Embed metadata: preserve aspect ratio on covers

[Lukusaukko]

I've been using Calibre for ages, but until I just recently got my first real e-reader and started seeing the stretched covers, I haven't noticed this: if I use Embed Metadata from the library view, it sets a cover without preserving the aspect ratio, and I have to reset the cover in editor so I can enable it.

Is it possible to configure this somewhere? The plugin configuration only allows the option to disable embedding the cover for books that don't already have one, as far as I can tell.

[kovidgoyal]

embedding metadata does not touch the HTML used to display covers. It only sets the actual cover image, so there is no aspect ratio to preserve or not. If you want replacement, use the Polish books tool instead, which IIRC changes both the actual image and its wrapper HTML

[Lukusaukko]

I tested this with a PG book, and looks like Polish Books tool does add preserveAspectRatio inside the SVG tag, but sets the value to "none", and there are no configuration options to change this behaviour. Oh well, I just have to remember to do it by hand when I edit the books for reading - I hardly ever read anything without customizing it first in any case.

[kovidgoyal]

The value used by Polish books is customizable via Preferences->Output options->EPUB output->Preserve cover aspect ratio.

[Lukusaukko]

Originally Posted by kovidgoyal

The value used by Polish books is customizable via Preferences->Output options->EPUB output->Preserve cover aspect ratio.

Great! Thank you - I was looking for configuration options in the Plugin manager. I think I've noticed the option in that place before, but didn't connect it with Polish Books, thinking it was only for conversion settings (which Polish Books actually does, now that I think of it - it converts EPUB into polished EPUB).