How to convert numpy matrix to cv2 image [python]

python opencv numpy cv2
user2266175 picture user2266175 · Oct 14, 2017 · Viewed 29.6k times · Source

I have a numpy 2d matrix which represents a colored image. This matrix has some negative and floating point numbers but of course I can display the image using imshow(my_matrix).

my_matrix_screenshot

I need to perform histogram equalization to this colored image so I found a code here in stackoverflow using cv2 (OpenCV Python equalizeHist colored image) but the problem is I am unable to convert the 2d matrix to cv matrix which takes three channels for RGB.

I was searching again but all I found is to convert regular 3d numpy matrix to cv2 matrix so how can numpy 2d matrix be converted to cv2 matrix which has 3 channels?

Answer

shouhuxianjian picture shouhuxianjian · Feb 13, 2018

because the numpy.ndarray is the base of cv2, so you just write the code as usual,like

img_np = np.ones([100,100])
img_cv = cv2.resize(img_np,(200,200))

you can try

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