Added error message when input image/video file is not found

src/main.cpp

@@ -20,6 +20,7 @@
 
 
  #include <iostream>
+#include <valarray>
  #include <stdio.h>
  #include <sys/stat.h>
 
@@ -138,6 +139,8 @@
     }
   }
   else if (hasEnding(filename, ".avi") || hasEnding(filename, ".mp4") || hasEnding(filename, ".webm") || hasEnding(filename, ".flv"))
+  {
+    if (fileExists(filename.c_str()))
     {
       int framenum = 0;
       
@@ -158,13 +161,25 @@
 	  cv::waitKey(1);
 	  framenum++;
       }
+    }
+    else
+    {
+      std::cerr << "Video file not found: " << filename << std::endl;
+    }
      
   }
   else if (hasEnding(filename, ".png") || hasEnding(filename, ".jpg") || hasEnding(filename, ".gif"))
+  {
+    if (fileExists(filename.c_str()))
     {
       frame = cv::imread( filename );
     
       detectandshow( &alpr, frame, "", outputJson);
+    }
+    else
+    {
+      std::cerr << "Image file not found: " << filename << std::endl;
+    }
       
       
   }