1 files changed, 7 insertions, 5 deletions
diff --git a/yt_dlp/compat/imghdr.py b/yt_dlp/compat/imghdr.py
index 734b0d876..5d64ab07b 100644
--- a/yt_dlp/compat/imghdr.py
+++ b/yt_dlp/compat/imghdr.py
@@ -2,13 +2,15 @@ tests = {
     'webp': lambda h: h[0:4] == b'RIFF' and h[8:] == b'WEBP',
     'png': lambda h: h[:8] == b'\211PNG\r\n\032\n',
     'jpeg': lambda h: h[6:10] in (b'JFIF', b'Exif'),
+    'gif': lambda h: h[:6] in (b'GIF87a', b'GIF89a'),
 }
 
 
-def what(path):
-    """Detect format of image (Currently supports jpeg, png, webp only)
+def what(file=None, h=None):
+    """Detect format of image (Currently supports jpeg, png, webp, gif only)
     Ref: https://github.com/python/cpython/blob/3.10/Lib/imghdr.py
     """
-    with open(path, 'rb') as f:
-        head = f.read(12)
-    return next((type_ for type_, test in tests.items() if test(head)), None)
+    if h is None:
+        with open(file, 'rb') as f:
+            h = f.read(12)
+    return next((type_ for type_, test in tests.items() if test(h)), None)