Add histogram for percentage of sent frames that are limited in resolution due to quality.

webrtc/video_frame.h

 /*
  *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 163 matching lines @@
   kSkipFrame = 4
 };
 
 // TODO(pbos): Rename EncodedFrame and reformat this class' members.
 class EncodedImage {
  public:
   EncodedImage() : EncodedImage(nullptr, 0, 0) {}
   EncodedImage(uint8_t* buffer, size_t length, size_t size)
       : _buffer(buffer), _length(length), _size(size) {}
 
+  struct AdaptReason {
+    AdaptReason()
+        : quality_available(false),
+          quality_resolution_downscales(0) {}
+
+    bool quality_available;  // True if |quality_resolution_downscales| is

[mflodman, 2015/10/02 09:21:51]

I don't fully understand this comment. Is it true if we might downscale or if it
has been downscaled?

[åsapersson, 2015/10/06 11:26:39]

It is true if we might downscale (the quality scaler is enabled and the number
of downscales (|quality_resolution_downscales|) is provided).

|quality_resolution_downscales| should be ignored if |quality_available| is
false.

[mflodman, 2015/10/07 11:18:58]

Does it make sense to skip the bool and do something like:
quality_resolution_downscales = -1 -> Not available.
quality_resolution_downscales = 0 -> Available but hasn't happened.
quality_resolution_downscales = x -> number of downscales

Or do you prefer keeping the bool?

[åsapersson, 2015/10/09 12:17:07]

Done. Removed bool.

+                             // provided.
+    int quality_resolution_downscales;  // Number of times this frame is down
+                                        // scaled in resolution due to quality.
+  };
   uint32_t _encodedWidth = 0;
   uint32_t _encodedHeight = 0;
   uint32_t _timeStamp = 0;
   // NTP time of the capture time in local timebase in milliseconds.
   int64_t ntp_time_ms_ = 0;
   int64_t capture_time_ms_ = 0;
   // TODO(pbos): Use webrtc::FrameType directly (and remove VideoFrameType).
   VideoFrameType _frameType = kDeltaFrame;
   uint8_t* _buffer;
   size_t _length;
   size_t _size;
   bool _completeFrame = false;
+  AdaptReason adapt_reason_;
 };
 
 }  // namespace webrtc
 #endif  // WEBRTC_VIDEO_FRAME_H_