External VNR speed improvement and more.

webrtc/modules/video_processing/util/noise_estimation.h

Index: webrtc/modules/video_processing/util/noise_estimation.h
diff --git a/webrtc/modules/video_processing/util/noise_estimation.h b/webrtc/modules/video_processing/util/noise_estimation.h
index ca5cc2324fbf4b17294f2b53fb6381256aca80b4..24d44ca4ad15902660c769da54ed3df30468520b 100644
--- a/webrtc/modules/video_processing/util/noise_estimation.h
+++ b/webrtc/modules/video_processing/util/noise_estimation.h
@@ -18,7 +18,6 @@
 
 namespace webrtc {
 
-#define EXPERIMENTAL 0
 #define DISPLAY 0
 
 const int kNoiseThreshold = 200;
@@ -28,11 +27,18 @@ const int kAverageLumaMin = 20;
 const int kAverageLumaMax = 220;
 const int kBlockSelectionVarMax = kNoiseThreshold << 1;
 
+// TODO(jackychen): To test different sampling strategy.
+// Collect noise data every NOISE_SUBSAMPLE_INTERVAL blocks.
+#define NOISE_SUBSAMPLE_INTERVAL 41
+
 class NoiseEstimation {
  public:
   void Init(int width, int height, CpuType cpu_type);
+  // Collect noise data from one qualified block.
   void GetNoise(int mb_index, uint32_t var, uint32_t luma);
+  // Reset the counter for consecutive low-var blocks.
   void ResetConsecLowVar(int mb_index);
+  // Update noise level for current frame.
   void UpdateNoiseLevel();
   // 0: low noise, 1: high noise
   uint8_t GetNoiseLevel();
@@ -42,13 +48,13 @@ class NoiseEstimation {
   int height_;
   int mb_rows_;
   int mb_cols_;
+  int num_noisy_block_;
+  int num_static_block_;
   CpuType cpu_type_;
   uint32_t noise_var_;
   double noise_var_accum_;
-  int num_noisy_block_;
-  int num_static_block_;
   double percent_static_block_;
-  rtc::scoped_ptr<uint32_t[]> consec_low_var_;
+  std::unique_ptr<uint32_t[]> consec_low_var_;
 };
 
 }  // namespace webrtc