Page turns increment current page by 2

[tiltowait]

This has been going on for years. With my sideloaded kepubs, the page numbers are wrong. Going to the next page increases the current page number by roughly 2.2 (it’s displayed as an integer; around every 5 page turns or so increases by 3 instead of 2). Naturally, this means the book’s total size is listed as twice its actual length.

It only affects the "overall" page count; pages within the chapter are the expected 1:1.

I'm using a Forma with 4.34.20097. I've been sending the kepubs via KTE in Calibre. I tried creating the kepubs with kepubify instead, to the same result.

I do have a few patches enabled:

libnickel.so.1.0.0.yaml
* Replace adobe page numbers toggle with invert screen
* Swap reading header/footer
* Set KePub hyphenation

nickel.yaml
* Increase home screen cover size
* Increase library cover size
* Reduce new header/footer height
* Increase size of kepub chapter progress chart
* Increase Book Details synopsis area

I also have JSWolf's hyphenation patch, and I have "optimizelegibility" set in the configuration file living in .kobo/Kobo. Disabling optimizelegibility does not fix it.

My next port of call will be to install factory firmware (no patches) and see if it's still happening. If that fixes it, I will re-enable patches one-by-one until I find the culprit.

However! If someone knows off-hand what the issue is, that would be great (and save me some time). Thanks.

[Aleron Ives]

You specifically say "sideloaded" KEPUB. Does this mean you don't observe the same behaviour with KEPUB that you sync directly from Kobo? I've noticed that the main menu will indicate that there are 3 pages left in a chapter, when there is in fact only one page left, so I assumed that the page counter was just inaccurate. I don't use the header or footer to track page progress all the time, though.

[tiltowait]

Good question! I don't normally read books purchased on the Kobo store, but I just downloaded one to test. It seems to exhibit the same behavior, although less constant. In other words, it might go 60, 61, 62, 64, 66, 67, 69, 71, 73, 74 ...

[tiltowait]

And now I have updated to factory 4.35.20400, and my Forma still exhibits the same behavior.

[rashkae]

The page numbers for the whole book are a best guess estimate, so it's normal to have a few page turns not count 100%... but I've never seen it this wildly off. Strange that it's happening to *all* your books and not just a specific one. Were the original epubs all from the same source?

[JSWolf]

KePub is not exactly a 1-1 page count. It's been that way for some time.

[tiltowait]

Hm, that's a shame. How is it able to give accurate numbers for the current chapter but not the entire book?

[JSWolf]

Originally Posted by tiltowait

Hm, that's a shame. How is it able to give accurate numbers for the current chapter but not the entire book?

Because it's coded that way.

[rashkae]

Originally Posted by tiltowait

Hm, that's a shame. How is it able to give accurate numbers for the current chapter but not the entire book?

Every time you adjust font size, (or magins, or line height, etc.), you have to paginate the entire document to calculate the page breaks. A single chapter, (which is an individual file within the epub, and is already opened and parse din memory) can be done in seconds. To do the whole book could take minutes.

[John F]

Originally Posted by rashkae

Every time you adjust font size, (or magins, or line height, etc.), you have to paginate the entire document to calculate the page breaks. A single chapter, (which is an individual file within the epub, and is already opened and parse din memory) can be done in seconds. To do the whole book could take minutes.

That could be done in the background?

Or once they have calculated a chapter, they could update the total page count.