fixing qrcode merge error

Author: lyekumchew

src/Image.php

@@ -50,4 +50,14 @@ public function getImageResource()
     {
         return $this->image;
     }
+
+    /**
+     * Sets the image string.
+     *
+     * @param resource $image
+     */
+    public function setImageResource($image)
+    {
+        $this->image = $image;
+    }
 }

src/ImageMerge.php

@@ -107,8 +107,24 @@ public function merge($percentage)
     {
         $this->setProperties($percentage);
 
-        imagecopyresampled(
+        $img = imagecreatetruecolor($this->sourceImage->getWidth(), $this->sourceImage->getHeight());
+        imagealphablending($img, true);
+        $transparent = imagecolorallocatealpha($img, 0, 0, 0, 127);
+        imagefill($img, 0, 0, $transparent);
+
+        imagecopy(
+            $img,
             $this->sourceImage->getImageResource(),
+            0,
+            0,
+            0,
+            0,
+            $this->sourceImage->getWidth(),
+            $this->sourceImage->getHeight()
+        );
+
+        imagecopyresampled(
+            $img,
             $this->mergeImage->getImageResource(),
             $this->centerX,
             $this->centerY,
@@ -120,6 +136,8 @@ public function merge($percentage)
             $this->mergeImageHeight
         );
 
+        $this->sourceImage->setImageResource($img);
+
         return $this->createImage();
     }