Re: Improving Particle Analyzer accuracy

Posted by Matthew Moore on
URL: http://imagej.273.s1.nabble.com/Improving-Particle-Analyzer-accuracy-tp4999626p4999670.html

On 02/08/12 11:06, Gabriel Landini wrote:

>> The main problem is that the 'Make binary' that you have to use before
>> running the particle analyzer introduces lots of noise into the image,
>> so it picks up lots of false positives.
> In that case you could process the image before thresholding or after.
>
> Before: there are many filters that you can try: smoothing (mean, Gaussian),
> median, morphological (greyscale closing/opening).
>
> During: you could to try different methods for the actual thresholding step
> (and IJ supports quite a few) or some other pixel classification.
>
> After: binary closing/opening, filter by size, opening and closing by
> reconstruction, median, etc.
>
> You need to be aware that by any of that processing, you are changing the
> original data.
>
>>  The dots are quite obvious really, it's a plain white
>> piece of paper with black blobs on it.
> I guess that probably the dots are not the problem, but the image or
> background is not completely white, and the thresholding level that you are
> using picks some of that intensity variation as "object".

If I were to send some sample images over is there anyone on the list
who might be able to take a look at them and see if they might be able
to suggest a suitable set of thresholds/filters etc?

I've been slowly working through a massive combination of filters and
settings, to try and improve accuracy, but have had no success so far.

Thanks,

Matt

--
Matthew Moore
Surgical Materials Testing Laboratory
System Administrator
Telephone: [phone]
Email: [hidden email]

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