times`) * `value`.
+      double expected_value_double = (1 - pow(251.0 / 256.0, times)) * value;
+      int expected_value = static_cast<int>(expected_value_double);
+
+      // The actual value may differ slightly from the expected value due to
+      // intermediate-stage rounding errors in the filter implementation.
+      // This is why we have to use EXPECT_NEAR with a tolerance of +/-1.
+      EXPECT_NEAR(expected_value, filter.filtered_current_level(), 1);
+    }
+  }
+}
+
+// Verify that target buffer level impacts on the filter convergence.
+TEST(BufferLevelFilter, FilterFactor) {
+  BufferLevelFilter filter;
+  // Update 10 times with value 100.
+  const int kTimes = 10;
+  const int kValue = 100;
+
+  filter.SetTargetBufferLevel(60);  // Makes filter coefficient 252/256.
+  for (int i = 0; i < kTimes; ++i) {
+    filter.Update(kValue, 0 /* time_stretched_samples */);
+  }
+  // Expect the filtered value to be
+  // (1 - (252/256) ^ `kTimes`) * `kValue`.
+  int expected_value = 15;
+  EXPECT_EQ(expected_value, filter.filtered_current_level());
+
+  filter.Reset();
+  filter.SetTargetBufferLevel(140);  // Makes filter coefficient 253/256.
+  for (int i = 0; i < kTimes; ++i) {
+    filter.Update(kValue, 0 /* time_stretched_samples */);
+  }
+  // Expect the filtered value to be
+  // (1 - (253/256) ^ `kTimes`) * `kValue`.
+  expected_value = 11;
+  EXPECT_EQ(expected_value, filter.filtered_current_level());
+
+  filter.Reset();
+  filter.SetTargetBufferLevel(160);  // Makes filter coefficient 254/256.
+  for (int i = 0; i < kTimes; ++i) {
+    filter.Update(kValue, 0 /* time_stretched_samples */);
+  }
+  // Expect the filtered value to be
+  // (1 - (254/256) ^ `kTimes`) * `kValue`.
+  expected_value = 8;
+  EXPECT_EQ(expected_value, filter.filtered_current_level());
+}
+
+TEST(BufferLevelFilter, TimeStretchedSamples) {
+  BufferLevelFilter filter;
+  filter.SetTargetBufferLevel(20);  // Makes filter coefficient 251/256.
+  // Update 10 times with value 100.
+  const int kTimes = 10;
+  const int kValue = 100;
+  const int kTimeStretchedSamples = 3;
+  for (int i = 0; i < kTimes; ++i) {
+    filter.Update(kValue, 0);
+  }
+  // Expect the filtered value to be
+  // (1 - (251/256) ^ `kTimes`) * `kValue`.
+  const int kExpectedValue = 18;
+  EXPECT_EQ(kExpectedValue, filter.filtered_current_level());
+
+  // Update filter again, now with non-zero value for packet length.
+  // Set the current filtered value to be the input, in order to isolate the
+  // impact of `kTimeStretchedSamples`.
+  filter.Update(filter.filtered_current_level(), kTimeStretchedSamples);
+  EXPECT_EQ(kExpectedValue - kTimeStretchedSamples,
+            filter.filtered_current_level());
+  // Try negative value and verify that we come back to the previous result.
+  filter.Update(filter.filtered_current_level(), -kTimeStretchedSamples);
+  EXPECT_EQ(kExpectedValue, filter.filtered_current_level());
+}
+
+}  // namespace webrtc