[Insight-users] hysteresis thresholding, local maxima filter

[Luis Ibanez]

Hi Gwen,

You are probably not using  the most
recent CVS checkout. In the current one

ThreadedCompute2ndDerivativePos() is in line 557
HysteresisThresholding() is in line 393

http://www . itk . org/cgi-bin/cvsweb . cgi/Insight/Code/BasicFilters/itkCannyEdgeDetectionImageFilter . txx?annotate=1 . 42&cvsroot=Insight


We could include the Hysteresis threshold on the
wish list of classes to be implemented in the
near future.



    Regards


      Luis


-----------------------
Gwenaël Guillard wrote:
> Hi Luis,
> 
> At this line I've got the method ThreadedCompute2ndDerivativePos(...), 
> not HysteresisThresholding().
> I would like to use such a method outside the Canny edge detection 
> framework.
> 
> Gwen
>  
>  
>  
> 
> Luis Ibanez a écrit :
> 
>> Hi Gwen,
>>
>> Hysteresis thresholding is implemented as part of the
>> CannyEdgeDetectionImageFilter
>> http://www . itk . org/Insight/Doxygen/html/classitk_1_1CannyEdgeDetectionImageFilter . html 
>>
>>
>> Please take a look at the method HyteresisThresholding() in
>> itkCannyEdgeDetectionImageFilter.txx line 393
>>
>> Do you need to apply this operation outside of the Canny edge
>> detection framework ?
>>
>> -- 
>>
>> Local maxima is detected used zero crossings on a second derivative
>> image (e.g. the Laplacian)
>>
>> Pure Zero crossing is implemented in
>> http://www . itk . org/Insight/Doxygen/html/classitk_1_1ZeroCrossingImageFilter . html 
>>
>>
>> Zero crossing of the laplacian is implemented in
>> http://www . itk . org/Insight/Doxygen/html/classitk_1_1ZeroCrossingBasedEdgeDetectionImageFilter . html 
>>
>>
>> Regards,
>>
>>      Luis
>>
>> -----------------------
>> Gwenaël Guillard wrote:
>> > Hi,
>> >
>> > Is hysteresis thresholding implemented under another name? Or did I 
>> miss
>> > it in the documentation?
>> > The same question for a local maxima filter.
>> >
>> > Thank you for your answers,
>> >
>> > Gwen
>> >
>> > _______________________________________________
>> > Insight-users mailing list
>> > Insight-users at itk . org
>> > http://www . itk . org/mailman/listinfo/insight-users
>> >
>>
> -- 
> -----------------------------------------------------------
> Gwenael Guillard
> Doctorant
> Departement Image et Traitement de l'Information (ITI)
> LAboratoire  de Traitement de l'Information Medicale (LATIM) - INSERM ERM 0102
> ENST Bretagne
> Technopole Brest Iroise
> BP 832 - 29285 Brest Cedex
> Tel : 02 29 00 13 01
> email : gwenael . guillard at enst-bretagne . fr, g . guillard at ieee . org
> 
>