MobileRead Forums - View Single Post

unboggling · 12-03-2013, 03:24 PM

The OPF is mainly for calibre to use as a backup if you ever have to restore the database.

The metadata resides in the backend database tables and is stored in file metadata.db.

As I understand it, conversion or export (save, send, email, get from content server) update some metadata internal to the book format, depending on the type of format, of the exported or converted copy, but not in the original base format the convert or export used to make the copy. Polish Books (EPUB or AZW3 only) or plugin Modify ePub (EPUB only) can update metadata in the base format without a conversion.

In preferences for Saving to disk, there is a tick box to save the OPF file along with the book, or not.

12-03-2013, 03:24 PM	#3
unboggling Wizard Posts: 1,065 Karma: 858115 Join Date: Jan 2011 Device: Kobo Clara, Kindle Paperwhite 10	The OPF is mainly for calibre to use as a backup if you ever have to restore the database. The metadata resides in the backend database tables and is stored in file metadata.db. As I understand it, conversion or export (save, send, email, get from content server) update some metadata internal to the book format, depending on the type of format, of the exported or converted copy, but not in the original base format the convert or export used to make the copy. Polish Books (EPUB or AZW3 only) or plugin Modify ePub (EPUB only) can update metadata in the base format without a conversion. In preferences for Saving to disk, there is a tick box to save the OPF file along with the book, or not. Last edited by unboggling; 12-03-2013 at 04:53 PM. Reason: clarification per BetterRed in #5 on polish & mod epub.