kepubify v3: A fast, standalone EPUB to KEPUB converter (plus covergen/seriesmeta)

[Gibbo]

Originally Posted by geek1011

You can use the ARM binaries in Termux (you'll need to run termux-setup-storage to get access to your files).

Sounds too complicated

[JSWolf]

delete post

[Brain]

Does using this tool preserve image quality? Right now I have to choose to either read an epub without ability to zoom in or convert it to kepub (calibre plugin) and experience diminished image quality when I zoom in.

[JSWolf]

Originally Posted by Brain

Does using this tool preserve image quality? Right now I have to choose to either read an epub without ability to zoom in or convert it to kepub (calibre plugin) and experience diminished image quality when I zoom in.

In your output profile, set it to Tablet. That will keep the images at the original size.

[geek1011]

Originally Posted by Brain

Does using this tool preserve image quality? Right now I have to choose to either read an epub without ability to zoom in or convert it to kepub (calibre plugin) and experience diminished image quality when I zoom in.

kepubify is not the same as the Calibre plugin...

[Brain]

Originally Posted by JSWolf

In your output profile, set it to Tablet. That will keep the images at the original size.

I wasn't able to find that option so far. Could you direct me there step-by-step, please?

Originally Posted by geek1011

kepubify is not the same as the Calibre plugin...

Sure. I'm not implying that. I am asking to know if it's a worthy alternative.

[davidfor]

Originally Posted by Brain

I wasn't able to find that option so far. Could you direct me there step-by-step, please?

When you do a conversion, go to the "Page setup" tab and choose "Tablet" in the "Output profile" list.

But, I would recommend doing this in the preferences on the "Common options" page. That will set the defaults for all new conversions.

Sure. I'm not implying that. I am asking to know if it's a worthy alternative.

Yes, it is. But, kepubify is probably better compared to using the KoboTouchExtended driver. That transforms an epub during the send to device. It doesn't run the full calibre conversion process. For most people, using the KoboTouchExtended driver is better than doing a conversion to kepub. Or use kepubify.

[Brain]

Originally Posted by davidfor

When you do a conversion, go to the "Page setup" tab and choose "Tablet" in the "Output profile" list.

But, I would recommend doing this in the preferences on the "Common options" page. That will set the defaults for all new conversions.


Yes, it is. But, kepubify is probably better compared to using the KoboTouchExtended driver. That transforms an epub during the send to device. It doesn't run the full calibre conversion process. For most people, using the KoboTouchExtended driver is better than doing a conversion to kepub. Or use kepubify.

Thank you! I found the option. Admittedly the second paragraph at the moment goes over my head. I'll probably get it later when I read more about it.

[twowheels]

I tend to manage my library manually, mostly using Calibre for its command line tools, and for that reason I personally find kepubify a worthy alternative. Not sure if you're a terminal user, but I wrote an alias named "tokobo" that sends an epub to my kobo as a kepub, tokobo is aliased to `kepubify -o /Volumes/KOBOeReader'

(that target path is for MacOs, for Linux it would be something like /media/$USER/KOBOeReader, and for Windows it'd be a drive letter, like E. I then just run it at the terminal, something like this:

$ tokobo MyBook.epub

I've found the conversions to be perfect for my needs, but I'm not nearly as concerned about the details, such as custom CSS, perfect metadata, etc, as some people here.

[davidfor]

Originally Posted by Brain

Thank you! I found the option. Admittedly the second paragraph at the moment goes over my head. I'll probably get it later when I read more about it.

At the moment, there are three ways to produce a kepub:

• A conversion in calibre. This uses the full conversion pipeline. It will mean a lot of changes are made in the book. This can include rewriting the stylesheet, reformatting the book, rebuilding the ToC, resizing the images and a lot more. It will also add the converted kepub to the calibre library. To get this onto the device, you need to send it from calibre.
• The KoboTouchExtended driver. This copies the epub and adds the necessary spans to it plus a few other changes necessary for the book to work as an epub. It doesn't do any of the other changes mentioned above. When these changes are made, the kepub is sent to device. It makes no changes to the calibre library.
• Using kepubify. This also works on a copy of an epub. It makes the same sort of changes as the KoboTouchExtended driver. The kepub can be sent to the device or put somewhere else to be used later.

The best choice from the above is up to you. If you are a calibre user, then the KoboTouchExtended driver is the simplest choice. But, it will transform all epubs to kepubs when they are sent to the device. If you don't want to read everything as a kepub, then you might be better doing the conversion to kepub. This allows you to convert books where the kepub features are useful (especially images and footnotes) but stick with epubs for other books. If you are not a calibre user, then kepubify makes sense.

I probably should say that by "calibre user", I am meaning someone that uses calibre to manage their library. While @twowheels uses calibre, they are using it as part of their toolset and managing their books some other way. And kepubify is also in their toolset.

I am definitely a "calibre user". I manage my library using it and manage my devices as well. I tend to use epubs, but, also read kepubs for books I have purchased from Kobo. I do sideload as kepub sometimes. I usually turn the KoboTouchExtended driver on when I do this, but, I do have plenty of books I have converted to kepub in my library.

[geek1011]

Originally Posted by davidfor

The best choice from the above is up to you. If you are a calibre user, then the KoboTouchExtended driver is the simplest choice. But, it will transform all epubs to kepubs when they are sent to the device. If you don't want to read everything as a kepub, then you might be better doing the conversion to kepub. This allows you to convert books where the kepub features are useful (especially images and footnotes) but stick with epubs for other books. If you are not a calibre user, then kepubify makes sense.

One small thing to add: kepubify is slightly better at not making books with malformed or unusual HTML worse, but the full Calibre conversion attempts to fix that sort of thing (that may be for better or for worse depending on the situation). Calibre is better at fixing malformed TOCs and that sort of thing, and kepubify is better at preserving the original code where possible. Basically, if you encounter formatting issues not in the original EPUB, try using the other converter and see if the problem is still there.

[davidfor]

Originally Posted by geek1011

One small thing to add: kepubify is slightly better at not making books with malformed or unusual HTML worse,

Better than what? You mean the KoboTouchExtended driver? The driver shouldn't make things worse. If it can't do something, it should stop and show an error or send the epub untouched, depending on the option. It does have some error handling, but the stated aim was to transform valid epubs.

But, I am curious to see examples that it makes the HTML worse. If you have some, can you send them to me?

but the full Calibre conversion attempts to fix that sort of thing (that may be for better or for worse depending on the situation). Calibre is better at fixing malformed TOCs and that sort of thing, and kepubify is better at preserving the original code where possible. Basically, if you encounter formatting issues not in the original EPUB, try using the other converter and see if the problem is still there.

I don't compare what a conversion does to what either the extended driver or kepubify does. Both of these are assuming a working epub as input. Both do attempt to handle problems, but, to different extents. The extended driver doesn't touch the ToC, only the actual text files. And a few things in the OPF.

The conversion is just assuming an input book. It doesn't have to be epub. And the output is largely what would have been seen with a conversion to epub and then the spans added. If this fails, it will be because the input file was rubbish.

[geek1011]

Originally Posted by davidfor

But, I am curious to see examples that it makes the HTML worse. If you have some, can you send them to me?

I was referring to things like the recent bug with whitespace (this, IIRC), this one with <br/> tags, and this one with tag ordering. Both of these have been fixed in KTE, but kepubify doesn't have that kind of problem as often since it does more using a normal HTML parser, then outputs valid polyglot XHTML+HTML4+HTML5 no matter what the original was (but it does preserve XML declarations). It's not so much that it makes the HTML worse as that it's processing method is more bug-prone.

Kepubify will also handle EPUB3 HTML5 auto-closing tags correctly (it will close them rather than nest everything after it) (remember that a document like <!DOCTYPE html><html lang="en"><title>Document</title><meta charset="utf-8"><div>test</div><p>paragraph<p><i>another</i> is valid HTML5).

The anything->XHTML+HTML4+HTML5 conversion plus that kepubify parses the HTML as HTML means that it is generally a bit more consistent with browser engine-based renderers wrt parsing bad HTML. I don't have a specific example of this right now, but I've seen a few of these before.

One theoretical example I haven't seen in the wild would be the use of regexps vs the actual tree when cleaning up tags. Basically, this bug would cause issues if there were missing closing tags, it wouldn't remove them if they were self closing (possibly due to processing as pure XML using another tool), and if there happened to be a script dealing with these as strings.

There are also a few differences in span processing like this.

I don't have these issues myself since I usually regenerate the HTML code for my books when I get them. I have a small script which essentially extracts paragraphs and things, converts it to an internal format similar to FB2, then back to EPUB.

The conversion is just assuming an input book. It doesn't have to be epub. And the output is largely what would have been seen with a conversion to epub and then the spans added. If this fails, it will be because the input file was rubbish.

Yes, that's correct. Many people seem to expect it not to touch that kind of thing, though.

[JSWolf]

Does KoboTouchExtended hande KF8 eBooks?

[davidfor]

Originally Posted by JSWolf

Does KoboTouchExtended hande KF8 eBooks?

It explicitly only handles epubs. Which I stated above more than once.

But, as it is in the standard send-to-device pipeline, if you do not have a format that the device accepts, calibre will convert the book to a supported format. Then it will send the book at which point the KoboTouchExtended driver will step in. Assuming that the format calibre converted the book to is epub. But, it could have been another format depending on your configuration.

And this is way of topic for this thread. If you need to discuss it more, start a thread in the calibre forum, or post in the KoboTouchExtended thread. But, first read the calibre manual about send-to-device.