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Throttle frame-rate In VP8 encoder in steady state for screenshare

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If minQP is reached and encoder undershoot consistently, we consider the
quality good enough and throttle encode frame rate.

Bug: webrtc:10310
Change-Id: Ifd07280040dd67ef6e544efdd4619d47bff951e8
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/125461
Reviewed-by: Erik Språng <sprang@webrtc.org>
Commit-Queue: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27003}
This commit is contained in:
Ilya Nikolaevskiy
2019-03-06 16:40:42 +01:00
committed by Commit Bot
parent 2ecc8c8be2
commit 7b41225156
4 changed files with 156 additions and 23 deletions
Download Patch File Download Diff File Expand all files Collapse all files

118
modules/video_coding/codecs/vp8/libvpx_vp8_encoder.cc
View File

@ -32,6 +32,7 @@
#include "modules/video_coding/utility/simulcast_utility.h"
#include "rtc_base/checks.h"
#include "rtc_base/experiments/field_trial_parser.h"
#include "rtc_base/experiments/field_trial_units.h"
#include "rtc_base/trace_event.h"
#include "system_wrappers/include/field_trial.h"
#include "third_party/libyuv/include/libyuv/scale.h"
@ -53,6 +54,9 @@ constexpr int kHighVp8QpThreshold = 95;
constexpr int kTokenPartitions = VP8_ONE_TOKENPARTITION;
constexpr uint32_t kVp832ByteAlign = 32u;
constexpr int kRtpTicksPerSecond = 90000;
constexpr int kRtpTicksPerMs = kRtpTicksPerSecond / 1000;
// VP8 denoiser states.
enum denoiserState : uint32_t {
kDenoiserOff,
@ -173,7 +177,11 @@ LibvpxVp8Encoder::LibvpxVp8Encoder(std::unique_ptr<LibvpxInterface> interface)
cpu_speed_default_(-6),
number_of_cores_(0),
rc_max_intra_target_(0),
key_frame_request_(kMaxSimulcastStreams, false) {
key_frame_request_(kMaxSimulcastStreams, false),
variable_framerate_experiment_(ParseVariableFramerateConfig(
"WebRTC-VP8VariableFramerateScreenshare")),
framerate_controller_(variable_framerate_experiment_.framerate_limit),
num_steady_state_frames_(0) {
temporal_layers_.reserve(kMaxSimulcastStreams);
raw_images_.reserve(kMaxSimulcastStreams);
encoded_images_.reserve(kMaxSimulcastStreams);
@ -392,7 +400,7 @@ int LibvpxVp8Encoder::InitEncode(const VideoCodec* inst,
}
// setting the time base of the codec
configurations_[0].g_timebase.num = 1;
configurations_[0].g_timebase.den = 90000;
configurations_[0].g_timebase.den = kRtpTicksPerSecond;
configurations_[0].g_lag_in_frames = 0; // 0- no frame lagging
// Set the error resilience mode for temporal layers (but not simulcast).
@ -690,6 +698,39 @@ uint32_t LibvpxVp8Encoder::FrameDropThreshold(size_t spatial_idx) const {
return enable_frame_dropping ? 30 : 0;
}
size_t LibvpxVp8Encoder::SteadyStateSize(int sid, int tid) {
const int encoder_id = encoders_.size() - 1 - sid;
size_t bitrate_bps;
float fps;
if (SimulcastUtility::IsConferenceModeScreenshare(codec_) ||
configurations_[encoder_id].ts_number_layers <= 1) {
// In conference screenshare there's no defined per temporal layer bitrate
// and framerate.
bitrate_bps = configurations_[encoder_id].rc_target_bitrate * 1000;
fps = codec_.maxFramerate;
} else {
bitrate_bps = configurations_[encoder_id].ts_target_bitrate[tid] * 1000;
fps = codec_.maxFramerate /
fmax(configurations_[encoder_id].ts_rate_decimator[tid], 1.0);
if (tid > 0) {
// Layer bitrate and fps are counted as a partial sums.
bitrate_bps -=
configurations_[encoder_id].ts_target_bitrate[tid - 1] * 1000;
fps = codec_.maxFramerate /
fmax(configurations_[encoder_id].ts_rate_decimator[tid - 1], 1.0);
}
}
if (fps < 1e-9)
return 0;
return static_cast<size_t>(
bitrate_bps / (8 * fps) *
(100 -
variable_framerate_experiment_.steady_state_undershoot_percentage) /
100 +
0.5);
}
int LibvpxVp8Encoder::Encode(const VideoFrame& frame,
const CodecSpecificInfo* codec_specific_info,
const std::vector<FrameType>* frame_types) {
@ -701,6 +742,33 @@ int LibvpxVp8Encoder::Encode(const VideoFrame& frame,
if (encoded_complete_callback_ == NULL)
return WEBRTC_VIDEO_CODEC_UNINITIALIZED;
bool send_key_frame = false;
for (size_t i = 0; i < key_frame_request_.size() && i < send_stream_.size();
++i) {
if (key_frame_request_[i] && send_stream_[i]) {
send_key_frame = true;
break;
}
}
if (!send_key_frame && frame_types) {
for (size_t i = 0; i < frame_types->size() && i < send_stream_.size();
++i) {
if ((*frame_types)[i] == kVideoFrameKey && send_stream_[i]) {
send_key_frame = true;
break;
}
}
}
if (frame.update_rect().IsEmpty() && num_steady_state_frames_ >= 3 &&
!send_key_frame) {
if (variable_framerate_experiment_.enabled &&
framerate_controller_.DropFrame(frame.timestamp() / kRtpTicksPerMs)) {
return WEBRTC_VIDEO_CODEC_OK;
}
framerate_controller_.AddFrame(frame.timestamp() / kRtpTicksPerMs);
}
rtc::scoped_refptr<I420BufferInterface> input_image =
frame.video_frame_buffer()->ToI420();
// Since we are extracting raw pointers from |input_image| to
@ -736,23 +804,7 @@ int LibvpxVp8Encoder::Encode(const VideoFrame& frame,
raw_images_[i].stride[VPX_PLANE_V], raw_images_[i].d_w,
raw_images_[i].d_h, libyuv::kFilterBilinear);
}
bool send_key_frame = false;
for (size_t i = 0; i < key_frame_request_.size() && i < send_stream_.size();
++i) {
if (key_frame_request_[i] && send_stream_[i]) {
send_key_frame = true;
break;
}
}
if (!send_key_frame && frame_types) {
for (size_t i = 0; i < frame_types->size() && i < send_stream_.size();
++i) {
if ((*frame_types)[i] == kVideoFrameKey && send_stream_[i]) {
send_key_frame = true;
break;
}
}
}
vpx_enc_frame_flags_t flags[kMaxSimulcastStreams];
Vp8FrameConfig tl_configs[kMaxSimulcastStreams];
for (size_t i = 0; i < encoders_.size(); ++i) {
@ -812,7 +864,7 @@ int LibvpxVp8Encoder::Encode(const VideoFrame& frame,
// rate control seems to be off with that setup. Using the average input
// frame rate to calculate an average duration for now.
assert(codec_.maxFramerate > 0);
uint32_t duration = 90000 / codec_.maxFramerate;
uint32_t duration = kRtpTicksPerSecond / codec_.maxFramerate;
int error = WEBRTC_VIDEO_CODEC_OK;
int num_tries = 0;
@ -924,6 +976,14 @@ int LibvpxVp8Encoder::GetEncodedPartitions(const VideoFrame& input_image) {
encoded_images_[encoder_idx].qp_ = qp_128;
encoded_complete_callback_->OnEncodedImage(encoded_images_[encoder_idx],
&codec_specific, nullptr);
const size_t steady_state_size = SteadyStateSize(
stream_idx, codec_specific.codecSpecific.VP8.temporalIdx);
if (qp_128 > variable_framerate_experiment_.steady_state_qp ||
encoded_images_[encoder_idx].size() > steady_state_size) {
num_steady_state_frames_ = 0;
} else {
++num_steady_state_frames_;
}
} else if (!temporal_layers_[stream_idx]
->SupportsEncoderFrameDropping()) {
result = WEBRTC_VIDEO_CODEC_TARGET_BITRATE_OVERSHOOT;
@ -989,4 +1049,22 @@ int LibvpxVp8Encoder::RegisterEncodeCompleteCallback(
return WEBRTC_VIDEO_CODEC_OK;
}
// static
LibvpxVp8Encoder::VariableFramerateExperiment
LibvpxVp8Encoder::ParseVariableFramerateConfig(std::string group_name) {
FieldTrialFlag enabled = FieldTrialFlag("Enabled");
FieldTrialParameter<double> framerate_limit("min_fps", 5.0);
FieldTrialParameter<int> qp("min_qp", 15);
FieldTrialParameter<int> undershoot_percentage("undershoot", 30);
ParseFieldTrial({&enabled, &framerate_limit, &qp, &undershoot_percentage},
field_trial::FindFullName(group_name));
VariableFramerateExperiment config;
config.enabled = enabled.Get();
config.framerate_limit = framerate_limit.Get();
config.steady_state_qp = qp.Get();
config.steady_state_undershoot_percentage = undershoot_percentage.Get();
return config;
}
} // namespace webrtc

20
modules/video_coding/codecs/vp8/libvpx_vp8_encoder.h
View File

@ -12,6 +12,7 @@
#define MODULES_VIDEO_CODING_CODECS_VP8_LIBVPX_VP8_ENCODER_H_
#include <memory>
#include <string>
#include <vector>
#include "api/video/encoded_image.h"
@ -23,6 +24,7 @@
#include "modules/video_coding/codecs/vp8/include/vp8.h"
#include "modules/video_coding/codecs/vp8/libvpx_interface.h"
#include "modules/video_coding/include/video_codec_interface.h"
#include "modules/video_coding/utility/framerate_controller.h"
#include "rtc_base/experiments/cpu_speed_experiment.h"
#include "rtc_base/experiments/rate_control_settings.h"
@ -83,6 +85,8 @@ class LibvpxVp8Encoder : public VideoEncoder {
uint32_t FrameDropThreshold(size_t spatial_idx) const;
size_t SteadyStateSize(int sid, int tid);
const std::unique_ptr<LibvpxInterface> libvpx_;
const absl::optional<std::vector<CpuSpeedExperiment::Config>>
@ -106,6 +110,22 @@ class LibvpxVp8Encoder : public VideoEncoder {
std::vector<vpx_codec_ctx_t> encoders_;
std::vector<vpx_codec_enc_cfg_t> configurations_;
std::vector<vpx_rational_t> downsampling_factors_;
// Variable frame-rate screencast related fields and methods.
const struct VariableFramerateExperiment {
bool enabled = false;
// Framerate is limited to this value in steady state.
float framerate_limit = 5.0;
// This qp or below is considered a steady state.
int steady_state_qp = 15;
// Frames of at least this percentage below ideal for configured bitrate are
// considered in a steady state.
int steady_state_undershoot_percentage = 30;
} variable_framerate_experiment_;
static VariableFramerateExperiment ParseVariableFramerateConfig(
std::string group_name);
FramerateController framerate_controller_;
int num_steady_state_frames_;
};
} // namespace webrtc