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From: Maxx Chatsko on 9 Jul 2010 15:06
"Image Analyst" <imageanalyst(a)mailinator.com>
> Maxx:
> Put tic and toc around your imread function to see how much time it takes. You're still having imread read a 2D tiff image, right? Unless you have gigabytes of data and a 3D image (which I'm not sure imread supports) then it shouldn't take that long. I can read a 67 MB image (9000 by 7000 pixels), which is probably bigger than yours, in only 3 seconds. Now if I were reading in 50 of these big images, it would take 150 seconds, but just a single call to imread only takes 3 seconds.

I really appreciate your time and help. I will check out your suggestion and post back if I have any questions.
Maxx
From: Maxx Chatsko on 9 Jul 2010 16:07
"Image Analyst" <imageanalyst(a)mailinator.com>
> Put tic and toc around your imread function to see how much time it takes. You're still having imread read a 2D tiff image, right? Unless you have gigabytes of data and a 3D image (which I'm not sure imread supports) then it shouldn't take that long. I can read a 67 MB image (9000 by 7000 pixels), which is probably bigger than yours, in only 3 seconds. Now if I were reading in 50 of these big images, it would take 150 seconds, but just a single call to imread only takes 3 seconds.

Time Calls Line
1 function [X,map] = readtif(filename, varargin)
192.37 2382 52 [X, map, details] = rtifc(args);

My largest image is 2380 KB. I thought perhaps the calls and size were too similar to be coincidence, but I ran the function with an image of half the size and it still calls the rtifc 2382 times. The images being passed to imread are in fact 3D hyperspectral images.
From a function that reads 3D info from .tif images (thus the image3D - our datacube)
204.42 2382 65 image3d(:,:,k) = imread(fileName, k);
(the 192.37s is included in the 204.42s directly above)
From: Image Analyst on 9 Jul 2010 16:23
I don't have the function readtif() - is that one you wrote yourself? I also don't know rtifc. Why is rtifc being called 2,382 times? Do you have 2,382 2D TIF images?
From: Steven Lord on 9 Jul 2010 16:44

"Image Analyst" <imageanalyst(a)mailinator.com> wrote in message
news:i180f9$2md$1(a)fred.mathworks.com...
>I don't have the function readtif() - is that one you wrote yourself? I
>also don't know rtifc. Why is rtifc being called 2,382 times? Do you have
>2,382 2D TIF images?

Both READTIF and RTIFC are private helper functions -- you should have them
in your installation, but they are not intended to be called directly.

http://www.mathworks.com/access/helpdesk/help/techdoc/matlab_prog/f4-70335.html

--
Steve Lord
slord(a)mathworks.com
comp.soft-sys.matlab (CSSM) FAQ: http://matlabwiki.mathworks.com/MATLAB_FAQ
To contact Technical Support use the Contact Us link on
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From: Maxx Chatsko on 9 Jul 2010 22:09
"Image Analyst" <imageanalyst(a)mailinator.com>
> I don't have the function readtif() - is that one you wrote yourself? I also don't know rtifc. Why is rtifc being called 2,382 times? Do you have 2,382 2D TIF images?

Not sure why its calling it 2,382 times. I'm reviewing all of the code we use here because it could obviously be made faster. readtif() is from MathWorks, and rtifc seems to be a MEX file (and the culprit) that is within readtif().
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