Fix calculation for when to send a keepalive image. Possible fixes #4101

src/zm_eventstream.cpp

@@ -940,12 +940,13 @@ void EventStream::runStream() {
  Microseconds delta = Microseconds(0);
 
  while (!zm_terminate) {
- start = std::chrono::steady_clock::now();
+ now = start = std::chrono::steady_clock::now();
 
  {
  std::scoped_lock lck{mutex};
 
  send_frame = false;
+ TimePoint::duration time_since_last_send = now - last_frame_sent;
 
  if (!paused) {
  // Figure out if we should send this frame
@@ -964,16 +965,22 @@ void EventStream::runStream() {
  send_frame = true;
  } else if (!send_frame) {
  // We are paused, not stepping and doing nothing, meaning that comms didn't set send_frame to true
- if (now - last_frame_sent > MAX_STREAM_DELAY) {
+ if (time_since_last_send > MAX_STREAM_DELAY) {
  // Send keepalive
  Debug(2, "Sending keepalive frame");
  send_frame = true;
+ } else {
+ Debug(4, "Not Sending keepalive frame now %.2f - %.2f last = %.2f > Max %.2f",
+ FPSeconds(now.time_since_epoch()).count(),
+ FPSeconds(last_frame_sent.time_since_epoch()).count(),
+ FPSeconds(time_since_last_send).count(),
+ FPSeconds(MAX_STREAM_DELAY).count()
+ );
  }
  } // end if streaming stepping or doing nothing
 
  // time_to_event > 0 means that we are not in the event
  if (time_to_event > Seconds(0) and mode == MODE_ALL) {
- TimePoint::duration time_since_last_send = now - last_frame_sent;
  Debug(1, "Time since last send = %.2f s", FPSeconds(time_since_last_send).count());
  if (time_since_last_send > Seconds(1)) {
  char frame_text[64];
@@ -1069,8 +1076,7 @@ void EventStream::runStream() {
  base_fps,
  effective_fps);
  }
- now = std::chrono::steady_clock::now();
- TimePoint::duration elapsed = now - start;
+ TimePoint::duration elapsed = std::chrono::steady_clock::now() - start;
  delta -= std::chrono::duration_cast<Microseconds>(elapsed); // sending frames takes time, so remove it from the sleep time
 
  Debug(2, "New delta: %fs from last frame offset %fs - next_frame_offset %fs - elapsed %fs",