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Re: Area measurement

Posted by fra-off on Sep 08, 2009; 8:46am
URL: http://imagej.273.s1.nabble.com/Area-measurement-tp3691257p3691261.html

If I will find a method to do this automatically I will be crazy for happiness!
But I will be happy even finding some resolution for only one slice.
Anyway, even filtering, or using Despeckle, the problem still exist.
I think that I have to find some command or plugin to differentiate to distinct material that have similar grey value
Regard your question, the "bands" are covering of gypsum around calcite grains. And every grain have different thickness of gypsum. Every picture represent a slice perpendicular to z axis of a reactor.I sent a detail because in normal size you can not see the bands

Best regards

Francesco


Gluender-3 wrote
Francesco,

I fear you won't find an approach for the automatic isolation of the "bands".

You'll always need to manually adjust some parameters.


>Thank you for your quick response!
>
>unfortunately I still have the problem beacause a lot of structures in the
>full picture have values around 112 and furthermore I have more than 1300
>slices for sample....and every slice have little different value for the
>"bands". You can find for example  99, 103, 112........

I wrote:
"... of course you will have to set the correct threshold for every
image by hand."

>Francesco
>Gluender-3 wrote:
>>
>>  Francesco,
>>
>>  for a first try I've applied two times "Process>Noise>Despeckle" to
>>  your JPG-sample. Then I've chosen a threshold at value 112. With this
>  > setting a separation is possible but of course you will have to set
>  > the correct threshold for every image by hand.
>>
>>  Furthermore, you will have to close the ends of your "bands of
>>  interest" by hand and then apply the wand tool.
>>
>>>Dear experts
>>>
>>>I have a big image sequence coming from micro-tomografy analysis. I need
>to
>>>calculate the area of some structures that have a gery value very similar
>to
>>>other structures (see the picture, I need the thin layer between arrows).
>So
>>>when I spotlight this structures by Histogram and Thereshold, I can not
>>>separate it from other parts that have similar grey values. Finally the
>>>measurament is terribly overstimate.
>>>Do you know some trick to resolve my problem?
>>>
>>>Thank you
>>>
>>>Francesco
>  >>http://n2.nabble.com/file/n3598079/mct_fra.jpg mct_fra.jpg
>
>  > HTH
>>  --
>>
>>                     Herbie
>>
>>            ------------------------
>  >           <http://www.gluender.de>
>

In fact there is more than human vision that you would need to solve
the problem, you'll need specific human knowledge as well...
For instance to solve the problem: Where do the bands end?

Best
--

                   Herbie

          ------------------------
          <http://www.gluender.de>