Full-screen cover when sleeping with ePub?

Antioch · 01-19-2022, 12:52 AM

Hello! I'm a long-time ePub user and have heard that using kePubs will allow the book's cover image to be displayed full-screen when the Kobo is sleeping rather than with white borders as it does with ePubs.

I prefer to use ePubs rather than kePubs, but I'm wondering if there is any method (firmware patch? alternative reader?) that will allow the ePub covers to be displayed full-screen when sleeping?

davidfor · 01-19-2022, 06:23 AM

Sorry, but none of that is correct. If anything, it is backwards. In fact, the cover image for an epub always fills the screen. The problem you are seeing is not where you think it is. The issue is how the cover images are generated for each format.

For sideload kepubs, the image to be used as a cover is marked in the OPF. The device will extract the image and resize it as needed. It does not change the aspect ratio. That means when it is displayed on the sleep screen, it is shown with with borders unless the cover is the same aspect ratio as the screen. For purchased books, the covers are downloaded from the Kobo server but otherwise treated the same.

For epubs, the device renders the start of the book and takes the first page as the cover. That means that whatever you see as the first page when you open the epub will be the cover image. And that includes whatever letterboxing or stretching is done to any image in the page. It also means that if the first page is just text, then the cover image used will be that text.

The above is the reason I say that the information you have is wrong. Unless the image in the kepub has the same aspect ratio as the screen, you will have borders. And for epubs, the borders are not added to the cover image when it is displayed, but, they are in the book.

The fix for epubs is to change the code on the page that displays the cover to fill the screen. This will probably mean the image will be distorted as it will probably have to be stretched to fill the screen. How to do this depends on what tools you use for ebooks and your familiarity with the code in them.

For kepubs, you would need to resize the image to the aspect ratio of the screen before putting it in the cover. Again, this will result in a distorted image.

Alternatively, if you are a calibre user, you can have calibre generate and send the covers to the device when sending the books. There driver has options to do this. For books already on the device, you can use my Kobo Utilities plugin to replace the covers.

There may be a patch to force the device to do this, at least for kepubs, but, I don't remember seeing one.

ZodWallop · 01-19-2022, 09:47 AM

Quote:

Originally Posted by davidfor

For sideload kepubs, the image to be used as a cover is marked in the OPF. The device will extract the image and resize it as needed. It does not change the aspect ratio. That means when it is displayed on the sleep screen, it is shown with with borders unless the cover is the same aspect ratio as the screen.

I have many (most?) books on my Clara where the aspect ratio doesn't match the screen. When I open the book, the cover will be letterboxed or pillarboxed. But on the sleep screen the cover is stretched to fill the screen. See attached for an example. (Please forgive the glare and slight fisheye I always get when taking a close-up picture.)

John F · 01-19-2022, 10:37 AM

Quote:

Originally Posted by ZodWallop

I have many ( most?) books on my Clara where the aspect ratio doesn't match the screen. When I open the book, the cover will be letterboxed or pillarboxed. But on the sleep screen the cover is stretched to fill the screen. See attached for an example. (Please forgive the glare and slight fisheye I always get when taking a close-up picture.)

Interesting. I just tried it, and my sideloaded kepub was pillarboxed on the sleep screen.

And in addition to % read, it also shows time remaining. I am on a newish firmware.

ZodWallop · 01-19-2022, 11:09 AM

Quote:

Originally Posted by John F

Interesting. I just tried it, and my sideloaded kepub was pillarboxed on the sleep screen.

And in addition to % read, it also shows time remaining. I am on a newish firmware.

I'm on 4.30.18838.

In Settings/Energy saving and privacy, I have Show current read, Show book covers full screen , Show info panel on full screen covers all checked.

Show book covers full screen is probably what is different between you and me. Is yours checked?

I think in settings there's the option of what to show on the info panel, or maybe that's in a patch? I don't remember as I never mess with it.

John F · 01-19-2022, 11:35 AM

Quote:

Originally Posted by ZodWallop

I'm on 4.30.18838.

In Settings/Energy saving and privacy, I have Show current read, Show book covers full screen , Show info panel on full screen covers all checked.

Show book covers full screen is probably what is different between you and me. Is yours checked?

I think in settings there's the option of what to show on the info panel, or maybe that's in a patch? I don't remember as I never mess with it.

I have the same firmware version and options checked that you mentioned. Are you sure you are sideloading kepubs? Also, my kepubs are sideloaded on the fly.

I do patch, but nothing related to the sleep screen.

ZodWallop · 01-19-2022, 01:41 PM

Quote:

Originally Posted by John F

I have the same firmware version and options checked that you mentioned. Are you sure you are sideloading kepubs? Also, my kepubs are sideloaded on the fly.

I am 100% certain.

Did a little diving and found this old thread I started years ago: Stretch the cover to fit the screen?

davidfor · 01-19-2022, 07:04 PM

Quote:

Originally Posted by ZodWallop

I am 100% certain.

Did a little diving and found this old thread I started years ago: Stretch the cover to fit the screen?

And from that, you are sending the covers from calibre with the option "Keep cover aspect ratio" not checked. Which is what I refer to in the second last paragraph of my post.

If that is not the case, then I don't know how you have managed it. What I stated has been the case for all the time I have been using Kobo devices. And is still the case with the firmware I am using now.

John F · 01-20-2022, 06:49 AM

Any guesses as to why ZodWollop's isn't showing time remaining? Maybe because he hasn't gone past the cover page?

davidfor · 01-20-2022, 06:58 AM

Quote:

Originally Posted by John F

Any guesses as to why ZodWollop's isn't showing time remaining? Maybe because he hasn't gone past the cover page?

That seems to be it. I just opened a book and put it to sleep without turning a page and it showed 1% with no time remaining.

ZodWallop · 01-20-2022, 08:22 AM

Quote:

Originally Posted by John F

Any guesses as to why ZodWollop's isn't showing time remaining? Maybe because he hasn't gone past the cover page?

Maybe. The book in my example was one I opened because I knew the aspect ratio was different.

I use a sleepcover and don't usually see the sleep screen. Let me open the book I'm about to start and flip a few pages in to see if it shows time remaining...

Edit: As per the attached, looks like you are right.

As you might have noticed, I'm working my way through Harold Bloom's Western Canon

Antioch · 01-23-2022, 12:09 AM

Quote:

Originally Posted by davidfor

Sorry, but none of that is correct. If anything, it is backwards. In fact, the cover image for an epub always fills the screen. The problem you are seeing is not where you think it is. The issue is how the cover images are generated for each format.
...
For epubs, the device renders the start of the book and takes the first page as the cover. That means that whatever you see as the first page when you open the epub will be the cover image.
...
Alternatively, if you are a calibre user, you can have calibre generate and send the covers to the device when sending the books. There driver has options to do this. For books already on the device, you can use my Kobo Utilities plugin to replace the covers.

Thank you for the information! That explains a lot about the behavior I observed. I never thought to think that it was the first page of the epub that was displayed.

I will try using caliber to generate/send the covers (I don't think I've ever enabled anything but barebones settings).

Thank you, again.

Nightflyer · 01-23-2022, 07:57 AM

I read the title of this thread and thought you were looking for a cover to protect your screen in case you rolled over on it in bed.

Epubs, I only use epubs and the cover fills the screen quite nicely. No margins. Only occasionally if some ePub is formatted incorrectly and then it might have margins or even be off-centered.

Also make sure to check the box to show book covers full screen

the.Mtn.Man · 01-23-2022, 12:03 PM

Quote:

Originally Posted by ZodWallop

(Please forgive the glare and slight fisheye I always get when taking a close-up picture.)

No! That is unforgivable!

Antioch · 01-24-2022, 08:10 AM

[deleted]

01-19-2022, 12:52 AM	#1
Antioch Connoisseur Posts: 79 Karma: 10 Join Date: Jun 2011 Device: Nook STR, Kobo Aura H2O, Kobo Libra 2	Full-screen cover when sleeping with ePub? Hello! I'm a long-time ePub user and have heard that using kePubs will allow the book's cover image to be displayed full-screen when the Kobo is sleeping rather than with white borders as it does with ePubs. I prefer to use ePubs rather than kePubs, but I'm wondering if there is any method (firmware patch? alternative reader?) that will allow the ePub covers to be displayed full-screen when sleeping?

01-23-2022, 07:57 AM	#13
Nightflyer Connoisseur Posts: 81 Karma: 2122502 Join Date: May 2020 Location: Asia (from USA) Device: Meebook M6, Kobo Clara HD	I read the title of this thread and thought you were looking for a cover to protect your screen in case you rolled over on it in bed. Epubs, I only use epubs and the cover fills the screen quite nicely. No margins. Only occasionally if some ePub is formatted incorrectly and then it might have margins or even be off-centered. Also make sure to check the box to show book covers full screen Last edited by Nightflyer; 01-23-2022 at 08:09 AM.

01-24-2022, 08:10 AM	#15
Antioch Connoisseur Posts: 79 Karma: 10 Join Date: Jun 2011 Device: Nook STR, Kobo Aura H2O, Kobo Libra 2	[deleted] Last edited by Antioch; 01-24-2022 at 08:18 AM.

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01-19-2022, 06:23 AM	#2
davidfor Grand Sorcerer Posts: 24,905 Karma: 47303824 Join Date: Jul 2011 Location: Sydney, Australia Device: Kobo:Touch,Glo, AuraH2O, GloHD,AuraONE, ClaraHD, Libra H2O; tolinoepos	Sorry, but none of that is correct. If anything, it is backwards. In fact, the cover image for an epub always fills the screen. The problem you are seeing is not where you think it is. The issue is how the cover images are generated for each format. For sideload kepubs, the image to be used as a cover is marked in the OPF. The device will extract the image and resize it as needed. It does not change the aspect ratio. That means when it is displayed on the sleep screen, it is shown with with borders unless the cover is the same aspect ratio as the screen. For purchased books, the covers are downloaded from the Kobo server but otherwise treated the same. For epubs, the device renders the start of the book and takes the first page as the cover. That means that whatever you see as the first page when you open the epub will be the cover image. And that includes whatever letterboxing or stretching is done to any image in the page. It also means that if the first page is just text, then the cover image used will be that text. The above is the reason I say that the information you have is wrong. Unless the image in the kepub has the same aspect ratio as the screen, you will have borders. And for epubs, the borders are not added to the cover image when it is displayed, but, they are in the book. The fix for epubs is to change the code on the page that displays the cover to fill the screen. This will probably mean the image will be distorted as it will probably have to be stretched to fill the screen. How to do this depends on what tools you use for ebooks and your familiarity with the code in them. For kepubs, you would need to resize the image to the aspect ratio of the screen before putting it in the cover. Again, this will result in a distorted image. Alternatively, if you are a calibre user, you can have calibre generate and send the covers to the device when sending the books. There driver has options to do this. For books already on the device, you can use my Kobo Utilities plugin to replace the covers. There may be a patch to force the device to do this, at least for kepubs, but, I don't remember seeing one.

01-20-2022, 06:49 AM	#9
John F Grand Sorcerer Posts: 7,852 Karma: 70186493 Join Date: Feb 2009 Device: Kobo Clara 2E	Any guesses as to why ZodWollop's isn't showing time remaining? Maybe because he hasn't gone past the cover page?

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