Adding DTX controller to audio network adaptor.

webrtc/modules/audio_coding/audio_network_adaptor/dtx_controller_unittest.cc

Index: webrtc/modules/audio_coding/audio_network_adaptor/dtx_controller_unittest.cc
diff --git a/webrtc/modules/audio_coding/audio_network_adaptor/dtx_controller_unittest.cc b/webrtc/modules/audio_coding/audio_network_adaptor/dtx_controller_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e8fda9efe0820e018c7580805fba353a803a2fb3
--- /dev/null
+++ b/webrtc/modules/audio_coding/audio_network_adaptor/dtx_controller_unittest.cc
@@ -0,0 +1,86 @@
+/*
+ *  Copyright (c) 2016 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 <memory>
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "webrtc/modules/audio_coding/audio_network_adaptor/dtx_controller.h"
+
+namespace webrtc {
+
+namespace {
+
+constexpr int kDtxEnablingBandwidthBps = 55000;
+constexpr int kDtxDisablingBandwidthBps = 65000;
+constexpr int kMediumBandwidthBps =
+    (kDtxEnablingBandwidthBps + kDtxDisablingBandwidthBps) / 2;
+
+std::unique_ptr<DtxController> CreateController(int initial_dtx_enabled) {

[minyue-webrtc, 2016/09/15 08:00:30]

inspired by other CL, I did further simplification on the test

[hlundin-webrtc, 2016/09/15 11:05:48]

Improved!

+  std::unique_ptr<DtxController> controller(new DtxController(
+      DtxController::Config(initial_dtx_enabled, kDtxEnablingBandwidthBps,
+                            kDtxDisablingBandwidthBps)));
+  return controller;
+}
+
+void CheckDecision(DtxController* controller,
+                   const rtc::Optional<int>& uplink_bandwidth_bps,
+                   bool expected_dtx_enabled) {
+  AudioNetworkAdaptor::EncoderRuntimeConfig config;
+  Controller::NetworkMetrics metrics;
+  metrics.uplink_bandwidth_bps = uplink_bandwidth_bps;
+  controller->MakeDecision(metrics, &config);
+  EXPECT_EQ(rtc::Optional<bool>(expected_dtx_enabled), config.enable_dtx);
+}
+
+}  // namespace
+
+TEST(DtxControllerTest, OutputInitValueWhenUplinkBandwidthUnknown) {
+  constexpr bool kInitialDtxEnabled = true;
+  auto controller = CreateController(kInitialDtxEnabled);
+  CheckDecision(controller.get(), rtc::Optional<int>(), kInitialDtxEnabled);
+}
+
+TEST(DtxControllerTest, TurnOnDtxForLowUplinkBandwidth) {
+  auto controller = CreateController(false);
+  CheckDecision(controller.get(), rtc::Optional<int>(kDtxEnablingBandwidthBps),
+                true);
+}
+
+TEST(DtxControllerTest, TurnOffDtxForHighUplinkBandwidth) {
+  auto controller = CreateController(true);
+  CheckDecision(controller.get(), rtc::Optional<int>(kDtxDisablingBandwidthBps),
+                false);
+}
+
+TEST(DtxControllerTest, MaintainDtxOffForMediumUplinkBandwidth) {
+  auto controller = CreateController(false);
+  CheckDecision(controller.get(), rtc::Optional<int>(kMediumBandwidthBps),
+                false);
+}
+
+TEST(DtxControllerTest, MaintainDtxOnForMediumUplinkBandwidth) {
+  auto controller = CreateController(true);
+  CheckDecision(controller.get(), rtc::Optional<int>(kMediumBandwidthBps),
+                true);
+}
+
+TEST(DtxControllerTest, CheckBehaviorOnChangingUplinkBandwidth) {

[minyue-webrtc, 2016/09/15 08:00:30]

added this test to cover continuous changes of network condition

[hlundin-webrtc, 2016/09/15 11:05:48]

Good!

+  auto controller = CreateController(false);
+  CheckDecision(controller.get(), rtc::Optional<int>(kMediumBandwidthBps),
+                false);
+  CheckDecision(controller.get(), rtc::Optional<int>(kDtxEnablingBandwidthBps),
+                true);
+  CheckDecision(controller.get(), rtc::Optional<int>(kMediumBandwidthBps),
+                true);
+  CheckDecision(controller.get(), rtc::Optional<int>(kDtxDisablingBandwidthBps),
+                false);
+}
+
+}  // namespace webrtc