The book itself took about 10 hours or so and was mostly just a collection of writings I already had and email responses.

I have spent more than 10 hours on a single online post multiple times.

I just checked it on Amazon, and there's not a whole lot of concrete information of what I will find in the book. I guess it is a niche indeed and people who are looking for it will know already. Maybe image algorithms?

If you had to take a picture of the most interesting / telling page of the book (to try to sell the rest of it) which page would it be? And do you mind doing it.

I actually get almost no sales through Amazon. Most come through either Leanpub followed by Gumroad.

http://www.boyter.org/decoding-captchas/

That's the link that generates 99% of sales. It gives you a fair idea of what is contained. Email me via my profile if you need more information.

That seems to be what I was asking for, thanks. Seems interesting.