processing.py 文件源码

def transform(image): #translate, shear, stretch, flips?
    rows,cols = image.shape

    angle = random.uniform(-1.5,1.5)
    center = (rows / 2 - 0.5+random.uniform(-50,50), cols / 2 - 0.5+random.uniform(-50,50))
    def_image = tf.rotate(image, angle = angle, center = center,clip = True, preserve_range = True,order = 5)

    alpha = random.uniform(0,5)
    sigma = random.exponential(scale = 5)+2+alpha**2
    def_image = elastic_transform(def_image, alpha, sigma)

    def_image = def_image[10:-10,10:-10]

    return def_image

# sigma: variance of filter, fixes homogeneity of transformation 
#    (close to zero : random, big: translation)