diff --git a/backend/db.js b/backend/db.js
index b7298d0..38dfdcb 100644
--- a/backend/db.js
+++ b/backend/db.js
@@ -15,7 +15,7 @@ function initialize(input_db, input_users_db, input_logger) {
     setLogger(input_logger);
 }
 
-function registerFileDB(file_path, type, multiUserMode = null, sub = null, customPath = null) {
+function registerFileDB(file_path, type, multiUserMode = null, sub = null, customPath = null, category = null) {
     let db_path = null;
     const file_id = file_path.substring(0, file_path.length-4);
     const file_object = generateFileObject(file_id, type, customPath || multiUserMode && multiUserMode.file_path, sub);
@@ -29,6 +29,9 @@ function registerFileDB(file_path, type, multiUserMode = null, sub = null, custo
     // add thumbnail path
     file_object['thumbnailPath'] = utils.getDownloadedThumbnail(file_id, type, customPath || multiUserMode && multiUserMode.file_path);
 
+    // if category exists, only include essential info
+    if (category) file_object['category'] = {name: category['name'], uid: category['uid']};
+
     if (!sub) {
         if (multiUserMode) {
             const user_uid = multiUserMode.user;