[rmrector]

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Thank you for your reply.

Exactly, I use TMM.
The illustrations are all in the folder of the film. No need for additional folder, and if it is necessary to rebuild its database one does not use the data on line every time, at least the waiters do not force.

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Thank you. 

Storing these images in a central directory keeps all the images locally for a rebuild or additional Kodi installs just as well, and avoids the noted file synchronization problems. That option is to pull artwork from a parent directory of the movies if that parent is for the movie set. For instance, if your movie folders are stored like "AllMovies/Alien Collection/Alien (1979)/Alien (1979).mkv", this will find movie set artwork stored like "AllMovies/Alien Collection/fanart.jpg". I don't like this strategy for other reasons, though, but it does also avoid the noted problems.

I haven't come across any other tools that work with movie set artwork stored this way, but I do see several that use the Movie Set Artwork Automator style, including TMM. It seems a bad idea to support a third option that introduces a new set of problems and isn't really supported.