1 files changed, 567 insertions, 0 deletions
diff --git a/dom/media/platforms/PlatformDecoderModule.h b/dom/media/platforms/PlatformDecoderModule.h
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+++ b/dom/media/platforms/PlatformDecoderModule.h
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#if !defined(PlatformDecoderModule_h_)
+#  define PlatformDecoderModule_h_
+
+#  include <queue>
+
+#  include "DecoderDoctorLogger.h"
+#  include "GMPCrashHelper.h"
+#  include "MediaCodecsSupport.h"
+#  include "MediaEventSource.h"
+#  include "MediaInfo.h"
+#  include "MediaResult.h"
+#  include "mozilla/EnumSet.h"
+#  include "mozilla/EnumTypeTraits.h"
+#  include "mozilla/MozPromise.h"
+#  include "mozilla/RefPtr.h"
+#  include "mozilla/TaskQueue.h"
+#  include "mozilla/layers/KnowsCompositor.h"
+#  include "mozilla/layers/LayersTypes.h"
+#  include "mozilla/ipc/UtilityAudioDecoder.h"
+#  include "nsTArray.h"
+#  include "PerformanceRecorder.h"
+
+namespace mozilla {
+class TrackInfo;
+class AudioInfo;
+class VideoInfo;
+class MediaRawData;
+class DecoderDoctorDiagnostics;
+
+namespace layers {
+class ImageContainer;
+}  // namespace layers
+
+class MediaDataDecoder;
+class RemoteDecoderModule;
+class CDMProxy;
+
+static LazyLogModule sPDMLog("PlatformDecoderModule");
+
+namespace media {
+
+enum class Option {
+  Default,
+  LowLatency,
+  HardwareDecoderNotAllowed,
+  FullH264Parsing,
+  ErrorIfNoInitializationData,  // By default frames delivered before
+                                // initialization data are dropped. Pass this
+                                // option to raise an error if frames are
+                                // delivered before initialization data.
+  DefaultPlaybackDeviceMono,    // Currently only used by Opus on RDD to avoid
+                                // initialization of audio backends on RDD
+
+  SENTINEL  // one past the last valid value
+};
+using OptionSet = EnumSet<Option>;
+
+struct UseNullDecoder {
+  UseNullDecoder() = default;
+  explicit UseNullDecoder(bool aUseNullDecoder) : mUse(aUseNullDecoder) {}
+  bool mUse = false;
+};
+
+// Do not wrap H264 decoder in a H264Converter.
+struct NoWrapper {
+  NoWrapper() = default;
+  explicit NoWrapper(bool aDontUseWrapper) : mDontUseWrapper(aDontUseWrapper) {}
+  bool mDontUseWrapper = false;
+};
+
+struct VideoFrameRate {
+  VideoFrameRate() = default;
+  explicit VideoFrameRate(float aFramerate) : mValue(aFramerate) {}
+  float mValue = 0.0f;
+};
+
+}  // namespace media
+
+struct CreateDecoderParams;
+struct CreateDecoderParamsForAsync {
+  using Option = media::Option;
+  using OptionSet = media::OptionSet;
+  explicit CreateDecoderParamsForAsync(const CreateDecoderParams& aParams);
+  CreateDecoderParamsForAsync(CreateDecoderParamsForAsync&& aParams);
+
+  const VideoInfo& VideoConfig() const {
+    MOZ_ASSERT(mConfig->IsVideo());
+    return *mConfig->GetAsVideoInfo();
+  }
+
+  const AudioInfo& AudioConfig() const {
+    MOZ_ASSERT(mConfig->IsAudio());
+    return *mConfig->GetAsAudioInfo();
+  }
+
+  UniquePtr<TrackInfo> mConfig;
+  const RefPtr<layers::ImageContainer> mImageContainer;
+  const RefPtr<layers::KnowsCompositor> mKnowsCompositor;
+  const RefPtr<GMPCrashHelper> mCrashHelper;
+  const media::UseNullDecoder mUseNullDecoder;
+  const media::NoWrapper mNoWrapper;
+  const TrackInfo::TrackType mType = TrackInfo::kUndefinedTrack;
+  std::function<MediaEventProducer<TrackInfo::TrackType>*()>
+      mOnWaitingForKeyEvent;
+  const OptionSet mOptions = OptionSet(Option::Default);
+  const media::VideoFrameRate mRate;
+  const Maybe<uint64_t> mMediaEngineId;
+  const Maybe<TrackingId> mTrackingId;
+};
+
+struct MOZ_STACK_CLASS CreateDecoderParams final {
+  using Option = media::Option;
+  using OptionSet = media::OptionSet;
+  using UseNullDecoder = media::UseNullDecoder;
+  using NoWrapper = media::NoWrapper;
+  using VideoFrameRate = media::VideoFrameRate;
+
+  explicit CreateDecoderParams(const TrackInfo& aConfig) : mConfig(aConfig) {}
+  CreateDecoderParams(const CreateDecoderParams& aParams) = default;
+
+  MOZ_IMPLICIT CreateDecoderParams(const CreateDecoderParamsForAsync& aParams)
+      : mConfig(*aParams.mConfig.get()),
+        mImageContainer(aParams.mImageContainer),
+        mKnowsCompositor(aParams.mKnowsCompositor),
+        mCrashHelper(aParams.mCrashHelper),
+        mUseNullDecoder(aParams.mUseNullDecoder),
+        mNoWrapper(aParams.mNoWrapper),
+        mType(aParams.mType),
+        mOnWaitingForKeyEvent(aParams.mOnWaitingForKeyEvent),
+        mOptions(aParams.mOptions),
+        mRate(aParams.mRate),
+        mMediaEngineId(aParams.mMediaEngineId),
+        mTrackingId(aParams.mTrackingId) {}
+
+  template <typename T1, typename... Ts>
+  CreateDecoderParams(const TrackInfo& aConfig, T1&& a1, Ts&&... args)
+      : mConfig(aConfig) {
+    Set(std::forward<T1>(a1), std::forward<Ts>(args)...);
+  }
+
+  template <typename T1, typename... Ts>
+  CreateDecoderParams(const CreateDecoderParams& aParams, T1&& a1, Ts&&... args)
+      : CreateDecoderParams(aParams) {
+    Set(std::forward<T1>(a1), std::forward<Ts>(args)...);
+  }
+
+  const VideoInfo& VideoConfig() const {
+    MOZ_ASSERT(mConfig.IsVideo());
+    return *mConfig.GetAsVideoInfo();
+  }
+
+  const AudioInfo& AudioConfig() const {
+    MOZ_ASSERT(mConfig.IsAudio());
+    return *mConfig.GetAsAudioInfo();
+  }
+
+  layers::LayersBackend GetLayersBackend() const {
+    if (mKnowsCompositor) {
+      return mKnowsCompositor->GetCompositorBackendType();
+    }
+    return layers::LayersBackend::LAYERS_NONE;
+  }
+
+  // CreateDecoderParams is a MOZ_STACK_CLASS, it is only used to
+  // simplify the passing of arguments to Create*Decoder.
+  // It is safe to use references and raw pointers.
+  const TrackInfo& mConfig;
+  layers::ImageContainer* mImageContainer = nullptr;
+  MediaResult* mError = nullptr;
+  layers::KnowsCompositor* mKnowsCompositor = nullptr;
+  GMPCrashHelper* mCrashHelper = nullptr;
+  media::UseNullDecoder mUseNullDecoder;
+  media::NoWrapper mNoWrapper;
+  TrackInfo::TrackType mType = TrackInfo::kUndefinedTrack;
+  std::function<MediaEventProducer<TrackInfo::TrackType>*()>
+      mOnWaitingForKeyEvent;
+  OptionSet mOptions = OptionSet(Option::Default);
+  media::VideoFrameRate mRate;
+  // Used on Windows when the MF media engine playback is enabled.
+  Maybe<uint64_t> mMediaEngineId;
+  Maybe<TrackingId> mTrackingId;
+
+ private:
+  void Set(layers::ImageContainer* aImageContainer) {
+    mImageContainer = aImageContainer;
+  }
+  void Set(MediaResult* aError) { mError = aError; }
+  void Set(GMPCrashHelper* aCrashHelper) { mCrashHelper = aCrashHelper; }
+  void Set(UseNullDecoder aUseNullDecoder) {
+    mUseNullDecoder = aUseNullDecoder;
+  }
+  void Set(NoWrapper aNoWrapper) { mNoWrapper = aNoWrapper; }
+  void Set(OptionSet aOptions) { mOptions = aOptions; }
+  void Set(VideoFrameRate aRate) { mRate = aRate; }
+  void Set(layers::KnowsCompositor* aKnowsCompositor) {
+    if (aKnowsCompositor) {
+      mKnowsCompositor = aKnowsCompositor;
+      MOZ_ASSERT(aKnowsCompositor->IsThreadSafe());
+    }
+  }
+  void Set(TrackInfo::TrackType aType) { mType = aType; }
+  void Set(std::function<MediaEventProducer<TrackInfo::TrackType>*()>&&
+               aOnWaitingForKey) {
+    mOnWaitingForKeyEvent = std::move(aOnWaitingForKey);
+  }
+  void Set(const std::function<MediaEventProducer<TrackInfo::TrackType>*()>&
+               aOnWaitingForKey) {
+    mOnWaitingForKeyEvent = aOnWaitingForKey;
+  }
+  void Set(const Maybe<uint64_t>& aMediaEngineId) {
+    mMediaEngineId = aMediaEngineId;
+  }
+  void Set(const Maybe<TrackingId>& aTrackingId) { mTrackingId = aTrackingId; }
+  void Set(const CreateDecoderParams& aParams) {
+    // Set all but mTrackInfo;
+    mImageContainer = aParams.mImageContainer;
+    mError = aParams.mError;
+    mKnowsCompositor = aParams.mKnowsCompositor;
+    mCrashHelper = aParams.mCrashHelper;
+    mUseNullDecoder = aParams.mUseNullDecoder;
+    mNoWrapper = aParams.mNoWrapper;
+    mType = aParams.mType;
+    mOnWaitingForKeyEvent = aParams.mOnWaitingForKeyEvent;
+    mOptions = aParams.mOptions;
+    mRate = aParams.mRate;
+    mMediaEngineId = aParams.mMediaEngineId;
+    mTrackingId = aParams.mTrackingId;
+  }
+  template <typename T1, typename T2, typename... Ts>
+  void Set(T1&& a1, T2&& a2, Ts&&... args) {
+    Set(std::forward<T1>(a1));
+    Set(std::forward<T2>(a2), std::forward<Ts>(args)...);
+  }
+};
+
+struct MOZ_STACK_CLASS SupportDecoderParams final {
+  using Option = media::Option;
+  using OptionSet = media::OptionSet;
+  using UseNullDecoder = media::UseNullDecoder;
+  using NoWrapper = media::NoWrapper;
+  using VideoFrameRate = media::VideoFrameRate;
+
+  explicit SupportDecoderParams(const TrackInfo& aConfig) : mConfig(aConfig) {}
+
+  explicit SupportDecoderParams(const CreateDecoderParams& aParams)
+      : mConfig(aParams.mConfig),
+        mError(aParams.mError),
+        mKnowsCompositor(aParams.mKnowsCompositor),
+        mUseNullDecoder(aParams.mUseNullDecoder),
+        mNoWrapper(aParams.mNoWrapper),
+        mOptions(aParams.mOptions),
+        mRate(aParams.mRate),
+        mMediaEngineId(aParams.mMediaEngineId) {}
+
+  template <typename T1, typename... Ts>
+  SupportDecoderParams(const TrackInfo& aConfig, T1&& a1, Ts&&... args)
+      : mConfig(aConfig) {
+    Set(std::forward<T1>(a1), std::forward<Ts>(args)...);
+  }
+
+  const nsCString& MimeType() const { return mConfig.mMimeType; }
+
+  const TrackInfo& mConfig;
+  DecoderDoctorDiagnostics* mDiagnostics = nullptr;
+  MediaResult* mError = nullptr;
+  RefPtr<layers::KnowsCompositor> mKnowsCompositor;
+  UseNullDecoder mUseNullDecoder;
+  NoWrapper mNoWrapper;
+  OptionSet mOptions = OptionSet(Option::Default);
+  VideoFrameRate mRate;
+  Maybe<uint64_t> mMediaEngineId;
+
+ private:
+  void Set(DecoderDoctorDiagnostics* aDiagnostics) {
+    mDiagnostics = aDiagnostics;
+  }
+  void Set(MediaResult* aError) { mError = aError; }
+  void Set(media::UseNullDecoder aUseNullDecoder) {
+    mUseNullDecoder = aUseNullDecoder;
+  }
+  void Set(media::NoWrapper aNoWrapper) { mNoWrapper = aNoWrapper; }
+  void Set(media::OptionSet aOptions) { mOptions = aOptions; }
+  void Set(media::VideoFrameRate aRate) { mRate = aRate; }
+  void Set(layers::KnowsCompositor* aKnowsCompositor) {
+    if (aKnowsCompositor) {
+      mKnowsCompositor = aKnowsCompositor;
+      MOZ_ASSERT(aKnowsCompositor->IsThreadSafe());
+    }
+  }
+  void Set(const Maybe<uint64_t>& aMediaEngineId) {
+    mMediaEngineId = aMediaEngineId;
+  }
+
+  template <typename T1, typename T2, typename... Ts>
+  void Set(T1&& a1, T2&& a2, Ts&&... args) {
+    Set(std::forward<T1>(a1));
+    Set(std::forward<T2>(a2), std::forward<Ts>(args)...);
+  }
+};
+
+// Used for IPDL serialization.
+// The 'value' have to be the biggest enum from CreateDecoderParams::Option.
+template <>
+struct MaxEnumValue<::mozilla::CreateDecoderParams::Option> {
+  static constexpr unsigned int value =
+      static_cast<unsigned int>(CreateDecoderParams::Option::SENTINEL);
+};
+
+// The PlatformDecoderModule interface is used by the MediaFormatReader to
+// abstract access to decoders provided by various
+// platforms.
+// Each platform (Windows, MacOSX, Linux, B2G etc) must implement a
+// PlatformDecoderModule to provide access to its decoders in order to get
+// decompressed H.264/AAC from the MediaFormatReader.
+//
+// Decoding is asynchronous, and should be performed on the task queue
+// provided if the underlying platform isn't already exposing an async API.
+//
+// A cross-platform decoder module that discards input and produces "blank"
+// output samples exists for testing, and is created when the pref
+// "media.use-blank-decoder" is true.
+
+class PlatformDecoderModule {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(PlatformDecoderModule)
+
+  // Perform any per-instance initialization.
+  // This is called on the decode task queue.
+  virtual nsresult Startup() { return NS_OK; }
+
+  // Indicates if the PlatformDecoderModule supports decoding of aMimeType,
+  // and whether or not hardware-accelerated decoding is supported.
+  // The answer to both SupportsMimeType and Supports doesn't guarantee that
+  // creation of a decoder will actually succeed.
+  virtual media::DecodeSupportSet SupportsMimeType(
+      const nsACString& aMimeType,
+      DecoderDoctorDiagnostics* aDiagnostics) const = 0;
+
+  virtual media::DecodeSupportSet Supports(
+      const SupportDecoderParams& aParams,
+      DecoderDoctorDiagnostics* aDiagnostics) const {
+    const TrackInfo& trackInfo = aParams.mConfig;
+    const media::DecodeSupportSet support =
+        SupportsMimeType(trackInfo.mMimeType, aDiagnostics);
+
+    // Bail early if we don't support this format at all
+    if (support == media::DecodeSupport::Unsupported) {
+      return support;
+    }
+
+    const auto* videoInfo = trackInfo.GetAsVideoInfo();
+
+    if (!videoInfo) {
+      // No video stream = software decode only
+      return media::DecodeSupport::SoftwareDecode;
+    }
+
+    // Check whether we support the desired color depth
+    if (!SupportsColorDepth(videoInfo->mColorDepth, aDiagnostics)) {
+      return media::DecodeSupport::Unsupported;
+    }
+    return support;
+  }
+
+  using CreateDecoderPromise = MozPromise<RefPtr<MediaDataDecoder>, MediaResult,
+                                          /* IsExclusive = */ true>;
+
+ protected:
+  PlatformDecoderModule() = default;
+  virtual ~PlatformDecoderModule() = default;
+
+  friend class MediaChangeMonitor;
+  friend class PDMFactory;
+  friend class EMEDecoderModule;
+  friend class RemoteDecoderModule;
+
+  // Indicates if the PlatformDecoderModule supports decoding of aColorDepth.
+  // Should override this method when the platform can support color depth != 8.
+  virtual bool SupportsColorDepth(
+      gfx::ColorDepth aColorDepth,
+      DecoderDoctorDiagnostics* aDiagnostics) const {
+    return aColorDepth == gfx::ColorDepth::COLOR_8;
+  }
+
+  // Creates a Video decoder. The layers backend is passed in so that
+  // decoders can determine whether hardware accelerated decoding can be used.
+  // On Windows the task queue's threads in have MSCOM initialized with
+  // COINIT_MULTITHREADED.
+  // Returns nullptr if the decoder can't be created.
+  // It is not safe to store a reference to aParams or aParams.mConfig as the
+  // object isn't guaranteed to live after the call.
+  // CreateVideoDecoder may need to make additional checks if the
+  // CreateDecoderParams argument is actually supported and return nullptr if
+  // not to allow for fallback PDMs to be tried.
+  virtual already_AddRefed<MediaDataDecoder> CreateVideoDecoder(
+      const CreateDecoderParams& aParams) = 0;
+
+  // Creates an Audio decoder with the specified properties.
+  // Returns nullptr if the decoder can't be created.
+  // On Windows the task queue's threads in have MSCOM initialized with
+  // COINIT_MULTITHREADED.
+  // It is not safe to store a reference to aParams or aParams.mConfig as the
+  // object isn't guaranteed to live after the call.
+  // CreateAudioDecoder may need to make additional checks if the
+  // CreateDecoderParams argument is actually supported and return nullptr if
+  // not to allow for fallback PDMs to be tried.
+  virtual already_AddRefed<MediaDataDecoder> CreateAudioDecoder(
+      const CreateDecoderParams& aParams) = 0;
+
+  // Asychronously create a decoder.
+  virtual RefPtr<CreateDecoderPromise> AsyncCreateDecoder(
+      const CreateDecoderParams& aParams);
+};
+
+DDLoggedTypeDeclName(MediaDataDecoder);
+
+// MediaDataDecoder is the interface exposed by decoders created by the
+// PlatformDecoderModule's Create*Decoder() functions. The type of
+// media data that the decoder accepts as valid input and produces as
+// output is determined when the MediaDataDecoder is created.
+//
+// Unless otherwise noted, all functions are only called on the decode task
+// queue.  An exception is the MediaDataDecoder in
+// MediaFormatReader::IsVideoAccelerated() for which all calls (Init(),
+// IsHardwareAccelerated(), and Shutdown()) are from the main thread.
+//
+// Don't block inside these functions, unless it's explicitly noted that you
+// should (like in Flush()).
+//
+// Decoding is done asynchronously.
+class MediaDataDecoder : public DecoderDoctorLifeLogger<MediaDataDecoder> {
+ protected:
+  virtual ~MediaDataDecoder() = default;
+
+ public:
+  typedef TrackInfo::TrackType TrackType;
+  typedef nsTArray<RefPtr<MediaData>> DecodedData;
+  typedef MozPromise<TrackType, MediaResult, /* IsExclusive = */ true>
+      InitPromise;
+  typedef MozPromise<DecodedData, MediaResult, /* IsExclusive = */ true>
+      DecodePromise;
+  typedef MozPromise<bool, MediaResult, /* IsExclusive = */ true> FlushPromise;
+
+  NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
+
+  // Initialize the decoder. The decoder should be ready to decode once
+  // the promise resolves. The decoder should do any initialization here, rather
+  // than in its constructor or PlatformDecoderModule::Create*Decoder(),
+  // so that if the MediaFormatReader needs to shutdown during initialization,
+  // it can call Shutdown() to cancel this operation. Any initialization
+  // that requires blocking the calling thread in this function *must*
+  // be done here so that it can be canceled by calling Shutdown()!
+  // Methods Decode, DecodeBatch, Drain, Flush, Shutdown are guaranteed to be
+  // called on the thread where Init() first ran.
+  virtual RefPtr<InitPromise> Init() = 0;
+
+  // Inserts a sample into the decoder's decode pipeline. The DecodePromise will
+  // be resolved with the decoded MediaData. In case the decoder needs more
+  // input, the DecodePromise may be resolved with an empty array of samples to
+  // indicate that Decode should be called again before a MediaData is returned.
+  virtual RefPtr<DecodePromise> Decode(MediaRawData* aSample) = 0;
+
+  // This could probably be implemented as a wrapper that takes a
+  // generic MediaDataDecoder and manages batching as needed.  For now
+  // only AudioTrimmer with RemoteMediaDataDecoder supports batch
+  // decoding.
+  // Inserts an array of samples into the decoder's decode pipeline. The
+  // DecodePromise will be resolved with the decoded MediaData. In case
+  // the decoder needs more input, the DecodePromise may be resolved
+  // with an empty array of samples to indicate that Decode should be
+  // called again before a MediaData is returned.
+  virtual bool CanDecodeBatch() const { return false; }
+  virtual RefPtr<DecodePromise> DecodeBatch(
+      nsTArray<RefPtr<MediaRawData>>&& aSamples) {
+    MOZ_CRASH("DecodeBatch not implemented yet");
+    return MediaDataDecoder::DecodePromise::CreateAndReject(
+        NS_ERROR_DOM_MEDIA_DECODE_ERR, __func__);
+  }
+
+  // Causes all complete samples in the pipeline that can be decoded to be
+  // output. If the decoder can't produce samples from the current output,
+  // it drops the input samples. The decoder may be holding onto samples
+  // that are required to decode samples that it expects to get in future.
+  // This is called when the demuxer reaches end of stream.
+  // This function is asynchronous.
+  // The MediaDataDecoder shall resolve the pending DecodePromise with drained
+  // samples. Drain will be called multiple times until the resolved
+  // DecodePromise is empty which indicates that there are no more samples to
+  // drain.
+  virtual RefPtr<DecodePromise> Drain() = 0;
+
+  // Causes all samples in the decoding pipeline to be discarded. When this
+  // promise resolves, the decoder must be ready to accept new data for
+  // decoding. This function is called when the demuxer seeks, before decoding
+  // resumes after the seek. The current DecodePromise if any shall be rejected
+  // with NS_ERROR_DOM_MEDIA_CANCELED
+  virtual RefPtr<FlushPromise> Flush() = 0;
+
+  // Cancels all init/decode/drain operations, and shuts down the decoder. The
+  // platform decoder should clean up any resources it's using and release
+  // memory etc. The shutdown promise will be resolved once the decoder has
+  // completed shutdown. The reader calls Flush() before calling Shutdown(). The
+  // reader will delete the decoder once the promise is resolved.
+  // The ShutdownPromise must only ever be resolved.
+  // Shutdown() may not be called if init hasn't been called first. It is
+  // possible under some circumstances for the decoder to be deleted without
+  // Init having been called first.
+  virtual RefPtr<ShutdownPromise> Shutdown() = 0;
+
+  // Called from the state machine task queue or main thread. Decoder needs to
+  // decide whether or not hardware acceleration is supported after creating.
+  // It doesn't need to call Init() before calling this function.
+  virtual bool IsHardwareAccelerated(nsACString& aFailureReason) const {
+    return false;
+  }
+
+  // Return the name of the MediaDataDecoder, only used for decoding.
+  // May be accessed in a non thread-safe fashion.
+  virtual nsCString GetDescriptionName() const = 0;
+
+  virtual nsCString GetProcessName() const {
+    nsCString rv = nsCString(XRE_GetProcessTypeString());
+    if (XRE_IsUtilityProcess()) {
+      rv += "+"_ns + mozilla::ipc::GetChildAudioActorName();
+    }
+    return rv;
+  };
+  virtual nsCString GetCodecName() const = 0;
+
+  // Set a hint of seek target time to decoder. Decoder will drop any decoded
+  // data which pts is smaller than this value. This threshold needs to be clear
+  // after reset decoder. To clear it explicitly, call this method with
+  // TimeUnit::Invalid().
+  // Decoder may not honor this value. However, it'd be better that
+  // video decoder implements this API to improve seek performance.
+  // Note: it should be called before Input() or after Flush().
+  virtual void SetSeekThreshold(const media::TimeUnit& aTime) {}
+
+  // When playing adaptive playback, recreating an Android video decoder will
+  // cause the transition not smooth during resolution change.
+  // Reuse the decoder if the decoder support recycling.
+  // Currently, only Android video decoder will return true.
+  virtual bool SupportDecoderRecycling() const { return false; }
+
+  enum class ConversionRequired {
+    kNeedNone = 0,
+    kNeedAVCC = 1,
+    kNeedAnnexB = 2,
+  };
+
+  // Indicates that the decoder requires a specific format.
+  // The demuxed data will be converted accordingly before feeding it to
+  // Decode().
+  virtual ConversionRequired NeedsConversion() const {
+    return ConversionRequired::kNeedNone;
+  }
+};
+
+}  // namespace mozilla
+
+#endif