MATLAB Help

Academia Nut · Post by **Academia Nut** » 2008-04-09 09:55am

This might go better in G&C or in Testing, but I figured since its math and science related here would be the best place for it. Anyway, I'm trying to use MATLAB to do a Fourier transform on images, but I can't find anything on how to actually get images into MATLAB so that I can perform the transform on them, because I have found a function to do that and then do the inverse transform. So for all of you out there with more experience with the program, how exactly can I import and/or create images in MATLAB. Also, since this is for a spatial filtering lab, how do I edit images? I figure that would probably go along with my first question, but you never can tell.

Wyrm · Post by **Wyrm** » 2008-04-09 10:29am

imread and imwrite is for the basic image I/O — consult their help files. I do know you need to convert the matrix produced by imread to a double matrix to do any sort of math with it. I'm not sure what to use to convert the image back to an image format for imwrite (it's been too damn long).

fnord · Post by **fnord** » 2008-04-09 10:37am

imread may be what you're looking for. What type of image(s) are you trying to load?

Academia Nut · Post by **Academia Nut** » 2008-04-09 12:07pm

Hey thanks, that really helped. Mostly I'm trying to load simple black and white images for the purposes of examining how the various image gratings and such are transformed.

Nephtys · Post by **Nephtys** » 2008-04-09 03:14pm

imwrite(variable,'filename.ext') I believe is the syntax, but you can look it up with doc inwrite.

raptor3x · Post by **raptor3x** » 2008-04-09 05:09pm

On a side note, I'm not sure how long your Fourier transforms are taking or how many you have to do, but if you have the equipment (Nvidia 8800 or greater series video card) you should try their matlab CUDA plugin. Incredible speedup over a regular CPU.