Measuring Volume

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Measuring Volume

Aaron Johnson-9
Hello, I'm interested in finding a way to do a volume measurement of an 8-
bit grayscale stack (usually between 15-20 images) coming from a confocal
microscope.  The structure I'm measuring (ACh receptor) is fairly
contiguous and could be characterized as blob-shaped.  My main questions
are:

1) What are your recommendations regarding thresholding?  I always want to
capture the max (255), and am more concerned about finding an automated
way of finding the minimum.  The "auto-threshold" doesn't work for me.

2) What do you recommend for the volume measurement?  I've tried voxel
counter with some success, but I'm wondering if there are other easy ways
to do this, if for no other reason than to confirm my measurements with
voxel counter.

Thanks!
Aaron
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Re: Measuring Volume

Justin McGrath
Does the autothreshold not work because it doesn't include 255?  If
that's the problem, you can use
setAutoThreshold();
getThreshold(lower,upper);
setThreshold(lower,255);

Which would get the bottom cutoff automatically then set the upper to
255.  If the bottom cutoff isn't good, then you might try some of the
threshold plugins listed on the ImageJ website, or you can come up
with your own criterion and make a macro or plugin for it.  I wrote a
macro once that cut off the leftmost peak of the histogram, which in
my images was always unwanted.  I could find it if sounds useful to
you.  However, it's kind of shoddy coding.

Justin

On Dec 6, 2007 9:47 AM, Aaron Johnson <[hidden email]> wrote:

> Hello, I'm interested in finding a way to do a volume measurement of an 8-
> bit grayscale stack (usually between 15-20 images) coming from a confocal
> microscope.  The structure I'm measuring (ACh receptor) is fairly
> contiguous and could be characterized as blob-shaped.  My main questions
> are:
>
> 1) What are your recommendations regarding thresholding?  I always want to
> capture the max (255), and am more concerned about finding an automated
> way of finding the minimum.  The "auto-threshold" doesn't work for me.
>
> 2) What do you recommend for the volume measurement?  I've tried voxel
> counter with some success, but I'm wondering if there are other easy ways
> to do this, if for no other reason than to confirm my measurements with
> voxel counter.
>
> Thanks!
> Aaron
>
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Re: Measuring Volume

Aaron Johnson-9
In reply to this post by Aaron Johnson-9
That ought to fix my problem with the autothreshold - thanks, Justin.  
Anybody have any advice regarding the volume measurement?
Aaron

On Thu, 6 Dec 2007 14:12:20 -0600, Justin McGrath <[hidden email]>
wrote:

>Does the autothreshold not work because it doesn't include 255?  If
>that's the problem, you can use
>setAutoThreshold();
>getThreshold(lower,upper);
>setThreshold(lower,255);
>
>Which would get the bottom cutoff automatically then set the upper to
>255.  If the bottom cutoff isn't good, then you might try some of the
>threshold plugins listed on the ImageJ website, or you can come up
>with your own criterion and make a macro or plugin for it.  I wrote a
>macro once that cut off the leftmost peak of the histogram, which in
>my images was always unwanted.  I could find it if sounds useful to
>you.  However, it's kind of shoddy coding.
>
>Justin
>
>On Dec 6, 2007 9:47 AM, Aaron Johnson <[hidden email]> wrote:
>> Hello, I'm interested in finding a way to do a volume measurement of an
8-
>> bit grayscale stack (usually between 15-20 images) coming from a
confocal
>> microscope.  The structure I'm measuring (ACh receptor) is fairly
>> contiguous and could be characterized as blob-shaped.  My main questions
>> are:
>>
>> 1) What are your recommendations regarding thresholding?  I always want
to
>> capture the max (255), and am more concerned about finding an automated
>> way of finding the minimum.  The "auto-threshold" doesn't work for me.
>>
>> 2) What do you recommend for the volume measurement?  I've tried voxel
>> counter with some success, but I'm wondering if there are other easy
ways
>> to do this, if for no other reason than to confirm my measurements with
>> voxel counter.
>>
>> Thanks!
>> Aaron
>>
>=========================================================================