diff --git a/udev-device-plug-handler/udev-device-plug-handler b/udev-device-plug-handler/udev-device-plug-handler
index 76eaf2e..2b9f00f 100644
--- a/udev-device-plug-handler/udev-device-plug-handler
+++ b/udev-device-plug-handler/udev-device-plug-handler
@@ -134,9 +134,10 @@ class CanonLIDE400(KnownDevice):
             '-y', '297mm',
             '--mode=Color',
             '--resolution', '300dpi',
+            '--format', 'png',
             '--button-controlled=yes',
             # '-p',  # progress
-            f"--batch=scan_{now.strftime('%H%M%S')}_%04d.pnm"
+            f"--batch=scan_{now.strftime('%H%M%S')}_%04d.png"
         ]
         CanonLIDE400.__process = subprocess.Popen(cmd, stdout=subprocess.DEVNULL, cwd=directory)
         print("Handled Canon LiDE 400")