Little bit confused about Kepub conversion in Calibre

jaceneliot · 08-23-2020, 06:36 AM

Hello.

I'm a bit lost in relation to the different extensions that allow to automatically convert EPUB to KEPUB. For a while, it worked well, when I clicked on "send to device", it sent a Kepub automatically. The series, authors, descriptions, playback percentage, playback time, special features worked well.

But now, 1/2, when I send an ebook, it's in Epub. Sometimes they are in Kepub but don't have all the features. Finally, last problem, I noticed a problem with a book in Kepub, while the problem doesn't exist with the same one in Epub. It is the Integral of "The Witcher". It's a very big ebook. The problem is this: some chapters (about one chapter out of four or five) is cut in two. Basically, it says something like "34/35 pages in the chapter". But when I get to the end of the chapter, I'm actually still in the same chapter. The reader makes a page break and the chapter continues, but the reader calls it a new chapter. That's okay, but it bugs me.

All this to say that there seems to be a problem with my conversion to Kepub. Here are my extensions on the picture.

In the end, my question is this: which extensions are necessary (and which ones are useless) to properly send Kepub? Which are the most reliable extensions, and which ones to remove? I use "Kobo Utilities" features. The rest, I'm not sure.

Thanks in advance!

davidfor · 08-23-2020, 08:43 AM

If your only trying to get kepub to the device, then you probably just want the KoboTouchExtended driver. You need to make sure it is enable, and, you should disable the built-in KoboTouch driver. This can be done on the Plugins page of the preferences.

In the configuration of the driver, you need to makes sure that "Enable Extended Kobo Features" is enabled in the "Extended" tab.

With this when you send a book to the device, the extended driver will do the work to transform it into a kepub.

It is possible for the transformation to kepub to kepub to fail. The driver has an option to ignore the failures and send the epub as is. If this happens, it usually means there is an error in the epub that needs to be fixed. If you open it in the calibre editor, you can use the error checking to show the problems and fix them.

Your chapter problem with the Witcher book is almost definitely in the source book. The creator has probably split some longer chapters. This is because some ereaders have problems with internal files longer than this. A conversion in calibre usually does this if an internal file is longer than 260KB. The extended driver does not do this, it des not change the internal file structure of the book.

As to which of the plugins are reliable, they all are. They just do different things. The Kobo Output plugin is not needed if you don't convert books to kepub using a conversion. The Kobo Input plugin is used if you have kepubs in your library and want to convert them to other formats. The Kepub Metadata Writer and Kepub Metadata Reader are used to update and read metadata from kepubs respectively. They are mainly needed if you are keeping kepubs in your calibre library. Finally, the Kobo Books metadata source plugin is to fetch metadata from the Kobo store for books.

Which of the plugins you install and use depends on what you want to do. You can happily use none. Or all.

theducks · 08-23-2020, 11:49 AM

I suspect your book is made up of 1 or a couple of huge (x)HTML files with the CSS doing a Logical PageBreak at each chapter

Until it reaches a certain size (260K was the Calibre default, safer for for older devices), Then the file was split at the closest Paragraph.

(FWIW The Quality Check Plugin has a Check Structure: Check for Oversized Files check. Unfortunately it can't COUNT how many HTML files make up the book (a low number would be a clue that the Size Break method was enforced). AFAIK Only looking at the structure of the book (eg Calibre Editor: Reports, or the list in the Book Browser) will tell you how many files (segments) are really there.

Looking at the LINK code in the TOC would give you a clue (assumes a full TOC): If the same file appears many times and it just uses an Anchor (#nnnn) to jump, you are using CSS forced breaks
My personal choice is to split the file by chapters (and join the broke-up chapter).
Hopefully you know (or are willing to learn) Basic e-book HTML (all you need for most fiction)

khoogeland · 03-06-2023, 02:37 PM

Just letting you know that this helped me out in 2023. I could not figure out why KoboTouchExtended didn't want to turn my epub into a kepub. Turns out that splitting the large tables it contained (long epic poem, 2000 lines per table) solved the problem. It's large files that were the clue, here. Thanks!

08-23-2020, 06:36 AM	#1
jaceneliot Junior Member Posts: 8 Karma: 10 Join Date: May 2018 Device: Kobo H2O 2 Edition	Little bit confused about Kepub conversion in Calibre Hello. I'm a bit lost in relation to the different extensions that allow to automatically convert EPUB to KEPUB. For a while, it worked well, when I clicked on "send to device", it sent a Kepub automatically. The series, authors, descriptions, playback percentage, playback time, special features worked well. But now, 1/2, when I send an ebook, it's in Epub. Sometimes they are in Kepub but don't have all the features. Finally, last problem, I noticed a problem with a book in Kepub, while the problem doesn't exist with the same one in Epub. It is the Integral of "The Witcher". It's a very big ebook. The problem is this: some chapters (about one chapter out of four or five) is cut in two. Basically, it says something like "34/35 pages in the chapter". But when I get to the end of the chapter, I'm actually still in the same chapter. The reader makes a page break and the chapter continues, but the reader calls it a new chapter. That's okay, but it bugs me. All this to say that there seems to be a problem with my conversion to Kepub. Here are my extensions on the picture. In the end, my question is this: which extensions are necessary (and which ones are useless) to properly send Kepub? Which are the most reliable extensions, and which ones to remove? I use "Kobo Utilities" features. The rest, I'm not sure. Thanks in advance! Attached Thumbnails

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08-23-2020, 08:43 AM	#2
davidfor Grand Sorcerer Posts: 24,905 Karma: 47303822 Join Date: Jul 2011 Location: Sydney, Australia Device: Kobo:Touch,Glo, AuraH2O, GloHD,AuraONE, ClaraHD, Libra H2O; tolinoepos	If your only trying to get kepub to the device, then you probably just want the KoboTouchExtended driver. You need to make sure it is enable, and, you should disable the built-in KoboTouch driver. This can be done on the Plugins page of the preferences. In the configuration of the driver, you need to makes sure that "Enable Extended Kobo Features" is enabled in the "Extended" tab. With this when you send a book to the device, the extended driver will do the work to transform it into a kepub. It is possible for the transformation to kepub to kepub to fail. The driver has an option to ignore the failures and send the epub as is. If this happens, it usually means there is an error in the epub that needs to be fixed. If you open it in the calibre editor, you can use the error checking to show the problems and fix them. Your chapter problem with the Witcher book is almost definitely in the source book. The creator has probably split some longer chapters. This is because some ereaders have problems with internal files longer than this. A conversion in calibre usually does this if an internal file is longer than 260KB. The extended driver does not do this, it des not change the internal file structure of the book. As to which of the plugins are reliable, they all are. They just do different things. The Kobo Output plugin is not needed if you don't convert books to kepub using a conversion. The Kobo Input plugin is used if you have kepubs in your library and want to convert them to other formats. The Kepub Metadata Writer and Kepub Metadata Reader are used to update and read metadata from kepubs respectively. They are mainly needed if you are keeping kepubs in your calibre library. Finally, the Kobo Books metadata source plugin is to fetch metadata from the Kobo store for books. Which of the plugins you install and use depends on what you want to do. You can happily use none. Or all.

08-23-2020, 11:49 AM	#3
theducks Well trained by Cats Posts: 30,447 Karma: 58055868 Join Date: Aug 2009 Location: The Central Coast of California Device: Kobo Libra2,Kobo Aura2v1, K4NT(Fixed: New Bat.), Galaxy Tab A	I suspect your book is made up of 1 or a couple of huge (x)HTML files with the CSS doing a Logical PageBreak at each chapter Until it reaches a certain size (260K was the Calibre default, safer for for older devices), Then the file was split at the closest Paragraph. (FWIW The Quality Check Plugin has a Check Structure: Check for Oversized Files check. Unfortunately it can't COUNT how many HTML files make up the book (a low number would be a clue that the Size Break method was enforced). AFAIK Only looking at the structure of the book (eg Calibre Editor: Reports, or the list in the Book Browser) will tell you how many files (segments) are really there. Looking at the LINK code in the TOC would give you a clue (assumes a full TOC): If the same file appears many times and it just uses an Anchor (#nnnn) to jump, you are using CSS forced breaks My personal choice is to split the file by chapters (and join the broke-up chapter). Hopefully you know (or are willing to learn) Basic e-book HTML (all you need for most fiction)

03-06-2023, 02:37 PM	#4
khoogeland Junior Member Posts: 8 Karma: 10 Join Date: Jul 2010 Location: Amsterdam Device: Kobo Sage/ Kobo Elipsa	Just letting you know that this helped me out in 2023. I could not figure out why KoboTouchExtended didn't want to turn my epub into a kepub. Turns out that splitting the large tables it contained (long epic poem, 2000 lines per table) solved the problem. It's large files that were the clue, here. Thanks!