Amazon eInk Devices: Hidden Text Possible?

[tobias.wantzen]

Hello,

there are images with text on them, which should be searchable, in my actual eBook. So I decided to embed the image, set all the image text as HTML text down under it, and hide that text with CSS:

p.hidden {
	color: #fff;
	visibility: hidden;
	font-size: 1px;
	line-height: 1px;
}

Within EPUB and all KF8 devices everything is fine. But the eInk doesn't work.

Is there any option to make this work? Or: Is there any better workaround, that is good enough for all devices?

Thanks
Tobias

[GrannyGrump]

have you tried adding

display: none



Then you should not have to worry about setting font sizes and color and line height.

(it is better never to set color anywhere, to prevent conflict with the user's choice of colors.
I understand also, that Kindle devices will not honor line-height below 120%. I could be wrong about that though, you should check the Amazon current formatting guidelines)

[DiapDealer]

Originally Posted by tobias.wantzen

Within EPUB and all KF8 devices everything is fine. But the eInk doesn't work.

There's plenty of eInk devices that support KF8. Perhaps you meant it doesn't work in the old mobi-format?

[tobias.wantzen]

Yes, I meant the old MOBI. Kindle Previewer 3.9 displays everything fine. Kindle Previewer 2.94, Kindle DX shows the problems.

I tried display: none; and Kindle DX (Previewer 2.94) hides the text. What I couldn't test is the searchability, because it is not working correctly in my Previewer installations. I chose visibility: hidden; over display: none; because of searchability.

Tobias

[tobias.wantzen]

BTW: Thanks for your suggestions!

[DiapDealer]

I don't think "display: none", or "visibility: hidden" are supported in the mobi format. In fact, css isn't supported in the mobi format at all. Now that's not to say that the kindlegen conversion process can't massage certain css input into mobi-compliant markup, but I know of no mobi markup (which is essentially HTML 3.2) that will create hidden text that's still searchable. In all likelihood, "display: none" (as well as "visibilty: hidden") will simply cause the text to be left out of the mobi markup entirely after conversion. In short: I strongly suspect that invisible text that can still be searched is simply not possible in the older mobi-only format. But I could be wrong. Is an img tag's alt text searchable in mobi?

[Doitsu]

Originally Posted by DiapDealer

Is an img tag's alt text searchable in mobi?

Based on my informal tests, img tag alt text is not searchable in EPUB and MOBI7/AZW3 (tested with ADE 1.7-4.5, Mobipocket Reader, the Kindle for PC app and my PW2.)
I don't think that there's any mainstream epub/mobi app out there that actually supports img tag alt attributes. (Alt attribute values might be read by DAISY compliant apps with TTS support.)

[jhowell]

Most Kindle books are delivered by Amazon in KFX format these days. Based on my testing with Kindle Previewer 3, in conversion to KFX hidden text and image alt text is discarded and so will be unavailable for searching or TTS.


Edit: I was wrong. I retested and found that the alt text for images is actually preserved in KFX. I do not know if it is actually used for anything.

[tastyeng]

Originally Posted by jhowell

Edit: I was wrong. I retested and found that the alt text for images is actually preserved in KFX. I do not know if it is actually used for anything.

Kindle for PC with NVDA supports reading alt text. Not sure if any other Kindle platforms do.