How to plot a 2D histogram of pixel pairs ?
3 views (last 30 days)
Show older comments
I have a 'M by 2' matrix consisting of pixel pairs in an image. I want to find which pixel pairs occur more frequently. For this I need to plot a 2D histogram. Any suggestions ?
0 Comments
Answers (2)
Azzi Abdelmalek
on 30 Mar 2014
If you can find the frequency of each pair, then you can find the most frequent one.
A=[1 2;3 4;1 2;5 6;1 2;5 6]
[ii,jj,kk]=unique(A,'rows')
f=histc(kk,1:numel(jj))
[a,idx]=max(f)
out=[ii(idx,:) a]
0 Comments
Image Analyst
on 30 Mar 2014
There is a special function made to exactly that. It's called graycomatrix() and is in the Image Processing Toolbox. It calculates what is called the Gray Level Cooccurrence Matrix. The GLCM is what you called the 2D histogram. My demo script is attached below in blue text. I show the GLCM as a 2D image, like a heat map.
0 Comments
See Also
Categories
Find more on Histograms in Help Center and File Exchange
Products
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!