- p = popen(["compare", '-alpha', 'opaque', '-metric', 'AE', '-fuzz', '5%', ref_image, image, delta_image])
+ p = popen([
+ 'compare',
+ '-alpha', 'opaque',
+ '-metric', 'AE',
+ '-fuzz', '5%',
+ '-dissimilarity-threshold', '1',
+ ref_image, image, delta_image
+ ], stderr = subprocess.PIPE)