[Insight-users] itk::PCAShapeSignedDistanceFunction

[Lucas Lorenzo]

--Apple-Mail-1--539876014
Content-Transfer-Encoding: 7bit
Content-Type: text/plain;
	charset=US-ASCII;
	format=flowed

Thanks Lydia,

what I'm doing right now is using an ImageConstIteratorWithIndex to 
iterate over a FeatureImageType image and at each iteration step I'm 
getting the index (GetIndex()) so as to evaluate the  
PCAShapeSignedDistanceFunction. Then, if the signe distance function 
value is within the window I've already defined, I perform other 
operations using the FeatureImage values.

So, the previous process works but very slowly.

Is there a way to iterate directly over the  
PCAShapeSignedDistanceFunction, getting the index ONLY when the signed 
distance value is within the window (calling this way  method 
GetIndex() a few times) ? This way I assume the process would be much 
faster.

Thanks,

Lucas


On Apr 1, 2004, at 11:54 AM, Lydia Ng wrote:

> Lucas,
>
> I don't believe there is apart from polling one pixel at a time.
>
> Even if you use a combination of filters
> SpatialFunctionImageEvaluatorFilter->BinaryThresholdImageFilter you 
> will
> still need to eventually visit every pixel to find which is within 
> range.
>
> - Lydia
>
>> -----Original Message-----
>> From: Lucas Lorenzo [mailto:lucas at cvrti.utah.edu]
>> Sent: Thursday, April 01, 2004 9:53 AM
>> To: ITK
>> Subject: [Insight-users] itk::PCAShapeSignedDistanceFunction
>>
>> Hi all,
>>
>> sorry for insisting but I do not give up yet.
>> Does anyone know of a fast, efficient way to get the indexes of those
>> pixels falling within a particular window (lets call them low_val and
>> high_val) from a PCAShapeSignedDistanceFunction ?
>> Thanks,
>>
>> Lucas
>>
>> Lucas Lorenzo
>>
>> University of Utah
>> Nora Eccles Harrison CardioVascular Research and Training Institute
>> Fellows Room
>> 95 South 2000 East
>> Salt Lake City, UT 84112-5000
>>
>> e-mail:  lucas at cvrti.utah.edu
>> telephone: 801-587-9536
>>
>> _______________________________________________
>> Insight-users mailing list
>> Insight-users at itk.org
>> http://www.itk.org/mailman/listinfo/insight-users
> _______________________________________________
> Insight-users mailing list
> Insight-users at itk.org
> http://www.itk.org/mailman/listinfo/insight-users
>
Lucas Lorenzo

University of Utah
Nora Eccles Harrison CardioVascular Research and Training Institute
Fellows Room
95 South 2000 East
Salt Lake City, UT 84112-5000

e-mail:  lucas at cvrti.utah.edu
telephone: 801-587-9536

--Apple-Mail-1--539876014
Content-Transfer-Encoding: 7bit
Content-Type: text/enriched;
	charset=US-ASCII

Thanks Lydia,


what I'm doing right now is using
an<color><param>0000,0000,0000</param> ImageConstIteratorWithIndex</color>
to iterate over a FeatureImageType image and at each iteration step
I'm getting the index (GetIndex()) so as to evaluate the 
PCAShapeSignedDistanceFunction. Then, if the signe distance function
value is within the window I've already defined, I perform other
operations using the FeatureImage values.


So, the previous process works but very slowly. 


Is there a way to iterate directly over the 
PCAShapeSignedDistanceFunction, getting the index ONLY when the signed
distance value is within the window (calling this way  method
GetIndex() a few times) ? This way I assume the process would be much
faster.


Thanks,


Lucas



On Apr 1, 2004, at 11:54 AM, Lydia Ng wrote:


<excerpt>Lucas,


I don't believe there is apart from polling one pixel at a time.


Even if you use a combination of filters

SpatialFunctionImageEvaluatorFilter->BinaryThresholdImageFilter you
will

still need to eventually visit every pixel to find which is within
range.


- Lydia


<excerpt>-----Original Message-----

From: Lucas Lorenzo [mailto:lucas at cvrti.utah.edu]

Sent: Thursday, April 01, 2004 9:53 AM

To: ITK

Subject: [Insight-users] itk::PCAShapeSignedDistanceFunction


Hi all,


sorry for insisting but I do not give up yet.

Does anyone know of a fast, efficient way to get the indexes of those

pixels falling within a particular window (lets call them low_val and

high_val) from a PCAShapeSignedDistanceFunction ?

Thanks,


Lucas


Lucas Lorenzo


University of Utah

Nora Eccles Harrison CardioVascular Research and Training Institute

Fellows Room

95 South 2000 East

Salt Lake City, UT 84112-5000


e-mail:  lucas at cvrti.utah.edu

telephone: 801-587-9536


_______________________________________________

Insight-users mailing list

Insight-users at itk.org

http://www.itk.org/mailman/listinfo/insight-users

</excerpt>_______________________________________________

Insight-users mailing list

Insight-users at itk.org

http://www.itk.org/mailman/listinfo/insight-users


</excerpt>Lucas Lorenzo


University of Utah

Nora Eccles Harrison CardioVascular Research and Training Institute

Fellows Room

95 South 2000 East

Salt Lake City, UT 84112-5000


e-mail:  lucas at cvrti.utah.edu

telephone: 801-587-9536


--Apple-Mail-1--539876014--