Interfaces for encoded video sources

content/common/media/encoded_video_source_messages.h

+// Copyright 2013 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.
+
+#include "base/shared_memory.h"
+#include "content/common/content_export.h"
+#include "ipc/ipc_message_macros.h"
+#include "ipc/ipc_message_start.h"
+#include "media/video/encoded_video_source.h"
+#include "media/video/video_encode_types.h"
+
+#undef IPC_MESSAGE_EXPORT
+#define IPC_MESSAGE_EXPORT CONTENT_EXPORT
+#define IPC_MESSAGE_START EncodedVideoSourceMsgStart
+
+IPC_ENUM_TRAITS(media::VideoCodec)
+
+IPC_ENUM_TRAITS(media::EncodedVideoBitstream::DestructionReason)
+
+IPC_STRUCT_TRAITS_BEGIN(media::TemporalLayerParameters)
+  IPC_STRUCT_TRAITS_MEMBER(enabled)
+  IPC_STRUCT_TRAITS_MEMBER(target_bitrate)
+IPC_STRUCT_TRAITS_END()
+
+IPC_STRUCT_TRAITS_BEGIN(media::RuntimeVideoEncodingParameters)
+  IPC_STRUCT_TRAITS_MEMBER(frames_per_second)
+  IPC_STRUCT_TRAITS_MEMBER(max_bitrate)
+  IPC_STRUCT_TRAITS_MEMBER(max_qp)
+  IPC_STRUCT_TRAITS_MEMBER(temporal_layer_params)
+IPC_STRUCT_TRAITS_END()
+
+IPC_STRUCT_TRAITS_BEGIN(media::VideoEncodingParameters)
+  IPC_STRUCT_TRAITS_MEMBER(profile)
+  IPC_STRUCT_TRAITS_MEMBER(resolution)
+  IPC_STRUCT_TRAITS_MEMBER(runtime_params)
+IPC_STRUCT_TRAITS_END()
+
+IPC_STRUCT_TRAITS_BEGIN(media::BufferEncodingMetadata)
+  IPC_STRUCT_TRAITS_MEMBER(timestamp)
+  IPC_STRUCT_TRAITS_MEMBER(frame_type_flags)
+  IPC_STRUCT_TRAITS_MEMBER(temporal_layer_id)
+  IPC_STRUCT_TRAITS_MEMBER(layer_sync)
+  IPC_STRUCT_TRAITS_MEMBER(droppable)
+IPC_STRUCT_TRAITS_END()
+
+// Need to typedef BitstreamBufferMap in order to prevent the IPC message macros
+// from choking on the comma.
+typedef std::map<int, base::SharedMemoryHandle> BitstreamBufferMap;
+
+// Message from Renderer to Browser process to create a bitstream with specific
+// parameters. A successful request results in beginning of streaming and
+// EncoderVideoSourceMsg_BitstreamCreated message to Renderer. A failed request
+// triggers EncodedVideoSourceMsg_BitstreamDestroyed message. As this set of
+// messages is designed to work with existing device, device_id is determined
+// on the basis which device is providing the encoded video source
+// functionality. Renderer is responsible for generating unique stream_id within
+// its context that will be used to identify bitstreams in IPC.
+IPC_MESSAGE_CONTROL3(EncodedVideoSourceHostMsg_CreateBitstream,
+                     int /* device_id */,
+                     int /* stream_id */,
+                     media::VideoEncodingParameters /* params */)
+
+// Message from Renderer to Browser process to tell that the data within a
+// buffer has been processed and it can be reused to encode upcoming bitstream.
+IPC_MESSAGE_CONTROL3(EncodedVideoSourceHostMsg_BitstreamBufferConsumed,
+                     int /* device_id */,
+                     int /* stream_id */,
+                     int /* buffer_id */)
+
+// Message from Renderer to Browser process to stop streaming a bitstream. When
+// Browser has finalized the bitstream it will trigger
+// EncodedVideoSourceMsg_BitstreamDestroyed message back from Browser to
+// Renderer. Renderer must be prepared to receive
+// EncodedVideoSourceMsg_BitstreamReady messages until it has received the
+// EncodedVideoSourceMsg_BitstreamDestroyed message.
+IPC_MESSAGE_CONTROL2(EncodedVideoSourceHostMsg_DestroyBitstream,
+                     int /* device_id */,
+                     int /* stream_id */)
+
+// Message from Renderer to Browser process to set a stream's bitstream config.
+// Will always result in EncodedVideoSourceMsg_BitstreamConfigChanged containing
+// currently active parameters, regardless of whether this call succeeded or
+// not.
+IPC_MESSAGE_CONTROL3(EncodedVideoSourceHostMsg_TryConfigureBitstream,
+                     int /* device_id */,
+                     int /* stream_id */,
+                     media::RuntimeVideoEncodingParameters /* params */)
+
+// Message from Renderer to Browser process to request special frames from the
+// encoded video source. There will be no acknowledgement for this request and
+// the effect is only visible in the bitstream buffers passed to client
+// through the EncodedVideoSourceMsg_BitstreamReady message. This request is
+// served on a best-effort basis and client is not given any guarantees of the
+// realization or timing of the request. Flags parameter will be interpreted in
+// codec-specific manner using enumerations.
+IPC_MESSAGE_CONTROL3(EncodedVideoSourceHostMsg_RequestSpecialFrame,
+                     int /* device_id */,
+                     int /* stream_id */,
+                     int /* flags */)
+
+// Message from Browser to Renderer process to acknowledge a request to create
+// an encoded video bitstream. When this message occurs bitstream can be
+// considered to be streaming and Renderer should be ready to start accepting
+// EncodedVideoSourceMsg_BitstreamReady messages and buffers contained within
+// them. Shared memory buffers used to deliver the bitstream are assigned with
+// buffer ids as specified by the buffers parameter.
+IPC_MESSAGE_CONTROL4(EncodedVideoSourceMsg_BitstreamCreated,
+                     int /* device id */,
+                     int /* stream id */,
+                     media::VideoEncodingParameters /* params */,
+                     BitstreamBufferMap /* buffers */)
+
+// Message from Browser to Renderer process to acknowledge a request to destroy
+// an encoded video bitstream. Also used to signal renderer process that an
+// unrecoverable error has occurred and as a result bitstream has been
+// destroyed.
+IPC_MESSAGE_CONTROL3(EncodedVideoSourceMsg_BitstreamDestroyed,
+                     int /* device id */,
+                     int /* stream id */,
+                     media::EncodedVideoBitstream::DestructionReason /* rslt */)
+
+// Message from Browser to Renderer process to inform the clients of the current
+// encoding parameters, regardless of whether the previous request to change
+// them has been successful or not. This is called usually as a response to
+// EncodedVideoSourceHostMsg_TryConfigureBitstream during runtime, but can occur
+// also as a result of config change initiated by encoder or other clients in
+// the system. E.g. if there are multiple clients and bitstream config change is
+// requested from one client, all clients should be prepared to handle the
+// configuration change.
+IPC_MESSAGE_CONTROL3(EncodedVideoSourceMsg_BitstreamConfigChanged,
+                     int /* device id */,
+                     int /* stream id */,
+                     media::RuntimeVideoEncodingParameters /* current_params */)
+
+// Message from Browser to Renderer process indicating that a bitstream buffer
+// is available for the stream.
+IPC_MESSAGE_CONTROL4(EncodedVideoSourceMsg_BitstreamReady,
+                     int /* device id */,
+                     int /* stream_id */,
+                     int /* buffer_id */,
+                     media::BufferEncodingMetadata /* metadata */)
+