Steve on Image Processing

Watershed transform question from tech support 3

Posted by Steve Eddins,

Watershed transform question from tech support  A support call came in this week from a customer trying to use watershed to segment this image: The complaint was that calling watershed did not produce a good segmentation.Today I want to show how to use watershed to segment this image. Along the way I'll explain the difference between... read more >>

Chess and a little text file manipulation 1

Posted by Steve Eddins,

Chess and a little text file manipulation  Here's an image of a chess position: And that's about as close to image processing as today's blog post will come. Because this post is really about text processing.It seems like a lot of computational tasks in engineering and science involve manipulating data in text files. This weekend I had... read more >>

timeit makes it into MATLAB 4

Posted by Steve Eddins,

timeit makes it into MATLAB  This is my first blog post with "Published with MATLAB R2013b" at the bottom. The latest MATLAB release shipped earlier in September. And, for the first time in a while, a function that I wrote has made it into MATLAB.Back in 2008, I spent some time trying to incorporate performance... read more >>

Defining and filling holes on the border of an image 9

Posted by Steve Eddins,

Defining and filling holes on the border of an image Blog reader Alex asked a question this week about filling holes in this binary image.url = 'http://blogs.mathworks.com/images/steve/2013/eye-heart-matlab.png'; bw = imread(url); imshow(bw) Alex tried imfill but it didn't give him exactly what he was looking for.bw2 = imfill(bw,'holes'); imshow(bw2) title('Filling holes (first attempt)') Alex asked how he could fill the objects that are touching the... read more >>

Homomorphic filtering – part 2

Posted by Steve Eddins,

Homomorphic filtering – part 2 I'd like to welcome back guest blogger Spandan Tiwari for the second post in his two-part series on homomorphic filtering.Last time we looked at how to apply a simple homomorphic filter. Today we continue our discussion on homomorphic filtering. First I'll load the variables I, H, and Ihmf that I... read more >>

R2013a – image processing and computer vision 4

Posted by Steve Eddins,

R2013a – image processing and computer vision  I've mentioned the R2013a release in two previous posts (15-May-2013 and 12-Mar-2013). Today I want to point out that R2013a is a pretty significant release in terms of new features related to image processing and computer vision.Here's the quick summary of what's new in Image Processing Toolbox, Computer Vision System... read more >>

R2013a – Looking around in MATLAB 5

Posted by Steve Eddins,

R2013a – Looking around in MATLAB  The first MathWorks general product release of the year, R2013a, shipped a couple of months ago. I've already mentioned it once here in my 12-Mar-2013 post about the new MATLAB unit test framework.With each new release, I peruse the release notes for MATLAB to see what things I find particularly... read more >>

These postings are the author's and don't necessarily represent the opinions of MathWorks.