External VNR speed improvement and more.

webrtc/modules/video_processing/frame_preprocessor.h

Index: webrtc/modules/video_processing/frame_preprocessor.h
diff --git a/webrtc/modules/video_processing/frame_preprocessor.h b/webrtc/modules/video_processing/frame_preprocessor.h
index c35dd0d7affe5a8b23c837f697606a1f1c744dc6..270fbc2fc9e9a713ab39f8bfebda8137f3da8ecc 100644
--- a/webrtc/modules/video_processing/frame_preprocessor.h
+++ b/webrtc/modules/video_processing/frame_preprocessor.h
@@ -70,14 +70,14 @@ class VPMFramePreprocessor {
   enum { kSkipFrameCA = 2 };
 
   VideoContentMetrics* content_metrics_;
-  VideoFrame denoised_frame_;
-  VideoFrame denoised_frame_prev_;
+  VideoFrame denoised_frame_[2];
   VideoFrame resampled_frame_;
   VPMSpatialResampler* spatial_resampler_;
   VPMContentAnalysis* ca_;
   VPMVideoDecimator* vd_;
   std::unique_ptr<VideoDenoiser> denoiser_;
   bool enable_ca_;
+  uint8_t denoised_frame_toggle_;
   uint32_t frame_cnt_;
 };