MATLAB: Take the average from a region of a plot and subtract the background

Image Processing Toolbox

I have a histogram ranging from 0 to 700 (along X axis). It is an exponential decay curve. I want to take the average from 600 to 700. This average is the background. I want to subtract this background from the plot. How can I perform this in Matlab?

Best Answer

Try this:

binaryImage = grayImage > 600;
meanGL = mean(grayImage(binaryImage ))
newImage = double(grayImage) - meanGL; % Casting to double is needed to get negative values.
imshow(newImage, []); % The [] is needed.

Related Solutions

MATLAB: I have an original image that has not been converted to binary. I have found the centroid for multiple areas, now I want to use them crop 288 pixel areas around centroid. I then want to calculate total summed pixel area. Can I use a for loop

Well, yeah. Did you check the size of xCentroids? It's a 1-D row vector, so size1 is 1 and thus your for loop executes only once. Then, your loop is basically not saving any sums at all. You'd have to add this line

theSums(k) = sum(double(pixellevel));

And you don't need to do

xCentroids(1,k);

you can just do

xCentroids(k);

No rows index of 1 is needed because there is only one row.

MATLAB: To Run a program for multiple times for different data and report result for each run

n = 10; % let number of your .asc files
outdata = cell(n,2);
t=0:1:1000;
figure;
for jj = 1:n
    nme = sprintf('VMIVolt%d.asc',jj);
    A = textread(nme);
    h=hist(A(:,1)./1000,t);
    meanBinIndex = sum(t(620:720) .* h(620:720)) / sum(h(620:720));
    BckgndCrctd_h=h-meanBinIndex;
    subplot(n,1,jj);
    plot(t,h,'*b',t,BckgndCrctd_h,'*r');
    outdata(jj,:) = {h,BckgndCrctd_h};
end

Best Answer

Related Solutions

MATLAB: I have an original image that has not been converted to binary. I have found the centroid for multiple areas, now I want to use them crop 288 pixel areas around centroid. I then want to calculate total summed pixel area. Can I use a for loop

MATLAB: To Run a program for multiple times for different data and report result for each run

Related Question