Steve on Image Processing

Concepts, algorithms & MATLAB

MATLAB image display – autoscaling values with imshow 2

Posted by Steve Eddins,


Last week I talked about displaying gray-scale and binary images. In that post, I showed how to control the grayscale range. For example, the call imshow(I,[0.4 0.6]) displays the matrix I as a gray-scale image so that the value 0.4 gets displayed as black, and the value 0.6 gets displayed... read more >>

MATLAB image display – grayscale and binary images

Posted by Steve Eddins,

In my previous posts (February 9, February 22, and February 29), I discussed the truecolor and indexed image display models in MATLAB, as well as the direct and scaled variations of indexed display. The Image Processing Toolbox has conventions for two additional image display models: grayscale and binary. These conventions are used by the MATLAB image display function imshow, which originated in the Image Processing Toolbox.... read more >>

MATLAB image display – scaled indexed images 1

Posted by Steve Eddins,


In my last post on pixel colors, I described the truecolor and indexed image display models in MATLAB, and I promised to talk to soon about a third model. That model is the scaled indexed image, a variation on the indexed image. The function imagesc is often used to display... read more >>

Image-based graphs

Posted by Steve Eddins,


Last time I showed you the basics of using the new graph theory functionality in MATLAB R2015b. Today I want to talk about some functions I put on the File Exchange for making graphs from images. Those of you working with graph-based image analysis algorithms might find them useful. I would be very interested in receiving feedback on these functions.... read more >>

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