Steve on Image Processing and MATLAB

Concepts, algorithms & MATLAB

Results for: 2007

Upslope area – Summary

Back in March I started writing about an algorithm implementation experiment for computing upslope area. Given an "image" whose pixel values are terrain elevations, the upslope area of a pixel is the area of the uphill terrain that drains through that pixel. I chose a paper that looked promising, and... read more >>

Finding bright objects 7

In a blog comment earlier this summer, someone asked how to find "which labeled regions have a bright spot greater than some threshold?" That's a good question. It can be done efficiently and compactly using the Image Processing Toolbox, but the techniques ... read more >>

Upslope area – handling NaNs 2

Since I originally posted my upslope toolbox to MATLAB Central back in August, I have heard from some experts about an issue related to NaNs in the DEM data. Specifically, some data sets record elevation only for DEM pixels within a particular catchment basin.... read more >>

Category and archive links 2

We recently changed the view when you click on a category in the sidebar on the right. I haven't used categories much, but the other bloggers (Loren on the Art of MATLAB, Doug's Pick of the Week, and Inside the MATLAB Desktop) have been. ... read more >>

HDR and tone mapping links 12

In photography and color science, MathWorks developer Jeff Mather's personal interests intersect with his work. He guest-blogged here last year with a post about the CIE Standard Observer. Earlier this month, he posted on his personal blog about high dynamic range (HDR) imaging and associated tone mapping algorithms. If you... read more >>