Added an "enable-audio-processor" flag and WebRtcAudioProcessor class

content/renderer/media/media_stream_audio_processor_unittest.cc

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/command_line.h"
+#include "base/file_util.h"
+#include "base/files/file_path.h"
+#include "base/logging.h"
+#include "base/path_service.h"
+#include "base/time/time.h"
+#include "content/public/common/content_switches.h"
+#include "content/renderer/media/media_stream_audio_processor.h"
+#include "content/renderer/media/rtc_media_constraints.h"
+#include "media/audio/audio_parameters.h"
+#include "media/base/audio_bus.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/libjingle/source/talk/app/webrtc/mediastreaminterface.h"
+
+using ::testing::_;
+using ::testing::AnyNumber;
+using ::testing::AtLeast;
+using ::testing::Return;
+
+namespace content {
+
+namespace {
+
+#if defined(ANDROID)
+const int kAudioProcessingSampleRate = 16000;
+#else
+const int kAudioProcessingSampleRate = 32000;
+#endif
+const int kAudioProcessingNumberOfChannel = 1;
+
+// The number of packers used for testing.
+const int kNumberOfPacketsForTest = 100;
+
+void ReadDataFromSpeechFile(char* data, int length) {
+  base::FilePath file;
+  CHECK(PathService::Get(base::DIR_SOURCE_ROOT, &file));
+  file = file.Append(FILE_PATH_LITERAL("media"))
+             .Append(FILE_PATH_LITERAL("test"))
+             .Append(FILE_PATH_LITERAL("data"))
+             .Append(FILE_PATH_LITERAL("speech_16b_stereo_48kHz.raw"));
+  DCHECK(base::PathExists(file));
+  int64 data_file_size64 = 0;
+  DCHECK(file_util::GetFileSize(file, &data_file_size64));
+  EXPECT_EQ(length, file_util::ReadFile(file, data, length));
+  DCHECK(data_file_size64 > length);
+}
+
+void ApplyFixedAudioConstraints(RTCMediaConstraints* constraints) {
+  // Constant constraint keys which enables default audio constraints on
+  // mediastreams with audio.
+  struct {
+    const char* key;
+    const char* value;
+  } static const kDefaultAudioConstraints[] = {
+    { webrtc::MediaConstraintsInterface::kEchoCancellation,
+      webrtc::MediaConstraintsInterface::kValueTrue },
+  #if defined(OS_CHROMEOS) || defined(OS_MACOSX)
+    // Enable the extended filter mode AEC on platforms with known echo issues.
+    { webrtc::MediaConstraintsInterface::kExperimentalEchoCancellation,
+      webrtc::MediaConstraintsInterface::kValueTrue },
+  #endif
+    { webrtc::MediaConstraintsInterface::kAutoGainControl,
+      webrtc::MediaConstraintsInterface::kValueTrue },
+    { webrtc::MediaConstraintsInterface::kExperimentalAutoGainControl,
+      webrtc::MediaConstraintsInterface::kValueTrue },
+    { webrtc::MediaConstraintsInterface::kNoiseSuppression,
+      webrtc::MediaConstraintsInterface::kValueTrue },
+    { webrtc::MediaConstraintsInterface::kHighpassFilter,
+      webrtc::MediaConstraintsInterface::kValueTrue },
+  };
+
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kDefaultAudioConstraints); ++i) {
+    constraints->AddMandatory(kDefaultAudioConstraints[i].key,
+                              kDefaultAudioConstraints[i].value, false);
+  }
+}
+
+}  // namespace
+
+class MediaStreamAudioProcessorTest : public ::testing::Test {
+ public:
+  MediaStreamAudioProcessorTest()
+      : params_(media::AudioParameters::AUDIO_PCM_LOW_LATENCY,
+                media::CHANNEL_LAYOUT_STEREO, 48000, 16, 512) {
+    CommandLine::ForCurrentProcess()->AppendSwitch(
+        switches::kEnableAudioTrackProcessing);
+  }
+
+ protected:
+  // Helper method to save duplicated code.
+  void ProcessDataAndVerifyFormat(MediaStreamAudioProcessor* audio_processor,
+                                  int expected_output_sample_rate,
+                                  int expected_output_channels,
+                                  int expected_output_buffer_size) {
+    // Read the audio data from a file.
+    const int packet_size =
+        params_.frames_per_buffer() * 2 * params_.channels();
+    const size_t length = packet_size * kNumberOfPacketsForTest;
+    scoped_ptr<char[]> capture_data(new char[length]);
+    ReadDataFromSpeechFile(capture_data.get(), length);
+    const int16* data_ptr = reinterpret_cast<const int16*>(capture_data.get());
+    scoped_ptr<media::AudioBus> data_bus = media::AudioBus::Create(
+        params_.channels(), params_.frames_per_buffer());
+    for (int i = 0; i < kNumberOfPacketsForTest; ++i) {
+      data_bus->FromInterleaved(data_ptr, data_bus->frames(), 2);
+      audio_processor->PushCaptureData(data_bus.get());
+
+      // |audio_processor| does nothing when the audio processing is off in
+      // the processor.
+      audio_processor->PushRenderData(
+          data_ptr,
+          params_.sample_rate(), params_.channels(),
+          params_.frames_per_buffer(), base::TimeDelta::FromMilliseconds(10));
+
+      int16* output = NULL;
+      while(audio_processor->ProcessAndConsumeData(
+          base::TimeDelta::FromMilliseconds(10), 255, false, &output)) {
+        EXPECT_TRUE(output != NULL);
+        EXPECT_EQ(audio_processor->OutputFormat().sample_rate(),
+                  expected_output_sample_rate);
+        EXPECT_EQ(audio_processor->OutputFormat().channels(),
+                  expected_output_channels);
+        EXPECT_EQ(audio_processor->OutputFormat().frames_per_buffer(),
+                  expected_output_buffer_size);
+      }
+
+      data_ptr += params_.frames_per_buffer() * params_.channels();
+    }
+  }
+
+  media::AudioParameters params_;
+};
+
+TEST_F(MediaStreamAudioProcessorTest, WithoutAudioProcessing) {
+  // Setup the audio processor with empty constraint.
+  RTCMediaConstraints constraints;
+  MediaStreamAudioProcessor audio_processor(&constraints);
+  audio_processor.SetCaptureFormat(params_);
+  EXPECT_FALSE(audio_processor.has_audio_processing());
+
+  ProcessDataAndVerifyFormat(&audio_processor,
+                             params_.sample_rate(),
+                             params_.channels(),
+                             params_.sample_rate() / 100);
+}
+
+TEST_F(MediaStreamAudioProcessorTest, WithAudioProcessing) {
+  // Setup the audio processor with default constraint.
+  RTCMediaConstraints constraints;
+  ApplyFixedAudioConstraints(&constraints);
+  MediaStreamAudioProcessor audio_processor(&constraints);
+  audio_processor.SetCaptureFormat(params_);
+  EXPECT_TRUE(audio_processor.has_audio_processing());
+
+  ProcessDataAndVerifyFormat(&audio_processor,
+                             kAudioProcessingSampleRate,
+                             kAudioProcessingNumberOfChannel,
+                             kAudioProcessingSampleRate / 100);
+}
+
+}  // namespace content