def generateRidgedMulitFractal(fn, w, h, freq):
"""Generates an image file of ridged multifractal noise.
fn - File name for the image.
w - Width of the image, in pixels.
h - Height of the image, in pixels.
freq - The frequency of the noise.
numOctaves = The number of octaves of noise to use.
"""
noiseSource = PerlinNoise()
img = Image.new('RGB', (w,h))
pix = img.load()
for x, y in itertools.product(range(0,w), range(0,h)):
n = abs(noiseSource.getValue(float(x)/w/freq,
float(y)/h/freq,
0.0))
c = int(255 - n*255)
pix[x,y] = (c,c,c)
img.save(fn)
