I have segmented a image using region growing. Now i want to count number of pixels in each regions. How can i do that?

I have segmented a image using region growing. Now i want to count number of pixels in each regions. How can i do that? i want all the regions which have less than 100 pixels.

Answer 1

[Image Analyst]

% Extract only small blobs:
bigBlobs = bwareaopen(binaryImage, 100);
smallBlobs = binaryImage - bigBlobs;

% Measure areas
labeledImage = bwlabel(smallBlobs);
measurements = regionprops(labeledImage, 'Area');
allAreas = [measurements.Area]

[Macarena Santillan]

Where is the part that counts the pixels? I hace a similar issue. I am trying to find the amount of pixels enclosed in a region of my image. But I am not sure in which part of the code you jus typed are you extracting that number. Why are you measuring areas?

[Image Analyst]

The regionprops() function is the part that counts all the pixels in each region.

allAreas is a vector that counts the number of pixels in each region. For example if your mask had two regions with 12000 and 25000 pixels, then allAreas would be [12000, 25000]

I am measuring areas because area has units of pixels and the area is the count of the number of pixels in the region.