diff --git a/phototrie/phototrie.py b/phototrie/phototrie.py
index 7699b87..b5c93a5 100644
--- a/phototrie/phototrie.py
+++ b/phototrie/phototrie.py
@@ -17,9 +17,9 @@ def prepare_processable(search_in: str):
     for file in sorted(os.listdir(search_in)):
         if file.endswith(extension):
             full_path = search_in + "/" + file
-            thumb_path = tmp_dir + "/" + file + ".jpg"
+            thumb_path = tmp_dir + "/" + file + ".webp"
             image = Image.open(file)
-            image.thumbnail((512, 512))
+            image.thumbnail((768, 768))
             image.save(thumb_path)
 
             # also search for raw CR2