- Reset capture deltas at resolution change.
- Applied smoothing of capture jitter.
- Adjusted thresholds.

R=stefan@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/2070005

git-svn-id: http://webrtc.googlecode.com/svn/trunk@4817 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/video_engine/overuse_frame_detector.h b/webrtc/video_engine/overuse_frame_detector.h
index 00d3b19..4717a60 100644
--- a/webrtc/video_engine/overuse_frame_detector.h
+++ b/webrtc/video_engine/overuse_frame_detector.h
@@ -18,32 +18,50 @@
 namespace webrtc {
 
 class Clock;
-class CriticalSectionWrapper;
 class CpuOveruseObserver;
+class CriticalSectionWrapper;
+class VCMExpFilter;
 
-// TODO(pbos): Move this somewhere appropriate
+// Limits on standard deviation for under/overuse.
+#ifdef WEBRTC_LINUX
+const float kOveruseStdDevMs = 15.0f;
+const float kNormalUseStdDevMs = 7.0f;
+#elif WEBRTC_MAC
+const float kOveruseStdDevMs = 22.0f;
+const float kNormalUseStdDevMs = 12.0f;
+#else
+const float kOveruseStdDevMs = 17.0f;
+const float kNormalUseStdDevMs = 10.0f;
+#endif
+
+// TODO(pbos): Move this somewhere appropriate.
 class Statistics {
  public:
   Statistics();
 
-  void AddSample(double sample);
+  void AddSample(float sample_ms);
   void Reset();
 
-  double Mean() const;
-  double Variance() const;
-  double StdDev() const;
-  uint64_t Samples() const;
+  float Mean() const;
+  float StdDev() const;
+  uint64_t Count() const;
 
  private:
-  double sum_;
-  double sum_squared_;
+  float InitialMean() const;
+  float InitialVariance() const;
+
+  float sum_;
   uint64_t count_;
+  scoped_ptr<VCMExpFilter> filtered_samples_;
+  scoped_ptr<VCMExpFilter> filtered_variance_;
 };
 
 // Use to detect system overuse based on jitter in incoming frames.
 class OveruseFrameDetector : public Module {
  public:
-  explicit OveruseFrameDetector(Clock* clock);
+  explicit OveruseFrameDetector(Clock* clock,
+                                float normaluse_stddev_ms,
+                                float overuse_stddev_ms);
   ~OveruseFrameDetector();
 
   // Registers an observer receiving overuse and underuse callbacks. Set
@@ -51,7 +69,7 @@
   void SetObserver(CpuOveruseObserver* observer);
 
   // Called for each captured frame.
-  void FrameCaptured();
+  void FrameCaptured(int width, int height);
 
   // Implements Module.
   virtual int32_t TimeUntilNextProcess() OVERRIDE;
@@ -64,6 +82,10 @@
   // Protecting all members.
   scoped_ptr<CriticalSectionWrapper> crit_;
 
+  // Limits on standard deviation for under/overuse.
+  const float normaluse_stddev_ms_;
+  const float overuse_stddev_ms_;
+
   // Observer getting overuse reports.
   CpuOveruseObserver* observer_;
 
@@ -80,6 +102,9 @@
   bool in_quick_rampup_;
   int current_rampup_delay_ms_;
 
+  // Number of pixels of last captured frame.
+  int num_pixels_;
+
   DISALLOW_COPY_AND_ASSIGN(OveruseFrameDetector);
 };