diff --git a/src/openalpr/alpr.cpp b/src/openalpr/alpr.cpp
index a2e4d66..c42b101 100644
--- a/src/openalpr/alpr.cpp
+++ b/src/openalpr/alpr.cpp
@@ -95,6 +95,10 @@ namespace alpr
     impl->setPrewarp(prewarp_config);
   }
 
+  void Alpr::setMask(unsigned char* pixelData, int bytesPerPixel, int imgWidth, int imgHeight)
+  {
+    impl->setMask(pixelData, bytesPerPixel, imgWidth, imgHeight);
+  }
 
   void Alpr::setDetectRegion(bool detectRegion)
   {
diff --git a/src/openalpr/alpr.h b/src/openalpr/alpr.h
index c34f369..ac6fd43 100644
--- a/src/openalpr/alpr.h
+++ b/src/openalpr/alpr.h
@@ -142,6 +142,8 @@ namespace alpr
       
       // Update the prewarp setting without reloading the library
       void setPrewarp(std::string prewarp_config);
+      // Update the detection mask without reloading the library
+      void setMask(unsigned char* pixelData, int bytesPerPixel, int imgWidth, int imgHeight);
       
       void setDetectRegion(bool detectRegion);
       void setTopN(int topN);
diff --git a/src/openalpr/alpr_impl.cpp b/src/openalpr/alpr_impl.cpp
index 22286de..e930b6c 100644
--- a/src/openalpr/alpr_impl.cpp
+++ b/src/openalpr/alpr_impl.cpp
@@ -680,6 +680,25 @@ namespace alpr
     else
       prewarp->initialize(prewarp_config);
   }
+  
+  void AlprImpl::setMask(unsigned char* pixelData, int bytesPerPixel, int imgWidth, int imgHeight) {
+
+    try
+    {
+      int arraySize = imgWidth * imgHeight * bytesPerPixel;
+      cv::Mat imgData = cv::Mat(arraySize, 1, CV_8U, pixelData);
+      cv::Mat mask = imgData.reshape(bytesPerPixel, imgHeight);
+
+      typedef std::map<std::string, AlprRecognizers>::iterator it_type;
+      for (it_type iterator = recognizers.begin(); iterator != recognizers.end(); iterator++)
+        iterator->second.plateDetector->setMask(mask);
+    }
+    catch (cv::Exception& e)
+    {
+      std::cerr << "Caught (and ignoring) error in setMask: " << e.msg << std::endl;
+    }
+  }
+
 
 
   void AlprImpl::setDetectRegion(bool detectRegion)
diff --git a/src/openalpr/alpr_impl.h b/src/openalpr/alpr_impl.h
index 2aa0da0..0cfd85a 100644
--- a/src/openalpr/alpr_impl.h
+++ b/src/openalpr/alpr_impl.h
@@ -92,6 +92,7 @@ namespace alpr
 
       void setCountry(std::string country);
       void setPrewarp(std::string prewarp_config);
+      void setMask(unsigned char* pixelData, int bytesPerPixel, int imgWidth, int imgHeight);
       
       void setDetectRegion(bool detectRegion);
       void setTopN(int topn);