Implement software fallback for PPB_VideoDecoder.

content/renderer/pepper/video_decoder_shim.cc

+// Copyright (c) 2014 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 <GLES2/gl2.h>
+#include <GLES2/gl2ext.h>
+#include <GLES2/gl2extchromium.h>
+
+#include "content/renderer/pepper/video_decoder_shim.h"
+
+#include "base/bind.h"
+#include "base/numerics/safe_conversions.h"
+#include "content/public/renderer/render_thread.h"
+#include "content/renderer/pepper/pepper_video_decoder_host.h"
+#include "content/renderer/render_thread_impl.h"
+#include "gpu/command_buffer/client/gles2_implementation.h"
+#include "media/base/decoder_buffer.h"
+#include "media/base/limits.h"
+#include "media/base/video_decoder.h"
+#include "media/filters/ffmpeg_video_decoder.h"
+#include "media/video/picture.h"
+#include "media/video/video_decode_accelerator.h"
+#include "ppapi/c/pp_errors.h"
+#include "third_party/libyuv/include/libyuv.h"
+#include "webkit/common/gpu/context_provider_web_context.h"
+
+namespace content {
+
+struct VideoDecoderShim::PendingDecode {
+  PendingDecode(uint32_t decode_id,
+                const scoped_refptr<media::DecoderBuffer>& buffer);
+  ~PendingDecode();
+
+  const uint32_t decode_id;
+  const scoped_refptr<media::DecoderBuffer> buffer;
+};
+
+VideoDecoderShim::PendingDecode::PendingDecode(
+    uint32_t decode_id,
+    const scoped_refptr<media::DecoderBuffer>& buffer)
+    : decode_id(decode_id), buffer(buffer) {
+}
+
+VideoDecoderShim::PendingDecode::~PendingDecode() {
+}
+
+struct VideoDecoderShim::PendingFrame {
+  explicit PendingFrame(uint32_t decode_id);
+  PendingFrame(uint32_t decode_id, const gfx::Size& size);
+  ~PendingFrame();
+
+  const uint32_t decode_id;
+  const gfx::Size size;
+  std::vector<uint8_t> argb_pixels;
+
+ private:
+  // This could be expensive to copy, so guard against that.
+  DISALLOW_COPY_AND_ASSIGN(PendingFrame);
+};
+
+VideoDecoderShim::PendingFrame::PendingFrame(uint32_t decode_id)
+    : decode_id(decode_id) {
+}
+
+VideoDecoderShim::PendingFrame::PendingFrame(uint32_t decode_id,
+                                             const gfx::Size& size)
+    : decode_id(decode_id),
+      size(size),
+      argb_pixels(size.width() * size.height() * 4) {
+}
+
+VideoDecoderShim::PendingFrame::~PendingFrame() {
+}
+
+// DecoderImpl runs the underlying VideoDecoder on the media thread, receiving
+// calls from the VideoDecodeShim on the main thread and sending results back.
+// This class is constructed on the main thread, but used and destructed on the
+// media thread.
+class VideoDecoderShim::DecoderImpl {
+ public:
+  explicit DecoderImpl(const base::WeakPtr<VideoDecoderShim>& proxy);
+  ~DecoderImpl();
+
+  void Initialize(media::VideoDecoderConfig config);
+  void Decode(uint32_t decode_id, scoped_refptr<media::DecoderBuffer> buffer);
+  void Reset();
+  void Stop();
+
+ private:
+  void OnPipelineStatus(media::PipelineStatus status);
+  void DoDecode();
+  void OnDecodeComplete(uint32_t decode_id,
+                        media::VideoDecoder::Status status,
+                        const scoped_refptr<media::VideoFrame>& frame);
+  void OnResetComplete();
+
+  // WeakPtr is bound to main_message_loop_. Use only in shim callbacks.
+  base::WeakPtr<VideoDecoderShim> shim_;
+  scoped_ptr<media::VideoDecoder> decoder_;
+  scoped_refptr<base::MessageLoopProxy> main_message_loop_;
+  // Queue of decodes waiting for the decoder.
+  typedef std::queue<PendingDecode> PendingDecodeQueue;
+  PendingDecodeQueue pending_decodes_;
+  int max_decodes_at_decoder_;
+  int num_decodes_at_decoder_;
+};
+
+VideoDecoderShim::DecoderImpl::DecoderImpl(
+    const base::WeakPtr<VideoDecoderShim>& proxy)
+    : shim_(proxy),
+      main_message_loop_(base::MessageLoopProxy::current()),
+      max_decodes_at_decoder_(0),
+      num_decodes_at_decoder_(0) {
+}
+
+VideoDecoderShim::DecoderImpl::~DecoderImpl() {
+  DCHECK(pending_decodes_.empty());
+}
+
+void VideoDecoderShim::DecoderImpl::Initialize(
+    media::VideoDecoderConfig config) {
+  DCHECK(!decoder_);
+  scoped_ptr<media::FFmpegVideoDecoder> ffmpeg_video_decoder(
+      new media::FFmpegVideoDecoder(base::MessageLoopProxy::current()));
+  ffmpeg_video_decoder->set_decode_nalus(true);

[Ami GONE FROM CHROMIUM, 2014/06/08 17:30:38]

Still concerned that this conflicts with the true low_delay value at l.133.

[bbudge, 2014/06/09 23:33:01]

I'll work this out with Igor.

+  decoder_ = ffmpeg_video_decoder.Pass();
+  max_decodes_at_decoder_ = decoder_->GetMaxDecodeRequests();
+  // We can use base::Unretained() safely in decoder callbacks because we call
+  // VideoDecoder::Stop() before deletion. Stop() guarantees there will be no
+  // outstanding callbacks after it returns.
+  decoder_->Initialize(
+      config,
+      true /* low_delay */,
+      base::Bind(&VideoDecoderShim::DecoderImpl::OnPipelineStatus,
+                 base::Unretained(this)));
+}
+
+void VideoDecoderShim::DecoderImpl::OnPipelineStatus(
+    media::PipelineStatus status) {
+  int32_t result;
+  switch (status) {
+    case media::PIPELINE_OK:
+      result = PP_OK;
+      break;
+    case media::DECODER_ERROR_NOT_SUPPORTED:
+      result = PP_ERROR_NOTSUPPORTED;
+      break;
+    default:
+      result = PP_ERROR_FAILED;
+      break;
+  }
+
+  // Calculate how many textures the shim should create.
+  uint32_t texture_pool_size =
+      max_decodes_at_decoder_ + media::limits::kMaxVideoFrames;
+  main_message_loop_->PostTask(
+      FROM_HERE,
+      base::Bind(&VideoDecoderShim::OnInitializeComplete,
+                 shim_,
+                 result,
+                 texture_pool_size));
+}
+
+void VideoDecoderShim::DecoderImpl::Decode(
+    uint32_t decode_id,
+    scoped_refptr<media::DecoderBuffer> buffer) {
+  DCHECK(decoder_);
+  pending_decodes_.push(PendingDecode(decode_id, buffer));
+  DoDecode();

[Ami GONE FROM CHROMIUM, 2014/06/08 17:30:38]

There are a bunch of encoded test streams in media/test/data.  To test from a
plugin you'd have to set up a demuxer in the plugin, and also hook up file
access.

[bbudge, 2014/06/09 23:33:01]

I was thinking along the lines of some very simple series of frames, like a
sequence of solid color frames, so the data could be compact and so we could
test that the plumbing is correct, rather than exercise the decoder itself.
Also, with some interesting cases like changing the size of textures, and
malformed input data, so we could exercise more of the proxy code.

+}
+
+void VideoDecoderShim::DecoderImpl::Reset() {
+  DCHECK(decoder_);
+  // Abort all pending decodes.
+  while (!pending_decodes_.empty()) {
+    const PendingDecode& decode = pending_decodes_.front();
+    scoped_ptr<PendingFrame> pending_frame(new PendingFrame(decode.decode_id));
+    main_message_loop_->PostTask(FROM_HERE,
+                                 base::Bind(&VideoDecoderShim::OnDecodeComplete,
+                                            shim_,
+                                            media::VideoDecoder::kAborted,
+                                            base::Passed(&pending_frame)));
+    pending_decodes_.pop();
+  }
+  decoder_->Reset(base::Bind(&VideoDecoderShim::DecoderImpl::OnResetComplete,
+                             base::Unretained(this)));
+}
+
+void VideoDecoderShim::DecoderImpl::Stop() {
+  DCHECK(decoder_);
+  // Clear pending decodes now. We don't want OnDecodeComplete to call Decode
+  // again.
+  while (!pending_decodes_.empty())
+    pending_decodes_.pop();
+  decoder_->Stop();
+  // This instance is deleted once we exit this scope.
+}
+
+void VideoDecoderShim::DecoderImpl::DoDecode() {
+  while (!pending_decodes_.empty() &&
+         num_decodes_at_decoder_ < max_decodes_at_decoder_) {
+    num_decodes_at_decoder_++;
+    const PendingDecode& decode = pending_decodes_.front();
+    decoder_->Decode(
+        decode.buffer,
+        base::Bind(&VideoDecoderShim::DecoderImpl::OnDecodeComplete,
+                   base::Unretained(this),
+                   decode.decode_id));
+    pending_decodes_.pop();
+  }
+}
+
+void VideoDecoderShim::DecoderImpl::OnDecodeComplete(
+    uint32_t decode_id,
+    media::VideoDecoder::Status status,
+    const scoped_refptr<media::VideoFrame>& frame) {
+  num_decodes_at_decoder_--;
+  scoped_ptr<PendingFrame> pending_frame;
+  if (status == media::VideoDecoder::kOk && !frame->end_of_stream()) {
+    pending_frame.reset(new PendingFrame(decode_id, frame->coded_size()));
+    // Convert the VideoFrame pixels to ARGB.
+    libyuv::I420ToARGB(frame->data(media::VideoFrame::kYPlane),
+                       frame->stride(media::VideoFrame::kYPlane),
+                       frame->data(media::VideoFrame::kUPlane),
+                       frame->stride(media::VideoFrame::kUPlane),
+                       frame->data(media::VideoFrame::kVPlane),
+                       frame->stride(media::VideoFrame::kVPlane),
+                       &pending_frame->argb_pixels.front(),
+                       frame->coded_size().width() * 4,
+                       frame->coded_size().width(),
+                       frame->coded_size().height());
+  } else {
+    pending_frame.reset(new PendingFrame(decode_id));
+  }
+
+  int32_t result;
+  switch (status) {
+    case media::VideoDecoder::kOk:
+    // We allow partial frames, so this is OK.
+    case media::VideoDecoder::kNotEnoughData:
+      result = PP_OK;
+      break;
+    case media::VideoDecoder::kAborted:
+      result = PP_ERROR_ABORTED;
+      break;
+    case media::VideoDecoder::kDecodeError:
+      result = PP_ERROR_RESOURCE_FAILED;
+      break;
+    default:
+      NOTREACHED();
+      result = PP_ERROR_FAILED;
+      break;
+  }
+
+  main_message_loop_->PostTask(FROM_HERE,
+                               base::Bind(&VideoDecoderShim::OnDecodeComplete,
+                                          shim_,
+                                          result,
+                                          base::Passed(&pending_frame)));
+
+  DoDecode();
+}
+
+void VideoDecoderShim::DecoderImpl::OnResetComplete() {
+  main_message_loop_->PostTask(
+      FROM_HERE, base::Bind(&VideoDecoderShim::OnResetComplete, shim_));
+}
+
+VideoDecoderShim::VideoDecoderShim(PepperVideoDecoderHost* host)
+    : state_(UNINITIALIZED),
+      host_(host),
+      media_message_loop_(
+          RenderThreadImpl::current()->GetMediaThreadMessageLoopProxy()),
+      context_provider_(
+          RenderThreadImpl::current()->SharedMainThreadContextProvider()),
+      num_pending_decodes_(0),
+      texture_pool_size_(0),
+      weak_ptr_factory_(this) {
+  DCHECK(host_);
+  DCHECK(media_message_loop_);
+  DCHECK(context_provider_);
+  decoder_impl_.reset(new DecoderImpl(weak_ptr_factory_.GetWeakPtr()));
+}
+
+VideoDecoderShim::~VideoDecoderShim() {
+  DCHECK(RenderThreadImpl::current());
+  // Delete any remaining textures.
+  TextureIdMap::iterator it = texture_id_map_.begin();
+  for (; it != texture_id_map_.end(); ++it)
+    DeleteTexture(it->second);
+  texture_id_map_.clear();
+
+  FlushCommandBuffer();
+
+  host_ = NULL;
+  // No methods can post tasks to the delegate now.
+  weak_ptr_factory_.InvalidateWeakPtrs();
+  // No more callbacks from the delegate will be received now.
+
+  // The callback now holds the only reference to the DecoderImpl, which will be
+  // deleted when Stop completes.
+  media_message_loop_->PostTask(
+      FROM_HERE,
+      base::Bind(&VideoDecoderShim::DecoderImpl::Stop,
+                 base::Owned(decoder_impl_.release())));
+
+}
+
+bool VideoDecoderShim::Initialize(
+    media::VideoCodecProfile profile,
+    media::VideoDecodeAccelerator::Client* client) {
+  DCHECK_EQ(client, host_);
+  DCHECK(RenderThreadImpl::current());
+  DCHECK_EQ(state_, UNINITIALIZED);
+  media::VideoCodec codec = media::kUnknownVideoCodec;
+  if (profile <= media::H264PROFILE_MAX)
+    codec = media::kCodecH264;
+  else if (profile <= media::VP8PROFILE_MAX)
+    codec = media::kCodecVP8;
+  DCHECK_NE(codec, media::kUnknownVideoCodec);
+
+  media::VideoDecoderConfig config(
+      codec,
+      profile,
+      media::VideoFrame::YV12,
+      gfx::Size(32, 24),  // Small sizes that won't fail.
+      gfx::Rect(32, 24),
+      gfx::Size(32, 24),
+      NULL /* extra_data */,  // TODO(bbudge) Verify this isn't needed.
+      0 /* extra_data_size */,
+      false /* decryption */);
+
+  media_message_loop_->PostTask(
+      FROM_HERE,
+      base::Bind(&VideoDecoderShim::DecoderImpl::Initialize,
+                 base::Unretained(decoder_impl_.get()),
+                 config));
+  // Return success, even though we are asynchronous, to mimic
+  // media::VideoDecodeAccelerator.
+  return true;
+}
+
+void VideoDecoderShim::Decode(const media::BitstreamBuffer& bitstream_buffer) {
+  DCHECK(RenderThreadImpl::current());
+  DCHECK_EQ(state_, DECODING);
+
+  num_pending_decodes_++;
+
+  // We need the address of the shared memory, so we can copy into our buffer.
+  const uint8_t* buffer = host_->DecodeIdToAddress(bitstream_buffer.id());
+  DCHECK(buffer);
+
+  media_message_loop_->PostTask(
+      FROM_HERE,
+      base::Bind(
+          &VideoDecoderShim::DecoderImpl::Decode,
+          base::Unretained(decoder_impl_.get()),
+          bitstream_buffer.id(),
+          media::DecoderBuffer::CopyFrom(buffer, bitstream_buffer.size())));
+}
+
+void VideoDecoderShim::AssignPictureBuffers(
+    const std::vector<media::PictureBuffer>& buffers) {
+  DCHECK(RenderThreadImpl::current());
+  DCHECK_EQ(state_, DECODING);
+  if (buffers.empty()) {
+    NOTREACHED();
+    return;
+  }
+  DCHECK_EQ(buffers.size(), pending_texture_mailboxes_.size());
+  GLuint num_textures = base::checked_cast<GLuint>(buffers.size());
+  std::vector<uint32_t> local_texture_ids(num_textures);
+  gpu::gles2::GLES2Interface* gles2 = context_provider_->ContextGL();
+  gles2->GenTextures(num_textures, &local_texture_ids.front());
+  for (uint32_t i = 0; i < num_textures; i++) {
+    gles2->ActiveTexture(GL_TEXTURE0);
+    gles2->BindTexture(GL_TEXTURE_2D, local_texture_ids[i]);
+    gles2->ConsumeTextureCHROMIUM(GL_TEXTURE_2D,
+                                  pending_texture_mailboxes_[i].name);
+    // Map the plugin texture id to the local texture id.
+    uint32_t plugin_texture_id = buffers[i].texture_id();
+    texture_id_map_[plugin_texture_id] = local_texture_ids[i];
+    available_textures_.push_back(plugin_texture_id);
+  }
+  pending_texture_mailboxes_.clear();
+  SendPictures();
+}
+
+void VideoDecoderShim::ReusePictureBuffer(int32 picture_buffer_id) {
+  DCHECK(RenderThreadImpl::current());
+  uint32_t texture_id = static_cast<uint32_t>(picture_buffer_id);
+  if (textures_to_dismiss_.find(texture_id) != textures_to_dismiss_.end()) {
+    DismissTexture(texture_id);
+  } else if (texture_id_map_.find(texture_id) != texture_id_map_.end()) {
+    available_textures_.push_back(texture_id);
+    SendPictures();
+  } else {
+    NOTREACHED();
+  }
+}
+
+void VideoDecoderShim::Flush() {
+  DCHECK(RenderThreadImpl::current());
+  DCHECK_EQ(state_, DECODING);
+  state_ = FLUSHING;
+}
+
+void VideoDecoderShim::Reset() {
+  DCHECK(RenderThreadImpl::current());
+  DCHECK_EQ(state_, DECODING);
+  state_ = RESETTING;
+  media_message_loop_->PostTask(
+      FROM_HERE,
+      base::Bind(&VideoDecoderShim::DecoderImpl::Reset,
+                 base::Unretained(decoder_impl_.get())));
+}
+
+void VideoDecoderShim::Destroy() {
+  // This will be called, but our destructor can do the actual work.
+}
+
+void VideoDecoderShim::OnInitializeComplete(int32_t result,
+                                            uint32_t texture_pool_size) {
+  DCHECK(RenderThreadImpl::current());
+  DCHECK(host_);
+
+  if (result == PP_OK) {
+    state_ = DECODING;
+    texture_pool_size_ = texture_pool_size;
+  }
+
+  host_->OnInitializeComplete(result);
+}
+
+void VideoDecoderShim::OnDecodeComplete(int32_t result,
+                                        scoped_ptr<PendingFrame> frame) {
+  DCHECK(RenderThreadImpl::current());
+  DCHECK(host_);
+
+  num_pending_decodes_--;
+
+  if (result == PP_OK && !frame->argb_pixels.empty()) {
+    if (texture_size_ != frame->size) {
+      // If the size has changed, all current textures must be dismissed. Add
+      // all textures to |textures_to_dismiss_| and dismiss any that aren't in
+      // use by the plugin. We dismiss the rest as they are recycled.
+      for (TextureIdMap::const_iterator it = texture_id_map_.begin();
+           it != texture_id_map_.end();
+           ++it) {
+        textures_to_dismiss_.insert(it->second);
+      }
+      for (std::vector<uint32_t>::const_iterator it =
+               available_textures_.begin();
+           it != available_textures_.end();
+           ++it) {
+        DismissTexture(*it);
+      }
+      available_textures_.clear();
+      FlushCommandBuffer();
+
+      DCHECK(pending_texture_mailboxes_.empty());
+      for (uint32_t i = 0; i < texture_pool_size_; i++)
+        pending_texture_mailboxes_.push_back(gpu::Mailbox::Generate());
+
+      host_->RequestTextures(texture_pool_size_,
+                             frame->size,
+                             GL_TEXTURE_2D,
+                             pending_texture_mailboxes_);
+      texture_size_ = frame->size;
+    }
+
+    pending_frames_.push(linked_ptr<PendingFrame>(frame.release()));
+    SendPictures();
+  } else {
+    host_->NotifyEndOfBitstreamBuffer(frame->decode_id);
+  }
+
+  // Report any VDA type errors.
+  if (result == PP_ERROR_RESOURCE_FAILED)
+    host_->NotifyError(media::VideoDecodeAccelerator::PLATFORM_FAILURE);
+}
+
+void VideoDecoderShim::SendPictures() {
+  DCHECK(RenderThreadImpl::current());
+  DCHECK(host_);
+
+  while (!pending_frames_.empty() && !available_textures_.empty()) {
+    const linked_ptr<PendingFrame>& frame = pending_frames_.front();
+
+    uint32_t texture_id = available_textures_.back();
+    available_textures_.pop_back();
+
+    uint32_t local_texture_id = texture_id_map_[texture_id];
+    gpu::gles2::GLES2Interface* gles2 = context_provider_->ContextGL();
+    gles2->ActiveTexture(GL_TEXTURE0);
+    gles2->BindTexture(GL_TEXTURE_2D, local_texture_id);
+    gles2->TexImage2D(GL_TEXTURE_2D,
+                      0,
+                      GL_RGBA,
+                      texture_size_.width(),
+                      texture_size_.height(),
+                      0,
+                      GL_RGBA,
+                      GL_UNSIGNED_BYTE,
+                      &frame->argb_pixels.front());
+
+    host_->NotifyEndOfBitstreamBuffer(frame->decode_id);
+    host_->PictureReady(media::Picture(texture_id, frame->decode_id));
+    pending_frames_.pop();
+  }
+
+  FlushCommandBuffer();
+
+  if (state_ == FLUSHING && !num_pending_decodes_ && pending_frames_.empty()) {
+    state_ = DECODING;
+    host_->NotifyFlushDone();
+  }
+}
+
+void VideoDecoderShim::OnResetComplete() {
+  DCHECK(RenderThreadImpl::current());
+  DCHECK(host_);
+
+  while (!pending_frames_.empty()) {
+    const linked_ptr<PendingFrame>& frame = pending_frames_.front();
+    host_->NotifyEndOfBitstreamBuffer(frame->decode_id);
+    pending_frames_.pop();
+  }
+
+  state_ = DECODING;
+  host_->NotifyResetDone();
+}
+
+void VideoDecoderShim::DismissTexture(uint32_t texture_id) {
+  DCHECK(host_);
+  textures_to_dismiss_.erase(texture_id);
+  DCHECK(texture_id_map_.find(texture_id) != texture_id_map_.end());
+  DeleteTexture(texture_id_map_[texture_id]);
+  texture_id_map_.erase(texture_id);
+  host_->DismissPictureBuffer(texture_id);
+}
+
+void VideoDecoderShim::DeleteTexture(uint32_t texture_id) {
+  gpu::gles2::GLES2Interface* gles2 = context_provider_->ContextGL();
+  gles2->DeleteTextures(1, &texture_id);
+}
+
+void VideoDecoderShim::FlushCommandBuffer() {
+  context_provider_->ContextGL()->Flush();
+}
+
+}  // namespace content