I found a larger image here: http://www.rhinopressbooks.com/all/kolkata-the-juergen-teller-purple-book-1
It's an unusual “O” – it appears similar that of Grund but none of the other characters match.
I'll let you know if I make any better progress identifying the typeface.
Here’s another look at purple.fr. I believe this is a custom typeface or a proprietary revival. There is no digital match. The question was asked on dafont back in March and no replies, and on Typophile way back in 2013 with guesses that it’s modified or completely custom.