1 files changed, 308 insertions, 0 deletions
diff --git a/third_party/libwebrtc/webrtc/media/engine/videoencodersoftwarefallbackwrapper.cc b/third_party/libwebrtc/webrtc/media/engine/videoencodersoftwarefallbackwrapper.cc
new file mode 100644
index 0000000000..69254f5fb5
--- /dev/null
+++ b/third_party/libwebrtc/webrtc/media/engine/videoencodersoftwarefallbackwrapper.cc
@@ -0,0 +1,308 @@
+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "media/engine/videoencodersoftwarefallbackwrapper.h"
+
+#include <utility>
+
+#include "media/base/h264_profile_level_id.h"
+#include "media/engine/internalencoderfactory.h"
+#include "modules/video_coding/include/video_error_codes.h"
+#include "rtc_base/checks.h"
+#include "rtc_base/logging.h"
+#include "rtc_base/timeutils.h"
+#include "system_wrappers/include/field_trial.h"
+
+namespace webrtc {
+namespace {
+const char kVp8ForceFallbackEncoderFieldTrial[] =
+    "WebRTC-VP8-Forced-Fallback-Encoder-v2";
+
+bool EnableForcedFallback() {
+  return field_trial::IsEnabled(kVp8ForceFallbackEncoderFieldTrial);
+}
+
+bool IsForcedFallbackPossible(const VideoCodec& codec_settings) {
+  return codec_settings.codecType == kVideoCodecVP8 &&
+         codec_settings.numberOfSimulcastStreams <= 1 &&
+         codec_settings.VP8().numberOfTemporalLayers == 1;
+}
+
+void GetForcedFallbackParamsFromFieldTrialGroup(int* param_min_pixels,
+                                                int* param_max_pixels,
+                                                int minimum_max_pixels) {
+  RTC_DCHECK(param_min_pixels);
+  RTC_DCHECK(param_max_pixels);
+  std::string group =
+      webrtc::field_trial::FindFullName(kVp8ForceFallbackEncoderFieldTrial);
+  if (group.empty())
+    return;
+
+  int min_pixels;
+  int max_pixels;
+  int min_bps;
+  if (sscanf(group.c_str(), "Enabled-%d,%d,%d", &min_pixels, &max_pixels,
+             &min_bps) != 3) {
+    RTC_LOG(LS_WARNING)
+        << "Invalid number of forced fallback parameters provided.";
+    return;
+  }
+  if (min_pixels <= 0 || max_pixels < minimum_max_pixels ||
+      max_pixels < min_pixels || min_bps <= 0) {
+    RTC_LOG(LS_WARNING) << "Invalid forced fallback parameter value provided.";
+    return;
+  }
+  *param_min_pixels = min_pixels;
+  *param_max_pixels = max_pixels;
+}
+}  // namespace
+
+VideoEncoderSoftwareFallbackWrapper::VideoEncoderSoftwareFallbackWrapper(
+    std::unique_ptr<webrtc::VideoEncoder> sw_encoder,
+    std::unique_ptr<webrtc::VideoEncoder> hw_encoder)
+    : number_of_cores_(0),
+      max_payload_size_(0),
+      rates_set_(false),
+      framerate_(0),
+      channel_parameters_set_(false),
+      packet_loss_(0),
+      rtt_(0),
+      use_fallback_encoder_(false),
+      encoder_(std::move(hw_encoder)),
+      fallback_encoder_(std::move(sw_encoder)),
+      callback_(nullptr),
+      forced_fallback_possible_(EnableForcedFallback()) {
+  if (forced_fallback_possible_) {
+    GetForcedFallbackParamsFromFieldTrialGroup(
+        &forced_fallback_.min_pixels_, &forced_fallback_.max_pixels_,
+        encoder_->GetScalingSettings().min_pixels_per_frame -
+            1);  // No HW below.
+  }
+}
+
+bool VideoEncoderSoftwareFallbackWrapper::InitFallbackEncoder() {
+  RTC_LOG(LS_WARNING) << "Encoder falling back to software encoding.";
+
+  const int ret = fallback_encoder_->InitEncode(
+      &codec_settings_, number_of_cores_, max_payload_size_);
+  use_fallback_encoder_ = (ret == WEBRTC_VIDEO_CODEC_OK);
+  if (!use_fallback_encoder_) {
+    RTC_LOG(LS_ERROR) << "Failed to initialize software-encoder fallback.";
+    fallback_encoder_->Release();
+    return false;
+  }
+  // Replay callback, rates, and channel parameters.
+  if (callback_)
+    fallback_encoder_->RegisterEncodeCompleteCallback(callback_);
+  if (rates_set_)
+    fallback_encoder_->SetRateAllocation(bitrate_allocation_, framerate_);
+  if (channel_parameters_set_)
+    fallback_encoder_->SetChannelParameters(packet_loss_, rtt_);
+
+  // Since we're switching to the fallback encoder, Release the real encoder. It
+  // may be re-initialized via InitEncode later, and it will continue to get
+  // Set calls for rates and channel parameters in the meantime.
+  encoder_->Release();
+  return true;
+}
+
+int32_t VideoEncoderSoftwareFallbackWrapper::InitEncode(
+    const VideoCodec* codec_settings,
+    int32_t number_of_cores,
+    size_t max_payload_size) {
+  // Store settings, in case we need to dynamically switch to the fallback
+  // encoder after a failed Encode call.
+  codec_settings_ = *codec_settings;
+  number_of_cores_ = number_of_cores;
+  max_payload_size_ = max_payload_size;
+  // Clear stored rate/channel parameters.
+  rates_set_ = false;
+  channel_parameters_set_ = false;
+  ValidateSettingsForForcedFallback();
+
+  // Try to reinit forced software codec if it is in use.
+  if (TryReInitForcedFallbackEncoder()) {
+    return WEBRTC_VIDEO_CODEC_OK;
+  }
+  // Try to init forced software codec if it should be used.
+  if (TryInitForcedFallbackEncoder()) {
+    return WEBRTC_VIDEO_CODEC_OK;
+  }
+  forced_fallback_.active_ = false;
+
+  int32_t ret =
+      encoder_->InitEncode(codec_settings, number_of_cores, max_payload_size);
+  if (ret == WEBRTC_VIDEO_CODEC_OK) {
+    if (use_fallback_encoder_) {
+      RTC_LOG(LS_WARNING)
+          << "InitEncode OK, no longer using the software fallback encoder.";
+      fallback_encoder_->Release();
+      use_fallback_encoder_ = false;
+    }
+    if (callback_)
+      encoder_->RegisterEncodeCompleteCallback(callback_);
+    return ret;
+  }
+  // Try to instantiate software codec.
+  if (InitFallbackEncoder()) {
+    return WEBRTC_VIDEO_CODEC_OK;
+  }
+  // Software encoder failed, use original return code.
+  return ret;
+}
+
+int32_t VideoEncoderSoftwareFallbackWrapper::RegisterEncodeCompleteCallback(
+    EncodedImageCallback* callback) {
+  callback_ = callback;
+  int32_t ret = encoder_->RegisterEncodeCompleteCallback(callback);
+  if (use_fallback_encoder_)
+    return fallback_encoder_->RegisterEncodeCompleteCallback(callback);
+  return ret;
+}
+
+int32_t VideoEncoderSoftwareFallbackWrapper::Release() {
+  return use_fallback_encoder_ ? fallback_encoder_->Release()
+                               : encoder_->Release();
+}
+
+int32_t VideoEncoderSoftwareFallbackWrapper::Encode(
+    const VideoFrame& frame,
+    const CodecSpecificInfo* codec_specific_info,
+    const std::vector<FrameType>* frame_types) {
+  if (use_fallback_encoder_)
+    return fallback_encoder_->Encode(frame, codec_specific_info, frame_types);
+  int32_t ret = encoder_->Encode(frame, codec_specific_info, frame_types);
+  // If requested, try a software fallback.
+  bool fallback_requested = (ret == WEBRTC_VIDEO_CODEC_FALLBACK_SOFTWARE);
+  if (fallback_requested && InitFallbackEncoder()) {
+    if (frame.video_frame_buffer()->type() == VideoFrameBuffer::Type::kNative &&
+        !fallback_encoder_->SupportsNativeHandle()) {
+      RTC_LOG(LS_WARNING) << "Fallback encoder doesn't support native frames, "
+                          << "dropping one frame.";
+      return WEBRTC_VIDEO_CODEC_ERROR;
+    }
+
+    // Start using the fallback with this frame.
+    return fallback_encoder_->Encode(frame, codec_specific_info, frame_types);
+  }
+  return ret;
+}
+
+int32_t VideoEncoderSoftwareFallbackWrapper::SetChannelParameters(
+    uint32_t packet_loss,
+    int64_t rtt) {
+  channel_parameters_set_ = true;
+  packet_loss_ = packet_loss;
+  rtt_ = rtt;
+  int32_t ret = encoder_->SetChannelParameters(packet_loss, rtt);
+  if (use_fallback_encoder_)
+    return fallback_encoder_->SetChannelParameters(packet_loss, rtt);
+  return ret;
+}
+
+int32_t VideoEncoderSoftwareFallbackWrapper::SetRateAllocation(
+    const BitrateAllocation& bitrate_allocation,
+    uint32_t framerate) {
+  rates_set_ = true;
+  bitrate_allocation_ = bitrate_allocation;
+  framerate_ = framerate;
+  int32_t ret = encoder_->SetRateAllocation(bitrate_allocation_, framerate);
+  if (use_fallback_encoder_)
+    return fallback_encoder_->SetRateAllocation(bitrate_allocation_, framerate);
+  return ret;
+}
+
+bool VideoEncoderSoftwareFallbackWrapper::SupportsNativeHandle() const {
+  return use_fallback_encoder_ ? fallback_encoder_->SupportsNativeHandle()
+                               : encoder_->SupportsNativeHandle();
+}
+
+VideoEncoder::ScalingSettings
+VideoEncoderSoftwareFallbackWrapper::GetScalingSettings() const {
+  if (forced_fallback_possible_) {
+    if (forced_fallback_.active_) {
+      return VideoEncoder::ScalingSettings(
+          codec_settings_.VP8().automaticResizeOn,
+          forced_fallback_.min_pixels_);
+    }
+    const auto settings = encoder_->GetScalingSettings();
+    if (settings.thresholds) {
+      return VideoEncoder::ScalingSettings(
+          settings.enabled, settings.thresholds->low, settings.thresholds->high,
+          forced_fallback_.min_pixels_);
+    }
+    return VideoEncoder::ScalingSettings(settings.enabled,
+                                         forced_fallback_.min_pixels_);
+  }
+  return encoder_->GetScalingSettings();
+}
+
+const char* VideoEncoderSoftwareFallbackWrapper::ImplementationName() const {
+  return use_fallback_encoder_ ? fallback_encoder_->ImplementationName()
+                               : encoder_->ImplementationName();
+}
+
+bool VideoEncoderSoftwareFallbackWrapper::IsForcedFallbackActive() const {
+  return (forced_fallback_possible_ && use_fallback_encoder_ &&
+          forced_fallback_.active_);
+}
+
+bool VideoEncoderSoftwareFallbackWrapper::TryInitForcedFallbackEncoder() {
+  if (!forced_fallback_possible_ || use_fallback_encoder_) {
+    return false;
+  }
+  // Fallback not active.
+  if (!forced_fallback_.IsValid(codec_settings_)) {
+    return false;
+  }
+  // Settings valid, try to instantiate software codec.
+  RTC_LOG(LS_INFO) << "Request forced SW encoder fallback: "
+                   << codec_settings_.width << "x" << codec_settings_.height;
+  if (!InitFallbackEncoder()) {
+    return false;
+  }
+  forced_fallback_.active_ = true;
+  return true;
+}
+
+bool VideoEncoderSoftwareFallbackWrapper::TryReInitForcedFallbackEncoder() {
+  if (!IsForcedFallbackActive()) {
+    return false;
+  }
+  // Forced fallback active.
+  if (!forced_fallback_.IsValid(codec_settings_)) {
+    RTC_LOG(LS_INFO) << "Stop forced SW encoder fallback, max pixels exceeded.";
+    return false;
+  }
+  // Settings valid, reinitialize the forced fallback encoder.
+  if (fallback_encoder_->InitEncode(&codec_settings_, number_of_cores_,
+                                    max_payload_size_) !=
+      WEBRTC_VIDEO_CODEC_OK) {
+    RTC_LOG(LS_ERROR) << "Failed to init forced SW encoder fallback.";
+    return false;
+  }
+  return true;
+}
+
+void VideoEncoderSoftwareFallbackWrapper::ValidateSettingsForForcedFallback() {
+  if (!forced_fallback_possible_)
+    return;
+
+  if (!IsForcedFallbackPossible(codec_settings_)) {
+    if (IsForcedFallbackActive()) {
+      fallback_encoder_->Release();
+      use_fallback_encoder_ = false;
+    }
+    RTC_LOG(LS_INFO) << "Disable forced_fallback_possible_ due to settings.";
+    forced_fallback_possible_ = false;
+  }
+}
+
+}  // namespace webrtc