Python使用PIL库将彩色图像转换为灰度图的完整代码示例

from PIL import Image
import os
 
# 图像组成：红绿蓝 （RGB）三原色组成 亮度（255,255,255）
image = "Annie1.jpg"
img = Image.open(image)
img_all = "素描" + image
new = Image.new("L", img.size, 255)
width, height = img.size
img = img.convert("L")
# print(img.size)
# print(img.mode) #RBG
#
# img_get = img.getpixel((0, 0))
# print(img_get) #三原色通道
#
# img_L=img.convert('L')
# print(img_L)
# img_get_L=img_L.getpixel((0,0)) #换算 得到灰度值
# print(img_get_L)
 
# 定义画笔的大小
Pen_size = 3
# 色差扩散器
Color_Diff = 6
for i in range(Pen_size + 1, width - Pen_size - 1):
 for j in range(Pen_size + 1, height - Pen_size - 1):
  # 原始的颜色
  originalColor = 255
  lcolor = sum([img.getpixel((i - r, j)) for r in range(Pen_size)]) // Pen_size
  rcolor = sum([img.getpixel((i + r, j)) for r in range(Pen_size)]) // Pen_size
 
  # 通道----颜料
  if abs(lcolor - rcolor) > Color_Diff:
   originalColor -= (255 - img.getpixel((i, j))) // 4
   new.putpixel((i, j), originalColor)
 
  ucolor = sum([img.getpixel((i, j - r)) for r in range(Pen_size)]) // Pen_size
  dcolor = sum([img.getpixel((i, j + r)) for r in range(Pen_size)]) // Pen_size
 
  # 通道----颜料
  if abs(ucolor - dcolor) > Color_Diff:
   originalColor -= (255 - img.getpixel((i, j))) // 4
   new.putpixel((i, j), originalColor)
 
  acolor = sum([img.getpixel((i - r, j - r)) for r in range(Pen_size)]) // Pen_size
  bcolor = sum([img.getpixel((i + r, j + r)) for r in range(Pen_size)]) // Pen_size
 
  # 通道----颜料
  if abs(acolor - bcolor) > Color_Diff:
   originalColor -= (255 - img.getpixel((i, j))) // 4
   new.putpixel((i, j), originalColor)
 
  qcolor = sum([img.getpixel((i + r, j - r)) for r in range(Pen_size)]) // Pen_size
  wcolor = sum([img.getpixel((i - r, j + r)) for r in range(Pen_size)]) // Pen_size
 
  # 通道----颜料
  if abs(qcolor - wcolor) > Color_Diff:
   originalColor -= (255 - img.getpixel((i, j))) // 4
   new.putpixel((i, j), originalColor)
 
new.save(img_all)
 
i = os.system('mshta vbscript createobject("sapi.spvoice").speak("%s")(window.close)' % '您的图片转换好了')
os.system(img_all)