Navigating EPUB CFIs – Part 2

Once more unto the breach, dear friends, once more… I promise only once more!

Okay, so I’m trying to steel myself up to write the second half of the CFI post I swore to myself I’d come back to after the first part. If I don’t get this done by year end, it may never see the light of day.

The assumption at this point is that you understand the basic referencing mechanism in play, as I’m only going to look this time at the mechanisms that exist having reached your destination. If you don’t have the foggiest what all the slashes and even and odd numbers mean, have another go at the first part.
Continue Reading Navigating EPUB CFIs – Part 2

Navigating EPUB CFIs – Part 1


It’s not a topic I grew up dreaming of writing about one day, but it seems like a useful topic to cover, since questions about how to read them come up from time to time (see this recent thread on CFIs in the IDPF forums). I squeezed a quick explanation of them into the Best Practices book, but I had to keep it short, so maybe I can do better justice to them here.

I will say that the specification can be much more daunting to read than CFIs actually are, but that’s not an indictment of the specification. It’s just that CFIs are one of the more technically complex features that were included in EPUB 3.

But let’s start at the beginning: what is a “CFI”?Continue Reading Navigating EPUB CFIs – Part 1