Move analysis image assignment up to where motion detection is done do remove duplication and simplify logic. Free analysis images as well as captured images after analysis. remove extra copy of image to analysis_image. Replae a packetqueue.unlock with just deleting the locked packet. No one waits for analysis. Re-introduce sleeping in the analysis thread on error to prevent spinning

src/zm_monitor.cpp

@@ -1849,12 +1849,10 @@ bool Monitor::Analyse() {
 
   // Need to guard around event creation/deletion from Reload()
   std::lock_guard<std::mutex> lck(event_mutex);
-  Debug(3, "Have event lock");
 
   // if we have been told to be OFF, then we are off and don't do any processing.
   if (trigger_data->trigger_state != TriggerState::TRIGGER_OFF) {
     Debug(4, "Trigger not OFF state is (%d)", int(trigger_data->trigger_state));
-    int score = 0;
     // Ready means that we have captured the warmup # of frames
     if (!Ready()) {
       Debug(3, "Not ready?");
@@ -1862,6 +1860,7 @@ bool Monitor::Analyse() {
       return false;
     }
 
+    int score = 0;
     std::string cause;
     Event::StringSetMap noteSetMap;
 
@@ -1886,6 +1885,8 @@ bool Monitor::Analyse() {
       score += trigger_data->trigger_score;
       Debug(1, "Triggered on score += %d => %d", trigger_data->trigger_score, score);
       if (!event) {
+        if (!cause.empty())
+          cause += ", ";
         cause += trigger_data->trigger_cause;
       }
       Event::StringSet noteSet;
@@ -1904,7 +1905,7 @@ bool Monitor::Analyse() {
         }
       } else if (function == MOCORD or function == RECORD) {
         if (!event) {
-          if (cause.length()) cause += ", ";
+          if (!cause.empty()) cause += ", ";
           cause += SIGNAL_CAUSE + std::string(": Reacquired");
         } else {
           event->addNote(SIGNAL_CAUSE, "Reacquired");
@@ -1963,7 +1964,7 @@ bool Monitor::Analyse() {
             packetqueue.unlock(packet_lock); // This will delete packet_lock and notify_all
             packetqueue.wait();
             // Everything may have changed, just return and start again.  This needs to be more RAII
-            return false;
+            return true;
           }  // end while ! decoded
         }  // end if decoding enabled
 
@@ -1981,17 +1982,19 @@ bool Monitor::Analyse() {
           }
 
           if (snap->image) {
-            alarm_image.Assign(*(snap->image));
 
             // decoder may not have been able to provide an image
             if (!ref_image.Buffer()) {
               Debug(1, "Assigning instead of Detecting");
               ref_image.Assign(*(snap->image));
+              alarm_image.Assign(*(snap->image));
             } else if (!(analysis_image_count % (motion_frame_skip+1))) {
               Debug(1, "Detecting motion on image %d, image %p", snap->image_index, snap->image);
               // Get new score.
               int motion_score = DetectMotion(*(snap->image), zoneSet);
 
+              if (!snap->analysis_image)
+                snap->analysis_image = new Image(*(snap->image));
               // lets construct alarm cause. It will contain cause + names of zones alarmed
               snap->zone_stats.reserve(zones.size());
               for (const Zone &zone : zones) {
@@ -2001,8 +2004,11 @@ bool Monitor::Analyse() {
                 if (zone.Alarmed()) {
                   if (!snap->alarm_cause.empty()) snap->alarm_cause += ",";
                   snap->alarm_cause += std::string(zone.Label());
+                  if (zone.AlarmImage())
+                    snap->analysis_image->Overlay(*(zone.AlarmImage()));
                 }
               }
+              alarm_image.Assign(*(snap->analysis_image));
               Debug(3, "After motion detection, score:%d last_motion_score(%d), new motion score(%d)",
                   score, last_motion_score, motion_score);
               motion_frame_count += 1;
@@ -2015,13 +2021,14 @@ bool Monitor::Analyse() {
               } // end if motion_score
             } else {
               Debug(1, "Skipped motion detection last motion score was %d", last_motion_score);
+              alarm_image.Assign(*(snap->image));
             }
           } else {
             Debug(1, "no image so skipping motion detection");
           }  // end if has image
           score += last_motion_score;
         } else {
-          Debug(1, "Not Active(%d) enabled %d active %d doing motion detection: %d",
+          Debug(1, "Not Active(%d) enabled %d shared->active %d doing motion detection: %d",
               Active(), enabled, shared_data->active,
               (function == MODECT or function == MOCORD)
               );
@@ -2167,34 +2174,9 @@ bool Monitor::Analyse() {
         snap->score = score;
 
         if (state == PREALARM) {
-          // Generate analysis images if necessary
-          if (snap->image) {
-            for (const Zone &zone : zones) {
-              if (zone.Alarmed() and zone.AlarmImage()) {
-                  if (!snap->analysis_image)
-                    snap->analysis_image = new Image(*(snap->image));
-                  snap->analysis_image->Overlay(*(zone.AlarmImage()));
-              } // end if zone is alarmed
-            } // end foreach zone
-            if (snap->analysis_image != nullptr)
-            alarm_image.Assign(*(snap->analysis_image));
-          } // end if image.
-
           // incremement pre alarm image count
           Event::AddPreAlarmFrame(snap->image, timestamp, score, nullptr);
         } else if (state == ALARM) {
-          if (snap->image) {
-            for (const Zone &zone : zones) {
-              if (zone.Alarmed() and zone.AlarmImage()) {
-                if (!snap->analysis_image)
-                  snap->analysis_image = new Image(*(snap->image));
-                snap->analysis_image->Overlay(*(zone.AlarmImage()));
-              }  // end if zone is alarmed
-            }  // end foreach zone
-            if (snap->analysis_image != nullptr)
-            alarm_image.Assign(*(snap->analysis_image));
-          }
-
           if (event) {
             if (noteSetMap.size() > 0)
               event->updateNotes(noteSetMap);
@@ -2246,12 +2228,19 @@ bool Monitor::Analyse() {
 
   // In the case where people have pre-alarm frames, the web ui will generate the frame images
   // from the mp4. So no one will notice anyways.
-  if (snap->image and (videowriter == PASSTHROUGH) and !savejpegs) {
+  if (snap->image and (videowriter == PASSTHROUGH)) {
+   if (!savejpegs) {
      Debug(1, "Deleting image data for %d", snap->image_index);
      // Don't need raw images anymore
      delete snap->image;
      snap->image = nullptr;
    }
+   if (snap->analysis_image and !(savejpegs & 2)) {
+     Debug(1, "Deleting analysis image data for %d", snap->image_index);
+     delete snap->analysis_image;
+     snap->analysis_image = nullptr;
+   }
+  }
 
   packetqueue.clearPackets(snap);
 
@@ -2261,7 +2250,8 @@ bool Monitor::Analyse() {
     analysis_image_count++;
   }
   packetqueue.increment_it(analysis_it);
-  packetqueue.unlock(packet_lock);
+  delete packet_lock;
+  //packetqueue.unlock(packet_lock);
   shared_data->last_read_time = std::chrono::system_clock::to_time_t(std::chrono::system_clock::now());
 
   return true;