From 5df2fbfff2826fdde209ba0e6c85c6a9d0870bb8 Mon Sep 17 00:00:00 2001
From: Isaac Connor <isaac@zoneminder.com>
Date: Tue, 15 May 2018 15:53:25 -0400
Subject: [PATCH] fix logic to handle no pre_event frames

---
 src/zm_monitor.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/zm_monitor.cpp b/src/zm_monitor.cpp
index d9b07e40f..e8e14b3c4 100644
--- a/src/zm_monitor.cpp
+++ b/src/zm_monitor.cpp
@@ -1543,7 +1543,7 @@ bool Monitor::Analyse() {
         }
         if ( score ) {
           if ( (state == IDLE || state == TAPE || state == PREALARM ) ) {
-            if ( Event::PreAlarmCount() > alarm_frame_count ) {
+            if ( (!pre_event_count) || (Event::PreAlarmCount() >= alarm_frame_count) ) {
               Info("%s: %03d - Gone into alarm state %u > %u",
                   name, image_count, Event::PreAlarmCount(), alarm_frame_count);
               shared_data->state = state = ALARM;