Steve Eddins has developed MATLAB and image processing capabilities for MathWorks since 1993. He also coaches development teams on designing programming interfaces for engineers and scientists. Steve coauthored Digital Image Processing Using MATLAB.
For the geoscientists in the audience who are using my upslope area functions, I just updated the files. The update fixes a problem with the computation of influence and dependence maps for data sets that have NaNs outside the catchment area of interest. (Thanks to Claire for reporting the problem.) If you have data sets structured this way, you might want to download the revised files.