diff --git a/src/zm_detector.cpp b/src/zm_detector.cpp
index c8d8dd5bf..fca106ec1 100644
--- a/src/zm_detector.cpp
+++ b/src/zm_detector.cpp
@@ -94,7 +94,7 @@ void Detector::log(int nLogLevel, string sLevel, string sMessage)
  *  \param score is the detection score
  *  \return true if detection is effective
  */
-bool Detector::Detect(const Image* zmImage, Zone** zones, Event::StringSet &zoneSet, unsigned int &score)
+bool Detector::Detect(const Image &zmImage, Zone** zones, Event::StringSet &zoneSet, unsigned int &score)
 {
     bool alarm = false;
     char szMessage[100];
@@ -112,7 +112,7 @@ bool Detector::Detect(const Image* zmImage, Zone** zones, Event::StringSet &zone
             continue;
         sprintf(szMessage, "Checking preclusive zone %s", zone->Label());
         log(LOG_DEBUG, "DEBUG", szMessage);
-        if (checkZone(zone, *it, *zmImage))
+        if (checkZone(zone, *it, &zmImage))
         {
             alarm = true;
             score += zone->Score();
@@ -145,7 +145,7 @@ bool Detector::Detect(const Image* zmImage, Zone** zones, Event::StringSet &zone
                 continue;
             if (zone->IsPostProcEnabled() && !zone->IsPostProcInProgress())
                 continue;
-            if (checkZone(zone, *it, *zmImage))
+            if (checkZone(zone, *it, &zmImage))
             {
                 alarm = true;
                 score += zone->Score();
@@ -176,7 +176,7 @@ bool Detector::Detect(const Image* zmImage, Zone** zones, Event::StringSet &zone
                     continue;
                 sprintf(szMessage, "Checking inclusive zone %s", zone->Label());
                 log(LOG_DEBUG, "DEBUG", szMessage);
-                if (checkZone(zone, *it, *zmImage))
+                if (checkZone(zone, *it, &zmImage))
                 {
                     alarm = true;
                     score += zone->Score();
@@ -207,7 +207,7 @@ bool Detector::Detect(const Image* zmImage, Zone** zones, Event::StringSet &zone
                     continue;
                 sprintf(szMessage, "Checking exclusive zone %s", zone->Label());
                 log(LOG_DEBUG, "DEBUG", szMessage);
-                if (checkZone(zone, *it, *zmImage))
+                if (checkZone(zone, *it, &zmImage))
                 {
                     alarm = true;
                     score += zone->Score();
diff --git a/src/zm_detector.h b/src/zm_detector.h
index b82e6f1b0..9850bda6d 100644
--- a/src/zm_detector.h
+++ b/src/zm_detector.h
@@ -76,7 +76,7 @@ public:
     Detector& operator=(const Detector& source);
 
     //! Detect (in an image later)
-    bool Detect(const Image* image, Zone** zones, Event::StringSet &zoneSet, unsigned int &score);
+    bool Detect(const Image &image, Zone** zones, Event::StringSet &zoneSet, unsigned int &score);
 
     //! Load detector's parameters.
     virtual int loadConfig(string sConfigFileName, map<unsigned int,map<string,string> > mapPluginConf) = 0;
diff --git a/src/zm_image_analyser.cpp b/src/zm_image_analyser.cpp
index 9d51b514e..20e02fda6 100644
--- a/src/zm_image_analyser.cpp
+++ b/src/zm_image_analyser.cpp
@@ -61,7 +61,7 @@ bool ImageAnalyser::DoDetection(const Image &comp_image, Zone** zones, Event::St
         ++It )
     {
         unsigned int detect_score = 0;
-        if ( (*It)->Detect( &comp_image, zones, zoneSet, detect_score ) )
+        if ( (*It)->Detect( comp_image, zones, zoneSet, detect_score ) )
         {
             alarm = true;
             score += detect_score;