How to only download subtitles in a specific format？

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• I’m asking a question and not reporting a bug/feature request
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Question

I only want subtitles in a specific format in all languages, if there is no specific format then don’t download any subtitles.

yt-dlp -s -vU --sub-format "ass/srt" --proxy http://127.0.0.1:7890 --all-subs -- https://www.youtube.com/watch?v=YjtC7kw0SRI

But it will download vtt format.

Verbose log

[debug] Command-line config: ['-s', '-vU', '--sub-format', 'ass/srt', '--proxy', 'http://127.0.0.1:7890', '--all-subs', '--', 'https://www.youtube.com/watch?v=YjtC7kw0SRI']
[debug] Encodings: locale cp936, fs utf-8, out utf-8, err utf-8, pref cp936
[debug] yt-dlp version 2022.03.13.43044 [29003cf] (win_exe)
[debug] ** This build is unofficial daily builds, provided for ease of use.
[debug] ** Please do not ask for any support.
[debug] Python version 3.8.10 (CPython 64bit) - Windows-10-10.0.19044-SP0
[debug] exe versions: ffmpeg git-2022-02-22-570fda56 (setts), ffprobe 2022-02-21-git-b8e58f0858-essentials_build-www.gyan.dev
[debug] Optional libraries: brotli, Cryptodome, mutagen, sqlite, websockets
[debug] Proxy map: {'http': 'http://127.0.0.1:7890', 'https': 'http://127.0.0.1:7890'}
Latest version: 2022.03.13.43044, Current version: 2022.03.13.43044
yt-dlp is up to date (2022.03.13.43044)
[debug] [youtube] Extracting URL: https://www.youtube.com/watch?v=YjtC7kw0SRI
[youtube] YjtC7kw0SRI: Downloading webpage
[youtube] YjtC7kw0SRI: Downloading android player API JSON
[debug] Sort order given by extractor: quality, res, fps, hdr:12, source, codec:vp9.2, lang, proto
[debug] Formats sorted by: hasvid, ie_pref, quality, res, fps, hdr:12(7), source, vcodec:vp9.2(10), acodec, lang, proto, filesize, fs_approx, tbr, vbr, abr, asr, vext, aext, hasaud, id
[debug] Downloading subtitles: zh-Hans, zh-Hant, en, id
WARNING: No subtitle format found matching "ass/srt" for language zh-Hans, using vtt
WARNING: No subtitle format found matching "ass/srt" for language zh-Hant, using vtt
WARNING: No subtitle format found matching "ass/srt" for language en, using vtt
WARNING: No subtitle format found matching "ass/srt" for language id, using vtt
[debug] Default format spec: bestvideo*+bestaudio/best
[info] YjtC7kw0SRI: Downloading 1 format(s): 248+251

[Yay295]

VTT and srt are basically just timed text (although VTT theoretically can hold much more - YT does not make use of those features and just includes text and timing)

Here’s a video with colored subtitles and karaoke: https://www.youtube.com/watch?v=_VIeV_LZXHM

[SalimF]

RROR: [generic] '—-convert-subs' is not a valid URL. Set --default-search "ytsearch" (or run yt-dlp "ytsearch:—-convert-subs" ) to search YouTube

Ok it’s works --convert-subs "ass"