dom/media/CubebUtils.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #if !defined(CubebUtils_h_)
   8 #  define CubebUtils_h_
   9
  10 #  include "cubeb/cubeb.h"
  11
  12 #  include "AudioSampleFormat.h"
  13 #  include "nsString.h"
  14 #  include "nsISupportsImpl.h"
  15
  16 class AudioDeviceInfo;
  17
  18 MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(cubeb_stream_prefs)
  19
  20 namespace mozilla {
  21
  22 class CallbackThreadRegistry;
  23
  24 namespace CubebUtils {
  25
  26 typedef cubeb_devid AudioDeviceID;
  27
  28 template <AudioSampleFormat N>
  29 struct ToCubebFormat {
  30   static const cubeb_sample_format value = CUBEB_SAMPLE_FLOAT32NE;
  31 };
  32
  33 template <>
  34 struct ToCubebFormat<AUDIO_FORMAT_S16> {
  35   static const cubeb_sample_format value = CUBEB_SAMPLE_S16NE;
  36 };
  37
  38 class CubebHandle {
  39  public:
  40   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(CubebHandle)
  41   explicit CubebHandle(cubeb* aCubeb) : mCubeb(aCubeb) {
  42     MOZ_RELEASE_ASSERT(mCubeb);
  43   };
  44   CubebHandle(const CubebHandle&) = delete;
  45   cubeb* Context() const { return mCubeb.get(); }
  46
  47  private:
  48   struct CubebDeletePolicy {
  49     void operator()(cubeb* aCubeb) { cubeb_destroy(aCubeb); }
  50   };
  51   const UniquePtr<cubeb, CubebDeletePolicy> mCubeb;
  52   ~CubebHandle() = default;
  53 };
  54
  55 // Initialize Audio Library. Some Audio backends require initializing the
  56 // library before using it.
  57 void InitLibrary();
  58
  59 // Shutdown Audio Library. Some Audio backends require shutting down the
  60 // library after using it.
  61 void ShutdownLibrary();
  62
  63 bool SandboxEnabled();
  64
  65 // Returns the maximum number of channels supported by the audio hardware.
  66 uint32_t MaxNumberOfChannels();
  67
  68 // Get the sample rate the hardware/mixer runs at. Thread safe.
  69 uint32_t PreferredSampleRate(bool aShouldResistFingerprinting);
  70
  71 // Initialize a cubeb stream. A pass through wrapper for cubeb_stream_init,
  72 // that can simulate streams that are very slow to start, by setting the pref
  73 // media.cubeb.slow_stream_init_ms.
  74 int CubebStreamInit(cubeb* context, cubeb_stream** stream,
  75                     char const* stream_name, cubeb_devid input_device,
  76                     cubeb_stream_params* input_stream_params,
  77                     cubeb_devid output_device,
  78                     cubeb_stream_params* output_stream_params,
  79                     uint32_t latency_frames, cubeb_data_callback data_callback,
  80                     cubeb_state_callback state_callback, void* user_ptr);
  81
  82 enum Side { Input, Output };
  83
  84 double GetVolumeScale();
  85 bool GetFirstStream();
  86 RefPtr<CubebHandle> GetCubeb();
  87 void ReportCubebStreamInitFailure(bool aIsFirstStream);
  88 void ReportCubebBackendUsed();
  89 uint32_t GetCubebPlaybackLatencyInMilliseconds();
  90 uint32_t GetCubebMTGLatencyInFrames(cubeb_stream_params* params);
  91 bool CubebLatencyPrefSet();
  92 void GetCurrentBackend(nsAString& aBackend);
  93 cubeb_stream_prefs GetDefaultStreamPrefs(cubeb_device_type aType);
  94 char* GetForcedOutputDevice();
  95 // No-op on all platforms but Android, where it tells the device's AudioManager
  96 // to switch to "communication mode", which might change audio routing,
  97 // bluetooth communication type, etc.
  98 void SetInCommunication(bool aInCommunication);
  99 // Returns true if the output streams should be routed like a stream containing
 100 // voice data, and not generic audio. This can influence audio processing and
 101 // device selection.
 102 bool RouteOutputAsVoice();
 103 // Returns, in seconds, the roundtrip latency Gecko thinks there is between the
 104 // default input and output devices. This is for diagnosing purposes, the
 105 // latency figures are best used directly from the cubeb streams themselves, as
 106 // the devices being used matter. This is blocking.
 107 bool EstimatedRoundTripLatencyDefaultDevices(double* aMean, double* aStdDev);
 108
 109 #  ifdef MOZ_WIDGET_ANDROID
 110 int32_t AndroidGetAudioOutputSampleRate();
 111 int32_t AndroidGetAudioOutputFramesPerBuffer();
 112 #  endif
 113
 114 #  ifdef ENABLE_SET_CUBEB_BACKEND
 115 void ForceSetCubebContext(cubeb* aCubebContext);
 116 #  endif
 117 }  // namespace CubebUtils
 118 }  // namespace mozilla
 119
 120 #endif  // CubebUtils_h_