python中读取和查看图片的6种方法

file_name1='test_imgs/spect/1.png' # 这是彩色图片
file_name2='test_imgs/mri/1.png' # 这是灰度图片

1 OpenCV

注：用cv2读取图片默认通道顺序是B、G、R，而不是通常的RGB顺序，所以读进去的彩色图直接显示会出现变色情况，详情可以看：https://blog.csdn.net/weixin_45954454/article/details/114707888

import cv2
spect= cv2.imread(file_name1) # BGR
spect= spect[:, :, ::-1] # RGB
mri= cv2.imread(file_name2) # 灰度图
print(spect.shape) # (256, 256, 3)
print(mri.shape) # (256, 256, 3)   cv2读进来是三通道的图片

import matplotlib.pyplot as plt
plt.imshow(spect)
plt.show()

import matplotlib.pyplot as plt
fig=plt.figure()
f1 = fig.add_subplot(121)
f2 = fig.add_subplot(122)
f1.imshow(spect)
f2.imshow(mri)
plt.show()

2 imageio

import imageio 
spect = imageio.imread(file_name1) 
mri = imageio.imread(file_name2) 
print(spect.shape) # (256, 256, 3)
print(mri.shape) # (256, 256)

import matplotlib.pyplot as plt
fig=plt.figure()
f1 = fig.add_subplot(121)
f2 = fig.add_subplot(122)
f1.imshow(spect)
f2.imshow(mri,cmap='gray') # 注：单通道灰度图必须加上cmap='gray'才能正确显示
plt.show()

3 PIL

from PIL import Image
import numpy as np
spect= Image.open(file_name1) #  
spect.show()

4 scipy.misc

from scipy.misc import imread
spect = imread(file_name1)
mri = imread(file_name2)

import matplotlib.pyplot as plt
fig=plt.figure()
f1 = fig.add_subplot(121)
f2 = fig.add_subplot(122)
f1.imshow(spect)
f2.imshow(mri,cmap='gray') # 注：单通道灰度图必须加上cmap='gray'才能正确显示
plt.show()

5 tensorflow

from tensorflow.python.keras.preprocessing.image import load_img
spect = load_img(file_name1) #  

spect.show()

6 skimage

from skimage import io
import matplotlib.pyplot as plt
mri = io.imread(file_name2)#读取数据
plt.imshow(mri,cmap='gray') # 注：单通道灰度图必须加上cmap='gray'才能正确显示
plt.show()