Dealing with Kindle for PC/Mac 1.19 and KFX in calibre

[salamanderjuice]

Originally Posted by Lief

And I think there is already a issues open for this problem (not by me) :
https://github.com/noDRM/DeDRM_tools/issues/57

It's a problem with a broken book(s). I've run into the same issue where the "advanced.opf" is missing in a few of my titles and Calibre can't open the file or process it's metadata. Some ePub readers don't care like Thorium or ADE and will happily ignore it. Others like Koreader will read the metadata but can't open the file and some like Calibre can't do either. You can also just unzip the file and read the contents.

[DNSB]

Originally Posted by Katsunami

So this would remove DRM from books downloaded with ADE 3.0 and higher? That would be great. I wonder how NoDRM tested that. I've seen some posts around on different forums and sites where people say that this "has been working for some time", but it later turned out that they were just getting books with the old DRM in ADE 3.0 and up.

It seems the new DRM isn't used a lot, even though it has existed for... what... 8+ years?

As the person who cracked the new Adobe DRM commented, the hardest part was finding books that were encrypted using it.

Personally, I've only seen two non-textbooks that used the hardened encryption. Like Amazon and books that insist on using the newest KFX encryption, it seems to be more an issue for textbook vendors who need to charge higher prices to cover the smaller sales potential of their offerings.

[DNSB]

Originally Posted by ThatsANovelIdea

Sorry if I missed some context elsewhere (VERY long thread), but you didn't mention using Adobe Digital Editions in your steps. Are you saying you were able to circumvent the need for the Adobe Digital Editions program?

I read that there is a new Calibre plugin that eliminates the need for Adobe Digital Editions, but didn't know if that is what you're using..

The first part was about the hardened Adobe DRM now being decryptable. The second part was about books from Kobo downloaded using the Kobo desktop app. This uses Kobo's proprietary DRM which Obok will remove. Please note that Obok does not work for Kobo Plus books (since they are basically a borrowed book, that doesn't bother me).

And yes, I often use the DeACSM plugin to save me a step in downloading epubs and then importing them to calibre.

[DNSB]

Originally Posted by Lief

About the kobo ebook did you open the converted ebook? Because I did not get any error during conversion but the result was not readable in my case.

I opened the book and read a few pages using calibre's ebook-viewer.

Originally Posted by Lief

And I think there is already a issues open for this problem (not by me) :
https://github.com/noDRM/DeDRM_tools/issues/57

Looking at the issue, one poster mentions cancelling his Kobo subscription so I suspect that the book was a Kobo Plus offering which Obok will not decrypt. For the OP, given the epub structure error reported, the original download has been corrupted.

[ThatsANovelIdea]

Originally Posted by DNSB

The first part was about the hardened Adobe DRM now being decryptable. The second part was about books from Kobo downloaded using the Kobo desktop app. This uses Kobo's proprietary DRM which Obok will remove. Please note that Obok does not work for Kobo Plus books (since they are basically a borrowed book, that doesn't bother me).

And yes, I often use the DeACSM plugin to save me a step in downloading epubs and then importing them to calibre.

Ah, understood. If you're open to some usability questions...

What do you find yourself preferring/using more: Kobo desktop app -> Obok OR Kobo website -> Adobe Digital Editions/DeASCM -> import into Calibre?

Are there situations or use cases where you find yourself using one over the other more often? Any issues with using one where you've found that the other covers it? Ever notice any quality differences in the resulting files between the two?

[JSWolf]

Originally Posted by ThatsANovelIdea

Ah, understood. If you're open to some usability questions...

What do you find yourself preferring/using more: Kobo desktop app -> Obok OR Kobo website -> Adobe Digital Editions/DeASCM -> import into Calibre?

Are there situations or use cases where you find yourself using one over the other more often? Any issues with using one where you've found that the other covers it? Ever notice any quality differences in the resulting files between the two?

I prefer using ADE and then import into Calibre. That way I have a DRM free ePub.

[Sirtel]

Originally Posted by JSWolf

I prefer using ADE and then import into Calibre. That way I have a DRM free ePub.

I download the epub from the Kobo website and use the deACSM plugin + Calibre.

[ThatsANovelIdea]

Originally Posted by JSWolf

I prefer using ADE and then import into Calibre. That way I have a DRM free ePub.

Oh, I thought the Obok plugin would also output a DRM-free .epub file? (Never used it before - still in the middle of trying to setup everything I need/want.)

Does it output a different file format?

[DNSB]

Originally Posted by ThatsANovelIdea

Ah, understood. If you're open to some usability questions...

What do you find yourself preferring/using more: Kobo desktop app -> Obok OR Kobo website -> Adobe Digital Editions/DeASCM -> import into Calibre?

Are there situations or use cases where you find yourself using one over the other more often? Any issues with using one where you've found that the other covers it? Ever notice any quality differences in the resulting files between the two?

Generally, I prefer the Kobo Desktop app => Obok => calibre, the second choice is to download the DRM free ebubs with their odd names and the .acsm files for the DRMmed epubs and the add both them into calibre. Using ADE is pretty much a last choice these days.

I've found little to make either epub or kepub my preferred choice. At one time, I did some testing and could not find a renderer where the reading was noticeably affected by the <span koboid> items in a kepub.

[Lief]

Originally Posted by salamanderjuice

It's a problem with a broken book(s). I've run into the same issue where the "advanced.opf" is missing in a few of my titles and Calibre can't open the file or process it's metadata. Some ePub readers don't care like Thorium or ADE and will happily ignore it. Others like Koreader will read the metadata but can't open the file and some like Calibre can't do either. You can also just unzip the file and read the contents.

Originally Posted by DNSB

I opened the book and read a few pages using calibre's ebook-viewer.

Looking at the issue, one poster mentions cancelling his Kobo subscription so I suspect that the book was a Kobo Plus offering which Obok will not decrypt. For the OP, given the epub structure error reported, the original download has been corrupted.

Like I said in my last post I actually solved my problem by closing the Kobo app after the download or by downloading an ebook (not manga/comics).
For some strange reason (probably a different bug), Obok will see a manga/comic digital drm-free even when it's not until you close the app after the download or until you download a book.
So my problem was not the file or the drm removal from Obok, my problem was in the first step, Obok saw a drm-free file so it didn't try to decrypt it, after I closed the Kobo app (or after I downloaded one of my book) it saw the file as drm so it succeded in removing the drm.
I'm talking about a bought manga/comic of course

Originally Posted by ThatsANovelIdea

Oh, I thought the Obok plugin would also output a DRM-free .epub file? (Never used it before - still in the middle of trying to setup everything I need/want.)

Does it output a different file format?

the output is .epub for both. They read the same in calibre. For what I understand the Obok epub is actually a kepub that's not 100% epub open standard.
That's usually not an issue and you will be able to convert it to a standard epub if you need to.
The real reason to keep it both is to use them when one of them does not work anymore even temporaly (since they are different kind of drm that's possible).

[lkmiller]

One of the reasons I like buying from Kobo is that there are two potential ways of freeing my books. I usually use ADE and DeDRM, but I check every once in a while that my Kobo/Obok setup is still good. There have been a couple ocassions when there was an issue with getting the ADE epub. So I've grabbed the book from Kobo Desktop or directly from my Kobo with Obok.

[JSWolf]

Originally Posted by ThatsANovelIdea

Oh, I thought the Obok plugin would also output a DRM-free .epub file? (Never used it before - still in the middle of trying to setup everything I need/want.)

Does it output a different file format?

What I would do is download the .acsm file to ADE and then import the ePub to strip the DRM. If I wanted to read KePub, I would use the KoboTouchExtended driver to convert to KePub when sending to the Kobo from Calibre.

But I don't read KePub much so I want ePub and I use the ePub renderer (RMSDK) or KOReader to read the ePub.

[JSWolf]

Originally Posted by Lief

The output is .epub for both. They read the same in calibre. For what I understand the Obok epub is actually a kepub that's not 100% epub open standard.
That's usually not an issue and you will be able to convert it to a standard epub if you need to.
The real reason to keep it both is to use them when one of them does not work anymore even temporaly (since they are different kind of drm that's possible).

The file you get using Obok is KePub and on a Kobo, KePub and ePub do not always read the same. That's why you should try both and decide which you prefer.

[Lief]

Originally Posted by JSWolf

The file you get using Obok is KePub and on a Kobo, KePub and ePub do not always read the same. That's why you should try both and decide which you prefer.

What I said is that the KePub you get is still a .epub file that you can convert to a regular epub with calibre.

[DNSB]

Originally Posted by JSWolf

The file you get using Obok is KePub and on a Kobo, KePub and ePub do not always read the same. That's why you should try both and decide which you prefer.

Given that an ebook imported into calibre using OBOK only has the .epub extension, it's going to be hard to see any differences. BTW, ModifyEpub will removed the extra spans.

Perhaps you should make it clear that on a Kobo, there are two renderers, one being RMSDK which is used for .epub books and one based on webkit/Readium which is used for .kepub.epub books. The webkit renderer also handles much more of the epub3 standard including being able to render fixed layout epubs. Since you are using two different renderers, expecting the books to appear identical is not a realistic expectation.

For a real test, try renaming filename.kepub.epub to filename.epub and see if RMSDK shows any noticeable differences between the two versions.

The first block is prior to running ModifyEpub, the second block is post.

<body>
  <div xmlns="http://www.w3.org/1999/xhtml" id="book-columns">
    <div xmlns="http://www.w3.org/1999/xhtml" id="book-inner">
      <h1 id="chap6" class="center"><span xmlns="http://www.w3.org/1999/xhtml" class="koboSpan" id="kobo.1.1">5</span></h1>

      <p class="noind" style="margin-top:30px;"><span xmlns="http://www.w3.org/1999/xhtml" class="koboSpan" id="kobo.2.1">W</span><small><span xmlns="http://www.w3.org/1999/xhtml" class="koboSpan" id="kobo.3.1">HEN THEY RETURNED, BRASS</span></small><span xmlns="http://www.w3.org/1999/xhtml" class="koboSpan" id="kobo.4.1"> called, “Good news! </span><span xmlns="http://www.w3.org/1999/xhtml" class="koboSpan" id="kobo.4.2">We got who we wanted.”</span></p>
      <p class="ind"><span xmlns="http://www.w3.org/1999/xhtml" class="koboSpan" id="kobo.5.1">“Crew’s coming along,” commented Calli.</span></p>

<body>
  <div xmlns="http://www.w3.org/1999/xhtml" id="book-columns">
    <div xmlns="http://www.w3.org/1999/xhtml" id="book-inner">
      <h1 id="chap6" class="center">5</h1>

      <p class="noind" style="margin-top:30px;">W<small>HEN THEY RETURNED, BRASS</small> called, “Good news! We got who we wanted.”</p>

      <p class="ind">“Crew’s coming along,” commented Calli.</p>