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      1 /*
      2  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
      3  *
      4  *  Use of this source code is governed by a BSD-style license
      5  *  that can be found in the LICENSE file in the root of the source
      6  *  tree. An additional intellectual property rights grant can be found
      7  *  in the file PATENTS.  All contributing project authors may
      8  *  be found in the AUTHORS file in the root of the source tree.
      9  */
     10 
     11 #ifndef WEBRTC_MODULES_VIDEO_CODING_MEDIA_OPTIMIZATION_H_
     12 #define WEBRTC_MODULES_VIDEO_CODING_MEDIA_OPTIMIZATION_H_
     13 
     14 #include <list>
     15 
     16 #include "webrtc/base/scoped_ptr.h"
     17 #include "webrtc/modules/include/module_common_types.h"
     18 #include "webrtc/modules/video_coding/include/video_coding.h"
     19 #include "webrtc/modules/video_coding/media_opt_util.h"
     20 #include "webrtc/modules/video_coding/qm_select.h"
     21 #include "webrtc/system_wrappers/include/critical_section_wrapper.h"
     22 
     23 namespace webrtc {
     24 
     25 // Forward declarations.
     26 class Clock;
     27 class FrameDropper;
     28 class VCMContentMetricsProcessing;
     29 
     30 namespace media_optimization {
     31 
     32 class MediaOptimization {
     33  public:
     34   explicit MediaOptimization(Clock* clock);
     35   ~MediaOptimization();
     36 
     37   // TODO(andresp): Can Reset and SetEncodingData be done at construction time
     38   // only?
     39   void Reset();
     40 
     41   // Informs media optimization of initial encoding state.
     42   void SetEncodingData(VideoCodecType send_codec_type,
     43                        int32_t max_bit_rate,
     44                        uint32_t bit_rate,
     45                        uint16_t width,
     46                        uint16_t height,
     47                        uint32_t frame_rate,
     48                        int num_temporal_layers,
     49                        int32_t mtu);
     50 
     51   // Sets target rates for the encoder given the channel parameters.
     52   // Inputs:  target bitrate - the encoder target bitrate in bits/s.
     53   //          fraction_lost - packet loss rate in % in the network.
     54   //          round_trip_time_ms - round trip time in milliseconds.
     55   //          min_bit_rate - the bit rate of the end-point with lowest rate.
     56   //          max_bit_rate - the bit rate of the end-point with highest rate.
     57   // TODO(andresp): Find if the callbacks can be triggered only after releasing
     58   // an internal critical section.
     59   uint32_t SetTargetRates(uint32_t target_bitrate,
     60                           uint8_t fraction_lost,
     61                           int64_t round_trip_time_ms,
     62                           VCMProtectionCallback* protection_callback,
     63                           VCMQMSettingsCallback* qmsettings_callback);
     64 
     65   void SetProtectionMethod(VCMProtectionMethodEnum method);
     66   void EnableQM(bool enable);
     67   void EnableFrameDropper(bool enable);
     68 
     69   // Lets the sender suspend video when the rate drops below
     70   // |threshold_bps|, and turns back on when the rate goes back up above
     71   // |threshold_bps| + |window_bps|.
     72   void SuspendBelowMinBitrate(int threshold_bps, int window_bps);
     73   bool IsVideoSuspended() const;
     74 
     75   bool DropFrame();
     76 
     77   void UpdateContentData(const VideoContentMetrics* content_metrics);
     78 
     79   // Informs Media Optimization of encoded output.
     80   int32_t UpdateWithEncodedData(const EncodedImage& encoded_image);
     81 
     82   // InputFrameRate 0 = no frame rate estimate available.
     83   uint32_t InputFrameRate();
     84   uint32_t SentFrameRate();
     85   uint32_t SentBitRate();
     86 
     87  private:
     88   enum { kFrameCountHistorySize = 90 };
     89   enum { kFrameHistoryWinMs = 2000 };
     90   enum { kBitrateAverageWinMs = 1000 };
     91 
     92   struct EncodedFrameSample;
     93   typedef std::list<EncodedFrameSample> FrameSampleList;
     94 
     95   void UpdateIncomingFrameRate() EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
     96   void PurgeOldFrameSamples(int64_t now_ms)
     97       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
     98   void UpdateSentBitrate(int64_t now_ms) EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
     99   void UpdateSentFramerate() EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
    100 
    101   // Computes new Quality Mode.
    102   int32_t SelectQuality(VCMQMSettingsCallback* qmsettings_callback)
    103       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
    104 
    105   // Verifies if QM settings differ from default, i.e. if an update is required.
    106   // Computes actual values, as will be sent to the encoder.
    107   bool QMUpdate(VCMResolutionScale* qm,
    108                 VCMQMSettingsCallback* qmsettings_callback)
    109       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
    110 
    111   // Checks if we should make a QM change. Return true if yes, false otherwise.
    112   bool CheckStatusForQMchange() EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
    113 
    114   void ProcessIncomingFrameRate(int64_t now)
    115       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
    116 
    117   // Checks conditions for suspending the video. The method compares
    118   // |video_target_bitrate_| with the threshold values for suspension, and
    119   // changes the state of |video_suspended_| accordingly.
    120   void CheckSuspendConditions() EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
    121 
    122   void SetEncodingDataInternal(VideoCodecType send_codec_type,
    123                                int32_t max_bit_rate,
    124                                uint32_t frame_rate,
    125                                uint32_t bit_rate,
    126                                uint16_t width,
    127                                uint16_t height,
    128                                int num_temporal_layers,
    129                                int32_t mtu)
    130       EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
    131 
    132   uint32_t InputFrameRateInternal() EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
    133 
    134   uint32_t SentFrameRateInternal() EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
    135 
    136   // Protect all members.
    137   rtc::scoped_ptr<CriticalSectionWrapper> crit_sect_;
    138 
    139   Clock* clock_ GUARDED_BY(crit_sect_);
    140   int32_t max_bit_rate_ GUARDED_BY(crit_sect_);
    141   VideoCodecType send_codec_type_ GUARDED_BY(crit_sect_);
    142   uint16_t codec_width_ GUARDED_BY(crit_sect_);
    143   uint16_t codec_height_ GUARDED_BY(crit_sect_);
    144   float user_frame_rate_ GUARDED_BY(crit_sect_);
    145   rtc::scoped_ptr<FrameDropper> frame_dropper_ GUARDED_BY(crit_sect_);
    146   rtc::scoped_ptr<VCMLossProtectionLogic> loss_prot_logic_
    147       GUARDED_BY(crit_sect_);
    148   uint8_t fraction_lost_ GUARDED_BY(crit_sect_);
    149   uint32_t send_statistics_[4] GUARDED_BY(crit_sect_);
    150   uint32_t send_statistics_zero_encode_ GUARDED_BY(crit_sect_);
    151   int32_t max_payload_size_ GUARDED_BY(crit_sect_);
    152   int video_target_bitrate_ GUARDED_BY(crit_sect_);
    153   float incoming_frame_rate_ GUARDED_BY(crit_sect_);
    154   int64_t incoming_frame_times_[kFrameCountHistorySize] GUARDED_BY(crit_sect_);
    155   bool enable_qm_ GUARDED_BY(crit_sect_);
    156   std::list<EncodedFrameSample> encoded_frame_samples_ GUARDED_BY(crit_sect_);
    157   uint32_t avg_sent_bit_rate_bps_ GUARDED_BY(crit_sect_);
    158   uint32_t avg_sent_framerate_ GUARDED_BY(crit_sect_);
    159   uint32_t key_frame_cnt_ GUARDED_BY(crit_sect_);
    160   uint32_t delta_frame_cnt_ GUARDED_BY(crit_sect_);
    161   rtc::scoped_ptr<VCMContentMetricsProcessing> content_ GUARDED_BY(crit_sect_);
    162   rtc::scoped_ptr<VCMQmResolution> qm_resolution_ GUARDED_BY(crit_sect_);
    163   int64_t last_qm_update_time_ GUARDED_BY(crit_sect_);
    164   int64_t last_change_time_ GUARDED_BY(crit_sect_);  // Content/user triggered.
    165   int num_layers_ GUARDED_BY(crit_sect_);
    166   bool suspension_enabled_ GUARDED_BY(crit_sect_);
    167   bool video_suspended_ GUARDED_BY(crit_sect_);
    168   int suspension_threshold_bps_ GUARDED_BY(crit_sect_);
    169   int suspension_window_bps_ GUARDED_BY(crit_sect_);
    170 };
    171 }  // namespace media_optimization
    172 }  // namespace webrtc
    173 
    174 #endif  // WEBRTC_MODULES_VIDEO_CODING_MEDIA_OPTIMIZATION_H_
    175