Pepper: PPB_VideoEncoder implementation

ppapi/proxy/video_encoder_resource.cc

 // Copyright 2015 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/memory/shared_memory.h"
+#include "ppapi/c/pp_array_output.h"
+#include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/proxy/video_encoder_resource.h"
+#include "ppapi/proxy/video_frame_resource.h"
+#include "ppapi/shared_impl/media_stream_buffer.h"
+#include "ppapi/shared_impl/media_stream_buffer_manager.h"
+#include "ppapi/thunk/enter.h"
 
+using ppapi::proxy::SerializedHandle;
+using ppapi::thunk::EnterResourceNoLock;
 using ppapi::thunk::PPB_VideoEncoder_API;
 
 namespace ppapi {
 namespace proxy {
 
+namespace {
+
+void RunCallback(scoped_refptr<TrackedCallback>* callback, int32_t error) {
+  if (!TrackedCallback::IsPending(*callback))
+    return;
+
+  scoped_refptr<TrackedCallback> temp;
+  callback->swap(temp);
+  temp->Run(error);
+}
+
+}  // namespace
+
+VideoEncoderResource::ShmBuffer::ShmBuffer(uint32_t id,
+                                           scoped_ptr<base::SharedMemory> shm)
+    : id(id), shm(shm.Pass()) {
+}
+
+VideoEncoderResource::ShmBuffer::~ShmBuffer() {
+}
+
+VideoEncoderResource::BitstreamBuffer::BitstreamBuffer(uint32_t id,
+                                                       uint32_t size,
+                                                       bool key_frame)
+    : id(id), size(size), key_frame(key_frame) {
+}
+
+VideoEncoderResource::BitstreamBuffer::~BitstreamBuffer() {
+}
+
 VideoEncoderResource::VideoEncoderResource(Connection connection,
                                            PP_Instance instance)
-    : PluginResource(connection, instance) {
+    : PluginResource(connection, instance),
+      initialized_(false),
+      closed_(false),
+      // Set |encoder_last_error_| to PP_OK after successful initialization.
+      // This makes error checking a little more concise, since we can check
+      // that the encoder has been initialized and hasn't returned an error by
+      // just testing |encoder_last_error_|.
+      encoder_last_error_(PP_ERROR_FAILED),
+      input_frame_count_(0),
+      input_coded_size_(PP_MakeSize(0, 0)),
+      buffer_manager_(this),
+      get_video_frame_data_(nullptr),
+      get_bitstream_buffer_data_(nullptr) {
+  SendCreate(RENDERER, PpapiHostMsg_VideoEncoder_Create());
 }
 
 VideoEncoderResource::~VideoEncoderResource() {
+  Close();
 }
 
 PPB_VideoEncoder_API* VideoEncoderResource::AsPPB_VideoEncoder_API() {
   return this;
 }
 
 int32_t VideoEncoderResource::GetSupportedProfiles(
     const PP_ArrayOutput& output,
     const scoped_refptr<TrackedCallback>& callback) {
-  return PP_ERROR_FAILED;
+  if (TrackedCallback::IsPending(get_supported_profiles_callback_))
+    return PP_ERROR_INPROGRESS;
+
+  get_supported_profiles_callback_ = callback;
+  Call<PpapiPluginMsg_VideoEncoder_GetSupportedProfilesReply>(
+      RENDERER, PpapiHostMsg_VideoEncoder_GetSupportedProfiles(),
+      base::Bind(&VideoEncoderResource::OnPluginMsgGetSupportedProfilesReply,
+                 this, output));
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t VideoEncoderResource::GetFramesRequired() {
+  if (encoder_last_error_)
+    return encoder_last_error_;
+  return input_frame_count_;
+}
+
+int32_t VideoEncoderResource::GetFrameCodedSize(PP_Size* size) {
+  if (encoder_last_error_)
+    return encoder_last_error_;
+  *size = input_coded_size_;
+  return PP_OK;
 }
 
 int32_t VideoEncoderResource::Initialize(
     PP_VideoFrame_Format input_format,
     const PP_Size* input_visible_size,
     PP_VideoProfile output_profile,
     uint32_t initial_bitrate,
     PP_HardwareAcceleration acceleration,
     const scoped_refptr<TrackedCallback>& callback) {
-  return PP_ERROR_FAILED;
-}
-
-int32_t VideoEncoderResource::GetFramesRequired() {
-  return PP_ERROR_FAILED;
-}
-
-int32_t VideoEncoderResource::GetFrameCodedSize(PP_Size* size) {
-  return PP_ERROR_FAILED;
+  if (initialized_)
+    return PP_ERROR_FAILED;
+  if (TrackedCallback::IsPending(initialize_callback_))
+    return PP_ERROR_INPROGRESS;
+
+  initialize_callback_ = callback;
+  Call<PpapiPluginMsg_VideoEncoder_InitializeReply>(
+      RENDERER, PpapiHostMsg_VideoEncoder_Initialize(
+                    input_format, *input_visible_size, output_profile,
+                    initial_bitrate, acceleration),
+      base::Bind(&VideoEncoderResource::OnPluginMsgInitializeReply, this));
+  return PP_OK_COMPLETIONPENDING;
 }
 
 int32_t VideoEncoderResource::GetVideoFrame(
     PP_Resource* video_frame,
     const scoped_refptr<TrackedCallback>& callback) {
-  return PP_ERROR_FAILED;
+  if (encoder_last_error_)
+    return encoder_last_error_;
+
+  if (TrackedCallback::IsPending(get_video_frame_callback_))
+    return PP_ERROR_INPROGRESS;
+
+  get_video_frame_data_ = video_frame;
+  get_video_frame_callback_ = callback;
+
+  // Lazily ask for a shared memory buffer in which video frames are allocated.
+  if (buffer_manager_.number_of_buffers() == 0) {
+    Call<PpapiPluginMsg_VideoEncoder_GetVideoFramesReply>(
+        RENDERER, PpapiHostMsg_VideoEncoder_GetVideoFrames(),
+        base::Bind(&VideoEncoderResource::OnPluginMsgGetVideoFramesReply,
+                   this));
+  } else {
+    TryWriteVideoFrame();
+  }
+
+  return PP_OK_COMPLETIONPENDING;
 }
 
 int32_t VideoEncoderResource::Encode(
     PP_Resource video_frame,
     PP_Bool force_keyframe,
     const scoped_refptr<TrackedCallback>& callback) {
-  return PP_ERROR_FAILED;
+  if (encoder_last_error_)
+    return encoder_last_error_;
+
+  VideoFrameMap::iterator it = video_frames_.find(video_frame);
+  if (it == video_frames_.end())
+    // TODO(llandwerlin): accept MediaStreamVideoTrack's video frames.
+    return PP_ERROR_BADRESOURCE;
+
+  scoped_refptr<VideoFrameResource> frame_resource = it->second;
+
+  encode_callbacks_.push_back(callback);
+
+  Call<PpapiPluginMsg_VideoEncoder_EncodeReply>(
+      RENDERER,
+      PpapiHostMsg_VideoEncoder_Encode(frame_resource->GetBufferIndex(),
+                                       PP_ToBool(force_keyframe)),
+      base::Bind(&VideoEncoderResource::OnPluginMsgEncodeReply, this));
+
+  // Invalidate the frame to prevent the plugin from modifying it.
+  it->second->Invalidate();
+  video_frames_.erase(it);
+
+  return PP_OK_COMPLETIONPENDING;
 }
 
 int32_t VideoEncoderResource::GetBitstreamBuffer(
-    PP_BitstreamBuffer* picture,
+    PP_BitstreamBuffer* bitstream_buffer,
     const scoped_refptr<TrackedCallback>& callback) {
-  return PP_ERROR_FAILED;
+  if (encoder_last_error_)
+    return encoder_last_error_;
+  if (TrackedCallback::IsPending(get_bitstream_buffer_callback_))
+    return PP_ERROR_INPROGRESS;
+
+  get_bitstream_buffer_callback_ = callback;
+  get_bitstream_buffer_data_ = bitstream_buffer;
+
+  if (!available_bitstream_buffers_.empty()) {
+    BitstreamBuffer buffer(available_bitstream_buffers_.front());
+    available_bitstream_buffers_.pop_front();
+    WriteBitstreamBuffer(buffer);
+  }
+
+  return PP_OK_COMPLETIONPENDING;
 }
 
 void VideoEncoderResource::RecycleBitstreamBuffer(
-    const PP_BitstreamBuffer* picture) {
+    const PP_BitstreamBuffer* bitstream_buffer) {
+  if (encoder_last_error_)
+    return;
+  BitstreamBufferMap::const_iterator iter =
+      bitstream_buffer_map_.find(bitstream_buffer->buffer);
+  if (iter != bitstream_buffer_map_.end()) {
+    Post(RENDERER,
+         PpapiHostMsg_VideoEncoder_RecycleBitstreamBuffer(iter->second));
+  }
 }
 
 void VideoEncoderResource::RequestEncodingParametersChange(uint32_t bitrate,
                                                            uint32_t framerate) {
+  if (encoder_last_error_)
+    return;
+  Post(RENDERER, PpapiHostMsg_VideoEncoder_RequestEncodingParametersChange(
+                     bitrate, framerate));
 }
 
 void VideoEncoderResource::Close() {
+  if (closed_)
+    return;
+  Post(RENDERER, PpapiHostMsg_VideoEncoder_Close());
+  closed_ = true;
+  if (!encoder_last_error_ || !initialized_)
+    NotifyError(PP_ERROR_ABORTED);
+  ReleaseFrames();
+}
+
+void VideoEncoderResource::OnReplyReceived(
+    const ResourceMessageReplyParams& params,
+    const IPC::Message& msg) {
+  PPAPI_BEGIN_MESSAGE_MAP(VideoEncoderResource, msg)
+    PPAPI_DISPATCH_PLUGIN_RESOURCE_CALL(
+        PpapiPluginMsg_VideoEncoder_BitstreamBuffers,
+        OnPluginMsgBitstreamBuffers)
+    PPAPI_DISPATCH_PLUGIN_RESOURCE_CALL(
+        PpapiPluginMsg_VideoEncoder_BitstreamBufferReady,
+        OnPluginMsgBitstreamBufferReady)
+    PPAPI_DISPATCH_PLUGIN_RESOURCE_CALL(PpapiPluginMsg_VideoEncoder_NotifyError,
+                                        OnPluginMsgNotifyError)
+    PPAPI_DISPATCH_PLUGIN_RESOURCE_CALL_UNHANDLED(
+        PluginResource::OnReplyReceived(params, msg))
+  PPAPI_END_MESSAGE_MAP()
+}
+
+void VideoEncoderResource::OnPluginMsgGetSupportedProfilesReply(
+    const PP_ArrayOutput& output,
+    const ResourceMessageReplyParams& params,
+    const std::vector<PP_VideoProfileDescription>& profiles) {
+  void* ptr = output.GetDataBuffer(output.user_data, profiles.size(),
+                                   sizeof(PP_VideoProfileDescription));
+
+  if (!ptr) {
+    RunCallback(&get_supported_profiles_callback_, PP_ERROR_FAILED);
+    return;
+  }
+
+  if (profiles.size() > 0)
+    memcpy(ptr, &profiles[0],
+           profiles.size() * sizeof(PP_VideoProfileDescription));
+  RunCallback(&get_supported_profiles_callback_, PP_OK);
+}
+
+void VideoEncoderResource::OnPluginMsgInitializeReply(
+    const ResourceMessageReplyParams& params,
+    uint32_t input_frame_count,
+    const PP_Size& input_coded_size) {
+  DCHECK(!initialized_);
+
+  encoder_last_error_ = params.result();
+  if (!encoder_last_error_)
+    initialized_ = true;
+
+  input_frame_count_ = input_frame_count;
+  input_coded_size_ = input_coded_size;
+
+  RunCallback(&initialize_callback_, encoder_last_error_);
+}
+
+void VideoEncoderResource::OnPluginMsgGetVideoFramesReply(
+    const ResourceMessageReplyParams& params,
+    uint32_t frame_count,
+    uint32_t frame_length,
+    const PP_Size& frame_size) {
+  int32_t error = params.result();
+  if (error) {
+    NotifyError(error);
+    return;
+  }
+
+  base::SharedMemoryHandle buffer_handle;
+  params.TakeSharedMemoryHandleAtIndex(0, &buffer_handle);
+
+  if (!buffer_manager_.SetBuffers(
+          frame_count, frame_length,
+          make_scoped_ptr(new base::SharedMemory(buffer_handle, false)),
+          true)) {
+    NotifyError(PP_ERROR_FAILED);
+    return;
+  }
+
+  TryWriteVideoFrame();

[bbudge, 2015/02/18 22:53:01]

Shouldn't we check the callback here? i.e.
  if (TrackedCallback::IsPending(get_video_frame_callback_))

The plugin could have called Close() after calling GetVideoFrame.

[llandwerlin-old, 2015/02/19 15:55:45]

I will add the check, but given this is done lazily, it means we at least have a
request from the plugin.

[bbudge, 2015/02/19 20:30:54]

The plugin could call GetVideoFrame and immediately call Close() before we get
here. In that case I think the callback would have been aborted already.

[llandwerlin-old, 2015/02/20 12:19:16]

Ah fair. Thanks!

+}
+
+void VideoEncoderResource::OnPluginMsgEncodeReply(
+    const ResourceMessageReplyParams& params,
+    uint32_t frame_id) {
+  DCHECK_NE(encode_callbacks_.size(), 0U);
+  encoder_last_error_ = params.result();
+
+  scoped_refptr<TrackedCallback> callback = encode_callbacks_.front();

[bbudge, 2015/02/18 22:53:01]

Do we know that the encoder releases video frames in the order in which they're
submitted via Encode()? If that's not true, then we may call the plugin's
callbacks in the wrong order here. In that case, we should use a map instead of
a queue, with the frame_id being the key.

[llandwerlin-old, 2015/02/19 15:55:45]

The current implementations release the frame in order. I can't imagine a
different way.
Switching to a map anyway.

[bbudge, 2015/02/19 20:30:54]

I wasn't sure about this. If it ever wasn't true, the bug would be subtle and
hard to diagnose.

[llandwerlin-old, 2015/02/20 12:19:16]

Acknowledged.

+  encode_callbacks_.pop_front();
+  RunCallback(&callback, encoder_last_error_);
+
+  buffer_manager_.EnqueueBuffer(frame_id);
+  // If the plugin is waiting for a video frame, we can give the one
+  // that just became available again.
+  if (TrackedCallback::IsPending(get_video_frame_callback_))
+    TryWriteVideoFrame();
+}
+
+void VideoEncoderResource::OnPluginMsgBitstreamBuffers(
+    const ResourceMessageReplyParams& params,
+    uint32_t buffer_length) {
+  std::vector<base::SharedMemoryHandle> shm_handles;
+  params.TakeAllSharedMemoryHandles(&shm_handles);
+
+  for (uint32_t i = 0; i < shm_handles.size(); ++i) {
+    scoped_ptr<base::SharedMemory> shm(
+        new base::SharedMemory(shm_handles[i], true));
+    CHECK(shm->Map(buffer_length));
+
+    ShmBuffer* buffer = new ShmBuffer(i, shm.Pass());
+    shm_buffers_.push_back(buffer);
+    bitstream_buffer_map_.insert(
+        std::make_pair(buffer->shm->memory(), buffer->id));
+  }
+}
+
+void VideoEncoderResource::OnPluginMsgBitstreamBufferReady(
+    const ResourceMessageReplyParams& params,
+    uint32_t buffer_id,
+    uint32_t buffer_size,
+    bool key_frame) {
+  available_bitstream_buffers_.push_back(
+      BitstreamBuffer(buffer_id, buffer_size, PP_FromBool(key_frame)));
+
+  if (TrackedCallback::IsPending(get_bitstream_buffer_callback_)) {
+    BitstreamBuffer buffer(available_bitstream_buffers_.front());
+    available_bitstream_buffers_.pop_front();
+    WriteBitstreamBuffer(buffer);
+  }
+}
+
+void VideoEncoderResource::OnPluginMsgNotifyError(
+    const ResourceMessageReplyParams& params,
+    int32_t error) {
+  NotifyError(error);
+}
+
+void VideoEncoderResource::NotifyError(int32_t error) {
+  encoder_last_error_ = error;
+  RunCallback(&get_supported_profiles_callback_, error);
+  RunCallback(&initialize_callback_, error);
+  RunCallback(&get_video_frame_callback_, error);
+  RunCallback(&get_bitstream_buffer_callback_, error);
+  get_bitstream_buffer_data_ = nullptr;
+  while (!encode_callbacks_.empty()) {
+    scoped_refptr<TrackedCallback> callback = encode_callbacks_.front();
+    encode_callbacks_.pop_front();
+    RunCallback(&callback, error);
+  }
+}
+
+void VideoEncoderResource::TryWriteVideoFrame() {
+  int32_t frame_id = buffer_manager_.DequeueBuffer();
+  if (frame_id < 0)
+    return;
+
+  scoped_refptr<VideoFrameResource> resource = new VideoFrameResource(
+      pp_instance(), frame_id, buffer_manager_.GetBufferPointer(frame_id));
+  video_frames_.insert(
+      VideoFrameMap::value_type(resource->pp_resource(), resource));
+
+  *get_video_frame_data_ = resource->GetReference();
+  get_video_frame_data_ = nullptr;
+  RunCallback(&get_video_frame_callback_, PP_OK);
+}
+
+void VideoEncoderResource::WriteBitstreamBuffer(const BitstreamBuffer& buffer) {
+  DCHECK_LT(buffer.id, shm_buffers_.size());
+
+  get_bitstream_buffer_data_->size = buffer.size;
+  get_bitstream_buffer_data_->buffer = shm_buffers_[buffer.id]->shm->memory();
+  get_bitstream_buffer_data_->key_frame = PP_FromBool(buffer.key_frame);
+  get_bitstream_buffer_data_ = nullptr;
+  RunCallback(&get_bitstream_buffer_callback_, PP_OK);
+}
+
+void VideoEncoderResource::ReleaseFrames() {
+  for (VideoFrameMap::iterator it = video_frames_.begin();
+       it != video_frames_.end(); ++it) {
+    it->second->Invalidate();
+    it->second = nullptr;
+  }
+  video_frames_.clear();
 }
 
 }  // namespace proxy
 }  // namespace ppapi