Add pre-processor stage video

Related: #456, #5808

yt_dlp/YoutubeDL.py

@@ -2977,6 +2977,16 @@ class YoutubeDL:
 
         # Does nothing under normal operation - for backward compatibility of process_info
         self.post_extract(info_dict)
+
+        def replace_info_dict(new_info):
+            nonlocal info_dict
+            if new_info == info_dict:
+                return
+            info_dict.clear()
+            info_dict.update(new_info)
+
+        new_info, _ = self.pre_process(info_dict, 'video')
+        replace_info_dict(new_info)
         self._num_downloads += 1
 
         # info_dict['_filename'] needs to be set for backward compatibility
@@ -3090,13 +3100,6 @@ class YoutubeDL:
                for link_type, should_write in write_links.items()):
             return
 
-        def replace_info_dict(new_info):
-            nonlocal info_dict
-            if new_info == info_dict:
-                return
-            info_dict.clear()
-            info_dict.update(new_info)
-
         new_info, files_to_move = self.pre_process(info_dict, 'before_dl', files_to_move)
         replace_info_dict(new_info)