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What is intensity image?

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Wenlong

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Apr 14, 2012, 12:39:23 PM4/14/12
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Dear all,

Can I have the definition of intensity image? Is it the same as gray-level image?

Thank you very much for your kindly help.

Best wishes
Wenlong

Matt J

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Apr 14, 2012, 2:36:28 PM4/14/12
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"Wenlong" wrote in message <jmc97r$qms$1...@newscl01ah.mathworks.com>...
> Dear all,
>
> Can I have the definition of intensity image? Is it the same as gray-level image?
>
============

It doesn't sound like a term whose definition is widely standardized.

ImageAnalyst

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Apr 14, 2012, 7:40:46 PM4/14/12
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----------------------------------------------------------------------
Probably yes, for you. Though gray scale can be any quantity, such as
height for a profilometer image, concentration for chemical images,
density for x-ray images, etc., not just optical intensity.

Tony

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May 25, 2012, 5:24:27 PM5/25/12
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I remember from a radiometry book, that anyone who uses the word intensity either means to be ambiguous on purpose, or does not know what they are talking about.

Basically, no, there is no clear definition that will fit all branches of science.

ImageAnalyst

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May 25, 2012, 7:32:30 PM5/25/12
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On May 25, 5:24 pm, "Tony " <tony_burba_w_i...@wahoo.com> wrote:
> I remember from a radiometry book, that anyone who uses the word intensity either means to be ambiguous on purpose, or does not know what they are talking about.
>
> Basically, no, there is no clear definition that will fit all branches of science.

--------------------------------------------------------------------------------------
Well, not _everyone_ but almost. You're right about that its one of
those generic layman-type terms that everyone wants to use for
everything. See a list of most of them on Wikipedia.
http://en.wikipedia.org/wiki/Intensity
The field of optics/radiometry is probably the most exact in its usage
and definitions because it has to be.

The late Jim Palmer (my old Professor of Optical Sciences at the
College of Optical Sciences of the University of Arizona) was
particularly irked by the sloppy use of this term, even by those who
ought to know better, and that spurred him to write "Getting Intense
on Intensity":
http://www.optics.arizona.edu/Palmer/intenopn.html

The "true" units of intensity, defined by SI are "flux per steradian."
Flux can be watts or lumens depending on whether you're talking about
all wavelengths, or just visible wavelengths respectively. But that's
too complicated for laymen so, sadly, they make up whatever definition
they want, and that's when the ambiguity/uncertainty starts.

xiaowen...@gmail.com

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May 3, 2014, 2:46:58 AM5/3/14
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I have the same question !
Thank god let me find your discussion there. Now I konw how to uderstand it.In my case it's similar to grayscale images.

Bella

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Jun 18, 2014, 11:04:08 AM6/18/14
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"Tony " <tony_bur...@wahoo.com> wrote in message <jpotab$dqa$1...@newscl01ah.mathworks.com>...
> I remember from a radiometry book, that anyone who uses the word intensity either means to be ambiguous on purpose, or does not know what they are talking about.
>
> Basically, no, there is no clear definition that will fit all branches of science.

Then what does it mean in context of MATLAB documentation? In most entries for the Image Processing Toolbox, such as this one:

http://www.mathworks.com/help/images/ref/im2uint16.html

they refer to the variable I as an "intensity image", but are unclear as to what this refers to.

Bella

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Jun 18, 2014, 11:05:09 AM6/18/14
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"Wenlong" wrote in message <jmc97r$qms$1...@newscl01ah.mathworks.com>...
MATLAB defines it here:

http://www.mathworks.com/help/matlab/creating_plots/image-types.html#f2-175
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