[Device Plugin] Kobo Touch Extended Driver

[davidfor]

Originally Posted by lumpynose

Thanks guys, now I'm more confused than I was previously.

I installed the Generate Cover plugin, which makes nice covers. But it only makes the jpg cover file and puts it in the folder that Calibre has the epub in. It doesn't modify the epub file and add the cover to it.

But the Kobo extended driver has the option for uploading covers, which I turned on. After uploading the book the epub file size on the Kobo is larger, and opening the epub on the Kobo with Sigil shows the cover.jpg file in the Images directory and Sigil says it's a Cover Image. But when I unplug the Kobo and open the epub on the Kobo with its ereader the margins are still hosed.

So then I tried using the Modify ePub plugin. It adds the image to the epub and also creates a titlepage.xhtml file and when that is sent to the Kobo everything is fine; no wacko margins. But there's an annoying waste of space with the Modify ePub plugin because it creates a copy of the cover.jpg named cover.jpeg, which is what it uses for the titlepage.xhtml file, and then it puts both cover.jpg and cover.jpeg in the Images folder in the epub.

KoboUtilities has a thing to clean the images directory of extra images but it doesn't affect the epub file. The Quality Check plugin has things for checking for missing covers but that only looks for the cover.jpg files in the folder the epub is in within Calibre's library.

So I'm somewhat mystified about the cover.jpg file in the Calibre folders. Apparently Calibre generates one when an epub is added (an epub that doesn't have a cover image) and uses the text from the first page or so.

I'm also wondering if you guys realized that it would be a two step process to properly add a cover with the titlepage.xhtml file, which solves the margin problem. Having an image marked as a cover is insufficient; it needs the titlepage.xhtml as well.

Actually, I never said to generate a cover. What I said was that Polish books or Modify ePub plugin would add the cover to the book. The assumption was that you already have a cover image in your calibre library. As you noticed, calibre will usually generate one from the book when you add it to the library. This could be using an image file in the book, or by rendering the first page and using it. For books formats don't have a cover, such as TXT files, they have to be sourced elsewhere. Or, the cover image can be added by other methods, such as the two cover generating methods mentioned, or using a metadata source plugin. And I assumed you would be doing the latter to get a decent cover image to display.

For the actual books, what is the cover depends on the format. And the reader device or app. The epub format, can define a cover image separately to what is shown when reading. It is very common that the cover image is shown on the first page. But, it isn't mandatory. Or, a different image could be used. The first page could be optimised for reading, and the cover image optimised for display elsewhere. On a Kobo ereader, for ePubs, the first page is used as the cover. For kepubs, it is the image marked as the cover in the OPF. Also, the epub or kepub is self-contained format. Everything is contained inside it. This includes the cover image if there is one.

For a kepub, there is also something else. The first file in the book is treated differently. It is treated as a fixed-layout. That is why you see the strange formatting when that first file just contains text.

The extended driver isn't going to add the cover. It assumes the book is ready to be transformed to a kepub and put on the device. And that means someone has thought about what is the cover and added it to the book. Once you have the cover added to the book in the library, the methods mentioned, conversion, Polish book and the Modify ePub plugin are all ways to add the cover to the book. Or you can edit the book and add the cover yourself. For an PG sourced book, splitting the first file so that the title is in a separate file at the start will probably work. Or adding an extra file with the title in text will work.

And the driver cover upload is separate again. That is there to send the cover image from the calibre library to the device rather than letting the device do its thing for generating a cover images. These cover images have nothing to do with reading the book. They are what are displayed in in the book lists, the book details page or the screensaver. It is also useful for the formats that do not contain something that can be used as a cover or cannot be updated with the cover.

[lumpynose]

Originally Posted by BetterRed

When I run Modify with Insert or replace cover checked I get a book with a cover page and ONE image file -- cover.jpeg.

BR

That's one of the things I tried last night but after I ran Modify ePub I'd open the epub in Sigil and Sigil always complained about cover.jpg or nav.xhtml not being in the manifest.

But of course I wasn't using a minimal epub, I was using one that I'd downloaded from Project Gutenberg.

I'll ask over in the Sigil forum why it's complaining. When I look at the content.opf there's a line for the nav.xhtml in the manifest section so it looks ok to me.

[lumpynose]

Originally Posted by davidfor

What I said was that Polish books or Modify ePub plugin would add the cover to the book.

Duh, sorry; I forgot about your suggestion to use Polish. On the positive side I got to play with the Generate Cover plugin. I like its covers better than the rendered text ones.

[theducks]

Originally Posted by lumpynose

That's one of the things I tried last night but after I ran Modify ePub I'd open the epub in Sigil and Sigil always complained about cover.jpg or nav.xhtml not being in the manifest.

But of course I wasn't using a minimal epub, I was using one that I'd downloaded from Project Gutenberg.

I'll ask over in the Sigil forum why it's complaining. When I look at the content.opf there's a line for the nav.xhtml in the manifest section so it looks ok to me.

I just ignore that (recent version) complaint. I know the books work before and after

[lumpynose]

Originally Posted by theducks

I just ignore that (recent version) complaint. I know the books work before and after

Ok thanks.

[lumpynose]

Originally Posted by davidfor

Actually, I never said to generate a cover. ...

So is it correct to say that the 3 likely scenarios are, 1) the book has no cover in the epub and calibre generates one from the initial text, 2) the book has a cover image, but it's not in an xhtml file that's tagged as the cover / title page, and 3) the book has a cover image and is in the cover /title page. With scenarios 2 and 3 calibre extracts the cover image and displays it when you're using its cover grid mode.

Scenarios 1 and 2 are where the margins are messed up but the epub can be transformed into scenario 3 by running Polish books or Modify ePub.

Short of opening each epub in calibre's editor, is there an easy way to differentiate between an epub in scenarios 2 and 3? Or can I run Polish books on all of them and ignore whatever state they're in? (Probably not a bad idea in general, in order to smarten the punctuation and other stuff.)

[jackie_w]

Originally Posted by lumpynose

Or can I run Polish books on all of them and ignore whatever state they're in? (Probably not a bad idea in general, in order to smarten the punctuation and other stuff.)

FWIW that's the first thing I do for every new book as far as the cover is concerned.

On the other hand I don't bulk Polish with Smarten Punctuation ever since the time I was on auto-pilot and smartened a programming book - completely wrecking the code samples.

[theducks]

Originally Posted by lumpynose

So is it correct to say that the 3 likely scenarios are, 1) the book has no cover in the epub and calibre generates one from the initial text, 2) the book has a cover image, but it's not in an xhtml file that's tagged as the cover / title page, and 3) the book has a cover image and is in the cover /title page. With scenarios 2 and 3 calibre extracts the cover image and displays it when you're using its cover grid mode.

Calibre ONLY automatically extracts a KNOWN cover when it ADDS.books
You can force this from inside the MDE (assumes there is a identified cover) from a selected format using the brown book icon next to the formats box

The Grid or Details or Info pane use the same cover (the one saved in the title folder), just scaled to meet the rules of the place shown.

[lumpynose]

Originally Posted by jackie_w

FWIW that's the first thing I do for every new book as far as the cover is concerned.

Ok, thanks. Good to know.

Originally Posted by jackie_w

On the other hand I don't bulk Polish with Smarten Punctuation ever since the time I was on auto-pilot and smartened a programming book - completely wrecking the code samples.

Yeah, that's like me when I do a search and replace in sigil and tell it to do it on all html files and it proceeds into the nav.xhtml and wrecks it.

[lumpynose]

Originally Posted by theducks

Calibre ONLY automatically extracts a KNOWN cover when it ADDS.books

Thanks, yes, that's what I meant. When adding books I drag them from the Windows explorer into the Calibre window.

[davidfor]

Originally Posted by lumpynose

So is it correct to say that the 3 likely scenarios are, 1) the book has no cover in the epub and calibre generates one from the initial text, 2) the book has a cover image, but it's not in an xhtml file that's tagged as the cover / title page, and 3) the book has a cover image and is in the cover /title page. With scenarios 2 and 3 calibre extracts the cover image and displays it when you're using its cover grid mode.

That's basically right. When you add the book, or press the set cover button in the metadata editor, calibre examines the book and tries to get a cover. There are a few methods which include "image with name cover". Or "image in first file". I don't know if there is a difference in the methods used when adding a book or pressing the set cover button.

Scenarios 1 and 2 are where the margins are messed up but the epub can be transformed into scenario 3 by running Polish books or Modify ePub.

Short of opening each epub in calibre's editor, is there an easy way to differentiate between an epub in scenarios 2 and 3? Or can I run Polish books on all of them and ignore whatever state they're in? (Probably not a bad idea in general, in order to smarten the punctuation and other stuff.)

Running Polish books or Modify ePub do not harm anything. My process is usually to update the metadata and cover when I add the book to my library. And then send it to the device. If the cover doesn't show up, I'll fix it. Otherwise, I'll probably leave it until I read the book. Then I fix whatever is needed. It does depend on other things. If I find a particular series/author/publisher/source have problems, I'll fix them before putting them on the device. For example, books from Smashwords are usually badly constructed. I usually fix these soon after adding them to my library.

In any case, even when I do fix things when adding, I am not adding enough books for it to be a pain.

[lumpynose]

Originally Posted by davidfor

That's basically right. When you add the book, or press the set cover button in the metadata editor, calibre examines the book and tries to get a cover. There are a few methods which include "image with name cover". Or "image in first file". I don't kn

Ok, thanks. (Do you remember what you typed that got cut off?)

(Irrelevant note: whenever I see Polish book I mentally pronounce it with the long o, like the language or nationality, e.g., Polish sausage.)

[davidfor]

Originally Posted by lumpynose

Ok, thanks. (Do you remember what you typed that got cut off?)

I remember thinking about how to finish that and got distracted. I've fixed the post, but the sentence is:

I don't know if there is a difference in the methods used when adding a book or pressing the set cover button.

(Irrelevant note: whenever I see Polish book I mentally pronounce it with the long o, like the language or nationality, e.g., Polish sausage.)

I did the same thing when it was first added to calibre. It is an interesting word, as without any other context, the pronunciation and meaning changes depending on the case of the first letter.

[lumpynose]

Ok, great; thanks!

[lumpynose]

Originally Posted by davidfor

Running Polish books or Modify ePub do not harm anything.

What's with the "Failed to find obfuscation key" error?

I ran Polish books on all of my books and this error came up with some books I'd bought from Amazon. Searching gave me the solution to do an EPUB -> EPUB conversion and then they transferred.

In the future should I avoid running Polish books on EPUBs that have been converted from Amazon purchases or does it not matter and I can jump through the extra hoops by doing the conversion?

Edit: I think I may be confused; I may not have previously uploaded these converted books with the Extended Driver. So maybe the error wasn't due to Polish books?