Python:只想在 OpenCV 中显示红色通道

Question

我是图像处理的初学者。我在许多色彩空间中显示图像，下面的代码在 3 通道 R G B 中显示图像，但图像以灰色布局显示。我需要显示三张图像，一张红色通道为红色图像，另一张为蓝色，最后一张为绿色。提前谢谢。

# cspace.py
import cv2
import numpy as np
image = cv2.imread('download.jpg')
# Convert BGR to HSV
hsv = cv2.cvtColor(image, cv2.COLOR_BGR2HSV)
hsl = cv2.cvtColor(image, cv2.COLOR_BGR2HLS) # equal to HSL
luv = cv2.cvtColor(image, cv2.COLOR_BGR2LUV)

#RGB - Blue
cv2.imshow('B-RGB.jpg',image[:, :, 0])
cv2.imwrite('B-RGB.jpg',image[:, :, 0])
# RGB - Green
cv2.imshow('G-RGB',image[:, :, 1])
cv2.imwrite('G-RGB.jpg',image[:, :, 1])
# RGB Red
cv2.imshow('R-RGB',image[:, :, 2])
cv2.imwrite('R-RGB.jpg',image[:, :, 2])

cv2.waitKey(0)

当前显示的蓝色图像

我需要像这张图片一样显示蓝色通道

Answer 1

您可以只复制原始图像并将一些通道设置为 0。

import cv2
image = cv2.imread('download.jpg')
b = image.copy()
# set green and red channels to 0
b[:, :, 1] = 0
b[:, :, 2] = 0

g = image.copy()
# set blue and red channels to 0
g[:, :, 0] = 0
g[:, :, 2] = 0
r = image.copy()
# set blue and green channels to 0
r[:, :, 0] = 0
r[:, :, 1] = 0

# RGB - Blue
cv2.imshow('B-RGB', b)
# RGB - Green
cv2.imshow('G-RGB', g)
# RGB - Red
cv2.imshow('R-RGB', r)
cv2.waitKey(0)

Answer 2

import cv2
import numpy as np
channel_initials = list('BGR')
image = cv2.imread('download.jpg')
for channel_index in range(3):
    channel = np.zeros(shape=image.shape, dtype=np.uint8)
    channel[:,:,channel_index] = image[:,:,channel_index]
    cv2.imshow(f'{channel_initials[channel_index]}-RGB', channel)
cv2.waitKey(0)