some minor improvements to preview lib

diff --git a/lib/preview.php b/lib/preview.php
index 3564fe3df446cacd7ea56a3bfabda3b43757e786..87e2e78d1d8a682af67f8a6d08d4a3aff064b98f 100755 (executable)
--- a/lib/preview.php
+++ b/lib/preview.php
@@ -323,7 +323,7 @@ class Preview {
                }else{
                        $mimetype = $this->fileview->getMimeType($file);
 
-                       $preview;
+                       $preview = null;
 
                        foreach(self::$providers as $supportedmimetype => $provider) {
                                if(!preg_match($supportedmimetype, $mimetype)) {
@@ -350,6 +350,11 @@ class Preview {
 
                                break;
                        }
+
+                       if(is_null($preview) || $preview === false) {
+                               $preview = new \OC_Image();
+                       }
+
                        $this->preview = $preview;
                }
                $this->resizeAndCrop();