diff --git a/ext/image/main.php b/ext/image/main.php
index a73be90c..8709ddf7 100644
--- a/ext/image/main.php
+++ b/ext/image/main.php
@@ -183,7 +183,9 @@ class ImageIO extends Extension
             $tags_to_set = $image->get_tag_array();
             $image->tag_array = [];
             send_event(new TagSetEvent($image, $tags_to_set));
-            send_event(new SourceSetEvent($image, $image->source));
+            if ($image->source) {
+                send_event(new SourceSetEvent($image, $image->source));
+            }
         } catch (ImageAdditionException $e) {
             throw new UploadException($e->error);
         }