import PythonMagick
img = PythonMagick.Image('a.pdf') # use your full path here
img.write('original.jpg')
imgLowRes = PythonMagick.Image(img) # make a copy
imgLowRes.resize('220x')
imgLowRes.write('lowRes.jpg')
img.resize('48x')
img.write('thumb.jpg')