Refactor VideoTrackRecorder into smaller classes

content/renderer/media_recorder/h264_encoder.cc

+// Copyright 2017 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 "content/renderer/media_recorder/h264_encoder.h"
+
+#include <string>
+
+#include "base/bind.h"
+#include "base/threading/thread.h"
+#include "base/trace_event/trace_event.h"
+#include "media/base/video_frame.h"
+#include "third_party/openh264/src/codec/api/svc/codec_app_def.h"
+#include "third_party/openh264/src/codec/api/svc/codec_def.h"
+#include "ui/gfx/geometry/size.h"
+
+using media::VideoFrame;
+
+namespace content {
+
+void H264Encoder::ISVCEncoderDeleter::operator()(ISVCEncoder* codec) {
+  if (!codec)
+    return;
+  const int uninit_ret = codec->Uninitialize();
+  CHECK_EQ(cmResultSuccess, uninit_ret);
+  WelsDestroySVCEncoder(codec);
+}
+
+// static
+void H264Encoder::ShutdownEncoder(std::unique_ptr<base::Thread> encoding_thread,
+                                  ScopedISVCEncoderPtr encoder) {
+  DCHECK(encoding_thread->IsRunning());
+  encoding_thread->Stop();
+  // Both |encoding_thread| and |encoder| will be destroyed at end-of-scope.
+}
+
+H264Encoder::H264Encoder(
+    const VideoTrackRecorder::OnEncodedVideoCB& on_encoded_video_callback,
+    int32_t bits_per_second)
+    : Encoder(on_encoded_video_callback, bits_per_second) {
+  DCHECK(encoding_thread_->IsRunning());
+}
+
+H264Encoder::~H264Encoder() {
+  main_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&H264Encoder::ShutdownEncoder, base::Passed(&encoding_thread_),
+                 base::Passed(&openh264_encoder_)));
+}
+
+void H264Encoder::EncodeOnEncodingTaskRunner(
+    scoped_refptr<VideoFrame> frame,
+    base::TimeTicks capture_timestamp) {
+  TRACE_EVENT0("video", "H264Encoder::EncodeOnEncodingTaskRunner");
+  DCHECK(encoding_task_runner_->BelongsToCurrentThread());
+
+  const gfx::Size frame_size = frame->visible_rect().size();
+  if (!openh264_encoder_ || configured_size_ != frame_size) {
+    ConfigureEncoderOnEncodingTaskRunner(frame_size);
+    first_frame_timestamp_ = capture_timestamp;
+  }
+
+  SSourcePicture picture = {};
+  picture.iPicWidth = frame_size.width();
+  picture.iPicHeight = frame_size.height();
+  picture.iColorFormat = EVideoFormatType::videoFormatI420;
+  picture.uiTimeStamp =
+      (capture_timestamp - first_frame_timestamp_).InMilliseconds();
+  picture.iStride[0] = frame->stride(VideoFrame::kYPlane);
+  picture.iStride[1] = frame->stride(VideoFrame::kUPlane);
+  picture.iStride[2] = frame->stride(VideoFrame::kVPlane);
+  picture.pData[0] = frame->visible_data(VideoFrame::kYPlane);
+  picture.pData[1] = frame->visible_data(VideoFrame::kUPlane);
+  picture.pData[2] = frame->visible_data(VideoFrame::kVPlane);
+
+  SFrameBSInfo info = {};
+  if (openh264_encoder_->EncodeFrame(&picture, &info) != cmResultSuccess) {
+    NOTREACHED() << "OpenH264 encoding failed";
+    return;
+  }
+  const media::WebmMuxer::VideoParameters video_params(frame);
+  frame = nullptr;
+
+  std::unique_ptr<std::string> data(new std::string);
+  const uint8_t kNALStartCode[4] = {0, 0, 0, 1};
+  for (int layer = 0; layer < info.iLayerNum; ++layer) {
+    const SLayerBSInfo& layerInfo = info.sLayerInfo[layer];
+    // Iterate NAL units making up this layer, noting fragments.
+    size_t layer_len = 0;
+    for (int nal = 0; nal < layerInfo.iNalCount; ++nal) {
+      // The following DCHECKs make sure that the header of each NAL unit is OK.
+      DCHECK_GE(layerInfo.pNalLengthInByte[nal], 4);
+      DCHECK_EQ(kNALStartCode[0], layerInfo.pBsBuf[layer_len + 0]);
+      DCHECK_EQ(kNALStartCode[1], layerInfo.pBsBuf[layer_len + 1]);
+      DCHECK_EQ(kNALStartCode[2], layerInfo.pBsBuf[layer_len + 2]);
+      DCHECK_EQ(kNALStartCode[3], layerInfo.pBsBuf[layer_len + 3]);
+
+      layer_len += layerInfo.pNalLengthInByte[nal];
+    }
+    // Copy the entire layer's data (including NAL start codes).
+    data->append(reinterpret_cast<char*>(layerInfo.pBsBuf), layer_len);
+  }
+
+  const bool is_key_frame = info.eFrameType == videoFrameTypeIDR;
+  origin_task_runner_->PostTask(
+      FROM_HERE, base::Bind(OnFrameEncodeCompleted, on_encoded_video_callback_,
+                            video_params, base::Passed(&data), nullptr,
+                            capture_timestamp, is_key_frame));
+}
+
+void H264Encoder::ConfigureEncoderOnEncodingTaskRunner(const gfx::Size& size) {
+  DCHECK(encoding_task_runner_->BelongsToCurrentThread());
+  ISVCEncoder* temp_encoder = nullptr;
+  if (WelsCreateSVCEncoder(&temp_encoder) != 0) {
+    NOTREACHED() << "Failed to create OpenH264 encoder";
+    return;
+  }
+  openh264_encoder_.reset(temp_encoder);
+  configured_size_ = size;
+
+#if DCHECK_IS_ON()
+  int trace_level = WELS_LOG_INFO;
+  openh264_encoder_->SetOption(ENCODER_OPTION_TRACE_LEVEL, &trace_level);
+#endif
+
+  SEncParamExt init_params;
+  openh264_encoder_->GetDefaultParams(&init_params);
+  init_params.iUsageType = CAMERA_VIDEO_REAL_TIME;
+
+  DCHECK_EQ(AUTO_REF_PIC_COUNT, init_params.iNumRefFrame);
+  DCHECK(!init_params.bSimulcastAVC);
+
+  init_params.uiIntraPeriod = 100;  // Same as for VpxEncoder.
+  init_params.iPicWidth = size.width();
+  init_params.iPicHeight = size.height();
+
+  DCHECK_EQ(RC_QUALITY_MODE, init_params.iRCMode);
+  DCHECK_EQ(0, init_params.iPaddingFlag);
+  DCHECK_EQ(UNSPECIFIED_BIT_RATE, init_params.iTargetBitrate);
+  DCHECK_EQ(UNSPECIFIED_BIT_RATE, init_params.iMaxBitrate);
+  if (bits_per_second_ > 0) {
+    init_params.iRCMode = RC_BITRATE_MODE;
+    init_params.iTargetBitrate = bits_per_second_;
+  } else {
+    init_params.iRCMode = RC_OFF_MODE;
+  }
+
+  // Threading model: Set to 1 due to https://crbug.com/583348.
+  init_params.iMultipleThreadIdc = 1;
+
+  // TODO(mcasas): consider reducing complexity if there are few CPUs available.
+  init_params.iComplexityMode = MEDIUM_COMPLEXITY;
+  DCHECK(!init_params.bEnableDenoise);
+  DCHECK(init_params.bEnableFrameSkip);
+
+  // The base spatial layer 0 is the only one we use.
+  DCHECK_EQ(1, init_params.iSpatialLayerNum);
+  init_params.sSpatialLayers[0].iVideoWidth = init_params.iPicWidth;
+  init_params.sSpatialLayers[0].iVideoHeight = init_params.iPicHeight;
+  init_params.sSpatialLayers[0].iSpatialBitrate = init_params.iTargetBitrate;
+
+  // When uiSliceMode = SM_FIXEDSLCNUM_SLICE, uiSliceNum = 0 means auto design
+  // it with cpu core number.
+  // TODO(sprang): Set to 0 when we understand why the rate controller borks
+  // when uiSliceNum > 1. See https://github.com/cisco/openh264/issues/2591
+  init_params.sSpatialLayers[0].sSliceArgument.uiSliceNum = 1;
+  init_params.sSpatialLayers[0].sSliceArgument.uiSliceMode =
+      SM_FIXEDSLCNUM_SLICE;
+
+  if (openh264_encoder_->InitializeExt(&init_params) != cmResultSuccess) {
+    NOTREACHED() << "Failed to initialize OpenH264 encoder";
+    return;
+  }
+
+  int pixel_format = EVideoFormatType::videoFormatI420;
+  openh264_encoder_->SetOption(ENCODER_OPTION_DATAFORMAT, &pixel_format);
+}
+
+}  // namespace content