image processing area calculation

3 views (last 30 days)
Maria Rodriguez
Maria Rodriguez on 18 Jul 2014
Commented: Image Analyst on 26 Jan 2018
Hi,
I am new to image processing in matlab and I am trying to get an area measurement out of histology slides. I want to convert the image to binary get a pixel count of the white area and using a known distance (scale bar) in the image calculate the area.
I am using a sample code for medical image processing webinar but I am having trouble getting the right amount of contrast in my images I am not getting them to completely convert to a binary image.
Is there a way for me to first close out the edges that are not complete in the image and fill and then convert to binary or another method that would work?
function [image] = getCA(image)
A = imread (image);
glayer = A(:,:,2);
figure;
imshow(glayer)
agray = rgb2gray (A);
level = graythresh (agray);
abinary = ~im2bw(glayer, level);
figure;
imshow(abinary)
cc = bwconncomp (abinary);
stats = regionprops (cc, 'basic');
B = [stats.Area];
[~,biggest] = max(B);
abinary(labelmatrix(cc)~=biggest) = 0;
imshow(abinary)
abinary = imfill(abinary, 'holes');
Thanks so much for the help!

Answers (2)

Image Analyst
Image Analyst on 18 Jul 2014
image is the name of a built in function. Do not use it as the name of a variable.
I'm not sure what you're calling "white" in the image, and what region(s) you'd like the area of.
I don't see any code there where you are trying to extract the 300 um scale bar.
See my Image Segmentation Tutorial for how to threshold and get areas: http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862

linson vincent
linson vincent on 26 Jan 2018
how to find area of a image using matlab
  1 Comment
Image Analyst
Image Analyst on 26 Jan 2018
Multiply the number of pixels in the image by the spatial calibration factor in real world units per pixel. See attached spatial calibration demo.

Sign in to comment.

Categories

Find more on Biomedical Imaging in Help Center and File Exchange

Community Treasure Hunt

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

Start Hunting!