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 #include "base/time/time.h" 9 #include "media/base/video_frame.h" 10 11 // This module provides a display of frame-level performance metrics, rendered 12 // in the lower-right corner of a VideoFrame. It looks like this: 13 // 14 // +---------------------------------------------------------------------+ 15 // | @@@@@@@@@@@@@@@@@@@@@@@ | 16 // | @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | 17 // | @@@@@@@@@@@@@@@@@@@@@@@ @@@@@@@@@@@@ | 18 // | @@@@@@@@@@@@@ @@@@ | 19 // | @@@@@@@@@@ @@@@ | 20 // | @@@@@ @@@ @@@ @@@@ | 21 // | @@@ @ @@@ @@@@ @@@@ | 22 // | @@@@ @@@@ @@@@ | 23 // | @@@@ @@@ @@@ | 24 // | @@@@ @@ @@@ | 25 // | @@@@@ @@@ @@@ @@@ | 26 // | @@@@@ @@@@@ @@@@ @@@@ | 27 // | @@@@@ @@@@@@@@@@@@@ @@@@ | 28 // | @@@@@@ @@@@ 1 45% 75% | 29 // | @@@@@@@@ @@@@@@ 22 400. 4000 | 30 // | @@@@@@@@@@@@@@@@ 16.7 1280x720 0:15.12 | 31 // +---------------------------------------------------------------------+ 32 // 33 // Line 1: Reads as, "1 frame ago, the encoder utilization for the frame was 45% 34 // and the lossy utilization was 75%." For CPU-bound encoders, encoder 35 // utilization is usually measured as the amount of real-world time it took to 36 // encode the frame, divided by the maximum amount of time allowed. Lossy 37 // utilization is the amount of "complexity" in the frame's content versus the 38 // target encoded byte size, where a value over 100% means the frame's content 39 // is too complex to encode within the target number of bytes. 40 // 41 // Line 2: Reads as, "Capture of this frame took 22 ms. The current target 42 // playout delay is 400 ms and low-latency adjustment mode is not active. The 43 // target bitrate for this frame is 4000 kbps." If there were an exclamation 44 // mark (!) after the playout delay number instead of a period (.), it would 45 // indicate low-latency adjustment mode is active. See VideoSender for more 46 // details. 47 // 48 // Line 3: Contains the frame's duration (16.7 milliseconds), resolution, and 49 // media timestamp in minutes:seconds.hundredths format. 50 51 namespace media { 52 namespace cast { 53 54 // If the user has requested VideoFrames have a performance metrics overlay 55 // rendered on them, this function copies the |source| frame and then renders an 56 // overlay on the copy. Frame-level performance metrics will be rendered in the 57 // lower-right corner of the frame, as described in the module-level comments 58 // above. 59 // 60 // The verbose logging level for video_frame_overlay.cc determines which lines, 61 // if any, are rendered: no VLOG level does nothing, level 1 renders the bottom 62 // line only, level 2 renders the bottom and middle lines, and level 3 renders 63 // all three lines. So, use the --vmodule=performance_metrics_overlay=3 command 64 // line argument to turn on rendering of the entire overlay. 65 // 66 // Note: If |source| is an unsupported format, or no pixels need to be modified, 67 // this function will just return |source|. 68 scoped_refptr<VideoFrame> MaybeRenderPerformanceMetricsOverlay( 69 base::TimeDelta target_playout_delay, 70 bool in_low_latency_mode, 71 int target_bitrate, 72 int frames_ago, 73 double encoder_utilization, 74 double lossy_utilization, 75 scoped_refptr<VideoFrame> source); 76 77 } // namespace cast 78 } // namespace media 79 80 #endif // MEDIA_CAST_SENDER_PERFORMANCE_METRICS_OVERLAY_H_ 81