diff --git a/labelImg.py b/labelImg.py
index a817a653..75f7c87a 100755
--- a/labelImg.py
+++ b/labelImg.py
@@ -1040,7 +1040,7 @@ class MainWindow(QMainWindow, WindowMixin):
             self.loadFile(filename)
 
     def scanAllImages(self, folderPath):
-        extensions = ['.jpeg', '.jpg', '.png', '.bmp']
+        extensions = ['.%s' % fmt.data().decode("ascii").lower() for fmt in QImageReader.supportedImageFormats()]
         images = []
 
         for root, dirs, files in os.walk(folderPath):