How to calculate sum of pixel values in grey scale images.

Hi all,

I have a grey scale image that contains a tumour uptake and i want to know how to calculate the sum of all pixel values (intensities) within this tumour. I have selected the ROI where i want to calculate the uptake value. I called this image myROI.

Can you help in this, please ?

Answer 1

[Guillaume]

Not many details are given, but shouldn't it be:

sum(myROI(:))  %sum of all values in array myROI

If on R2018b or later, you can also use:

sum(myROI, 'all')