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Integrated Density?

Kashif Zeeshan
Hello experts,

Can you kindly help me to understand the term "Integrated Density". I read
the documentation of ImageJ which says that this is the sum of all the
pixels or equals to the product of Area and Mean Gray Value. But it is very
confusing for me. How we will interpret this? What is the difference between
density and integrated density in this regard? Is this term "integrated
density" is same as "density"? My aim is to compare the different media
giving different forms of fungi according to the density of the pellets
found in each medium and also if this is possible then I want to classify
the pellets in a medium according to the density i.e., I want to classify
pellets as less dense, average dense and dense.
Any help will be highly appreciated.

Kashif ZEESHAN
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Re: Integrated Density?

Robert Dougherty
Kashif,

Maybe this will help: density is an intensive quantity and integrated  
density is an extensive quantity.  See  Wikipedia for an explanation  
of extensive and intensive quantities.

Bob


Robert Dougherty, Ph.D.
President, OptiNav, Inc.
10900 NE 8th St, Suite 900
Bellevue, WA 98004
Tel. (425)990-5912
FAX (425)467-1119
www.optinav.com
[hidden email]
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Re: Integrated Density?

Ben Tupper
On Aug 28, 2008, at 12:01 PM, Kashif Zeeshan wrote:

> Hello experts,
>
> Can you kindly help me to understand the term "Integrated Density".  
> I read
> the documentation of ImageJ which says that this is the sum of all the
> pixels or equals to the product of Area and Mean Gray Value. But it  
> is very
> confusing for me. How we will interpret this? What is the  
> difference between
> density and integrated density in this regard? Is this term  
> "integrated
> density" is same as "density"? My aim is to compare the different  
> media
> giving different forms of fungi according to the density of the  
> pellets
> found in each medium and also if this is possible then I want to  
> classify
> the pellets in a medium according to the density i.e., I want to  
> classify
> pellets as less dense, average dense and dense.
> Any help will be highly appreciated.
>
> Kashif ZEESHAN

On Aug 28, 2008, at 7:22 PM, Robert Dougherty wrote:

> Kashif,
>
> Maybe this will help: density is an intensive quantity and  
> integrated density is an extensive quantity.  See  Wikipedia for an  
> explanation of extensive and intensive quantities.
>

Hi,

I find it a bit hard to untangle the questions posed.  But here are  
couple of thoughts...

(1) Be sure that you understand what the documentation actually says,  
"The sum of the values of the pixels in the image or selection."  In  
your case, it means that it sums the gray values of each pellet found  
- it is a measure of "grayness" on an individual particle or  
selection. (see http://rsb.info.nih.gov/ij/docs/menus/analyze.html#set )

(2) Your description of pellet counting could be used to measure a  
density of population - for example, X pellets per square cm. You can  
use ImageJ for this purpose.  For that you could analyze the image  
and retrieve either the number of pellets found.  Dividing the pellet  
count by the image area will give you the population density.  If you  
want to discriminate density patterns within an image, then you might  
want to dig deeper by retrieving the centroids of each pellet.  You  
could divide the image into quadrants of known area and get the  
population density in each quadrant, etc.

If I follow you correctly, I don't think you want the Integrated  
Density as you won't care how dark each pellet is.

Cheers,
Ben



Ben Tupper
Bigelow Laboratory for Ocean Science
180 McKown Point Road
POB 475
West Boothbay Harbor, ME 04575
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Re: Integrated Density?

Kashif Zeeshan
Thanks to all for the reply. In fact, my aim is to determine the density of
each object. I thought that I choose the wrong option. Instead of
calculating integrated density, I should have measure mean gray value which
shows the density. Correct me please if I am wrong. For the moment, I will
divide the integrated density values by area values to have the density (or
mean gray values). Can you kindly tell me what will be the unit of the
density or gray values here.

Cordially.

Kashif ZEESHAN

-----Message d'origine-----
De : ImageJ Interest Group [mailto:[hidden email]] De la part de Ben
Tupper
Envoyé : vendredi 29 août 2008 02:52
À : [hidden email]
Objet : Re: Integrated Density?

On Aug 28, 2008, at 12:01 PM, Kashif Zeeshan wrote:

> Hello experts,
>
> Can you kindly help me to understand the term "Integrated Density".  
> I read
> the documentation of ImageJ which says that this is the sum of all the
> pixels or equals to the product of Area and Mean Gray Value. But it  
> is very
> confusing for me. How we will interpret this? What is the  
> difference between
> density and integrated density in this regard? Is this term  
> "integrated
> density" is same as "density"? My aim is to compare the different  
> media
> giving different forms of fungi according to the density of the  
> pellets
> found in each medium and also if this is possible then I want to  
> classify
> the pellets in a medium according to the density i.e., I want to  
> classify
> pellets as less dense, average dense and dense.
> Any help will be highly appreciated.
>
> Kashif ZEESHAN

On Aug 28, 2008, at 7:22 PM, Robert Dougherty wrote:

> Kashif,
>
> Maybe this will help: density is an intensive quantity and  
> integrated density is an extensive quantity.  See  Wikipedia for an  
> explanation of extensive and intensive quantities.
>

Hi,

I find it a bit hard to untangle the questions posed.  But here are  
couple of thoughts...

(1) Be sure that you understand what the documentation actually says,  
"The sum of the values of the pixels in the image or selection."  In  
your case, it means that it sums the gray values of each pellet found  
- it is a measure of "grayness" on an individual particle or  
selection. (see http://rsb.info.nih.gov/ij/docs/menus/analyze.html#set )

(2) Your description of pellet counting could be used to measure a  
density of population - for example, X pellets per square cm. You can  
use ImageJ for this purpose.  For that you could analyze the image  
and retrieve either the number of pellets found.  Dividing the pellet  
count by the image area will give you the population density.  If you  
want to discriminate density patterns within an image, then you might  
want to dig deeper by retrieving the centroids of each pellet.  You  
could divide the image into quadrants of known area and get the  
population density in each quadrant, etc.

If I follow you correctly, I don't think you want the Integrated  
Density as you won't care how dark each pellet is.

Cheers,
Ben



Ben Tupper
Bigelow Laboratory for Ocean Science
180 McKown Point Road
POB 475
West Boothbay Harbor, ME 04575
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Re: Integrated Density?

Gluender-2
Dear all,

since long I'm repeatedly irritated by the expression density in this context.

The reason is that it can be confused with
"optical density" of film that is the logarithm
of its "inverse transparency" = "opacity".

Of course in the first place, density denotes an
entity referred to mostly a spatial extent, such
as an area or volume, e.g.
(Carbon-Atoms)/(Cubic-Angstrom))

Best

Herbie


>Thanks to all for the reply. In fact, my aim is to determine the density of
>each object. I thought that I choose the wrong option. Instead of
>calculating integrated density, I should have measure mean gray value which
>shows the density. Correct me please if I am wrong. For the moment, I will
>divide the integrated density values by area values to have the density (or
>mean gray values). Can you kindly tell me what will be the unit of the
>density or gray values here.
>
>Cordially.
>
>Kashif ZEESHAN
>
>-----Message d'origine-----
>De : ImageJ Interest Group [mailto:[hidden email]] De la part de Ben
>Tupper
>Envoyé : vendredi 29 août 2008 02:52
>À : [hidden email]
>Objet : Re: Integrated Density?
>
>On Aug 28, 2008, at 12:01 PM, Kashif Zeeshan wrote:
>>  Hello experts,
>>
>>  Can you kindly help me to understand the term "Integrated Density".
>>  I read
>>  the documentation of ImageJ which says that this is the sum of all the
>>  pixels or equals to the product of Area and Mean Gray Value. But it
>>  is very
>>  confusing for me. How we will interpret this? What is the
>>  difference between
>>  density and integrated density in this regard? Is this term
>>  "integrated
>>  density" is same as "density"? My aim is to compare the different
>>  media
>>  giving different forms of fungi according to the density of the
>>  pellets
>>  found in each medium and also if this is possible then I want to
>>  classify
>>  the pellets in a medium according to the density i.e., I want to
>>  classify
>>  pellets as less dense, average dense and dense.
>>  Any help will be highly appreciated.
>>
>>  Kashif ZEESHAN
>
>On Aug 28, 2008, at 7:22 PM, Robert Dougherty wrote:
>
>>  Kashif,
>>
>>  Maybe this will help: density is an intensive quantity and
>>  integrated density is an extensive quantity.  See  Wikipedia for an
>>  explanation of extensive and intensive quantities.
>>
>
>Hi,
>
>I find it a bit hard to untangle the questions posed.  But here are
>couple of thoughts...
>
>(1) Be sure that you understand what the documentation actually says,
>"The sum of the values of the pixels in the image or selection."  In
>your case, it means that it sums the gray values of each pellet found
>- it is a measure of "grayness" on an individual particle or
>selection. (see http://rsb.info.nih.gov/ij/docs/menus/analyze.html#set )
>
>(2) Your description of pellet counting could be used to measure a
>density of population - for example, X pellets per square cm. You can
>use ImageJ for this purpose.  For that you could analyze the image
>and retrieve either the number of pellets found.  Dividing the pellet
>count by the image area will give you the population density.  If you
>want to discriminate density patterns within an image, then you might
>want to dig deeper by retrieving the centroids of each pellet.  You
>could divide the image into quadrants of known area and get the
>population density in each quadrant, etc.
>
>If I follow you correctly, I don't think you want the Integrated
>Density as you won't care how dark each pellet is.
>
>Cheers,
>Ben
>
>
>
>Ben Tupper
>Bigelow Laboratory for Ocean Science
>180 McKown Point Road
>POB 475
>West Boothbay Harbor, ME 04575
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