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Topic: Pixel Values to be identified
Replies: 8   Last Post: Apr 6, 2011 12:35 PM

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 Jamal Posts: 16 Registered: 3/16/11
Re: Pixel Values to be identified
Posted: Apr 6, 2011 11:54 AM

Dear Image Analyst,
after segmenting all the regions for all the blobs, can I choose 1 or 2 blobs in different locations with its mean intensities and change its mean intensity to my own value.

I can see in the Mat Lab command a list of mean intensity values, can these intensity values be controlled and choose my desired blob and change it to different values.

Regards

ImageAnalyst <imageanalyst@mailinator.com> wrote in message <cf2e33d5-d5d0-4dbc-af54-b11ccf4714c0@f11g2000vbx.googlegroups.com>...
> Alright, step by step now. What does
> allBlobIntensities - targetIntensity
> do? It finds the difference between all of the intensities of all of
> your objects, and the "target intensity" of the one object that you
> are trying to find matches for. Let's say that your target intensity
> is 100, and let's say that your mean intensities of 5 objects are
> allBlobIntensities = [90.1, 95.1, 100.1, 105.1, 110.8]
>
> Now let's do
> targetIntensity = 100;
> allBlobIntensities - targetIntensity
> This is what you get:
> -9.9000 -4.9000 0.1000 5.1000 10.8000
>
> Now, which of those do you say matches close enough? Any of them?
> Just the 100.1? Maybe the 95.1 and 105.1 also? Let's say that we
> wanted to say that anything within 6 gray levels "matched" the target
> intensity well enough. But do you want only positive differences?
> Probably not. So how can we get matches for both positive and
> negative differences? How about using the abs() function? So now
> everything is explained, and the final code is:
>
> allBlobIntensities = [90.1, 95.1, 100.1, 105.1, 110.8];
> targetIntensity = 100;
> differences = allBlobIntensities - targetIntensity
> tolerance = 6
> matchesIntensity = abs(differences) < tolerance
>
> differences =
> -9.9000 -4.9000 0.1000 5.1000 10.8000
> tolerance =
> 6
> matchesIntensity =
> 0 1 1 1 0

Date Subject Author
4/3/11 Jamal
4/3/11 ImageAnalyst
4/3/11 Jamal
4/3/11 ImageAnalyst
4/3/11 Jamal
4/3/11 ImageAnalyst
4/3/11 Jamal
4/6/11 Jamal
4/6/11 ImageAnalyst