[youtube] Use localized title & description

[mjsir911]

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Pulled from - ytdl-org/youtube-dl#28538

Get the localized version of title, description (channel name is already translated ^.^)

• Prioritize microformat title & description over basic title & description

Related:

• [youtube] Extract original title from channel and playlist ytdl-org/youtube-dl#27371
• Support translated titles (youtube) ytdl-org/youtube-dl#13811 Related, alternative feedback. Embed original title somewhere?

Fixes:

• Fixes [Site Request] Support translated/localized YouTube titles and descriptions #387
• Fixes [YouTube] Support Getting Original Titles for Videos That Have Translated Titles ytdl-org/youtube-dl#28421
• Fixes youtube language selection for video title/description ytdl-org/youtube-dl#27738
• Fixes Downloading Youtube playlist containing translated title results in inconsistent title. ytdl-org/youtube-dl#27499
• Fixes Please add workaround for forced YouTube translated video titles ytdl-org/youtube-dl#10758
• Fixes Youtube channel not extract original title ytdl-org/youtube-dl#27075 (why is this closed?)
• Fixes Youtube translated title's dont stick mpv-player/mpv#8676

[pukkandan]

See discussion on #387 and related issues

[mjsir911]

See discussion on #387 and related issues

Yuup and I don't really have the bandwidth to deal with a PR more complicated, just putting this here for posterity.

This PR is desired by users & doesn't break any existing tests, and the fact of the matter is similar localization is already being done for the channel key (and maybe others, I haven't checked).

see this comment for the workaround/explanation as to how to change the languages of the returned metadata using this PR

Additionally, the inconsistencies outlined in mpv-player/mpv#8676 still exist where the playlist's returned title is translated, but the video's metadata on download is untranslated.

All in all, feel free to close this PR in preference of a more refined one maybe coming down the line, but consider adding tests that would cause these changes to fail them in an effort to document your stance.

[coletdjnz]

To add on, unfortunately I don't think PR will really work as intended with yt-dlp atm anyways 😕. Recently we made a change that enforces English regardless of user provided cookies/lang header (see #387 (comment)).

[mjsir911]

To add on, unfortunately I don't think PR will really work as intended with yt-dlp atm anyways. Recently we made a change that enforces English regardless of user provided cookies/lang header

I appreciate the addition, testing this out I can confirm this behaviour:

$ yt-dlp --get-title UnIhRpIT7nc --add-header 'Accept-Language: en'
inabakumori - Lagtrain (Vo. Kaai Yuki) / 稲葉曇『ラグトレイン』Vo. 歌愛ユキ
$ yt-dlp --get-title UnIhRpIT7nc --add-header 'Accept-Language: es'
inabakumori - Lagtrain (Vo. Kaai Yuki) / 稲葉曇『ラグトレイン』Vo. 歌愛ユキ

Additionally with the (existing) channel metadata:

$ yt-dlp -j UnIhRpIT7nc --add-header 'Accept-Language: en' | jq -S .channel
"inabakumori"
$ yt-dlp -j UnIhRpIT7nc --add-header 'Accept-Language: es' | jq -S .channel
"inabakumori"