手绘图片

原图

from PIL import Image
import numpy as np
vec_e1=np.pi/2.2
vec_az=np.pi/4.
depth=10.
im=Image.open('C:\\Users\\GPC2019\\Desktop\\01.jpg').convert('L')
a=np.asarray(im).astype('float')
grad=np.gradient(a)
grad_x,grad_y=grad
grad_x=grad_x*depth/80.
grad_y=grad_y*depth/80.
dx=np.cos(vec_e1)*np.cos(vec_az) #光源对图像x轴的影响
dy=np.cos(vec_e1)*np.sin(vec_az)
dz=np.sin(vec_e1)
A=np.sqrt(grad_x**2+grad_y**2+1.)
uni_x=grad_x/A
uni_y=grad_y/A
uni_z=1./A
a2=255*(dx*uni_x+dy*uni_y+dz*uni_z)
a2=a2.clip(0,255)
im2=Image.fromarray(a2.astype('uint8'))
im2.save('C:\\Users\\GPC2019\\Desktop\\01.jpg')