zqz/platform-external-webrtc
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

In screenshare mode, suppress VP8 bitrate overshoot and increase quality

Browse Source 
This change includes several improvements:

* VP8 configured with new rate control
* Detection of frame dropping, with qp bump for next frame
* Increased target and TL0 bitrates
* Reworked rate control (TL allocation) in screenshare_layers

A note on performance: PSNR and SSIM is expected to get slightly worse with this cl. Frame drops and delays should however improve.

BUG=4171
R=pbos@webrtc.org, stefan@webrtc.org

Review URL: https://codereview.webrtc.org/1193513006.

Cr-Commit-Position: refs/heads/master@{#9495}
This commit is contained in:
Erik Språng
2015-06-24 11:24:44 +02:00
parent 7ab5f801dd
commit 2c4c914819
16 changed files with 610 additions and 294 deletions
Download Patch File Download Diff File Expand all files Collapse all files

71
webrtc/modules/video_coding/codecs/vp8/screenshare_layers.h
View File

@ -13,6 +13,7 @@
#include "vpx/vpx_encoder.h"
#include "webrtc/base/timeutils.h"
#include "webrtc/modules/video_coding/codecs/vp8/temporal_layers.h"
#include "webrtc/modules/video_coding/utility/include/frame_dropper.h"
#include "webrtc/typedefs.h"
@ -25,43 +26,73 @@ class ScreenshareLayers : public TemporalLayers {
public:
static const double kMaxTL0FpsReduction;
static const double kAcceptableTargetOvershoot;
static const int kTl0Flags;
static const int kTl1Flags;
static const int kTl1SyncFlags;
ScreenshareLayers(int num_temporal_layers,
uint8_t initial_tl0_pic_idx,
FrameDropper* tl0_frame_dropper,
FrameDropper* tl1_frame_dropper);
ScreenshareLayers(int num_temporal_layers, uint8_t initial_tl0_pic_idx);
virtual ~ScreenshareLayers() {}
// Returns the recommended VP8 encode flags needed. May refresh the decoder
// and/or update the reference buffers.
virtual int EncodeFlags(uint32_t timestamp);
int EncodeFlags(uint32_t timestamp) override;
virtual bool ConfigureBitrates(int bitrate_kbit,
int max_bitrate_kbit,
int framerate,
vpx_codec_enc_cfg_t* cfg);
bool ConfigureBitrates(int bitrate_kbps,
int max_bitrate_kbps,
int framerate,
vpx_codec_enc_cfg_t* cfg) override;
virtual void PopulateCodecSpecific(bool base_layer_sync,
CodecSpecificInfoVP8 *vp8_info,
uint32_t timestamp);
void PopulateCodecSpecific(bool base_layer_sync,
CodecSpecificInfoVP8* vp8_info,
uint32_t timestamp) override;
virtual void FrameEncoded(unsigned int size, uint32_t timestamp);
void FrameEncoded(unsigned int size, uint32_t timestamp, int qp) override;
virtual int CurrentLayerId() const;
int CurrentLayerId() const override;
// Allows the layers adapter to update the encoder configuration prior to a
// frame being encoded. Return true if the configuration should be updated
// and false if now change is needed.
bool UpdateConfiguration(vpx_codec_enc_cfg_t* cfg) override;
private:
void CalculateFramerate(uint32_t timestamp);
bool TimeToSync(uint32_t timestamp) const;
bool TimeToSync(int64_t timestamp) const;
FrameDropper* tl0_frame_dropper_;
FrameDropper* tl1_frame_dropper_;
int number_of_temporal_layers_;
bool last_base_layer_sync_;
uint8_t tl0_pic_idx_;
int active_layer_;
std::list<uint32_t> timestamp_list_;
int framerate_;
int64_t last_timestamp_;
int64_t last_sync_timestamp_;
rtc::TimestampWrapAroundHandler time_wrap_handler_;
int min_qp_;
int max_qp_;
uint32_t max_debt_bytes_;
int frame_rate_;
static const int kMaxNumTemporalLayers = 2;
struct TemporalLayer {
TemporalLayer()
: state(State::kNormal),
enhanced_max_qp(-1),
last_qp(-1),
debt_bytes_(0),
target_rate_kbps_(0) {}
enum class State {
kNormal,
kDropped,
kReencoded,
kQualityBoost,
} state;
int enhanced_max_qp;
int last_qp;
uint32_t debt_bytes_;
uint32_t target_rate_kbps_;
void UpdateDebt(int64_t delta_ms);
} layers_[kMaxNumTemporalLayers];
};
} // namespace webrtc