Animated GIF emoji support

main.py

@@ -9,7 +9,7 @@ import os # Filesystem
 import mimetypes # Uploading files to homeserver
 import html # HTML formatting
 import requests # XKCD command
-import subprocess # ping command (admin)
+import subprocess # GIF Emojis, ping command (admin)
 import random # roll command
 import datetime # Ratelimiting
 
@@ -87,12 +87,23 @@ def download_file(url, filename):
     else:
         return False
 
+# GIF resizing
+def thumbnails(frames, size):
+    for frame in frames:
+        thumbnail = frame.copy()
+        thumbnail.thumbnail((size, size), Image.ANTIALIAS)
+        yield thumbnail
+
 # Resize an image (squares only)
 def resize_image(filename, size):
-    im = Image.open(filename)
-    im = im.resize((size,size))
-    # Remove .ext from the filename, insert _resized into it, and save it
+    original_filename = filename
     filename = filename[:-4] + "_resized" + filename[-4:]
+    if filename.endswith(".gif"):
+        # PIL does not properly hanle GIF images
+        subprocess.run(["gifsicle", "--resize", f"{str(size)}x{str(size)}", original_filename, "-o", filename], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
+    else:
+        im = Image.open(original_filename)
+        im = im.resize((size,size))
         im.save(filename)
     return filename