获取像素方法：
from PIL import Image
img = Image.open("xxx.jpg")
#将图片分成小像素方块
pix = img.load()
# 获取图片大小
width = img.size[0]
height = img.size[1]
#width,height = img.size
for x in range(width):
for y in range(height):
r, g, b = pix[x, y]
print(r, g, b)
修改像素方法：
from PIL import Image
img = Image.open("xxx.jpg")
#将图片分成小像素方块
pix = img.load()
# 获取图片大小
width = img.size[0]
height = img.size[1]
for x in range(0,width):
for y in range(0,height):
rgb = pix[x,y] # 获取一个像素块的rgb
r, g, b = pix[x, y]
if b>130 and r<120: # 自定义某些规则
pix[x, y] = (255, 0, 0) # 修改单个像素点
#============3.保存图片============
img.save("new.jpg")
