CALIBRE 0.8.8 VS COVERS ON KOBO TOUCH

[theducks]

Originally Posted by PeterT

Nada... no one has mentioned a similar problem there.

Well, the only other thing I can think of is to have some other Kobo touch owner that also uses Calibre on the Same OS (and cpu chip if 64 bit) try the failing file.

[PeterT]

I would but it would be my wife's Touch I only have a WiFi.... Now if we can wait till my birthday .....

[PeterT]

Jack.. please come back and describe the problem again, and include as much detail as possible... What ePubs have you had the problem on, what O/S etc.

[DoctorOhh]

Originally Posted by CazMar

I don't want to get into a slanging match - but I can see Jack has deleted his original thread in disgust.

He deleted his original post after post 5 was written. If he deleted it in disgust it was because of posts 2-5 and for the life of me I can't see any reason in those early posts to delete the details of the problem.

Originally Posted by CazMar

Perhaps some people should READ the threads before replying. The original question was a problem connected with the covers after loading the new version of Calibre

Everyone who read this thread after post 5 read a thread which does not have any details of a problem about kobo covers. The title could refer to any of a 100 threads complaining in the past about kobo covers. Not exactly something that would lend any hint of how we could help him.

Originally Posted by CazMar

If you can't reply politely, don't bother. I normally would not respond but this is about the 3rd time I have had rude and dismissive replies to a fairly neutral statement or question, something I would never do to even the most "newby" member of this group.

You might want to take your own advice and read the thread from the beginning (without and details in post 1) in context. you might see that there was no one in this thread being rude or dismissive until this post.

It isn't your fault, for some reason jackastor deleted the first post and changed the context for everyone who read the thread after post 5. If jackastor is still having troubles hopefully he will take PeterT's advice so we can help solve this problem.

[HarryT]

Jack has created another thread for the issue:

https://www.mobileread.com/forums/sho...d.php?t=141361

in which I've suggested a likely cause for the problem (that the cover isn't actually ending up in the book), but he's not yet replied to my post.

[chaley]

Originally Posted by HarryT

Jack has created another thread for the issue:

https://www.mobileread.com/forums/sho...d.php?t=141361

in which I've suggested a likely cause for the problem (that the cover isn't actually ending up in the book), but he's not yet replied to my post.

Other than with "hmmmmm".

[Starson17]

Originally Posted by dwanthny

Everyone who read this thread after post 5 read a thread which does not have any details of a problem about kobo covers.

That describes me. I read every post here, but couldn't see any discussion of a problem about kobo covers. I saw several posts about how to tell if the most recent update had fixed a problem with kobo covers and a post stating emphatically that this thread had nothing to do with updates - it had to do with kobo covers (which caused me to go back and read the posts again and decide that whatever this thread was about, it didn't describe a problem with kobo covers.)

[JSWolf]

Originally Posted by jackastor

so long and thanks for all the fish.

Thanks much for deleting your original post and causing no end of confusion for the rest of this thread.

[Kolenka]

Originally Posted by HarryT

Jack has created another thread for the issue:

https://www.mobileread.com/forums/sho...d.php?t=141361

in which I've suggested a likely cause for the problem (that the cover isn't actually ending up in the book), but he's not yet replied to my post.

Well, I've noticed some interesting cover behavior with the Kobo (which is nearly identical to the Sony in this area), and how Calibre generates covers.

Calibre can do one or two things:
- Update the meta tag in the OPF for the cover image itself.
- Insert an HTML cover page at the front of the ePub.

The Kobo, like the Sony, ignores the meta tag, and instead uses a rendering of the "cover" page from the ePub. It seems like there are quite a few situations where Calibre won't replace the existing cover page, and rightfully so. That said, I've had Calibre refuse to replace a cover page it created and had some odd/blank covers due to the size of the cover image and not using SVG to scale the image. I have one which simply shows a blank cover which I can always poke at tonight since I was going to fix the ePub anyways.

[jackastor]

Originally Posted by Kolenka

Well, I've noticed some interesting cover behavior with the Kobo (which is nearly identical to the Sony in this area), and how Calibre generates covers.

Calibre can do one or two things:
- Update the meta tag in the OPF for the cover image itself.
- Insert an HTML cover page at the front of the ePub.

The Kobo, like the Sony, ignores the meta tag, and instead uses a rendering of the "cover" page from the ePub. It seems like there are quite a few situations where Calibre won't replace the existing cover page, and rightfully so. That said, I've had Calibre refuse to replace a cover page it created and had some odd/blank covers due to the size of the cover image and not using SVG to scale the image. I have one which simply shows a blank cover which I can always poke at tonight since I was going to fix the ePub anyways.

Are you suggesting the issue is with the Kobo and not Calibre or a combination of both? So in an ideal world what would be the best settings for the cover genration then in Calibre? All the covers that I have had issue with are always located in the thumbnail view of the device via Calibre. But it seems when the unit disconnects the cover is tossed away by Kobo Touch and a blank cover is created in ints place and shown in the thumbnail view on Caliber when you look at the sd or main storage area. But if I open the book thats on the Kobo via Calibre the cover is shown in all its glory.

So what would be a workaround if one could? Any thing I have done seems to have random results. Sometimes it takes but most times it does not. Can never reproduce things twice in a row.

regards

Jack

[Kolenka]

It is a combination of both. Calibre uses a meta tag to find the cover, as does iTunes and the nook. The Kobo and Sony both use ADE's cover renderer which renders the first page of the ePub. There is one way to create the cover page which will render right for ADE/Sony/Kobo, but Calibre will not mess with the cover page in an ePub if one is already present. It's pretty easy to make a cover page that won't render right. I've got a few I did by hand a couple years ago that are mostly white space, only show the upper left corner of the cover, and one or two with a blank cover.

The way to fix it is explode the ePub and fix the cover page manually. You can also make sure this is your problem by loading the ePub into ADE on your computer and seeing what it shows as the cover.

[beachbunny]

I have a kobo wifi and had a similar problem not to long ago and it stemmed from a corrupted database on the KOBO ... I needed to restore the database for the Thumbnails of the books to show properly again. If you have alot of books loaded you may want to go the route of Kolenka has mentioned first ... In my case all the books listed after the corrupted record did not show the thumbnail properly. Another thing to try is forcing a hard reboot of the device ... for the WIFI version it is a matter of holding down the power button for 8 seconds this will cause the o/s to reload.

[DoctorOhh]

Originally Posted by Kolenka

Well, I've noticed some interesting cover behavior with the Kobo (which is nearly identical to the Sony in this area), and how Calibre generates covers.
...~~~...
The Kobo, like the Sony, ignores the meta tag, and instead uses a rendering of the "cover" page from the ePub.

You sum up this problem nicely. The main difference between the Sony devices and Kobo devices in reference to covers and calibre is the device driver for the Sony is more elaborate and has options to handle the covers. Fortunately there were developers that had the time and interest to enhance the Sony device driver when the x50 series was released.

[jackie_w]

Originally Posted by dwanthny

You sum up this problem nicely. The main difference between the Sony devices and Kobo devices in reference to covers and calibre is the device driver for the Sony is more elaborate and has options to handle the covers. Fortunately there were developers that had the time and interest to enhance the Sony device driver when the x50 series was released.

Regarding the Sony x50s, it took quite a while to discover why the Sony kept throwing away what looked like perfectly good Calibre thumbnails. You could see them appear then disappear before your very eyes as the Sony chose to extract its own thumbnail from page 1 of the book.

The answer appeared, as if by magic, one day when chaley was adding a Sony thumbnail enhancement I'd requested. It turned out that the Sony wanted its thumbnails to be a particular size. Once they were, all thumbnail problems disappeared...

I wonder if there's a magic Kobo requirement no one has discovered yet?

[jackastor]

Originally Posted by Kolenka

It is a combination of both. Calibre uses a meta tag to find the cover, as does iTunes and the nook. The Kobo and Sony both use ADE's cover renderer which renders the first page of the ePub. There is one way to create the cover page which will render right for ADE/Sony/Kobo, but Calibre will not mess with the cover page in an ePub if one is already present. It's pretty easy to make a cover page that won't render right. I've got a few I did by hand a couple years ago that are mostly white space, only show the upper left corner of the cover, and one or two with a blank cover.

The way to fix it is explode the ePub and fix the cover page manually. You can also make sure this is your problem by loading the ePub into ADE on your computer and seeing what it shows as the cover.

So Kolenka What is the right way to make the cover then? Whats the magic? And incidently on my own books they all show the covers correctly in ADE, Caliber and Iphone just not so on the Kobo Touch. I am beginning to suspect its corruption somewhere somehow.

regards

jack