Need comic epub for learning

[icearch]

I need some comic epub files to looking into it's internal structure, to see what's different from text based epub.

Can someone share some all image comic epub flies? Or tell me which title should I looking for.

[KevinH]

Please note epub3 books made of only of images means that images are used in the spine and that is not well supported for many e-reader platforms and there is still debate on how and if they should be allowed. There is also the question of accessibility i.e. where should the alt image description be put for screen reading and accessibility software.

All of this points to using only xhtml files in the spine each loading its own image (either directly or via an svg wrapper) which includes alt info or svg description as required for accessibility as well as other additional information to allow for screen reading of any text or translations.

Most current comic books are in a specialized non-epub format as the epub3 spec has not really been clear.

Even Sigil requires each page to be an xhtml file in the OPF spine to be as conservative as possible and allow their use on any e-reader. These xhtml pages can of course contain a single image or inline svg. That is why most true comic books use their own unique format, not epub.

[JSWolf]

If you want accessibility for comics, you would need to put in all the text and make it not displayed so reading systems can handle reading it to you. Also, you can't put text in alt that would work as you'd have to describe every single frame in that one alt.

Comics and accessibility in ePub do not go together.

[KevinH]

Or simply use a fixed layout for both and make each subframe a separate image with its own alt. I have seen that.

[icearch]

I see, how to use svg in xhtml files? I have only used img tag to link pic files.

And another thing, I see pictures in full screen ( in reader of course), but I have no idea how they do it. The img tag only put pics in texts, even with only one pic per xhtml file, the pic still sits on normal page background, not a full screen like gallery mode.

[Turtle91]

Originally Posted by icearch

I see, how to use svg in xhtml files? I have only used img tag to link pic files.

And another thing, I see pictures in full screen ( in reader of course), but I have no idea how they do it. The img tag only put pics in texts, even with only one pic per xhtml file, the pic still sits on normal page background, not a full screen like gallery mode.

SVG wrapper will do all the heavy lifting for taking up a full screen (-ish)...but you still have the issues of accessibility...almost requiring a single frame image per xhtml page.

[icearch]

I do not understand, what is a svg wrapper? Googleing it gives a lot of different results. Do I code the wrapper my self? Do I download some software? Do I copy someone's code?

[Gormagon]

Since comics are images I really don't see any use for the epub format instead of the archives cbz or cbr, which are just zip or rar archives with images. But then I only use android based devices for mobile reading. Although SumatraPDF can display cbr and cbz files on windows as well.

[Turtle91]

An SVG wrapper is just a way to use some of the built-in functionality of an SVG and apply it to a non-SVG image. Something like this:

<svg xmlns="http://www.w3.org/2000/svg" version="1.1" 
     xmlns:xlink="http://www.w3.org/1999/xlink"
     preserveAspectRatio="xMidYMid meet"
     height="100%" width="100%"
     viewBox="0 0 512 512">
     <image width="512" height="512" xlink:href="../Images/img_faq.png"/>
</svg>

The key functionality is the preserveAspectRatio="xMidYMid meet" which allows the image to be centered and fill the entire screen while maintaining the correct aspect ratio. The image size is defined (height, width)

There are other, more advanced uses, that allow you to add captions and limit the image size so it doesn't take up the full screen.

In Sigil you can set up a template file that will do most of the work for you when you use the "Add Cover" tool. You can find the exact instructions in the User Guide. I made a template like this for ePub2 (you can make another one for ePub3):

<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
  <title>enter-title</title>
  <style type="text/css">
    *   {padding:0; margin:0; background-color:black}
    h1  {display:none}
    div {width:97vw; height:97vh ; margin:1.3vh auto}
  </style>
</head>

<body>
  <h1 title="Cover"/>
  <div>
    <svg xmlns="http://www.w3.org/2000/svg" version="1.1" 
         xmlns:xlink="http://www.w3.org/1999/xlink"
         preserveAspectRatio="xMidYMid meet"
         height="100%" width="100%"
         viewBox="0 0 SGC_IMAGE_WIDTH SGC_IMAGE_HEIGHT">
         <image width="SGC_IMAGE_WIDTH" height="SGC_IMAGE_HEIGHT" xlink:href="SGC_IMAGE_FILENAME"/>
    </svg>
  </div>
</body>
</html>

I use the surrounding <div> and the leading <h1> to help with styling and ToC generation.

This works great for a cover page, but if you want to make additional pages then you can either copy/paste the appropriate section, or you could use one of the plugins from the Sigil Plugin Index called InsertImageSVG to help.

[DNSB]

I've been using code rather similar to Turtle91's for doing kids books that use full page images. For me, the header allows creating a ToC without requiring me to manually create one every time I make a change. With a few changes, you can use the same wrapper for ePub2 and ePub3.

[icearch]

I see, I will look into it.

Another thing:

  <svg xmlns="http://www.w3.org/2000/svg" version="1.1"

Would it actually connect to www.w3.org to get detailed info or the file/reader would cover this? That is, does it need internet connection to function?

[icearch]

After some experiment, I found it depends on the reader.

So I think I will just copy cover code to make every img in separate xhtml files.

[KevinH]

Originally Posted by icearch

I see, I will look into it.

Another thing:

  <svg xmlns="http://www.w3.org/2000/svg" version="1.1"

Would it actually connect to www.w3.org to get detailed info or the file/reader would cover this? That is, does it need internet connection to function?

No, it will not need an internet connection to function. That is an xml namespace identifier attribute. That url/uri is used as an unique identifier of the namespaces for the svg tags. It is just a guaranteed unique string. An actual website specified in that url/uri need not exist.

Under old pure xml if you were using a fully validating parser and specified the location of a schema, a schema might be downloaded that defined these new tags but svg has long been integrated into normal html and xhtml with modern parsers.

[icearch]

I see, thank you.

[Jellby]

I learned from calibre's changelog that there's something called "'Open Manga Format' non-conformant EPUB files produced by some Japanese publishers". Maybe that's what you're looking for?