Steve on Image Processing

Concepts, algorithms & MATLAB

The Future of String Arrays in MATLAB

Posted by Steve Eddins,

At MathWorks, we almost never talk in detail about product features before they are released. That's why this week's Art of MATLAB blog caught my eye. Guest blogger Dave Bergstein describes in some detail how we expect support for string arrays to evolve in the future. If you do a lot of data analysis or text processing in MATLAB, it is worth your while to take a look at Dave's post.... read more >>

The Eight Queens Problem 2

Posted by Steve Eddins,

Today I want to tackle a classic algorithm puzzle known as the Eight Queens Problem. In this problem, your task is to arrange eight queens on a chessboard so that none of the queens is attacking any of the others. Here is one solution.... read more >>

Logical indexing 3

Posted by Steve Eddins,

One of my favorite aspects of MATLAB for image processing is how I can use a binary image to index directly into a grayscale image. The technique is called logical indexing, and I'm going to show you how it works today.... read more >>

Gaussian filtering with imgaussfilt 2

Posted by Steve Eddins,

With the R2015a release a couple of years ago, the Image Processing Toolbox added the function imgaussfilt. This function performs 2-D Gaussian filtering on images. It features a heuristic that automatically switches between a spatial-domain implementation and a frequency-domain implementation.... read more >>

Aliasing and image resizing – part 3 4

Posted by Steve Eddins,

Today I'll try to wrap up my discussion about how aliasing affects image resizing and about how the imresize function tries to prevent it. (This is called antialiasing.) Let me show you where we are going. Here is the zone plate image I showed last time.... read more >>

Aliasing and image resizing – part 2 7

Posted by Steve Eddins,

In my 03-Jan-2017 post, I introduced my new topic: aliasing, especially as it relates to resizing images. Today I will get more specific about what aliasing actually is.... read more >>

MATLAB arithmetic expands in R2016b

Posted by Steve Eddins,

Earlier this summer, I was writing some color-space conversion code. At one point in the code, I had a Px3 matrix called RGB, which contained P colors, one per row. I also had a 1x3 vector, v. I needed to multiply each column of RGB by the corresponding element of... read more >>

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