1 /*
2  *  Copyright (c) 2013 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_VIDEO_ENGINE_OVERUSE_FRAME_DETECTOR_H_
12 #define WEBRTC_VIDEO_ENGINE_OVERUSE_FRAME_DETECTOR_H_
13 
14 #include "webrtc/base/constructormagic.h"
15 #include "webrtc/base/criticalsection.h"
16 #include "webrtc/base/scoped_ptr.h"
17 #include "webrtc/base/exp_filter.h"
18 #include "webrtc/base/thread_annotations.h"
19 #include "webrtc/base/thread_checker.h"
20 #include "webrtc/modules/interface/module.h"
21 #include "webrtc/video_engine/include/vie_base.h"
22 
23 namespace webrtc {
24 
25 class Clock;
26 class CpuOveruseObserver;
27 
28 // TODO(pbos): Move this somewhere appropriate.
29 class Statistics {
30  public:
31   Statistics();
32 
33   void AddSample(float sample_ms);
34   void Reset();
35   void SetOptions(const CpuOveruseOptions& options);
36 
37   float Mean() const;
38   float StdDev() const;
39   uint64_t Count() const;
40 
41  private:
42   float InitialMean() const;
43   float InitialVariance() const;
44 
45   float sum_;
46   uint64_t count_;
47   CpuOveruseOptions options_;
48   rtc::scoped_ptr<rtc::ExpFilter> filtered_samples_;
49   rtc::scoped_ptr<rtc::ExpFilter> filtered_variance_;
50 };
51 
52 // Use to detect system overuse based on jitter in incoming frames.
53 class OveruseFrameDetector : public Module {
54  public:
55   OveruseFrameDetector(Clock* clock,
56                        CpuOveruseMetricsObserver* metrics_observer);
57   ~OveruseFrameDetector();
58 
59   // Registers an observer receiving overuse and underuse callbacks. Set
60   // 'observer' to NULL to disable callbacks.
61   void SetObserver(CpuOveruseObserver* observer);
62 
63   // Sets options for overuse detection.
64   void SetOptions(const CpuOveruseOptions& options);
65 
66   // Called for each captured frame.
67   void FrameCaptured(int width, int height, int64_t capture_time_ms);
68 
69   // Called when the processing of a captured frame is started.
70   void FrameProcessingStarted();
71 
72   // Called for each encoded frame.
73   void FrameEncoded(int encode_time_ms);
74 
75   // Called for each sent frame.
76   void FrameSent(int64_t capture_time_ms);
77 
78   // Only public for testing.
79   int CaptureQueueDelayMsPerS() const;
80   int LastProcessingTimeMs() const;
81   int FramesInQueue() const;
82 
83   // Implements Module.
84   int64_t TimeUntilNextProcess() override;
85   int32_t Process() override;
86 
87  private:
88   class EncodeTimeAvg;
89   class SendProcessingUsage;
90   class CaptureQueueDelay;
91   class FrameQueue;
92 
93   void UpdateCpuOveruseMetrics() EXCLUSIVE_LOCKS_REQUIRED(crit_);
94 
95   // TODO(asapersson): This method is only used on one thread, so it shouldn't
96   // need a guard.
97   void AddProcessingTime(int elapsed_ms) EXCLUSIVE_LOCKS_REQUIRED(crit_);
98 
99   // TODO(asapersson): This method is always called on the processing thread.
100   // If locking is required, consider doing that locking inside the
101   // implementation and reduce scope as much as possible.  We should also
102   // see if we can avoid calling out to other methods while holding the lock.
103   bool IsOverusing() EXCLUSIVE_LOCKS_REQUIRED(crit_);
104   bool IsUnderusing(int64_t time_now) EXCLUSIVE_LOCKS_REQUIRED(crit_);
105 
106   bool FrameTimeoutDetected(int64_t now) const EXCLUSIVE_LOCKS_REQUIRED(crit_);
107   bool FrameSizeChanged(int num_pixels) const EXCLUSIVE_LOCKS_REQUIRED(crit_);
108 
109   void ResetAll(int num_pixels) EXCLUSIVE_LOCKS_REQUIRED(crit_);
110 
111   // Protecting all members except const and those that are only accessed on the
112   // processing thread.
113   // TODO(asapersson): See if we can reduce locking.  As is, video frame
114   // processing contends with reading stats and the processing thread.
115   mutable rtc::CriticalSection crit_;
116 
117   // Observer getting overuse reports.
118   CpuOveruseObserver* observer_ GUARDED_BY(crit_);
119 
120   CpuOveruseOptions options_ GUARDED_BY(crit_);
121 
122   // Stats metrics.
123   CpuOveruseMetricsObserver* const metrics_observer_;
124   CpuOveruseMetrics metrics_ GUARDED_BY(crit_);
125 
126   Clock* const clock_;
127   int64_t next_process_time_;  // Only accessed on the processing thread.
128   int64_t num_process_times_ GUARDED_BY(crit_);
129 
130   Statistics capture_deltas_ GUARDED_BY(crit_);
131   int64_t last_capture_time_ GUARDED_BY(crit_);
132 
133   // These six members are only accessed on the processing thread.
134   int64_t last_overuse_time_;
135   int checks_above_threshold_;
136   int num_overuse_detections_;
137 
138   int64_t last_rampup_time_;
139   bool in_quick_rampup_;
140   int current_rampup_delay_ms_;
141 
142   // Number of pixels of last captured frame.
143   int num_pixels_ GUARDED_BY(crit_);
144 
145   int64_t last_encode_sample_ms_;  // Only accessed by one thread.
146 
147   // TODO(asapersson): Can these be regular members (avoid separate heap
148   // allocs)?
149   const rtc::scoped_ptr<EncodeTimeAvg> encode_time_ GUARDED_BY(crit_);
150   const rtc::scoped_ptr<SendProcessingUsage> usage_ GUARDED_BY(crit_);
151   const rtc::scoped_ptr<FrameQueue> frame_queue_ GUARDED_BY(crit_);
152 
153   int64_t last_sample_time_ms_;  // Only accessed by one thread.
154 
155   const rtc::scoped_ptr<CaptureQueueDelay> capture_queue_delay_
156       GUARDED_BY(crit_);
157 
158   rtc::ThreadChecker processing_thread_;
159 
160   DISALLOW_COPY_AND_ASSIGN(OveruseFrameDetector);
161 };
162 
163 }  // namespace webrtc
164 
165 #endif  // WEBRTC_VIDEO_ENGINE_OVERUSE_FRAME_DETECTOR_H_
166