How do I resize a binary image?

27 views (last 30 days)
Tola on 10 May 2013
Answered: Josep Llobet on 6 Aug 2021
I tried using imresize but it is not showing the image I sent in. The white pixels are no longer there and I just have a blank black background. Thank you.

Accepted Answer

Walter Roberson
Walter Roberson on 10 May 2013
imresize(double(OriginalImage), .....)
It might be meaningful to convert back to binary afterwards.
Tola on 11 May 2013
The original image is actually a binary image just that performing imresize directly on it removed the white pixels on it and gave a blank black image. But when it was converted to double and imresize done on it, it gave out the correct image in double so I just converted it back to binary. Thank you for your help.

Sign in to comment.

More Answers (1)

Josep Llobet
Josep Llobet on 6 Aug 2021
Hi there,
Values in the resized image change to non-binary. Then, you can simply turn to binarize the image for filter the values and turn to have a binary image:
I_BW = imread("hands1-mask.png");
%class(I_BW) % <- to see the type of image
I_BW_resize = imresize(double(I_BW), 2);
%unique(I_BW_resize) % <- to see the diferent values (-0.1659, -0.1564, -0.1516...)
I_BW_resize = imbinarize(I_BW_resize);
imshowpair(I_BW, I_BW_resize, "montage");
%unique(I_BW_resize) % <- to see the diferent values (1, 0)
With the MATLAB app Image Viewer. Using the button you can see the pixel values. For call the app you can do as the example:

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by