** Description Extracts video subtitles using [[https://github.com/yt-dlp][yt-dlp]] (recommended) or ~youtube-dl~ (poorly supported) and shows them in a buffer.
I was having a conversation one day and I couldn't recall the name of a term, something I learned from a YouTube video. That bothered me. After the chat, I went back to YouTube, found the video, and started searching through it. I increased the playback speed and went back and forth but still couldn't find it. After a few minutes of that struggle, I thought: "what the heck am I doing?". Then I wrote a tiny elisp function to extract subtitles. While reading through the subs I realized how much good stuff went past my ears (while watching the video), so I made it into a package.
** Prerequisites It works by calling ~yt-dlp~ (preferred), or ~youtube-dl~ command line utility. Make sure at least one of them is installed and available at ~$PATH~.
*** Why ~yt-dlp~ is a preferred option? ~yt-dlp~ is a ~youtube-dl~ fork that adds new features and fixes known bugs. Notably, it knows how to extract auto-generated subtitles, and ~youtube-dl~ does not (there's an outstanding bug that needs [[https://github.com/ytdl-org/youtube-dl/issues/29623][fixing]] - /as of October 2022/).
Without the option of extracting auto-generated subtitles, this package would be useless for the majority of videos on YouTube.
Update: Initially, it was written with the support of ~youtube-dl~, but lately, I've been using it exclusively with ~yt-dlp~. There are minor differences between these two tools, and the proper work with ~youtube-dl~ at this point is not guaranteed.
** Installation & Customization *** Install [[https://github.com/yt-dlp/yt-dlp#installation][yt-dlp]], /unless already installed/
*** Package is available on MELPA You can install it using your favorite Emacs package management tool.
*** Doom config example: packages.el
(package! youtube-sub-extractor)
config.el
(use-package! youtube-sub-extractor :commands (youtube-sub-extractor-extract-subs) :config (map! :map youtube-sub-extractor-subtitles-mode-map :desc "copy timestamp URL" :n "RET" #'youtube-sub-extractor-copy-ts-link :desc "browse at timestamp" :n "C-c C-o" #'youtube-sub-extractor-browse-ts-link))
(setq youtube-sub-extractor-timestamps 'left-margin)
*** Customization The package is simple and the main command is ~youtube-sub-extractor-extract-subs~ You can bind it to a key if you like:
(global-set-key "C-c C-x y" #'youtube-sub-extractor-extract-subs)
Doom users probably would want to use the leader key, e.g.,
(map! :leader :desc "YouTube subs" "oy" #''youtube-sub-extractor-extract-subs)
Other customizable vars are:
~youtube-sub-extractor-timestamps~ (default ~right-margin~) - sets the way how timestamps should be displayed, either as overlays on the ~right-margin~ or ~left-margin~, or they need to be printed, for example, if you want to copy the text and include the timestamps, in that case, set the value to ~left-side-text~.
~youtube-sub-extractor-executable-path~ (default ~nil~). The package tries to find the required executable at =$PATH=, but you may have to set the full path to it explicitly.
~youtube-sub-extractor-min-chunk-size~ (default ~5~ seconds). YouTube very often chunks up the subs into pieces too small (a couple of seconds), especially for auto-generated subs. You may want to set different size.
~youtube-sub-extractor-language-choice~ (default ~t~). Just leave it as is and it will always ask for when multiple language choices are available. If you're only interested in a specific language, set the var. See the docstring for details.
In the subtitles buffer (when subs get successfully extracted) it enables a minor mode, so you can bind keys to specific commands. By default, they are set to ~RET~ (to copy the link to the video at a specific timestamp) and ~C-c C-o~ (to browse the video at the timestamp), you can change those, e.g.,
(define-key youtube-sub-extractor-subtitles-mode-map (kbd "C-RET")
(define-key youtube-sub-extractor-subtitles-mode-map (kbd "C-c b")
Evil (non-Doom) users can do it like so, Doom users see previous section:
(evil-define-minor-mode-key 'normal 'youtube-sub-extractor-subtitles-mode (kbd "C-RET") #'youtube-sub-extractor-copy-ts-link)