Reland of Add a flags field to video timing extension.

webrtc/api/video/video_timing.h

 /*
  *  Copyright (c) 2017 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.
  */
 
 #ifndef WEBRTC_API_VIDEO_VIDEO_TIMING_H_
 #define WEBRTC_API_VIDEO_VIDEO_TIMING_H_
 
 #include <stdint.h>
 
+#include <limits>
 #include <string>
 
 #include "webrtc/rtc_base/checks.h"
 #include "webrtc/rtc_base/safe_conversions.h"
 
 namespace webrtc {
 
+enum TimingFrameFlags : uint8_t {
+  kDefault = 0,                // No flags set (used by old protocol)
+  kTriggeredByTimer = 1 << 0,  // Frame marked for tracing by periodic timer.
+  kTriggeredBySize = 1 << 1,   // Frame marked for tracing due to size.
+  kInvalid = std::numeric_limits<uint8_t>::max()  // Invalid, ignore!
+};
+
 // Video timing timestamps in ms counted from capture_time_ms of a frame.
 // This structure represents data sent in video-timing RTP header extension.
 struct VideoSendTiming {
-  static const uint8_t kEncodeStartDeltaIdx = 0;
-  static const uint8_t kEncodeFinishDeltaIdx = 1;
-  static const uint8_t kPacketizationFinishDeltaIdx = 2;
-  static const uint8_t kPacerExitDeltaIdx = 3;
-  static const uint8_t kNetworkTimestampDeltaIdx = 4;
-  static const uint8_t kNetwork2TimestampDeltaIdx = 5;
+  // Offsets of the fields in the RTP header extension, counting from the first
+  // byte after the one-byte header.
+  static constexpr uint8_t kFlagsOffset = 0;
+  static constexpr uint8_t kEncodeStartDeltaOffset = 1;
+  static constexpr uint8_t kEncodeFinishDeltaOffset = 3;
+  static constexpr uint8_t kPacketizationFinishDeltaOffset = 5;
+  static constexpr uint8_t kPacerExitDeltaOffset = 7;
+  static constexpr uint8_t kNetworkTimestampDeltaOffset = 9;
+  static constexpr uint8_t kNetwork2TimestampDeltaOffset = 11;
 
   // Returns |time_ms - base_ms| capped at max 16-bit value.
   // Used to fill this data structure as per
   // https://webrtc.org/experiments/rtp-hdrext/video-timing/ extension stores
   // 16-bit deltas of timestamps from packet capture time.
   static uint16_t GetDeltaCappedMs(int64_t base_ms, int64_t time_ms) {
     RTC_DCHECK_GE(time_ms, base_ms);
     return rtc::saturated_cast<uint16_t>(time_ms - base_ms);
   }
 
   uint16_t encode_start_delta_ms;
   uint16_t encode_finish_delta_ms;
   uint16_t packetization_finish_delta_ms;
   uint16_t pacer_exit_delta_ms;
   uint16_t network_timstamp_delta_ms;
   uint16_t network2_timstamp_delta_ms;
-  bool is_timing_frame;
+  uint8_t flags;
 };
 
 // Used to report precise timings of a 'timing frames'. Contains all important
 // timestamps for a lifetime of that specific frame. Reported as a string via
 // GetStats(). Only frame which took the longest between two GetStats calls is
 // reported.
 struct TimingFrameInfo {
   TimingFrameInfo();
 
   // Returns end-to-end delay of a frame, if sender and receiver timestamps are
   // synchronized, -1 otherwise.
   int64_t EndToEndDelay() const;
 
   // Returns true if current frame took longer to process than |other| frame.
   // If other frame's clocks are not synchronized, current frame is always
   // preferred.
   bool IsLongerThan(const TimingFrameInfo& other) const;
 
+  // Returns true if flags are set to indicate this frame was marked for tracing
+  // due to the size being outside some limit.
+  bool IsOutlier() const;
+
+  // Returns true if flags are set to indicate this frame was marked fro tracing
+  // due to cyclic timer.
+  bool IsTimerTriggered() const;
+
+  // Returns true if the timing data is marked as invalid, in which case it
+  // should be ignored.
+  bool IsInvalid() const;
+
   std::string ToString() const;
 
   uint32_t rtp_timestamp;  // Identifier of a frame.
   // All timestamps below are in local monotonous clock of a receiver.
   // If sender clock is not yet estimated, sender timestamps
   // (capture_time_ms ... pacer_exit_ms) are negative values, still
   // relatively correct.
   int64_t capture_time_ms;          // Captrue time of a frame.
   int64_t encode_start_ms;          // Encode start time.
   int64_t encode_finish_ms;         // Encode completion time.
   int64_t packetization_finish_ms;  // Time when frame was passed to pacer.
   int64_t pacer_exit_ms;  // Time when last packet was pushed out of pacer.
   // Two in-network RTP processor timestamps: meaning is application specific.
   int64_t network_timestamp_ms;
   int64_t network2_timestamp_ms;
   int64_t receive_start_ms;   // First received packet time.
   int64_t receive_finish_ms;  // Last received packet time.
   int64_t decode_start_ms;    // Decode start time.
   int64_t decode_finish_ms;   // Decode completion time.
   int64_t render_time_ms;     // Proposed render time to insure smooth playback.
+
+  uint8_t flags;  // Flags indicating validity and/or why tracing was triggered.
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_API_VIDEO_VIDEO_TIMING_H_