Adds support for CoreAudioUtil::IsChannelLayoutSupported()

media/audio/win/core_audio_util_win.cc

Index: media/audio/win/core_audio_util_win.cc
diff --git a/media/audio/win/core_audio_util_win.cc b/media/audio/win/core_audio_util_win.cc
index 01c7eee2cd75aa8cb3c94e48c58ca6bc9414c86b..fa515defc48c518f1aa9c2905b06b14ee473fe4e 100644
--- a/media/audio/win/core_audio_util_win.cc
+++ b/media/audio/win/core_audio_util_win.cc
@@ -22,6 +22,8 @@ using base::win::ScopedHandle;
 
 namespace media {
 
+enum { KSAUDIO_SPEAKER_UNSUPPORTED = 0 };
+
 typedef uint32 ChannelConfig;
 
 // Converts Microsoft's channel configuration to ChannelLayout.
@@ -62,11 +64,64 @@ static ChannelLayout ChannelConfigToChannelLayout(ChannelConfig config) {
       DVLOG(2) << "KSAUDIO_SPEAKER_7POINT1_SURROUND=>CHANNEL_LAYOUT_7_1";
       return CHANNEL_LAYOUT_7_1;
     default:
-      DVLOG(2) << "Unsupported channel layout: " << config;
+      DVLOG(2) << "Unsupported channel configuration: " << config;
       return CHANNEL_LAYOUT_UNSUPPORTED;
   }
 }
 
+// TODO(henrika): add mapping for all types in the ChannelLayout enumerator.
+static ChannelConfig ChannelLayoutToChannelConfig(ChannelLayout layout) {
+  switch (layout) {
+    case CHANNEL_LAYOUT_NONE:
+      DVLOG(2) << "CHANNEL_LAYOUT_NONE=>KSAUDIO_SPEAKER_UNSUPPORTED";
+      return KSAUDIO_SPEAKER_UNSUPPORTED;
+    case CHANNEL_LAYOUT_UNSUPPORTED:
+      DVLOG(2) << "CHANNEL_LAYOUT_UNSUPPORTED=>KSAUDIO_SPEAKER_UNSUPPORTED";
+      return KSAUDIO_SPEAKER_UNSUPPORTED;
+    case CHANNEL_LAYOUT_MONO:
+      DVLOG(2) << "CHANNEL_LAYOUT_MONO=>KSAUDIO_SPEAKER_MONO";
+      return KSAUDIO_SPEAKER_MONO;
+    case CHANNEL_LAYOUT_STEREO:
+      DVLOG(2) << "CHANNEL_LAYOUT_STEREO=>KSAUDIO_SPEAKER_STEREO";
+      return KSAUDIO_SPEAKER_STEREO;
+    case CHANNEL_LAYOUT_QUAD:
+      DVLOG(2) << "CHANNEL_LAYOUT_QUAD=>KSAUDIO_SPEAKER_QUAD";
+      return KSAUDIO_SPEAKER_QUAD;
+    case CHANNEL_LAYOUT_4_0:
+      DVLOG(2) << "CHANNEL_LAYOUT_4_0=>KSAUDIO_SPEAKER_SURROUND";
+      return KSAUDIO_SPEAKER_SURROUND;
+    case CHANNEL_LAYOUT_5_1_BACK:
+      DVLOG(2) << "CHANNEL_LAYOUT_5_1_BACK=>KSAUDIO_SPEAKER_5POINT1";
+      return KSAUDIO_SPEAKER_5POINT1;
+    case CHANNEL_LAYOUT_5_1:
+      DVLOG(2) << "CHANNEL_LAYOUT_5_1=>KSAUDIO_SPEAKER_5POINT1_SURROUND";
+      return KSAUDIO_SPEAKER_5POINT1_SURROUND;
+    case CHANNEL_LAYOUT_7_1_WIDE:
+      DVLOG(2) << "CHANNEL_LAYOUT_7_1_WIDE=>KSAUDIO_SPEAKER_7POINT1";
+      return KSAUDIO_SPEAKER_7POINT1;
+    case CHANNEL_LAYOUT_7_1:
+      DVLOG(2) << "CHANNEL_LAYOUT_7_1=>KSAUDIO_SPEAKER_7POINT1_SURROUND";
+      return KSAUDIO_SPEAKER_7POINT1_SURROUND;
+    default:
+      DVLOG(2) << "Unsupported channel layout: " << layout;
+      return KSAUDIO_SPEAKER_UNSUPPORTED;
+  }
+}
+
+static std::ostream& operator<<(std::ostream& os,
+                                const WAVEFORMATPCMEX& format) {
+  os << "wFormatTag: 0x" << std::hex << format.Format.wFormatTag
+     << ", nChannels: " << std::dec << format.Format.nChannels
+     << ", nSamplesPerSec: " << format.Format.nSamplesPerSec
+     << ", nAvgBytesPerSec: " << format.Format.nAvgBytesPerSec
+     << ", nBlockAlign: " << format.Format.nBlockAlign
+     << ", wBitsPerSample: " << format.Format.wBitsPerSample
+     << ", cbSize: " << format.Format.cbSize
+     << ", wValidBitsPerSample: " << format.Samples.wValidBitsPerSample
+     << ", dwChannelMask: 0x" << std::hex << format.dwChannelMask;
+  return os;
+}
+
 bool LoadAudiosesDll() {
   static const wchar_t* const kAudiosesDLL =
       L"%WINDIR%\\system32\\audioses.dll";
@@ -349,16 +404,7 @@ HRESULT CoreAudioUtil::GetSharedModeMixFormat(
   DCHECK_EQ(bytes, sizeof(WAVEFORMATPCMEX));
 
   memcpy(format, format_pcmex, bytes);
-
-  DVLOG(2) << "wFormatTag: 0x" << std::hex << format->Format.wFormatTag
-           << ", nChannels: " << std::dec << format->Format.nChannels
-           << ", nSamplesPerSec: " << format->Format.nSamplesPerSec
-           << ", nAvgBytesPerSec: " << format->Format.nAvgBytesPerSec
-           << ", nBlockAlign: " << format->Format.nBlockAlign
-           << ", wBitsPerSample: " << format->Format.wBitsPerSample
-           << ", cbSize: " << format->Format.cbSize
-           << ", wValidBitsPerSample: " << format->Samples.wValidBitsPerSample
-           << ", dwChannelMask: 0x" << std::hex << format->dwChannelMask;
+  DVLOG(2) << *format;
 
   return hr;
 }
@@ -390,15 +436,60 @@ bool CoreAudioUtil::IsFormatSupported(IAudioClient* client,
   // This log can be triggered both for shared and exclusive modes.
   DLOG_IF(ERROR, hr == AUDCLNT_E_UNSUPPORTED_FORMAT) << "Unsupported format.";
   if (hr == S_FALSE) {
-    DVLOG(2) << "wFormatTag: " << closest_match->Format.wFormatTag
-             << ", nChannels: " << closest_match->Format.nChannels
-             << ", nSamplesPerSec: " << closest_match->Format.nSamplesPerSec
-             << ", wBitsPerSample: " << closest_match->Format.wBitsPerSample;
+    DVLOG(2) << *closest_match;
   }
 
   return (hr == S_OK);
 }
 
+bool CoreAudioUtil::IsChannelLayoutSupported(EDataFlow data_flow, ERole role,
+                                             ChannelLayout channel_layout) {
+  DCHECK(IsSupported());
+
+  // First, get the preferred mixing format for shared mode streams.
+
+  ScopedComPtr<IAudioClient> client(CreateDefaultClient(data_flow, role));
+  if (!client)
+    return false;
+
+  WAVEFORMATPCMEX format;
+  HRESULT hr = CoreAudioUtil::GetSharedModeMixFormat(client, &format);
+  if (FAILED(hr))
+    return false;
+
+  // Next, check if it is possible to use an alternative format where the
+  // channel layout (and possibly number of channels) is modified.
+
+  // Convert generic channel layout into Windows-specific channel configuration.
+  ChannelConfig new_config = ChannelLayoutToChannelConfig(channel_layout);
+  if (new_config == KSAUDIO_SPEAKER_UNSUPPORTED) {
+    return false;
+  }
+  format.dwChannelMask = new_config;
+
+  // Modify the format if the new channel layout has changed the number of
+  // utilized channels.
+  const int channels = ChannelLayoutToChannelCount(channel_layout);
+  if (channels != format.Format.nChannels) {
+    format.Format.nChannels = channels;
+    format.Format.nBlockAlign = (format.Format.wBitsPerSample / 8) * channels;
+    format.Format.nAvgBytesPerSec = format.Format.nSamplesPerSec *
+                                    format.Format.nBlockAlign;
+  }
+  DVLOG(2) << format;
+
+  // Some devices can initialize a shared-mode stream with a format that is
+  // not identical to the mix format obtained from the GetMixFormat() method.
+  // However, chances of succeeding increases if we use the same number of
+  // channels and the same sample rate as the mix format. I.e, this call will
+  // return true only in those cases where the audio engine is able to support
+  // an even wider range of shared-mode formats where the installation package
+  // for the audio device includes a local effects (LFX) audio processing
+  // object (APO) that can handle format conversions.
+  return CoreAudioUtil::IsFormatSupported(client, AUDCLNT_SHAREMODE_SHARED,
+                                          &format);
+}
+
 HRESULT CoreAudioUtil::GetDevicePeriod(IAudioClient* client,
                                        AUDCLNT_SHAREMODE share_mode,
                                        REFERENCE_TIME* device_period) {