From c389561754db39880aca3a8646af24f27c8a52e8 Mon Sep 17 00:00:00 2001
From: Matt Hill <matthill@gmail.com>
Date: Mon, 2 Jun 2014 20:52:28 -0400
Subject: [PATCH] Check for invalid images before attempting to detect

---
 src/openalpr/alpr_impl.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/openalpr/alpr_impl.cpp b/src/openalpr/alpr_impl.cpp
index 156734d..c9a4ad0 100644
--- a/src/openalpr/alpr_impl.cpp
+++ b/src/openalpr/alpr_impl.cpp
@@ -70,6 +70,15 @@ std::vector<AlprResult> AlprImpl::recognize(cv::Mat img)
   getTime(&startTime);
   
 
+  if (!img.data)
+  {
+    // Invalid image
+    if (this->config->debugGeneral)
+      std::cerr << "Invalid image" << std::endl;
+    
+    vector<AlprResult> emptyVector;
+    return emptyVector;
+  }
 
   // Find all the candidate regions
   vector<PlateRegion> plateRegions = plateDetector->detect(img);