image processing area calculation

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!

Answer 1

[Image Analyst]

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

Answer 2

[linson vincent]

how to find area of a image using matlab

[Image Analyst]

Multiply the number of pixels in the image by the spatial calibration factor in real world units per pixel. See attached spatial calibration demo.