Request: --only-unwatched

[maciekish]

Make sure you are using the latest version: run youtube-dl --version and ensure your version is 2017.11.26. If it's not, read this FAQ entry and update. Issues with outdated version will be rejected.

• I've verified and I assure that I'm running youtube-dl 2017.11.26

Before submitting an issue make sure you have:

• At least skimmed through the README, most notably the FAQ and BUGS sections
• Searched the bugtracker for similar issues including closed ones

What is the purpose of your issue?

• Bug report (encountered problems with youtube-dl)
• Site support request (request for adding support for a new site)
• Feature request (request for a new functionality)
• Question
• Other

Description of your issue, suggested solution and other information

You already have --mark-watched so it would make sense adding --only-unwatched. This way it would be possible to keep a "Download"-playlist which automatically downloads each video once and doesn't redownload it once deleted locally.

[s104346]

This feature kind of already exists as --download-archive:
https://github.com/rg3/youtube-dl#how-do-i-download-only-new-videos-from-a-playlist

[dstftw]

--download-archive.

[Joshfindit]

I'd like to reopen this, especially for playlists.

Two reasons:

1. A video may be added to the Watch Later playlist then watched before youtube-dl is run. Desired outcome: don't download.
2. A series playlist may have hundreds of videos in a series that have been watched at different times with only a small fraction of them being newly posted (and unwatched). If youtube-dl has never been run on this playlist, the only option is to download all videos.

[Cogito]

A series playlist may have hundreds of videos in a series that have been watched at different times with only a small fraction of them being newly posted (and unwatched). If youtube-dl has never been run on this playlist, the only option is to download all videos.

This is my use case as well.

More specifically, I want to keep my downloaded and not downloaded watch history as in-sync as possible. If I've already watched some videos in a playlist I might want to exclude them when being downloaded. If I've downloaded them I want to mark them as watched.

Half of that story is possible now, I was hoping that the other half might be possible using --match-filter but haven't found out if so yet. The proposed option would provide the required functionality.