Python图片转素描
from PIL import Image
import numpy as np
a = np.asarray(Image.open('ha.png').convert('L')).astype('float')
depth = 10. # (0-100)
grad = np.gradient(a) # 取图像灰度的梯度值
grad_x, grad_y = grad # 分别取横纵图像梯度值
grad_x = grad_x * depth / 100.
grad_y = grad_y * depth / 100.
A = np.sqrt(grad_x ** 2 + grad_y ** 2 + 1.)
uni_x = grad_x / A
uni_y = grad_y / A
uni_z = 1. / A
vec_el = np.pi / 2.2 # 光源的俯视角度,弧度值
vec_az = np.pi / 4. # 光源的方位角度,弧度值
dx = np.cos(vec_el) * np.cos(vec_az) # 光源对x 轴的影响
dy = np.cos(vec_el) * np.sin(vec_az) # 光源对y 轴的影响
dz = np.sin(vec_el) # 光源对z 轴的影响
b = 255 * (dx * uni_x + dy * uni_y + dz * uni_z) # 光源归一化
b = b.clip(0, 255)
im = Image.fromarray(b.astype('uint8')) # 重构图像
im.save('haHD.jpg')