python生成圆形图片的方法

# -*- coding: utf-8 -*- """ __author__= 'Du' __creation_time__= '2018/1/5 9:08' """  import os, math from PIL import Image   def circle():  ima = Image.open("ball1.jpg").convert("RGBA")  # ima = ima.resize((600, 600), Image.ANTIALIAS)  size = ima.size  print(size)   # 因为是要圆形，所以需要正方形的图片  r2 = min(size[0], size[1])  if size[0] != size[1]:   ima = ima.resize((r2, r2), Image.ANTIALIAS)   # 最后生成圆的半径  r3 = 60  imb = Image.new('RGBA', (r3*2, r3*2),(255,255,255,0))  pima = ima.load() # 像素的访问对象  pimb = imb.load()  r = float(r2/2) #圆心横坐标   for i in range(r2):   for j in range(r2):    lx = abs(i-r) #到圆心距离的横坐标    ly = abs(j-r)#到圆心距离的纵坐标    l = (pow(lx,2) + pow(ly,2))** 0.5 # 三角函数 半径     if l < r3:     pimb[i-(r-r3),j-(r-r3)] = pima[i,j]  imb.save("test_circle.png")  circle()