media/cast/sender/performance_metrics_overlay.h

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MEDIA_CAST_SENDER_PERFORMANCE_METRICS_OVERLAY_H_
   6 #define MEDIA_CAST_SENDER_PERFORMANCE_METRICS_OVERLAY_H_
   7
   8 // This module provides a display of frame-level performance metrics, rendered
   9 // in the lower-right corner of a VideoFrame.  It looks like this:
  10 //
  11 // +----------------------------------------------------------------+
  12 // |                         @@@@@@@@@@@@@@@@@@@@@@@                |
  13 // |                 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@                |
  14 // |              @@@@@@@@@@@@@@@@@@@@@@@ @@@@@@@@@@@@              |
  15 // |             @@@@@@@@@@@@@                    @@@@              |
  16 // |            @@@@@@@@@@                        @@@@              |
  17 // |           @@@@@  @@@               @@@       @@@@              |
  18 // |           @@@     @    @@@         @@@@      @@@@              |
  19 // |          @@@@          @@@@                  @@@@              |
  20 // |          @@@@                  @@@           @@@               |
  21 // |            @@@@                 @@           @@@               |
  22 // |             @@@@@      @@@            @@@   @@@                |
  23 // |              @@@@@     @@@@@        @@@@   @@@@                |
  24 // |               @@@@@      @@@@@@@@@@@@@    @@@@                 |
  25 // |                @@@@@@                    @@@@      1  45%  75% |
  26 // |                    @@@@@@@@         @@@@@@      22  16.7  4000 |
  27 // |                         @@@@@@@@@@@@@@@@      1280x720 0:15.12 |
  28 // +----------------------------------------------------------------+
  29 //
  30 // Line 1: Reads as, "1 frame ago, the encoder deadline utilization for the
  31 // frame was 45% and the lossy utilization was 75%."  Encoder deadline
  32 // utilization is in terms the amount of real-world time it took to encode the
  33 // frame, divided by the maximum amount of time allowed.  Lossy utilization is
  34 // the amount of "complexity" in the frame's content versus the target encoded
  35 // byte size, where a value over 100% means the frame's content is too complex
  36 // to encode within the target number of bytes.
  37 //
  38 // Line 2: Reads as, "Capture of this frame took 22 ms.  The expected duration
  39 // of this frame is 16.7 ms.  The target bitrate for this frame is 4000 kbps."
  40 //
  41 // Line 3: Contains the frame's resolution and media timestamp in
  42 // minutes:seconds.hundredths format.
  43
  44 namespace media {
  45
  46 class VideoFrame;
  47
  48 namespace cast {
  49
  50 // Renders an overlay of frame-level performance metrics in the lower-right
  51 // corner of the |frame|, as described above.  The verbose logging level for
  52 // video_frame_overlay.cc determines which lines, if any, are rendered: VLOG
  53 // level 1 renders the bottom line only, level 2 renders the bottom and middle
  54 // lines, and level 3 renders all three lines.  So, use the
  55 // --vmodule=performance_metrics_overlay=3 command line argument to turn on
  56 // rendering of the entire overlay.
  57 void MaybeRenderPerformanceMetricsOverlay(int target_bitrate,
  58                                           int frames_ago,
  59                                           double deadline_utilization,
  60                                           double lossy_utilization,
  61                                           VideoFrame* frame);
  62
  63 }  // namespace cast
  64 }  // namespace media
  65
  66 #endif  // MEDIA_CAST_SENDER_PERFORMANCE_METRICS_OVERLAY_H_