Add framerate to VideoSinkWants and ability to signal on overuse

webrtc/video/vie_encoder.h

Index: webrtc/video/vie_encoder.h
diff --git a/webrtc/video/vie_encoder.h b/webrtc/video/vie_encoder.h
index c0b80baadd6e948c918b8f75fb704b5b77b4e2b4..b6674e11b62c1d9a04a069aed75f54c2eb81b357 100644
--- a/webrtc/video/vie_encoder.h
+++ b/webrtc/video/vie_encoder.h
@@ -11,6 +11,7 @@
 #ifndef WEBRTC_VIDEO_VIE_ENCODER_H_
 #define WEBRTC_VIDEO_VIE_ENCODER_H_
 
+#include <map>
 #include <memory>
 #include <string>
 #include <vector>
@@ -216,8 +217,10 @@ class ViEEncoder : public rtc::VideoSinkInterface<VideoFrame>,
   uint64_t picture_id_rpsi_ ACCESS_ON(&encoder_queue_);
   Clock* const clock_;
   // Counters used for deciding if the video resolution is currently
-  // restricted, and if so, why.
-  std::vector<int> scale_counter_ ACCESS_ON(&encoder_queue_);
+  // restricted, and if so, why, on a per degradation preference basis.
+  // TODO(sprang): Replace this with a state holding a relative overuse measure
+  // instead, that can be translated into suitable down-scale or fps limit.
+  std::map<size_t, std::vector<int>> scale_counter_ ACCESS_ON(&encoder_queue_);

[kthelgason, 2017/02/27 14:02:39]

Why not have this a map from DegradationPreference -> std::vector? 
It's clearer and saves on a cast.

Can we make the container const since the number of entries is known at
compile-time?

[sprang_webrtc, 2017/02/28 08:46:28]

Hm, when I tried this I kept getting giant obscure error messages so I switched
to ints, but now it seems to work fine for some reason. Wonder what I did...

The container itself can't be const as then we can't mutate the the vectors
within. Or am I missing something?

   // Set depending on degradation preferences
   VideoSendStream::DegradationPreference degradation_preference_
       ACCESS_ON(&encoder_queue_);
@@ -225,6 +228,8 @@ class ViEEncoder : public rtc::VideoSinkInterface<VideoFrame>,
   struct AdaptationRequest {
     // The pixel count produced by the source at the time of the adaptation.
     int input_pixel_count_;
+    // Framerate received from the source at the time of the adaptation.
+    int framerate_fps_;
     // Indicates if request was to adapt up or down.
     enum class Mode { kAdaptUp, kAdaptDown } mode_;
   };