[ie/youtube] Add `player_params` extractor arg (#7719)

Authored by: coletdjnz

README.md

@@ -1802,6 +1802,7 @@ The following extractors use this feature:
 * `skip`: One or more of `hls`, `dash` or `translated_subs` to skip extraction of the m3u8 manifests, dash manifests and [auto-translated subtitles](https://github.com/yt-dlp/yt-dlp/issues/4090#issuecomment-1158102032) respectively
 * `player_client`: Clients to extract video data from. The main clients are `web`, `android` and `ios` with variants `_music`, `_embedded`, `_embedscreen`, `_creator` (e.g. `web_embedded`); and `mweb` and `tv_embedded` (agegate bypass) with no variants. By default, `ios,android,web` is used, but `tv_embedded` and `creator` variants are added as required for age-gated videos. Similarly, the music variants are added for `music.youtube.com` urls. You can use `all` to use all the clients, and `default` for the default clients.
 * `player_skip`: Skip some network requests that are generally needed for robust extraction. One or more of `configs` (skip client configs), `webpage` (skip initial webpage), `js` (skip js player). While these options can help reduce the number of requests needed or avoid some rate-limiting, they could cause some issues. See [#860](https://github.com/yt-dlp/yt-dlp/pull/860) for more details
+* `player_params`: YouTube player parameters to use for player requests. Will overwrite any default ones set by yt-dlp.
 * `comment_sort`: `top` or `new` (default) - choose comment sorting mode (on YouTube's side)
 * `max_comments`: Limit the amount of comments to gather. Comma-separated list of integers representing `max-comments,max-parents,max-replies,max-replies-per-thread`. Default is `all,all,all,all`
     * E.g. `all,all,1000,10` will get a maximum of 1000 replies total, with up to 10 replies per thread. `1000,all,100` will get a maximum of 1000 comments, with a maximum of 100 replies total

yt_dlp/extractor/youtube.py

@@ -3583,8 +3583,6 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
     def _is_unplayable(player_response):
         return traverse_obj(player_response, ('playabilityStatus', 'status')) == 'UNPLAYABLE'
 
-    _PLAYER_PARAMS = 'CgIQBg=='
-
     def _extract_player_response(self, client, video_id, master_ytcfg, player_ytcfg, player_url, initial_pr, smuggled_data):
 
         session_index = self._extract_session_index(player_ytcfg, master_ytcfg)
@@ -3597,7 +3595,11 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
             'videoId': video_id,
         }
         if _split_innertube_client(client)[0] == 'android':
-            yt_query['params'] = self._PLAYER_PARAMS
+            yt_query['params'] = 'CgIQBg=='
+
+        pp_arg = self._configuration_arg('player_params', [None])[0]
+        if pp_arg:
+            yt_query['params'] = pp_arg
 
         yt_query.update(self._generate_player_context(sts))
         return self._extract_response(
@@ -4016,6 +4018,9 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
         webpage = None
         if 'webpage' not in self._configuration_arg('player_skip'):
             query = {'bpctr': '9999999999', 'has_verified': '1'}
+            pp = self._configuration_arg('player_params', [None])[0]
+            if pp:
+                query['pp'] = pp
             webpage = self._download_webpage(
                 webpage_url, video_id, fatal=False, query=query)