Kobo Bug thread

[Nick_1964]

Originally Posted by davidfor

And yes, I am being obtuse in my comments. But, as someone who has spent a very large percentage of their career fixing software bugs or other problems with computers, I don't want to hear "It doesn't work". I want to hear how it doesn't work and how it should work. And I want to hear that in excruciating detail.

That is the only good way to do it !
I gonna look for a topic that explains what a kepub is, what advantage it is to epub, and how to convert it.

[bobb40]

Originally Posted by davidfor

It would be a good idea to describe what you think is wrong.

It's described in post 418 of this forum. Calibre viewer renders the pages correctly.

How do you "partially convert a kepub"? Does it involve Calibre?

[davidfor]

Originally Posted by bobb40

It's described in post 418 of this forum. Calibre viewer renders the pages correctly.

So it was. Looking at the post, I remember reading it but didn't pay much attention. A link back to that post and a comment that the attached epub was a simple test case would have been good. A description of what you expected with this test case would still have been good.

How do you "partially convert a kepub"? Does it involve Calibre?

No, simply renaming the file to have the double-extension ".kepub.epub" will get it treated as a kepub. It will display correctly but any bookmarks won't point to the correct place and it won't display the correct cover. Calibre plus some plugins will do the full conversion as we understand them.

[Lucas Malor]

Originally Posted by davidfor

I sideloaded as a kepub. I just added the ".kepub" into the name instead of doing the full conversion. Both pages look how I think you mean for them to look. And they agree with what the calibre viewer displays.

I think this means the problem is in the RMSDK. Which means it will be up to Adobe (or whoever maintains it now) to fix.

Ehi, good job as usual, David. It was a good idea to confront epub reader vs kepub one.

I do not understand why Kobo continues to use the Adobe's renderer for epubs, for which I suppose they paid much money, instead of using its own reader, that is better and faster.
Since kepub is epub plus some modification, I think kepub reader can render epubs with only a little modification. So why? Maybe kepub does not support Adobe's DRM system and they decided to not use kepub reader for all epubs for simplicity? Company policies are still obscure to me

[davidfor]

Originally Posted by Lucas Malor

I do not understand why Kobo continues to use the Adobe's renderer for epubs, for which I suppose they paid much money, instead of using its own reader, that is better and faster.
Since kepub is epub plus some modification, I think kepub reader can render epubs with only a little modification. So why? Maybe kepub does not support Adobe's DRM system and they decided to not use kepub reader for all epubs for simplicity? Company policies are still obscure to me

I am sure that the Adobe DRM is the problem. I don't think that Adobe have licensed this in any way that can be used with another reading system.

[bobb40]

Originally Posted by davidfor

A link back to that post and a comment that the attached epub was a simple test case would have been good.

Such comment has been added.

Originally Posted by davidfor

No, simply renaming the file to have the double-extension ".kepub.epub" will get it treated as a kepub. It will display correctly but any bookmarks won't point to the correct place and it won't display the correct cover.

That's a neat trick, but it doesn't give EPUBs full reader capability. KoboGlo support of EPUB is crippled, and should be fixed; else, they should stop claiming to support EPUB.

[davidfor]

Originally Posted by bobb40

That's a neat trick, but it doesn't give EPUBs full reader capability.

What is missing? The reader used for kepubs is ACCESS. That has very good epub3 support and I thought it also did good epub2 support.

KoboGlo support of EPUB is crippled, and should be fixed; else, they should stop claiming to support EPUB.

But probably no worse than any other Adobe RMSDK based ereader. I just looked back at your photos. The only other e-ink ereader is a Kindle, and it's support for epub2 is a LOT worse than any Kobo ereader.

And looking at those photos/screenshots, ADE is conspicuous by it's absence. It is the de facto standard reader for epubs.

[Lucas Malor]

Ah, I thought Kobo did it. This Publus Reader (ex NetFront BookReader) is almost unknown. It will be interesting to do a Wikipedia comparison page for epub readers.

[speakingtohe]

Originally Posted by davidfor

What is missing? The reader used for kepubs is ACCESS. That has very good epub3 support and I thought it also did good epub2 support.


But probably no worse than any other Adobe RMSDK based ereader. I just looked back at your photos. The only other e-ink ereader is a Kindle, and it's support for epub2 is a LOT worse than any Kobo ereader.

I must respectfully disagree. I have had many books (over 1,000) that would not display well on the Kobo(s). Double/triple line spacing being the most notable, but weird font sizes, odd indentations, one line per page quite common All of these books displayed just fine on various Sony readers and on the kindle (my mothers) after converting to mobi. The majority of these books were originally .lrf. .lit or B&N epubs. Converting these books to mobi and then back to epub seems to 'fix' them so they can be read on the Kobo(s).

Several days ago I tried reading a book on my Aura HD and it would open to the cover. Any attempt to go further resulted in a return to the main page. Tried touching, swiping, TOC, slide bar, slide bar arrows etc.
Same book works perfectly on my T3.

So why do you think the Adobe engine is less functional on the Kobo? Lot of Kobo readers out there and Adobe gets the same financial return from Kobo as from Sony I assume. Does not seem likely that Adobe is providing an inferior engine. And not because it is an older version of said engine I am sure as old Sony readers (before Kobo even sold readers) display epubs more reliably.

Helen

[Lucas Malor]

It's definitively an Adobe Digital Editions bug. I downloaded it, installed and opened your testcase, the text is completely messed up. Probably the other ereader companies uses the ADE SDK to workaround its bugs.

Try to report it to the ADE forum. I suggest you to not mention Kobo, or you'll be ignored. Report it simply as an ADE bug and link the testcase. In the end, this _is_ an ADE bug.

[DNSB]

Originally Posted by speakingtohe

I must respectfully disagree. I have had many books (over 1,000) that would not display well on the Kobo(s). Double/triple line spacing being the most notable, but weird font sizes, odd indentations, one line per page quite common All of these books displayed just fine on various Sony readers and on the kindle (my mothers) after converting to mobi. The majority of these books were originally .lrf. .lit or B&N epubs. Converting these books to mobi and then back to epub seems to 'fix' them so they can be read on the Kobo(s).

Common complaint about Kobo actually using the embedded styles while other ereaders seem to disregard the embedded style and use a generic stylesheet. The only time I've had that issue on legitimate epubs (not from the result of converting other formats to epub), the issue was traceable to styles that the Kobo was trying to display as intended.

Originally Posted by speakingtohe

Several days ago I tried reading a book on my Aura HD and it would open to the cover. Any attempt to go further resulted in a return to the main page. Tried touching, swiping, TOC, slide bar, slide bar arrows etc.
Same book works perfectly on my T3.

The only times I've seen that on my collection of Kobo ereaders is when I manually deleted the ebook from my computer's file explorer and then replaced it with a new copy. Using either Calibre or the Kobo GUI to delete a book has not caused the problem -- so far. My opinion is this issue is due to the database not being cleaned up so the new copy is using the old book's information.

Try deleting the book using either Calibre or the Kobo GUI and then reloading it to see if it now works.

Originally Posted by speakingtohe

So why do you think the Adobe engine is less functional on the Kobo? Lot of Kobo readers out there and Adobe gets the same financial return from Kobo as from Sony I assume. Does not seem likely that Adobe is providing an inferior engine. And not because it is an older version of said engine I am sure as old Sony readers (before Kobo even sold readers) display epubs more reliably.

I've compared a couple of other ereaders including a Sony and an Ectaco to Kobos. What I can say is that Kobo displayed the ebook's styling including wide margins and line spacing correctly even when that correctness was a pain to try to read. On one ebook, the margins on the Kobo were ~2cm wide and the lines were double spaced with ~1cm gaps between paragraphs. Looking at the stylesheets (6 of them plus an Adobe page-template.xpgt!) in the epub after removing the DRM, that was exactly what the publisher (Bloombury) intended. Trying to read a page using the same screen real estate as the book cover uses when sleeping in non-fullscreen mode is not "A GOOD IDEA" in my not so humble opinion.

I won't get started on stylesheet that use points (talk about relics from dead tree books) or pixels for absolute sizing rather than % or em to allow scaling.

Regards,
David

[DNSB]

Originally Posted by bobb40

With the demise of the Sony reader, and the unavailability and uncertainty of the Nook, Kobo readers have become the leading eink devices for reading EPUBs.

The Kobo specification page for the Glo (https://www.kobo.com/koboglo/techspecs/) proclaims:


The Kobo devices are listed by Wikipedia and other references as capable of reading EPUB.

But the spec for EPUB 2.0.1 (http://idpf.org/epub/201) and OPS (http://www.idpf.org/epub/20/spec/OPS_2.0.1_draft.htm), clearly states "OPS Reading Systems must support SVG [except animation and scripting features]". And "rotate" and "dy" are among the basic attributes of SVG. So if SVG's "rotate" and "dy" are not supported, EPUB is not supported.

Attached is a bare-minimum EPUB "KoboGlo Bug Demo" which passes epubcheck:

- dogmatix:fix> /usr/local/bin/run_epubcheck kgbd.epub
- Epubcheck Version 3.0.1
-
- Validating against EPUB version 2.0
- No errors or warnings detected.

This EPUB demonstrates SVG's "rotate" and "dy". It is a simple test case for post 418 on this forum. It displays normally on most EPUB readers, but demonstrates faults of KoboGlo.

Ummm... I loaded your test case file in ADE both on a Mac using OS X 10.9 and a Windows computer (Win7 SP1, x64). The display for the dy was crap on both.

I've attached a screen shot of ADE displaying the dy page which, oddly enough, looks pretty much identical to what I see on my Aura using the Adobe RMSDK though forcing use of the ACCESS renderer does seem to display the pages properly -- see the screen captures for those as well.

Regards,
David

[speakingtohe]

Originally Posted by DNSB

Common complaint about Kobo actually using the embedded styles while other ereaders seem to disregard the embedded style and use a generic stylesheet. The only time I've had that issue on legitimate epubs (not from the result of converting other formats to epub), the issue was traceable to styles that the Kobo was trying to display as intended.



The only times I've seen that on my collection of Kobo ereaders is when I manually deleted the ebook from my computer's file explorer and then replaced it with a new copy. Using either Calibre or the Kobo GUI to delete a book has not caused the problem -- so far. My opinion is this issue is due to the database not being cleaned up so the new copy is using the old book's information.

Try deleting the book using either Calibre or the Kobo GUI and then reloading it to see if it now works.



I've compared a couple of other ereaders including a Sony and an Ectaco to Kobos. What I can say is that Kobo displayed the ebook's styling including wide margins and line spacing correctly even when that correctness was a pain to try to read. On one ebook, the margins on the Kobo were ~2cm wide and the lines were double spaced with ~1cm gaps between paragraphs. Looking at the stylesheets (6 of them plus an Adobe page-template.xpgt!) in the epub after removing the DRM, that was exactly what the publisher (Bloombury) intended. Trying to read a page using the same screen real estate as the book cover uses when sleeping in non-fullscreen mode is not "A GOOD IDEA" in my not so humble opinion.

I won't get started on stylesheet that use points (talk about relics from dead tree books) or pixels for absolute sizing rather than % or em to allow scaling.

Regards,
David

Book was just put on, but I will try deleting it and putting it on again.

I also have a hard time understanding why a publisher, Barnes and Noble for example, would intend a book to have/display spaces between each and every line several times the height of the characters.

I don't pretend to understand how renderers work. I have the impression due to people saying it is the Adobe engine responsible for rendering epubs, that it is (the renderer) somewhat independent. But others seem to indicate that reader manufacturers/developers have quite a bit of control. Perhaps you could explain which is right if you have time.

And yes I have seen some ugly books, many of which are not displayed well by any reader/app/program. Even some books available on overdrive leave a lot to be desired. Generally I can fix them and I am not overly fussy.

But I have seen many more that display just fine on other readers, programs, apps. In fact they closely mimic a paper book. Why have there not been big protests from publishers when these books are displayed with normal spacing, consistent margins etc. if they were intended to be displayed with the big gaps and other peculiarities?

I am obviously missing the big picture

Helen

[Rev. Bob]

Originally Posted by speakingtohe

I also have a hard time understanding why a publisher, Barnes and Noble for example, would intend a book to have/display spaces between each and every line several times the height of the characters.

(snip)

But I have seen many more that display just fine on other readers, programs, apps. In fact they closely mimic a paper book. Why have there not been big protests from publishers when these books are displayed with normal spacing, consistent margins etc. if they were intended to be displayed with the big gaps and other peculiarities?

Part of it may be that you appear to have confused publishers with stores; B&N doesn't care what the books you buy from them look like, as they have no control over that. As for publishers' apathy, most of the complaints go to the stores, which have no reason to pass them along. Besides, by that time they already have your money; why would they worry about changing the book? What are you going to do, not buy a second copy?

Basically, I'm saying that ebooks don't work better due to widespread apathy, lack of investment in ebooks as a proper platform, and misdirected complaints. Get the complaints to the right places, and maybe things will change.

[Lucas Malor]

Originally Posted by speakingtohe

I don't pretend to understand how renderers work. I have the impression due to people saying it is the Adobe engine responsible for rendering epubs, that it is (the renderer) somewhat independent. But others seem to indicate that reader manufacturers/developers have quite a bit of control. Perhaps you could explain which is right if you have time.

I quote myself

Originally Posted by Lucas Malor

It's definitively an Adobe Digital Editions bug. I downloaded it, installed and opened your testcase, the text is completely messed up. Probably the other ereader companies uses the ADE SDK to workaround its bugs.