Implementing thumbnails formats selection

[andrea-aus-hh]

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Responding to this feature req:
#28726

Trying to add a --thumbnail-format option, that allows the user to choose which of the available thumbnails to download.
It takes the ID (as reported with the --list-thumbnails options) as input, and falls back to the default one (last element of the thumbnails dictionary) if the ID is invalid.
Not sure if it's the best idea to use a separate option like I did, or if it would be better to collapse everything into --write-thumbnail, though I'd be afraid to break existing scripts. Glad to get input on this - well, or any input in general :-)
Pardon the multiple commits.

Usage example:
python -m youtube_dl --write-thumbnail --thumbnail-format 2 https://www.youtube.com/watch?v=YQ04r4HGS-U

[aviv926]

Hi Hello below for the thread I opened #28457 and this thread #28726

I saw that you added the option to the--list-thumbnails
I really appreciate it!

I wanted to ask is it possible to create a command that downloads all the images as a jpg from a YouTube channel?
I tried running the following command but without success:
youtube-dl.exe --write-thumbnail '[ext = jpg]' [URL HERE]
or this
youtube-dl.exe --write-thumbnail -4 --skip-download --output "%(title)s.%(ext)s" [URL HERE]

[Rashad-j]

I this going to be merged by any chance?

[aviv926]

I this going to be merged by any chance?

Check out the enhanced version of youtube-dl
There is a better version called yt dlp and the option is already supported

yt-dlp.exe --skip-download --write-thumbnail --convert-thumbnails jpg **URL HERE**