Clara HD Some questions how Nickel works internally

[brettonwoods]

Hi there,

I recently got a Kobo Clara HD and running latest firmware (4.25.15875 11/9/20).

As a "newbie" I have a few questions about how Nickel (the default reader?) works internally:

After a factory reset I put all my books in a folder "books" in the root path (of the sd card). After unmounting the reader, Nickel is importing the books.

*Question 1: How does the import process work ?*

Does Nickel automatically (constantly) look for new "book" files every time the device is unmounted?


*Question 2: How to fix "Authors" ?*

in "My Books -> Authors" I see the books listed by author. How exactly is the author extracted from the books, that is, which file type and meta data field is being used?

I'm currently using only .epub and .pdf files. Some author names are wrong. I wonder how to fix them, i.e. .epub files with Sigil editor. Which field is expected to contain the author name and in which format exactly?


*Question 3: How are books managed "internally" ?*

After updating meta data in one of my .epub files using Sigil (trying to fix the author) I synced the "books" folder, using the command "rsync -av src dest". After unmounting the kobo device it imports the books again, and I now see them twice (!) in the "My Books -> Books" section.

How exactly does the import process work? Does it import the files entirely in the sqlite3 database? Which table? How come I am now seeing them double?
And how can I fix this issue?


*Question 4: Where are highlights and annotations stored ?*

Are they also stored in the sqlite database? How can I export them? I saw that with "KoReader" they are stored in an extra .sdr folder which seems much easier to preserve and backup.


Thank you very much for your effort and patience to read this and your feedback.

BW

[davidfor]

Originally Posted by brettonwoods

Hi there,

I recently got a Kobo Clara HD and running latest firmware (4.25.15875 11/9/20).

As a "newbie" I have a few questions about how Nickel (the default reader?) works internally:

After a factory reset I put all my books in a folder "books" in the root path (of the sd card). After unmounting the reader, Nickel is importing the books.

*Question 1: How does the import process work ?*

Does Nickel automatically (constantly) look for new "book" files every time the device is unmounted?

Nickel looks for changes in the books everytime you eject the device.

*Question 2: How to fix "Authors" ?*

in "My Books -> Authors" I see the books listed by author. How exactly is the author extracted from the books, that is, which file type and meta data field is being used?

I'm currently using only .epub and .pdf files. Some author names are wrong. I wonder how to fix them, i.e. .epub files with Sigil editor. Which field is expected to contain the author name and in which format exactly?

The title, author etc. are extracted from the metadata in the book. If you edit the book and set the metadata correctly, it will be read when you import it. If you use Sigil, it has a metadata editor which will make it pretty obvious where the author goes.

If the book doesn't have any metadata, or is a format that does not contain metadata, the file name is used for the title and the author is "Unknown" or something like that.

*Question 3: How are books managed "internally" ?*

After updating meta data in one of my .epub files using Sigil (trying to fix the author) I synced the "books" folder, using the command "rsync -av src dest". After unmounting the kobo device it imports the books again, and I now see them twice (!) in the "My Books -> Books" section.

How exactly does the import process work? Does it import the files entirely in the sqlite3 database? Which table? How come I am now seeing them double?
And how can I fix this issue?

That means you put a new copy of the book on the device with a different file name. The file name and path is used by the internal database as the key. The device has no issued with two books with identical metadata but different file locations.

To fix, just remove the book you don't want.

*Question 4: Where are highlights and annotations stored ?*

Are they also stored in the sqlite database? How can I export them? I saw that with "KoReader" they are stored in an extra .sdr folder which seems much easier to preserve and backup.

The annotations are stored in the database. There is a lot of discussion about how to get them out of the database. A search will find it. And the details haven't changed for a while.