[Bug] Thumbnail embed/write behavior

[undaunt]

Checklist

• I'm reporting a broken site support issue
• I've verified that I'm running yt-dlp version 2021.02.04
• I've checked that all provided URLs are alive and playable in a browser
• I've checked that all URLs and arguments with special characters are properly quoted or escaped
• I've searched the bugtracker for similar bug reports including closed ones
• I've read bugs section in FAQ

Description

There is an existing issue for this on yt-dl that isn't getting much traction, wasn't sure if it was more appropriate to mention you there or post it here - sorry if this is incorrect.

ytdl-org/youtube-dl#27041

It is definitely a bug.

• with --write-thumbnail only: the original .webp file is written
• with --embed-thumbnail only: the original .webp file is converted to lossy jpeg, embedded into the media file, then deleted.
• with both options at the same time: the original .webp file is lost, and only the converted .jpg file remains there.

Using the --embed-thumbnail changes the meaning of the --write-thumbnail and causes data loss.

There is an other bug, the --embed-thumbnail does not keep the media file's mtime and changes it to the current timestamp. This is inconsistent because the other embed options keep the mtime.

[pukkandan]

wasn't sure if it was more appropriate to mention you there or post it here - sorry if this is incorrect.

Never mention yt-dlp in the original repo. They will just remove the comment and if you repeat, you'll get banned

There is an other bug, the --embed-thumbnail does not keep the media file's mtime and changes it to the current timestamp. This is inconsistent because the other embed options keep the mtime.

No idea how to fix this

I'll fix the rest

[undaunt]

Thanks very much!

[pukkandan]

Give me an example video to test. The video given in the other issue is private

[undaunt]

This playlist of 5 videos are each less than 10 minutes, all of them downloaded webp for me with write on, but with both on left me with jpg.

https://www.youtube.com/playlist?list=PLz3Be--ot61Mvmms68yBEhX6KrzPrqxsW

[pukkandan]

There is an other bug, the --embed-thumbnail does not keep the media file's mtime and changes it to the current timestamp. This is inconsistent because the other embed options keep the mtime.

Fixed