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Chris Jones · 02-23-2016, 03:15 PM

Images in epubs do not seem to scale in order to take into account the specs of the e-reading device and as a result a given epub's images may appear reasonably sized on one device and much smaller on another.

One particular example where this is causing me a problem is the LaTeX Companion from Addison-Wesley Professional: there are many diagrams and code samples packaged as jpeg files that are legible in the Calibre ebook-viewer on my laptop but turn out to be totally undecipherable on higher resolution screens such as the Kobo Glo or the Nexus 7 Android tablet making the book useless on such devices.

I looked at a number of illustrated novels from the mobileread site and they all appear to do the same in this respect: on higher resolution devices (I'm guessing this is what is causing the problem...?) some of the images are about the size of a postage stamp to the point that with some of them you cannot even tell at a glance what they're supposed to represent...!

Isn't there a way to work around this issue and to make images the same size relative to the size of the screen on any device?

What I have in mind in a rather vague way is something like specifying that the image is to be displayed in a box/container that occupies a given percentage of the screen and scaled to fit into that box.

Not intrinsically different from the way book covers are handled and this appears to work on all kinds of devices.

Would anyone know how the designers of the epub standard recommend this should be addressed and where it is documented?

02-23-2016, 03:15 PM	#1
Chris Jones Addict Posts: 242 Karma: 37089 Join Date: Oct 2012 Device: none	Scaling images in illustrated epubs Images in epubs do not seem to scale in order to take into account the specs of the e-reading device and as a result a given epub's images may appear reasonably sized on one device and much smaller on another. One particular example where this is causing me a problem is the LaTeX Companion from Addison-Wesley Professional: there are many diagrams and code samples packaged as jpeg files that are legible in the Calibre ebook-viewer on my laptop but turn out to be totally undecipherable on higher resolution screens such as the Kobo Glo or the Nexus 7 Android tablet making the book useless on such devices. I looked at a number of illustrated novels from the mobileread site and they all appear to do the same in this respect: on higher resolution devices (I'm guessing this is what is causing the problem...?) some of the images are about the size of a postage stamp to the point that with some of them you cannot even tell at a glance what they're supposed to represent...! Isn't there a way to work around this issue and to make images the same size relative to the size of the screen on any device? What I have in mind in a rather vague way is something like specifying that the image is to be displayed in a box/container that occupies a given percentage of the screen and scaled to fit into that box. Not intrinsically different from the way book covers are handled and this appears to work on all kinds of devices. Would anyone know how the designers of the epub standard recommend this should be addressed and where it is documented?