Originally Posted by chaley
Intentionally no. I didn't (and don't) want to deal with the consequences of someone pushing Mark All then Delete, then having an oh-dear moment (in polite language).
In your case, IIRC the jpgs created by calibre2opds have a distinctive name that was not cover.jpg. Search for that name in the library using Windows Explorer and delete them there. That is what I did when I had the same problem, the need to clean up after switching from calibre2opds to my own web server. The obligatory warning: look at the results of the search before selecting all and hitting the delete key.
Great idea - yes these .jpgs do have a name called resizedcover.jpg - these are the ones I want removed so your idea is a really good one.
BTW, THANK YOU all for answering my question with good suggestions. I appreciate it.