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From: Maxx Chatsko on 9 Jul 2010 11:52
"Mark Hayworth" <hayworth(a)none.com>
> I never use feval and I deal with images constantly in every app I develop. The help says "Note It is not necessary to use feval to call a function by means of a function handle. This is explained in in the MATLAB Programming Fundamentals documentation." Why do you think you need to use feval? Why not just call the function directly?
> -ImageAnalyst

Its actually part of the MatLab function imread.m towards the end of the code...
From: Walter Roberson on 9 Jul 2010 12:03
Maxx Chatsko wrote:
> "Mark Hayworth" <hayworth(a)none.com>
>> I never use feval and I deal with images constantly in every app I
>> develop. The help says "Note It is not necessary to use feval to
>> call a function by means of a function handle. This is explained in
>> in the MATLAB Programming Fundamentals documentation." Why do you
>> think you need to use feval? Why not just call the function directly?
>> -ImageAnalyst
>
> Its actually part of the MatLab function imread.m towards the end of
> the code...

Ah, the invocation of the routine that does the format-specific reading...
From: Image Analyst on 9 Jul 2010 12:46
Maxx:
Tell us about your images. I don't have any 2D images that take 150 seconds to read in with imread, so I'm wondering why yours do.
From: Maxx Chatsko on 9 Jul 2010 13:20
"Image Analyst" <imageanalyst(a)mailinator.com>
> Tell us about your images. I don't have any 2D images that take 150 seconds to read in with imread, so I'm wondering why yours do.

They're 3D hyperspectral datacubes (.tif) and imread is part of one of our functions. But I think the problem is within the mainfunction and gui initialization code - when you're in profiler and select a link it shows you the time for the function/task and its children. So the farthest I can go in the children list (until there are no more links) is that line in imread. This program was created with guide, so is the auto-generated code the problem? Cause it has feval and some silly gui_mainfcn lines...I'm trying to edit it but it doesn't like it.
Maxx
From: Image Analyst on 9 Jul 2010 14:39
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.
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