MobileRead Forums - View Single Post - How are kobo books stored?

mylesau · 06-04-2010, 07:48 PM

I'm not sure why they did it, but some of the 'free 100' books (Gutenburg) are actually encrypted and some aren't.

The overuse of the "content" table to store both the book (ContentType = 6) and each of it's 'ShortCovers' (ContentType = 9) is odd to me - it would have made more sense to store these in separate tables, but perhaps there are limitations on the device or some performance gain to do it this way.

It looks to me that the IsEncrypted field has no meaning for the book (ContentType = 6) as they are all set to false, but only has meanings for the 'ShortCovers' (ContentType = 9) where they are set either to true or false which is then reflected in the 'shortcover_page' table with encrypted or plain text.

I think it would still be of value to be able to 'extract' the epub of an unencrypted book, and certainly of value to be able to 'dump' a single book or selection of books out, encrypted or not, for either backup purposes or perhaps to be able to import back into another Kobo.

06-04-2010, 07:48 PM	#6
mylesau Enthusiast Posts: 30 Karma: 12 Join Date: May 2010 Device: Kobo	I'm not sure why they did it, but some of the 'free 100' books (Gutenburg) are actually encrypted and some aren't. The overuse of the "content" table to store both the book (ContentType = 6) and each of it's 'ShortCovers' (ContentType = 9) is odd to me - it would have made more sense to store these in separate tables, but perhaps there are limitations on the device or some performance gain to do it this way. It looks to me that the IsEncrypted field has no meaning for the book (ContentType = 6) as they are all set to false, but only has meanings for the 'ShortCovers' (ContentType = 9) where they are set either to true or false which is then reflected in the 'shortcover_page' table with encrypted or plain text. I think it would still be of value to be able to 'extract' the epub of an unencrypted book, and certainly of value to be able to 'dump' a single book or selection of books out, encrypted or not, for either backup purposes or perhaps to be able to import back into another Kobo.