python中cv2.imread()和Image.open()的区别和联系详解

import cv2

img = cv2.imread("img_path")
print(img.shape, type(img))

# 显示图像
cv2.imshow("demo", img)

# 窗口显示时间，默认0表示无限
cv2.waitKey()

# 按任意键销毁窗口
cv2.destoryWindows("demo")

>>>输出
（345,678,3） <class.'numpy.ndarray'>

import cv2

# 方法1：BGR 转 RGB
img = img[:, :, ::-1]

# 方法2：BGR 转 RGB
img = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)

import cv2
imgFile = './images/测试.jpg'
# cv2.imread(imgFile)  读取失败但不会报错
img = cv2.imdecode(np.fromfile(imgFile, dtype=np.uint8), -1)

from PIL import Image

img = Image.open('./image9.jpg')
print(img, img.size)
img.show()

>>>输出
<PIL.JpegImagePlugin.JpegImageFile image mode=RGB size=1920x1080 at 0x222AD1D4160> (1920, 1080)

import cv2
from PIL import Image

img_cv2 = cv2.imread('img_path')

# 方法1
img_cv2 = img_cv2[:, :, ::-1]

# 方法2 
img_cv2 = cv2.cvtColor(img_cv2, cv2.COLOR_BGR2RGB)

img_PIL = Image.fromarray(img_cv2)

import cv2
from PIL import Image
import numpy as np

img_PIL = Image.open('img_path')

img_cv2 = np.array(img_PIL)

# 方法1
img_cv2 = img_cv2[:, :, ::-1]

# 方法2
img_cv2 = cv2.cvtColor(img_cv2, cv2.COLOR_RGB2BGR)