There are two different issues here - the resolution size of the image file and the size that the client uses to display it.
In calibre2opds there is an option to specify the cover height. If you are not using Calibre cover images directly then resized cover images will be generated to this resolution.
An OPDS client decides how to size the cover image for display purposes although it may take notice of the resolution supplied by calibre2opds. Different OPDS clients seem to take different approaches. In the HTML catalogs the browser is instructed explicitly to display cover images at the size specified in the calibre2opds settings.
|