Masked image displaying wrong intensity
4 visualizzazioni (ultimi 30 giorni)
Mostra commenti meno recenti
Fotaras Sitof
il 21 Set 2017
Commentato: Fotaras Sitof
il 21 Set 2017
Hey guys,
I have a 3D image: [256x256x160] and a mask: [256x256x160]. The mask is a binary image of 0 and 255. After applying the mask on the image:
if true
% masked_image = image.*mask;
end
I get a masked_image that has totally wrong intensity values. In fact, its values are nowhere to be found on the original image. They are just too big. All I want to achieve is extract the original image's intensities at the location of the mask and calculate the mean value of that ROI. I can see from 'imshow' that the mask is aligned properly on the image. However, applying the mask is unsuccessful and I don't understand why.
Many thanks for your help.
0 Commenti
Risposta accettata
OCDER
il 21 Set 2017
Modificato: OCDER
il 21 Set 2017
Try this instead, which will select only the pixels in image dictated by the mask:
%to get the masked image without changing the dimension of the image
masked_image = image.*(mask > 0);
%or if you want just the pixels
masked_image_pixels = image(mask > 0);
Note that mask should really be a logical array, not a uint8 array, which is what (mask > 0) is taking care of for you.
In your original code, the issue is that you are using a uint8 mask matrix to multiply element-by-element with the image matrix. This means doing the following:
image .* mask
(value from the image matrix) x (255 or 0 from the "binary" uint8 mask matrix)
which would explain the large numbers.
Più risposte (0)
Vedere anche
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!