Reland of WebRTC: Use the MediaStream Recording API for the audio_quality_browsertest.

chrome/browser/media/webrtc/webrtc_audio_quality_browsertest.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 <stddef.h>
 
 #include <ctime>
 
 #include "base/command_line.h"
 #include "base/files/file_enumerator.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/macros.h"
 #include "base/process/launch.h"
 #include "base/process/process.h"
 #include "base/scoped_native_library.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/test/test_file_util.h"
 #include "build/build_config.h"
 #include "chrome/browser/media/webrtc/webrtc_browsertest_audio.h"
 #include "chrome/browser/media/webrtc/webrtc_browsertest_base.h"
 #include "chrome/browser/media/webrtc/webrtc_browsertest_common.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
+#include "chrome/common/pref_names.h"
 #include "chrome/test/base/ui_test_utils.h"
+#include "components/prefs/pref_service.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/test/browser_test_utils.h"
 #include "media/base/audio_parameters.h"
 #include "media/base/media_switches.h"
 #include "net/test/embedded_test_server/embedded_test_server.h"
 #include "testing/perf/perf_test.h"
 
 namespace {
 
 static const base::FilePath::CharType kReferenceFile[] =
-    FILE_PATH_LITERAL("speech_44kHz_16bit_stereo.wav");
+    FILE_PATH_LITERAL("speech_44kHz_16bit_mono.wav");
 
 // The javascript will load the reference file relative to its location,
 // which is in /webrtc on the web server. The files we are looking for are in
 // webrtc/resources in the chrome/test/data folder.
 static const char kReferenceFileRelativeUrl[] =
-    "resources/speech_44kHz_16bit_stereo.wav";
+    "resources/speech_44kHz_16bit_mono.wav";
 
 static const char kWebRtcAudioTestHtmlPage[] =
     "/webrtc/webrtc_audio_quality_test.html";
 
+// How long to record the audio in the receiving peerConnection.
+static const int kCaptureDurationInSeconds = 25;
+
+// The name where the recorded WebM audio file will be saved.
+static const char kWebmRecordingFilename[] = "recording.webm";
+
+// How often to ask the test page whether the audio recording is completed.
+const int kPollingIntervalInMs = 1000;
+
 // For the AGC test, there are 6 speech segments split on silence. If one
 // segment is significantly different in length compared to the same segment in
 // the reference file, there's something fishy going on.
 const int kMaxAgcSegmentDiffMs =
 #if defined(OS_MACOSX)
   // Something is different on Mac; http://crbug.com/477653.
   600;
 #else
   200;
 #endif
 
 #if defined(OS_LINUX) || defined(OS_WIN) || defined(OS_MACOSX)
 #define MAYBE_WebRtcAudioQualityBrowserTest WebRtcAudioQualityBrowserTest
 #else
 // Not implemented on Android, ChromeOS etc.
 #define MAYBE_WebRtcAudioQualityBrowserTest DISABLED_WebRtcAudioQualityBrowserTest
 #endif
 
 }  // namespace
 
 // Test we can set up a WebRTC call and play audio through it.
 //
 // If you're not a googler and want to run this test, you need to provide a
 // pesq binary for your platform (and sox.exe on windows). Read more on how
 // resources are managed in chrome/test/data/webrtc/resources/README.
 //
-// This test will only work on machines that have been configured to record
-// their own input.
-//
 // On Linux:
-// 1. # sudo apt-get install pavucontrol sox
-// 2. For the user who will run the test: # pavucontrol
-// 3. In a separate terminal, # arecord dummy
-// 4. In pavucontrol, go to the recording tab.
-// 5. For the ALSA plugin [aplay]: ALSA Capture from, change from <x> to
-//    <Monitor of x>, where x is whatever your primary sound device is called.
-// 6. Try launching chrome as the target user on the target machine, try
-//    playing, say, a YouTube video, and record with # arecord -f dat tmp.dat.
-//    Verify the recording with aplay (should have recorded what you played
-//    from chrome).
-//
-// Note: the volume for ALL your input devices will be forced to 100% by
-//       running this test on Linux.
+// 1. # sudo apt-get install sox
 //
 // On Mac:
 // TODO(phoglund): download sox from gs instead.
 // 1. Get SoundFlower: http://rogueamoeba.com/freebies/soundflower/download.php
 // 2. Install it + reboot.
 // 3. Install MacPorts (http://www.macports.org/).
 // 4. Install sox: sudo port install sox.
-// 5. (For Chrome bots) Ensure sox and rec are reachable from the env the test
-//    executes in (sox and rec tends to install in /opt/, which generally isn't
-//    in the Chrome bots' env). For instance, run
-//    sudo ln -s /opt/local/bin/rec /usr/local/bin/rec
+// 5. (For Chrome bots) Ensure sox is reachable from the env the test
+//    executes in (sox tends to install in /opt/, which generally isn't in the
+//    Chrome bots' env). For instance, run
 //    sudo ln -s /opt/local/bin/sox /usr/local/bin/sox
-// 6. In Sound Preferences, set both input and output to Soundflower (2ch).
-//    Note: You will no longer hear audio on this machine, and it will no
-//    longer use any built-in mics.
-// 7. Try launching chrome as the target user on the target machine, try
-//    playing, say, a YouTube video, and record with 'rec test.wav trim 0 5'.
-//    Stop the video in chrome and try playing back the file; you should hear
-//    a recording of the video (note; if you play back on the target machine
-//    you must revert the changes in step 3 first).
-//
-// On Windows 7:
-// 1. Control panel > Sound > Manage audio devices.
-// 2. In the recording tab, right-click in an empty space in the pane with the
-//    devices. Tick 'show disabled devices'.
-// 3. You should see a 'stereo mix' device - this is what your speakers output.
-//    If you don't have one, your driver doesn't support stereo mix devices.
-//    Some drivers use different names for the mix device though (like "Wave").
-//    Right click > Properties.
-// 4. Ensure "listen to this device" is unchecked, otherwise you get echo.
-// 5. Ensure the mix device is the default recording device.
-// 6. Launch chrome and try playing a video with sound. You should see
-//    in the volume meter for the mix device. Configure the mix device to have
-//    50 / 100 in level. Also go into the playback tab, right-click Speakers,
-//    and set that level to 50 / 100. Otherwise you will get distortion in
-//    the recording.
 class MAYBE_WebRtcAudioQualityBrowserTest : public WebRtcTestBase {
  public:
   MAYBE_WebRtcAudioQualityBrowserTest() {}
-  void SetUpInProcessBrowserTestFixture() override {
+  void SetUpOnMainThread() override {

[kjellander_chromium, 2017/03/30 19:26:34]

Does moving this to SetUpOnMainThread() do any difference? Do you think it can
solve the problem on Windows? I guess since we cannot repro, it's still worth a
try...

     DetectErrorsInJavaScript();  // Look for errors in our rather complex js.
+    EXPECT_TRUE(base::CreateNewTempDirectory(base::FilePath::StringType(),
+                                             &temp_downloads_dir_));
+    webm_recorded_output_filename_ =
+        temp_downloads_dir_.Append(FILE_PATH_LITERAL("recording.webm"));
+    browser()->profile()->GetPrefs()->SetFilePath(
+        prefs::kDownloadDefaultDirectory, temp_downloads_dir_);
+    browser()->profile()->GetPrefs()->SetBoolean(prefs::kPromptForDownload,
+                                                 false);
   }
 
   void SetUpCommandLine(base::CommandLine* command_line) override {
     EXPECT_FALSE(command_line->HasSwitch(
         switches::kUseFakeUIForMediaStream));
 
     // The WebAudio-based tests don't care what devices are available to
     // getUserMedia, and the getUserMedia-based tests will play back a file
     // through the fake device using using --use-file-for-fake-audio-capture.
     command_line->AppendSwitch(switches::kUseFakeDeviceForMediaStream);
@@ skipping 37 matching lines @@
                         content::WebContents* tab_contents) {
     EXPECT_EQ("ok-muted", ExecuteJavascript(
         "setMediaElementMuted('" + element_id + "', true)", tab_contents));
   }
 
  protected:
   void TestAutoGainControl(const base::FilePath::StringType& reference_filename,
                            const std::string& constraints,
                            const std::string& perf_modifier);
   void SetupAndRecordAudioCall(const base::FilePath& reference_file,
-                               const base::FilePath& recording,
-                               const std::string& constraints,
-                               const base::TimeDelta recording_time);
+                               const base::FilePath& recorded_output_path,
+                               const std::string& constraints);
   void TestWithFakeDeviceGetUserMedia(const std::string& constraints,
                                       const std::string& perf_modifier);
+
+  base::FilePath temp_downloads_dir_;
+  base::FilePath webm_recorded_output_filename_;
 };
 
 namespace {
 
-class AudioRecorder {
- public:
-  AudioRecorder() {}
-  ~AudioRecorder() {}
-
-  // Starts the recording program for the specified duration. Returns true
-  // on success. We record in 16-bit 44.1 kHz Stereo (mostly because that's
-  // what SoundRecorder.exe will give us and we can't change that).
-  bool StartRecording(base::TimeDelta recording_time,
-                      const base::FilePath& output_file) {
-    EXPECT_FALSE(recording_application_.IsValid())
-        << "Tried to record, but is already recording.";
-
-    int duration_sec = static_cast<int>(recording_time.InSeconds());
-    base::CommandLine command_line(base::CommandLine::NO_PROGRAM);
-
-#if defined(OS_WIN)
-    // This disable is required to run SoundRecorder.exe on 64-bit Windows
-    // from a 32-bit binary. We need to load the wow64 disable function from
-    // the DLL since it doesn't exist on Windows XP.
-    base::ScopedNativeLibrary kernel32_lib(base::FilePath(L"kernel32"));
-    if (kernel32_lib.is_valid()) {
-      typedef BOOL (WINAPI* Wow64DisableWow64FSRedirection)(PVOID*);
-      Wow64DisableWow64FSRedirection wow_64_disable_wow_64_fs_redirection;
-      wow_64_disable_wow_64_fs_redirection =
-          reinterpret_cast<Wow64DisableWow64FSRedirection>(
-              kernel32_lib.GetFunctionPointer(
-                  "Wow64DisableWow64FsRedirection"));
-      if (wow_64_disable_wow_64_fs_redirection != NULL) {
-        PVOID* ignored = NULL;
-        wow_64_disable_wow_64_fs_redirection(ignored);
-      }
-    }
-
-    char duration_in_hms[128] = {0};
-    struct tm duration_tm = {0};
-    duration_tm.tm_sec = duration_sec;
-    EXPECT_NE(0u, strftime(duration_in_hms, arraysize(duration_in_hms),
-                           "%H:%M:%S", &duration_tm));
-
-    command_line.SetProgram(
-        base::FilePath(FILE_PATH_LITERAL("SoundRecorder.exe")));
-    command_line.AppendArg("/FILE");
-    command_line.AppendArgPath(output_file);
-    command_line.AppendArg("/DURATION");
-    command_line.AppendArg(duration_in_hms);
-#elif defined(OS_MACOSX)
-    command_line.SetProgram(base::FilePath("rec"));
-    command_line.AppendArg("-b");
-    command_line.AppendArg("16");
-    command_line.AppendArg("-q");
-    command_line.AppendArgPath(output_file);
-    command_line.AppendArg("trim");
-    command_line.AppendArg("0");
-    command_line.AppendArg(base::IntToString(duration_sec));
-#else
-    command_line.SetProgram(base::FilePath("arecord"));
-    command_line.AppendArg("-d");
-    command_line.AppendArg(base::IntToString(duration_sec));
-    command_line.AppendArg("-f");
-    command_line.AppendArg("cd");
-    command_line.AppendArg("-c");
-    command_line.AppendArg("2");
-    command_line.AppendArgPath(output_file);
-#endif
-
-    DVLOG(0) << "Running " << command_line.GetCommandLineString();
-    recording_application_ =
-        base::LaunchProcess(command_line, base::LaunchOptions());
-    return recording_application_.IsValid();
-  }
-
-  // Joins the recording program. Returns true on success.
-  bool WaitForRecordingToEnd() {
-    int exit_code = -1;
-    recording_application_.WaitForExit(&exit_code);
-    return exit_code == 0;
-  }
- private:
-  base::Process recording_application_;
-};
-
-bool ForceMicrophoneVolumeTo100Percent() {
-#if defined(OS_WIN)
-  // Note: the force binary isn't in tools since it's one of our own.
-  base::CommandLine command_line(test::GetReferenceFilesDir().Append(
-      FILE_PATH_LITERAL("force_mic_volume_max.exe")));
-  DVLOG(0) << "Running " << command_line.GetCommandLineString();
-  std::string result;
-  if (!base::GetAppOutput(command_line, &result)) {
-    LOG(ERROR) << "Failed to set source volume: output was " << result;
-    return false;
-  }
-#elif defined(OS_MACOSX)
-  base::CommandLine command_line(
-      base::FilePath(FILE_PATH_LITERAL("osascript")));
-  command_line.AppendArg("-e");
-  command_line.AppendArg("set volume input volume 100");
-  command_line.AppendArg("-e");
-  command_line.AppendArg("set volume output volume 85");
-
-  std::string result;
-  if (!base::GetAppOutput(command_line, &result)) {
-    LOG(ERROR) << "Failed to set source volume: output was " << result;
-    return false;
-  }
-#else
-  // Just force the volume of, say the first 5 devices. A machine will rarely
-  // have more input sources than that. This is way easier than finding the
-  // input device we happen to be using.
-  for (int device_index = 0; device_index < 5; ++device_index) {
-    std::string result;
-    const std::string kHundredPercentVolume = "65536";
-    base::CommandLine command_line(base::FilePath(FILE_PATH_LITERAL("pacmd")));
-    command_line.AppendArg("set-source-volume");
-    command_line.AppendArg(base::IntToString(device_index));
-    command_line.AppendArg(kHundredPercentVolume);
-    DVLOG(0) << "Running " << command_line.GetCommandLineString();
-    if (!base::GetAppOutput(command_line, &result)) {
-      LOG(ERROR) << "Failed to set source volume: output was " << result;
-      return false;
-    }
-  }
-#endif
-  return true;
-}
-
 // Sox is the "Swiss army knife" of audio processing. We mainly use it for
 // silence trimming. See http://sox.sourceforge.net.
 base::CommandLine MakeSoxCommandLine() {
 #if defined(OS_WIN)
   base::FilePath sox_path = test::GetToolForPlatform("sox");
   if (!base::PathExists(sox_path)) {
     LOG(ERROR) << "Missing sox.exe binary in " << sox_path.value()
                << "; you may have to provide this binary yourself.";
     return base::CommandLine(base::CommandLine::NO_PROGRAM);
   }
@@ skipping 40 matching lines @@
   command_line.AppendArg(kTreshold);
   command_line.AppendArg("reverse");
 
   DVLOG(0) << "Running " << command_line.GetCommandLineString();
   std::string result;
   bool ok = base::GetAppOutput(command_line, &result);
   DVLOG(0) << "Output was:\n\n" << result;
   return ok;
 }
 
+// Runs ffmpeg on the captured webm video and writes it to a .wav file.
+bool RunWebmToWavConverter(const base::FilePath& webm_recorded_output_path,
+                           const base::FilePath& wav_recorded_output_path) {
+  const base::FilePath path_to_ffmpeg = test::GetToolForPlatform("ffmpeg");
+  if (!base::PathExists(path_to_ffmpeg)) {
+    LOG(ERROR) << "Missing ffmpeg: should be in " << path_to_ffmpeg.value();
+    return false;
+  }
+
+  // Set up ffmpeg to output at a certain bitrate (-ab). This is hopefully set
+  // high enough to avoid degrading audio quality too much.
+  base::CommandLine ffmpeg_command(path_to_ffmpeg);
+  ffmpeg_command.AppendArg("-i");
+  ffmpeg_command.AppendArgPath(webm_recorded_output_path);
+  ffmpeg_command.AppendArg("-ab");
+  ffmpeg_command.AppendArg("300k");
+  ffmpeg_command.AppendArg("-ar");
+  ffmpeg_command.AppendArg("44100");
+  ffmpeg_command.AppendArg("-y");
+  ffmpeg_command.AppendArgPath(wav_recorded_output_path);
+
+  // We produce an output file that will later be used as an input to the
+  // barcode decoder and frame analyzer tools.
+  DVLOG(0) << "Running " << ffmpeg_command.GetCommandLineString();
+  std::string result;
+  bool ok = base::GetAppOutputAndError(ffmpeg_command, &result);
+  DVLOG(0) << "Output was:\n\n" << result;
+  return ok;
+}
+
 // Looks for 0.2 second audio segments surrounded by silences under 0.3% audio
 // power and splits the input file on those silences. Output files are written
 // according to the output file template (e.g. /tmp/out.wav writes
 // /tmp/out001.wav, /tmp/out002.wav, etc if there are two silence-padded
 // regions in the file). The silences between speech segments must be at
 // least 500 ms for this to be reliable.
 bool SplitFileOnSilence(const base::FilePath& input_file,
                         const base::FilePath& output_file_template) {
   base::CommandLine command_line = MakeSoxCommandLine();
   if (command_line.GetProgram().empty())
@@ skipping 180 matching lines @@
     float difference_in_decibel = AnalyzeOneSegment(ref_segments[i],
                                                     actual_segments[i],
                                                     i);
     std::string trace_name = MakeTraceName(reference_file, i);
     perf_test::PrintResult("agc_energy_diff", perf_modifier, trace_name,
                            difference_in_decibel, "dB", false);
   }
 }
 
 void ComputeAndPrintPesqResults(const base::FilePath& reference_file,
-                                const base::FilePath& recording,
+                                const base::FilePath& recorded_output_path,
                                 const std::string& perf_modifier) {
   base::FilePath trimmed_reference = CreateTemporaryWaveFile();
   base::FilePath trimmed_recording = CreateTemporaryWaveFile();
 
   ASSERT_TRUE(RemoveSilence(reference_file, trimmed_reference));
-  ASSERT_TRUE(RemoveSilence(recording, trimmed_recording));
+  ASSERT_TRUE(RemoveSilence(recorded_output_path, trimmed_recording));
 
   std::string raw_mos;
   std::string mos_lqo;
   bool succeeded = RunPesq(trimmed_reference, trimmed_recording, 16000,
                            &raw_mos, &mos_lqo);
   EXPECT_TRUE(succeeded) << "Failed to run PESQ.";
   if (succeeded) {
     perf_test::PrintResult(
         "audio_pesq", perf_modifier, "raw_mos", raw_mos, "score", true);
     perf_test::PrintResult(
         "audio_pesq", perf_modifier, "mos_lqo", mos_lqo, "score", true);
   }
 
   DeleteFileUnlessTestFailed(trimmed_reference, false);
   DeleteFileUnlessTestFailed(trimmed_recording, false);
 }
 
 }  // namespace
 
-// Sets up a two-way WebRTC call and records its output to |recording|, using
-// getUserMedia.
+// Sets up a two-way WebRTC call and records its output to
+// |recorded_output_path|, using getUserMedia.
 //
 // |reference_file| should have at least five seconds of silence in the
 // beginning: otherwise all the reference audio will not be picked up by the
 // recording. Note that the reference file will start playing as soon as the
 // audio device is up following the getUserMedia call in the left tab. The time
 // it takes to negotiate a call isn't deterministic, but five seconds should be
 // plenty of time. Similarly, the recording time should be enough to catch the
 // whole reference file. If you then silence-trim the reference file and actual
 // file, you should end up with two time-synchronized files.
 void MAYBE_WebRtcAudioQualityBrowserTest::SetupAndRecordAudioCall(
     const base::FilePath& reference_file,
-    const base::FilePath& recording,
-    const std::string& constraints,
-    const base::TimeDelta recording_time) {
+    const base::FilePath& recorded_output_path,
+    const std::string& constraints) {
   ASSERT_TRUE(embedded_test_server()->Start());
   ASSERT_TRUE(test::HasReferenceFilesInCheckout());
-  ASSERT_TRUE(ForceMicrophoneVolumeTo100Percent());
 
   ConfigureFakeDeviceToPlayFile(reference_file);
 
   // Create a two-way call. Mute one of the receivers though; that way it will
   // be receiving audio bytes, but we will not be playing out of both elements.
   GURL test_page = embedded_test_server()->GetURL(kWebRtcAudioTestHtmlPage);
   content::WebContents* left_tab =
       OpenPageAndGetUserMediaInNewTabWithConstraints(test_page, constraints);
   SetupPeerconnectionWithLocalStream(left_tab);
   MuteMediaElement("remote-view", left_tab);
 
   content::WebContents* right_tab =
       OpenPageAndGetUserMediaInNewTabWithConstraints(test_page, constraints);
   SetupPeerconnectionWithLocalStream(right_tab);
 
-  AudioRecorder recorder;
-  ASSERT_TRUE(recorder.StartRecording(recording_time, recording));
-
   NegotiateCall(left_tab, right_tab);
 
-  ASSERT_TRUE(recorder.WaitForRecordingToEnd());
-  DVLOG(0) << "Done recording to " << recording.value() << std::endl;
+  EXPECT_EQ(
+      "ok-capturing",
+      ExecuteJavascript(
+          base::StringPrintf("startAudioCapture(%d, \"%s\");",
+                             kCaptureDurationInSeconds, kWebmRecordingFilename),
+          right_tab));
+
+  EXPECT_TRUE(test::PollingWaitUntil("testIsDoneCapturing();", "true",
+                                     right_tab, kPollingIntervalInMs));
 
   HangUp(left_tab);
+
+  RunWebmToWavConverter(webm_recorded_output_filename_, recorded_output_path);
+  DeleteFileUnlessTestFailed(temp_downloads_dir_, true);
+
+  DVLOG(0) << "Done recording to " << recorded_output_path.MaybeAsASCII();
 }
 
 void MAYBE_WebRtcAudioQualityBrowserTest::TestWithFakeDeviceGetUserMedia(
     const std::string& constraints,
     const std::string& perf_modifier) {
   if (OnWin8()) {
     // http://crbug.com/379798.
     LOG(ERROR) << "This test is not implemented for Windows XP/Win8.";
     return;
   }
 
   base::FilePath reference_file =
       test::GetReferenceFilesDir().Append(kReferenceFile);
-  base::FilePath recording = CreateTemporaryWaveFile();
+  base::FilePath recorded_output_path = CreateTemporaryWaveFile();
 
   ASSERT_NO_FATAL_FAILURE(SetupAndRecordAudioCall(
-      reference_file, recording, constraints,
-      base::TimeDelta::FromSeconds(30)));
+      reference_file, recorded_output_path, constraints));
 
-  ComputeAndPrintPesqResults(reference_file, recording, perf_modifier);
-  DeleteFileUnlessTestFailed(recording, false);
+  ComputeAndPrintPesqResults(reference_file, recorded_output_path,
+                             perf_modifier);
+  DeleteFileUnlessTestFailed(recorded_output_path, false);
 }
 
 IN_PROC_BROWSER_TEST_F(MAYBE_WebRtcAudioQualityBrowserTest,
                        MANUAL_TestCallQualityWithAudioFromFakeDevice) {
   TestWithFakeDeviceGetUserMedia(kAudioOnlyCallConstraints, "_getusermedia");
 }
 
 IN_PROC_BROWSER_TEST_F(MAYBE_WebRtcAudioQualityBrowserTest,
                        MANUAL_TestCallQualityWithAudioFromWebAudio) {
   if (OnWin8()) {
     // http://crbug.com/379798.
     LOG(ERROR) << "This test is not implemented for Windows XP/Win8.";
     return;
   }
   ASSERT_TRUE(test::HasReferenceFilesInCheckout());
   ASSERT_TRUE(embedded_test_server()->Start());
 
-  ASSERT_TRUE(ForceMicrophoneVolumeTo100Percent());
-
   content::WebContents* left_tab =
       OpenPageWithoutGetUserMedia(kWebRtcAudioTestHtmlPage);
   content::WebContents* right_tab =
       OpenPageWithoutGetUserMedia(kWebRtcAudioTestHtmlPage);
 
   AddAudioFileToWebAudio(kReferenceFileRelativeUrl, left_tab);
 
   NegotiateCall(left_tab, right_tab);
 
-  base::FilePath recording = CreateTemporaryWaveFile();
-
-  // Note: the sound clip is 21.6 seconds: record for 25 seconds to get some
-  // safety margins on each side.
-  AudioRecorder recorder;
-  ASSERT_TRUE(recorder.StartRecording(base::TimeDelta::FromSeconds(25),
-                                      recording));
+  const base::FilePath recorded_output_path = CreateTemporaryWaveFile();
 
   PlayAudioFileThroughWebAudio(left_tab);
 
-  ASSERT_TRUE(recorder.WaitForRecordingToEnd());
-  DVLOG(0) << "Done recording to " << recording.value() << std::endl;
+  EXPECT_EQ(
+      "ok-capturing",
+      ExecuteJavascript(
+          base::StringPrintf("startAudioCapture(%d, \"%s\");",
+                             kCaptureDurationInSeconds, kWebmRecordingFilename),
+          right_tab));
+
+  EXPECT_TRUE(test::PollingWaitUntil("testIsDoneCapturing();", "true",
+                                     right_tab, kPollingIntervalInMs));
 
   HangUp(left_tab);
 
+  RunWebmToWavConverter(webm_recorded_output_filename_, recorded_output_path);
+  DeleteFileUnlessTestFailed(temp_downloads_dir_, true);
+
+  DVLOG(0) << "Done recording to " << recorded_output_path.MaybeAsASCII();
+
   // Compare with the reference file on disk (this is the same file we played
   // through WebAudio earlier).
   base::FilePath reference_file =
       test::GetReferenceFilesDir().Append(kReferenceFile);
-  ComputeAndPrintPesqResults(reference_file, recording, "_webaudio");
+  ComputeAndPrintPesqResults(reference_file, recorded_output_path, "_webaudio");
 }
 
 /**
  * The auto gain control test plays a file into the fake microphone. Then it
  * sets up a one-way WebRTC call with audio only and records Chrome's output on
  * the receiving side using the audio loopback provided by the quality test
  * (see the class comments for more details).
  *
  * Then both the recording and reference file are split on silence. This creates
  * a number of segments with speech in them. The reason for this is to provide
@@ skipping 23 matching lines @@
     const base::FilePath::StringType& reference_filename,
     const std::string& constraints,
     const std::string& perf_modifier) {
   if (OnWin8()) {
     // http://crbug.com/379798.
     LOG(ERROR) << "This test is not implemented for Windows XP/Win8.";
     return;
   }
   base::FilePath reference_file =
       test::GetReferenceFilesDir().Append(reference_filename);
-  base::FilePath recording = CreateTemporaryWaveFile();
+  base::FilePath recorded_output_path = CreateTemporaryWaveFile();
 
   ASSERT_NO_FATAL_FAILURE(SetupAndRecordAudioCall(
-      reference_file, recording, constraints,
-      base::TimeDelta::FromSeconds(30)));
+      reference_file, recorded_output_path, constraints));
 
   base::ScopedTempDir split_ref_files;
   ASSERT_TRUE(split_ref_files.CreateUniqueTempDir());
   ASSERT_NO_FATAL_FAILURE(
       SplitFileOnSilenceIntoDir(reference_file, split_ref_files.GetPath()));
   std::vector<base::FilePath> ref_segments =
       ListWavFilesInDir(split_ref_files.GetPath());
 
   base::ScopedTempDir split_actual_files;
   ASSERT_TRUE(split_actual_files.CreateUniqueTempDir());
-  ASSERT_NO_FATAL_FAILURE(
-      SplitFileOnSilenceIntoDir(recording, split_actual_files.GetPath()));
+  ASSERT_NO_FATAL_FAILURE(SplitFileOnSilenceIntoDir(
+      recorded_output_path, split_actual_files.GetPath()));
 
   // Keep the recording and split files if the analysis fails.
   base::FilePath actual_files_dir = split_actual_files.Take();
   std::vector<base::FilePath> actual_segments =
       ListWavFilesInDir(actual_files_dir);
 
   AnalyzeSegmentsAndPrintResult(
       ref_segments, actual_segments, reference_file, perf_modifier);
 
-  DeleteFileUnlessTestFailed(recording, false);
+  DeleteFileUnlessTestFailed(recorded_output_path, false);
   DeleteFileUnlessTestFailed(actual_files_dir, true);
 }
 
 // The AGC should apply non-zero gain here.
 IN_PROC_BROWSER_TEST_F(MAYBE_WebRtcAudioQualityBrowserTest,
                        MANUAL_TestAutoGainControlOnLowAudio) {
   ASSERT_NO_FATAL_FAILURE(TestAutoGainControl(
       kReferenceFile, kAudioOnlyCallConstraints, "_with_agc"));
 }
 
 // Since the AGC is off here there should be no gain at all.
 IN_PROC_BROWSER_TEST_F(MAYBE_WebRtcAudioQualityBrowserTest,
                        MANUAL_TestAutoGainIsOffWithAudioProcessingOff) {
   const char* kAudioCallWithoutAudioProcessing =
       "{audio: { mandatory: { echoCancellation: false } } }";
   ASSERT_NO_FATAL_FAILURE(TestAutoGainControl(
       kReferenceFile, kAudioCallWithoutAudioProcessing, "_no_agc"));
 }