diff --git a/WebApp/Coordinate.cs b/WebApp/Coordinate.cs
index 0b94bee..9985937 100644
--- a/WebApp/Coordinate.cs
+++ b/WebApp/Coordinate.cs
@@ -6,7 +6,15 @@ internal record Coordinate
     public string Name { get; }
     public int Row { get; }
     public int Col { get; }
-    public string Path => BasePath + Name + ".png";
+
+    public string FullPath
+    {
+        get
+        {
+            string filename = Name + ".png";
+            return Path.Combine(BasePath, filename);
+        }
+    }
 
     public Coordinate(string name)
     {
diff --git a/WebApp/ImageGenerator.cs b/WebApp/ImageGenerator.cs
index a482e59..711beb8 100644
--- a/WebApp/ImageGenerator.cs
+++ b/WebApp/ImageGenerator.cs
@@ -9,7 +9,7 @@ public class ImageGenerator
         string[] inputs = requestBody.CanvasRect.Split(":");
         double scale = requestBody.OutputScale;
         Coordinate a1 = new Coordinate("A1");
-        Mat a1Mat = new Mat(a1.Path);
+        Mat a1Mat = new Mat(a1.FullPath);
         int width = a1Mat.Width;
         int height = a1Mat.Height;
         if (scale < 1)
@@ -36,7 +36,7 @@ public class ImageGenerator
         {
             try
             {
-                Mat mat = new Mat(item.Path);
+                Mat mat = new Mat(item.FullPath);
                 if (scale < 1)
                 {
                     mat = mat.Resize(new Size(width, height));