PIL添加一份像素序列到图像

直接上源码：

from PIL import Image

img = Image.open("图片路径")
img = img.convert("L")  #灰度化
img.show()

imgdata = list(img.getdata())
print(imgdata)

addlist = []
for i in range(len(imgdata)):
    if imgdata[i]>250:
        addlist.append(imgdata[i]-100)
    else:
        addlist.append(imgdata[i])
    
img.putdata(addlist)
img.show()