From a5b77a59d3827d29263e10b0f1b1b65da7633566 Mon Sep 17 00:00:00 2001
From: Isaac Connor <isaac@zoneminder.com>
Date: Thu, 29 Mar 2018 12:35:03 -0400
Subject: [PATCH] allow 0 pre_event_count

---
 src/zm_monitor.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/zm_monitor.cpp b/src/zm_monitor.cpp
index ed77a90f8..a492fa90a 100644
--- a/src/zm_monitor.cpp
+++ b/src/zm_monitor.cpp
@@ -1485,7 +1485,7 @@ bool Monitor::Analyse() {
               if ( analysis_fps ) {
                 // If analysis fps is set,
                 // compute the index for pre event images in the dedicated buffer
-                pre_index = image_count%pre_event_buffer_count;
+                pre_index = pre_event_buffer_count ? image_count%pre_event_buffer_count : 0;
 
                 // Seek forward the next filled slot in to the buffer (oldest data)
                 // from the current position
@@ -1540,7 +1540,7 @@ bool Monitor::Analyse() {
                 if ( analysis_fps ) {
                   // If analysis fps is set,
                   // compute the index for pre event images in the dedicated buffer
-                  pre_index = image_count%pre_event_buffer_count;
+                  pre_index = pre_event_buffer_count ? image_count%pre_event_buffer_count : 0;
 
                   // Seek forward the next filled slot in to the buffer (oldest data)
                   // from the current position