Try nxivm
I'm looking through the source code trying to see if one could modify it slightly so that you can run a dictionary against a picture.
Anon is right though. If we simply doing stuff simply for the sake of doing it we will just spin our wheels.
There has to be clues about where to look or else without some type of automation like a brute force attack we're not going to get close to all of the possible combinations.
Anons, I think Q is talking to the Black Hats again.
"Hey we know you're sending messages via images."
If he was pointing to us to do something he would have most likely given us more to go on.
Also, that's assuming they even used pixelknot. They could have used a program that uses a different stenography algorithm.
You're going to shit up the bread.
If I were a Black Hat I'd throw a bunch of passwords at you that were never tried. We're anon remember.