Mobi - missing opf files

[nemo1966]

Hi, first post new Kindle user

On buying my wife a new Kindle a couple of weeks ago I was given a collection of books in MOBI format (approx 10,000 with no drm). GREAT! However being a Software Developer by profession I noticed that some came with a matching jpg (cover) and a opf file. I have looked up the description of the OPF file and it goes something like this

Open Packaging Format. It is what is known as a build file. The Kindlegen program will use the .opf file to call the other files to generate the .mobi file for your ebook.

Initial Questions:
1) Do I need the opf file? if so can I recreate it from the .mobi file?
2) If I have a jpg and opf file and don't copy them to the kindle do I lose anything? will it give me errors?

Seeing as I have so many titles I was thinking if cataloging them to a searchable database - obviously it would be good to be able to search by genre, author, title etc etc (see where I'm going yet?) well this brings me back to the missing opf file that seems to contain all this information in a neat package... but many of my files again have a missing opf file. This then brings me back to recreation of this file or ripping the information directly from the mobi file. As it stands all the information I have for many mobi files is the author and title as these are contained in the file name.

Can anyone help? Any information/clarification would be greatly appreciated.

regards
Steve

[HarryT]

You don't need the OPF file - it's contained within the book. Likewise the JPG - it's presumably just a cover image, which again is contained within the book.

Do take care: there are a lot of illegal eBooks floating around and I'm sure that you don't want to break the law. Many (perhaps even most) of these book "collections" are blatantly illegal, pirated material. As a reader I'm sure that you'd want to support authors by buying their books.

As far as cataloging and maintaining your books goes, you can't do better than "Calibre", which is free, and supported in its own forum right here at MR.

[nemo1966]

Originally Posted by HarryT

You don't need the OPF file - it's contained within the book. Likewise the JPG - it's presumably just a cover image, which again is contained within the book.

Do take care: there are a lot of illegal eBooks floating around and I'm sure that you don't want to break the law. Many (perhaps even most) of these book "collections" are blatantly illegal, pirated material. As a reader I'm sure that you'd want to support authors by buying their books.

As far as cataloging and maintaining your books goes, you can't do better than "Calibre", which is free, and supported in its own forum right here at MR.

Thanks for the info - I didn't know Calibre was that involved, I will look onto it.

Regards
Steve