Calibre tags and Moonreader Pro

[AdrianJ]

Hi All,
Have been using Calibre for quite a while, and recently added a whole lot of my own tags to books, in place of the publisher-generated ones. All looks good in Calibre.
I then use Calibre Sync to make my library available on a Boox Page ebook reader, which also works fine, and allows to sort and filter books using the tags in inserted in Calibre.

But when I import the the book(s) into Moonreader Pro, I notice that it seems to pick up a whole lot of tags from somewhere, useless ones like H001347 or other stuff I never inserted from Calibre. I checked a couple of books ( all ePub format ) with the calibre editor, and those tags dont appear anywhere within the ePub files, so MoonReader must be picking them up from somewhere else.

Anyone else seen this ? Its a bit of a nuisance, and defeats the purpose of the tags as a way of selecting books.
I realise I can select just a single book using Calibre Sync, and open it with Moonreader, but sometimes its more convenient to use Moonreader itself to select books from its bookshelf.

Comments welcome.

[chaley]

Moonreader gets the tags from inside the book's OPF, not calibre's database. If you use calibre's "send to device" or "save to disk" commands to copy the format to your device then calibre updates the book. If you do anything else, such as copying the book out of the library using calibre sync, then you must update the book yourself before doing the copy. You can do that with the "polish" or the "embed metadata" tools.

[enuddleyarbl]

The Modify ePub plugin has an option to Remove non dc: metadata elements (bottom-right option in its menu). I think that should delete those.

[AdrianJ]

Thanks enuddleyarbl, that plugin worked perfectly to remove the junk.
I had already looked both in the opf file and right through all the files in the epub using Calibre search for some of the weird tags, and not found them. They certainly arent in the <subject> tag of the opf file.
But the plugin you mentioned did work.
Its still a mystery ( to me ) where those extra tags are stored.

[BetterRed]

Originally Posted by AdrianJ

. . .

Its still a mystery ( to me ) where those extra tags are stored.

The Sigil EPUB editor has a metadata editor feature in it's Tools menu, it might provide a clue.

BR

[AdrianJ]

Thanks BetterRead
I looked in the epub file of a book which has this problem, using both Calibre and Sigil editors. The offending tags are not found. And yet MoonReader digs them up from somewhere when I add the book ( in epub format ) to its bookshelf on an Android tablet

Ah! I think I see what happens.
I originally got the book in .mobi format ( which does contain those odd tags) , converted it to .epub format, and used the Calibre metadata editor to replace the tags. I then copied the book from my main Calibre library to another library, the one I use to source books from Calibre Sync via a cloud server. Calibre copies both the .epub and the original .mobi file to the new library, but I dont send the .mobi files on to the cloud server I use. But that of course leaves the metadata.db file with the original mobi data and file references. Those then get picked up by MoonReader and shown. Interestingly they are not shown by the Calibre Sync filtering and selection system.

I guess it depends where the various programs pick up the metadata from, the original .epub file, the metadata.opf file for that book, or the Calibre metadata.db file for the entire library.

It would be useful if one could set the Calibre library copy function to send only books of a specific fomat to another library, like you can do with the disk file copy function.

Think I will ignore Moonreaders bookshelf, and just use Calibre Sync to select the book I want to read. That works perfectly.