diff --git a/src/Drivers/Gd/Color.php b/src/Drivers/Gd/Color.php
index 351072bd..a7ef9a53 100644
--- a/src/Drivers/Gd/Color.php
+++ b/src/Drivers/Gd/Color.php
@@ -54,4 +54,9 @@ class Color extends AbstractColor implements ColorInterface
 
         return [$r, $g, $b, $a];
     }
+
+    public function toInt(): int
+    {
+        return $this->value;
+    }
 }
diff --git a/src/Drivers/Gd/Modifiers/FillModifier.php b/src/Drivers/Gd/Modifiers/FillModifier.php
index c2eb41d8..8306e762 100644
--- a/src/Drivers/Gd/Modifiers/FillModifier.php
+++ b/src/Drivers/Gd/Modifiers/FillModifier.php
@@ -24,7 +24,7 @@ class FillModifier implements ModifierInterface
         $filling = $this->getApplicableFilling();
 
         foreach ($image as $frame) {
-            imagefilledrectangle($frame->getCore(), 0, 0, $width - 1, $height - 1, $filling);
+            imagefilledrectangle($frame->getCore(), 0, 0, $width - 1, $height - 1, $filling->toInt());
         }
 
         return $image;