writesubtitles: Write the video subtitles to a file
onlysubtitles: Downloads only the subtitles of the video
allsubtitles: Downloads all the subtitles of the video
+ listsubtitles: Lists all available subtitles for the video
subtitlesformat: Subtitle format [sbv/srt] (default=srt)
subtitleslang: Language of the subtitles to download
test: Download only first bytes to test the downloader.