Search code examples
pythonimageopencvimage-processingroi

Region of Interest opencv python

I am trying to get a region of an image (ROI) using opencv python. The version of opencv used is 2.4.3. However when I try to call the API

cv2.SetImageROI

it returns this error

AttributeError: 'module' object has no attribute 'SetImageROI'

Also on checking the documentation it seems to suggest this api is a legacy python function. http://docs.opencv.org/2.4.3/search.html?q=setimageroi

I am not sure how to go about getting the ROI using this current version of opencv in python. Could some one please suggest how to go about this?

Thanks

Solution

  • Okay, On further analysis realized that the cv2 since it has been supporting numpy array structure, there is no longer any need for a API, the entire image can be manipulated in the array itself. eg:

    img = cv2.imread('image.png')
img = img[c1:c1+25,r1:r1+25]

    Here c1 is the left side column pixel location, and r1 is the corresponding row location. And img now has the image specified within the pixels as the ROI.

    EDIT: Very nicely explained here, How to copy a image region using opencv in python?