fourstring
diff --git a/‎pyrogram/client/client.py‎
Lines changed: 20 additions & 8 deletions b/‎pyrogram/client/client.py‎
Lines changed: 20 additions & 8 deletions
diff --git a/‎pyrogram/client/ext/base_client.py‎
Lines changed: 21 additions & 0 deletions b/‎pyrogram/client/ext/base_client.py‎
Lines changed: 21 additions & 0 deletions
@@ -861,18 +861,20 @@ def download_worker(self):
                 file_name = file_name or getattr(media, "file_name", None)
 
                 if not file_name:
-                    if media_type == 3:
-                        extension = ".ogg"
+                    guessed_extension = self.guess_extension(media.mime_type)
+
+                    if media_type in (0, 1, 2):
+                        extension = ".jpg"
+                    elif media_type == 3:
+                        extension = guessed_extension or ".ogg"
                     elif media_type in (4, 10, 13):
-                        extension = mimetypes.guess_extension(media.mime_type) or ".mp4"
+                        extension = guessed_extension or ".mp4"
                     elif media_type == 5:
-                        extension = mimetypes.guess_extension(media.mime_type) or ".unknown"
+                        extension = guessed_extension or ".zip"
                     elif media_type == 8:
-                        extension = ".webp"
+                        extension = guessed_extension or ".webp"
                     elif media_type == 9:
-                        extension = mimetypes.guess_extension(media.mime_type) or ".mp3"
-                    elif media_type in (0, 1, 2):
-                        extension = ".jpg"
+                        extension = guessed_extension or ".mp3"
                     else:
                         continue
 
@@ -1708,3 +1710,13 @@ def get_file(self,
             return ""
         else:
             return file_name
+
+    def guess_mime_type(self, filename: str):
+        extension = os.path.splitext(filename)[1]
+        return self.extensions_to_mime_types.get(extension)
+
+    def guess_extension(self, mime_type: str):
+        extensions = self.mime_types_to_extensions.get(mime_type)
+
+        if extensions:
+            return extensions.split(" ")[0]
@@ -16,6 +16,7 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with Pyrogram.  If not, see <http://www.gnu.org/licenses/>.
 
+import os
 import platform
 import re
 from queue import Queue
@@ -67,6 +68,20 @@ class StopTransmission(StopIteration):
         13: "video_note"
     }
 
+    mime_types_to_extensions = {}
+    extensions_to_mime_types = {}
+
+    with open("{}/mime.types".format(os.path.dirname(__file__)), "r", encoding="UTF-8") as f:
+        for match in re.finditer(r"^([^#\s]+)\s+(.+)$", f.read(), flags=re.M):
+            mime_type, extensions = match.groups()
+
+            extensions = [".{}".format(ext) for ext in extensions.split(" ")]
+
+            for ext in extensions:
+                extensions_to_mime_types[ext] = mime_type
+
+            mime_types_to_extensions[mime_type] = " ".join(extensions)
+
     def __init__(self):
         self.is_bot = None
         self.dc_id = None
@@ -132,3 +147,9 @@ def get_chat_members_count(self, *args, **kwargs):
 
     def answer_inline_query(self, *args, **kwargs):
         pass
+
+    def guess_mime_type(self, *args, **kwargs):
+        pass
+
+    def guess_extension(self, *args, **kwargs):
+        pass