diff --git a/plugins/thumbnails/thumbnails.php b/plugins/thumbnails/thumbnails.php
index 6a89c0d..968f6fe 100644
--- a/plugins/thumbnails/thumbnails.php
+++ b/plugins/thumbnails/thumbnails.php
@@ -161,7 +161,7 @@ class thumbnailGenerator extends BaseProcessor
         $mimeType = KTMime::getMimeTypeName($mimeTypeId);
 
 	    // Get the pdf source file - if the document is a pdf then use the document as the source
-	    if($mimeType == 'application/pdf') {
+	    if($mimeType == 'application/pdf' || $mimeType == 'image/png' || $mimeType == 'image/jpeg' ) {
 	        $pdfDir = $default->documentRoot;
             $pdfFile = $pdfDir . DIRECTORY_SEPARATOR . $this->document->getStoragePath();
 	    } else {