详解python如何通过numpy数组处理图像

from PIL import Image
import numpy as np

# 读取图像，并转化为数组
im = np.array(Image.open("cat.jpg"))

# 灰度处理公式
gray_narry = np.array([0.299, 0.587, 0.114])
x = np.dot(im, gray_narry)

# 数组转图片
gray_cat = Image.fromarray(x.astype('uint8'))
# 保存图片
gray_cat.save('gray_cat.jpg')
# 展示查看
gray_cat.show()

from PIL import Image
import numpy as np

# 读取图像，并转化为数组
im = np.array(Image.open("cat.jpg"))
# 旋转
x = im[::-1]

# 数组转图片
cat2 = Image.fromarray(x.astype('uint8'))
# 保存图片
cat2.save('cat2.jpg')
# 展示查看
cat2.show()

import numpy as np
import matplotlib.pyplot as plt
n1 = plt.imread("cat.jpg")  # 读取了图片，转化为数组，三维的
plt.imshow(n1)
n2 = np.array([0.299, 0.587, 0.114])
x = np.dot(n1, n2)
plt.imshow(x, cmap="gray")
plt.show()