How can i change specific pixels value in a binary image?

Hello everyone, i got this image from a segmentation of the left atrium and i want to get rid of the portion of the pulmonary veins. So how can i set pixels to zero above the red line to get the atrium?

Answer 1

[Image Analyst]

Try drawpoints or imfreehand(). See attached masking demos.

[Matteo Rossi]

Thanks a lot it works. Would there also be a way to eliminate those portions automatically? For example taking advantage of the general information of the image. I came up with the idea of calculating the curvature and applying morphological operators up to the maximum curvature but I was unable to implement it as a code.

[Image Analyst]

I don't know. I tried thresholding the Euclidean distance transform (attached) but it was not great. I think for this you might try deep learning.

[Matteo Rossi]

You're absolutely right, unfortunately the task is to segment several slices with a Chan-Vese and then reconstruct the volume of the atrial chamber with a mesh, but I must first eliminate the pulmonary veins. Thanks anyway.

[Image Analyst]

You can find lots of algorithms on medical image processing here: http://www.visionbib.com/bibliography/contents.html

See section 20 on medical applications.