git.sesse.net Git - nageru/blob - print_latency.cpp

   1 #include "print_latency.h"
   2
   3 #include "flags.h"
   4
   5 #include <stdio.h>
   6 #include <chrono>
   7 #include <string>
   8
   9 using namespace std;
  10 using namespace std::chrono;
  11
  12 ReceivedTimestamps find_received_timestamp(const vector<RefCountedFrame> &input_frames)
  13 {
  14         // Find min and max timestamp of all input frames that have a timestamp.
  15         steady_clock::time_point min_ts = steady_clock::time_point::max(), max_ts = steady_clock::time_point::min();
  16         for (const RefCountedFrame &input_frame : input_frames) {
  17                 if (input_frame && input_frame->received_timestamp > steady_clock::time_point::min()) {
  18                         min_ts = min(min_ts, input_frame->received_timestamp);
  19                         max_ts = max(max_ts, input_frame->received_timestamp);
  20                 }
  21         }
  22         return { min_ts, max_ts };
  23 }
  24
  25 void print_latency(const string &header, const ReceivedTimestamps &received_ts, bool is_b_frame, int *frameno)
  26 {
  27         if (received_ts.max_ts == steady_clock::time_point::min())
  28                 return;
  29
  30         // 101 is chosen so that it's prime, which is unlikely to get the same frame type every time.
  31         if (global_flags.print_video_latency && (++*frameno % 101) == 0) {
  32                 const steady_clock::time_point now = steady_clock::now();
  33                 printf("%-60s %4.0f ms (lowest-latency input), %4.0f ms (highest-latency input)",
  34                         header.c_str(),
  35                         1e3 * std::chrono::duration<double>(now - received_ts.max_ts).count(),
  36                         1e3 * std::chrono::duration<double>(now - received_ts.min_ts).count());
  37
  38                 if (is_b_frame) {
  39                         printf("  [on B-frame; potential extra latency]\n");
  40                 } else {
  41                         printf("\n");
  42                 }
  43         }
  44 }