media/base/media_switches.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "media/base/media_switches.h"
   6
   7 namespace switches {
   8
   9 // Allow users to specify a custom buffer size for debugging purpose.
  10 const char kAudioBufferSize[] = "audio-buffer-size";
  11
  12 // Enable EAC3 playback in MSE.
  13 const char kEnableEac3Playback[] = "enable-eac3-playback";
  14
  15 // Enables Opus playback in media elements.
  16 const char kEnableOpusPlayback[] = "enable-opus-playback";
  17
  18 // Disables VP8 Alpha playback in media elements.
  19 const char kDisableVp8AlphaPlayback[] = "disable-vp8-alpha-playback";
  20
  21 // Set number of threads to use for video decoding.
  22 const char kVideoThreads[] = "video-threads";
  23
  24 // Enables MP3 stream parser for Media Source Extensions.
  25 const char kEnableMP3StreamParser[] = "enable-mp3-stream-parser";
  26
  27 #if defined(OS_ANDROID)
  28 // Disables the infobar popup for accessing protected media identifier.
  29 const char kDisableInfobarForProtectedMediaIdentifier[] =
  30     "disable-infobar-for-protected-media-identifier";
  31
  32 // Enables use of non-compositing MediaDrm decoding by default for Encrypted
  33 // Media Extensions implementation.
  34 const char kMediaDrmEnableNonCompositing[] = "mediadrm-enable-non-compositing";
  35 #endif
  36
  37 #if defined(GOOGLE_TV)
  38 // Use external video surface for video with more than or equal pixels to
  39 // specified value. For example, value of 0 will enable external video surface
  40 // for all videos, and value of 921600 (=1280*720) will enable external video
  41 // surface for 720p video and larger.
  42 const char kUseExternalVideoSurfaceThresholdInPixels[] =
  43     "use-external-video-surface-threshold-in-pixels";
  44 #endif
  45
  46 #if defined(OS_LINUX) || defined(OS_FREEBSD) || defined(OS_SOLARIS)
  47 // The Alsa device to use when opening an audio input stream.
  48 const char kAlsaInputDevice[] = "alsa-input-device";
  49 // The Alsa device to use when opening an audio stream.
  50 const char kAlsaOutputDevice[] = "alsa-output-device";
  51 #endif
  52
  53 #if defined(OS_MACOSX)
  54 // Unlike other platforms, OSX requires CoreAudio calls to happen on the main
  55 // thread of the process.  Provide a way to disable this until support is well
  56 // tested.  See http://crbug.com/158170.
  57 // TODO(dalecurtis): Remove this once we're sure nothing has exploded.
  58 const char kDisableMainThreadAudio[] = "disable-main-thread-audio";
  59 // AVFoundation is available in versions 10.7 and onwards, and is to be used
  60 // http://crbug.com/288562 for both audio and video device monitoring and for
  61 // video capture. Being a dynamically loaded NSBundle and library, it hits the
  62 // Chrome startup time (http://crbug.com/311325 and http://crbug.com/311437);
  63 // until development is finished and the library load time issue is solved, the
  64 // usage of this library is hidden behind this flag.
  65 const char kEnableAVFoundation[] = "enable-avfoundation";
  66 #endif
  67
  68 #if defined(OS_WIN)
  69 // Use exclusive mode audio streaming for Windows Vista and higher.
  70 // Leads to lower latencies for audio streams which uses the
  71 // AudioParameters::AUDIO_PCM_LOW_LATENCY audio path.
  72 // See http://msdn.microsoft.com/en-us/library/windows/desktop/dd370844.aspx
  73 // for details.
  74 const char kEnableExclusiveAudio[] = "enable-exclusive-audio";
  75
  76 // Used to troubleshoot problems with different video capture implementations
  77 // on Windows.  By default we use the Media Foundation API on Windows 7 and up,
  78 // but specifying this switch will force use of DirectShow always.
  79 // See bug: http://crbug.com/268412
  80 const char kForceDirectShowVideoCapture[] = "force-directshow";
  81
  82 // Use Windows WaveOut/In audio API even if Core Audio is supported.
  83 const char kForceWaveAudio[] = "force-wave-audio";
  84
  85 // Instead of always using the hardware channel layout, check if a driver
  86 // supports the source channel layout.  Avoids outputting empty channels and
  87 // permits drivers to enable stereo to multichannel expansion.  Kept behind a
  88 // flag since some drivers lie about supported layouts and hang when used.  See
  89 // http://crbug.com/259165 for more details.
  90 const char kTrySupportedChannelLayouts[] = "try-supported-channel-layouts";
  91
  92 // Number of buffers to use for WaveOut.
  93 const char kWaveOutBuffers[] = "waveout-buffers";
  94 #endif
  95
  96 #if defined(USE_CRAS)
  97 // Use CRAS, the ChromeOS audio server.
  98 const char kUseCras[] = "use-cras";
  99 #endif
 100
 101 }  // namespace switches