#!/usr/bin/ruby -w
require 'digest/md5'

filename = 'myimage.png'

# Generate a hash from the file contents
digest = Digest::MD5.hexdigest(File.read(filename))

# Mersenne Twister RNG with seed
prng = Random.new(digest)

# Generate numbers
strength = prng.integer(20)
agility = prng.integer(20)