media::mojom::Remoter and CastRemotingConnector/Sender

media/mojo/interfaces/remoter.mojom

+// Copyright 2016 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.
+
+module media.mojom;
+
+import "media/mojo/interfaces/media_types.mojom";
+
+// An HTML5 media element supports a canPlayType() query. This structure
+// represents a "matcher" for a set of possible container+codec pairs.
+struct RemotePlayType {
+  // The base type (i.e., no extra parameters).
+  string mime_type;  // (e.g., 'video/webm')
+
+  // List of regular expressions that each match one or more codecs. For
+  // example, to represent that both VP8 and VP9 are supported, one entry
+  // would be 'vp[89]'.
+  array<string> supported_codecs;
+  array<string> ambiguously_supported_codecs;
+};
+
+// Inner structure used in the RemoteKeySystem struct.
+struct RemoteContentCapability {
+  RemotePlayType play_type;
+  string robustness;  // Defined by key system scheme.
+};
+
+// A MediaKeySystemConfiguration (see EME W3C spec) supported by the remote
+// media services.
+struct RemoteKeySystem {
+  string name;  // Reverse URI (e.g., "org.w3.clearkey")
+  array<string> init_data_types;
+  array<RemoteContentCapability> audio_capabilities;
+  array<RemoteContentCapability> video_capabilities;
+  enum Requirement { REQUIRED, OPTIONAL, NOT_ALLOWED };
+  Requirement distinctive_identifier;
+  Requirement persistent_state;
+  array<string> session_types;
+};
+
+// Structure describing the capabilities of the remote media services.
+struct RemoteCapabilities {
+  // List of RemotePlayTypes evaluated against canPlayType() queries to
+  // determine whether the remote supports playback of a specific format/codec
+  // of content (when not using an DRM key system).
+  array<RemotePlayType> play_types;
+
+  // List of supported DRM key system configurations.
+  array<RemoteKeySystem> key_systems;
+};
+
+interface Remoter {
+  // Register the client that is to be notified when remote media services are
+  // available/gone, and for session-level lifecycle events.
+  RegisterClient(RemoterClient client);
+
+  // Called to start remote media services. If |success| is true in the result,
+  // calls to SendMessageToRemote() and SendBufferToRemote() can be made, and
+  // any messages from the remote will be forwarded back to the client via
+  // RemoterClient.OnMessageFromRemote().
+  //
+  // |audio_pipe| and |video_pipe| provide handles to the consumer end of a data
+  // pipe. These data pipes are used for the transport of the demuxed bitstream
+  // data. The Remoter is instructed to read from these pipes and send the
+  // bitstream data to the remote whenever SendBufferToRemote() is called.
+  StartMediaServices(handle<data_pipe_consumer>? audio_pipe,
+                     handle<data_pipe_consumer>? video_pipe) =>
+      (bool success, uint32 audio_pipe_id, uint32 video_pipe_id);
+
+  // Called to stop remote media services. Messages in both directions will be
+  // dropped after this point, and the consumer end of the data pipes passed to
+  // StartMediaServices() will be closed. If the optional |error_reason| is
+  // missing, this is a normal stop command; otherwise, |error_reason| contains
+  // a human-readable string indicating the failure(s) that forced remoting to
+  // be stopped.
+  StopMediaServices(string? error_reason);
+
+  // Forward |message| to the remote endpoint over an encrypted, reliable
+  // transport. |message| is a serialized protobuf from
+  // src/media/remoting/proto/...
+  SendMessageToRemote(array<uint8> message);
+
+  // Forward |buffer| to the remote endpoint over an encrypted, reliable
+  // transport. Before this is called, the client must write |buffer.data_size|
+  // bytes into one of the data pipes. |pipe_id| selects which data pipe will be
+  // read from (audio or video).
+  SendBufferToRemote(uint32 pipe_id, DecoderBuffer buffer);
+};
+
+interface RemoterClient {
+  // Called to notify the client that remote media services are now available,
+  // along with some information about their capabilities to help the client
+  // decide whether/when to begin remoting (with sufficient support). When the
+  // client is ready to start remoting media, it calls
+  // Remoter.StartMediaServices().
+  OnRemoteServicesAvailable(RemoteCapabilities capabilities);
+
+  // Called to notify the client the remote media services are no longer
+  // available. Note that this is different from OnMediaServicesStopped() in
+  // that it does not indicate active remoting of media services has been
+  // stopped.
+  OnRemoteServicesGone();
+
+  // Called while remoting is active to pass a |message| from the remote media
+  // services to the local media stack. The |message| is guaranteed to have been
+  // received over an encrypted, reliable transport and consists of a serialized
+  // protobuf from src/media/remoting/proto/...
+  OnMessageFromRemote(array<uint8> message);
+
+  // Called when remote media services have terminated. This may or may not be a
+  // response to a Remoter::StopMediaServices() call, as external causes may be
+  // the reason remoting was ended. If |error_reason| is present, this indicates
+  // remoting was ended due to a fatal error and the string provides a
+  // human-readable reason message.
+  OnMediaServicesStopped(string? error_reason);
+};