如何使用python在openCV中将一系列HSV值的所有像素设置为另一个值？

Question

i am using OpenCV with python. i want to replace the range of color by " white " color.

color range:

HMin = 130
SMin = 65
VMin = 135
HMax = 200
SMax = 160
VMax = 255

i know how to replace specific pixel value to another value:

im[np.where((im == [20,78,90]).all(axis = 2))] = [0,0,100]
cv2.imwrite('output.png', im)

so, do you know how could i use this method to set all pixels of a range of HSV values instead of a specific pixel value to another value?

Answer 1

Use inRange to find the mask, then replace the origin image with other value.

The following is replace the GREEN range into RED.

import numpy as np
import cv2

img = cv2.imread( "sunflower.jpg" )

## convert to hsv
hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)

## mask of green (36,0,0) ~ (70, 255,255)
mask = cv2.inRange(hsv, (36, 0, 0), (70, 255,255))
bak = img.copy()

# replace with red 
bak[mask > 0] = (0, 0, 255)

cv2.imwrite("bak.png", bak)

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Some links:

1. How to define a threshold value to detect only green colour objects in an image :Opencv

2. How to change the image color when the pixels hsv values are in specific ranges?