Fw: [Insight-users] Converting Image Data to Vector type

Mon, 5 Aug 2002 16:31:12 +0200

Thanks Jisung and Luis,

I will study both options.Apparently, Jisung's solution is easier. I'll
report on what I do and if It works fine.

Thanks again,
Samuel

----- Original Message -----
From: "Jisung Kim" <bahrahm@yahoo.com>
To: "Samuel_Rodrguez_Bescos" <srodrigu@gbt.tfo.upm.es>
Cc: "Insight-Users" <insight-users@public.kitware.com>
Sent: Monday, August 05, 2002 4:02 PM
Subject: Re: Fw: [Insight-users] Converting Image Data to Vector type

> Hello.
>
> I don't think the PNG IO supports reading vector pixel
> type images. But, for the first problem, casting
> scalar  image to vector image can be done using the
> itkScalarToArrayCastImageFilter. You can cast any
> built-in scalar type (int ,long, float, ...) to
> itk::FixedArray or its subclasses (e.g. itk::Point,
> itk::Vector, ...).
>
> Thank you,
>
> Jisung Kim.
>
> --- Samuel_Rodr&#65533;guez_Bescos
> <srodrigu@gbt.tfo.upm.es> wrote:
> > Thanks Luis for your help.
> >
> >  Your second reply solves my problem. But My first
> > question in not the same
> > that you think. I have a grey scale images and I
> > want to use the gibbs
> > segmentation filter. This filter need  a mask of the
> > estimation of my object
> > and I want to use the gaussian classifier. I noticed
> > that this filter need
> > the input in vector format. furthermore I want to
> > read my image in .PNG
> > format and I think that It not  posible to read a
> > gray-scale image in .PNG
> > format with pixels like  vectors of one dimension.
> > Maybe I can't explain you
> > enough clearly, I'm sorry for that but my English is
> > not so good.
> >
> > Thank for your help. It very useful for me,
> >
> > Samuel
> >
> > ----- Original Message -----
> > From: "Luis Ibanez" <luis.ibanez@kitware.com>
> > To: <srodrigu@gbt.tfo.upm.es>
> > Cc: <insight-users@public.kitware.com>
> > Sent: Friday, August 02, 2002 8:53 PM
> > Subject: Re: Fw: [Insight-users] Converting Image
> > Data to Vector type
> >
> >
> > >
> > > Hi Samuel,
> > >
> > >
> > >  From your first answer I understand that you have
> > a set
> > > of N .png files each one containing a gray-scale
> > image
> > > and you want to load them into a itkImage with a
> > > ND vector as pixeltype. Is that right ?
> > >
> > > Here are two options:
> > >
> > > 1) use Image Adaptors.
> > >
> > > 2) use a two stage process : load the N image
> > >     and then copy their content to a Vector image.
> > >
> > > Option (1) will probably work better with the
> > pipeline
> > > update mechanism.
> > >
> > > Please take a look at the class
> > >
> >
>
http://www.itk.org/Insight/Doxygen/html/classitk_1_1NthElementImageAdaptor.h
> > tml
> > >
> > > It can be found at:
> > >
> > > Insight/Code/Common/itkNthElementImageAdaptor.h
> > >
> > > An example of the use of adaptors can be seen at:
> > >
> > >
> >
> Insight/Testing/Code/BasicFilters/itkImageAdaptorNthElementTest.cxx
> > >
> > > --------
> > >
> > > About the second answer:
> > >
> > > If you already have a labeled image and just want
> > to reduce this
> > > one to a 1,0 images, the
> > BinaryThresholdImageFilter:
> > >
> >
>
http://www.itk.org/Insight/Doxygen/html/classitk_1_1BinaryThresholdImageFilt
> > er.html
> > >
> > > (as you pointed out) should solve the problem.
> > >
> > > This filter expect you to define lower and upper
> > values
> > > for a gray-level range. Then the image is filtered
> > and all
> > > the pixels with values outside this range will be
> > mapped to
> > > an "OutsideValue" (provided by the user) while the
> > pixels
> > > with values inside the range will be mapped to an
> > "InsideValue".
> > >
> > > Something like the following code should do it:
> > >
> > >    binaryFitler.SetInput(
> > myLabelFilter.GetOutput() );
> > >    binaryFilter.SetOutsideValue( 0 );
> > >    binaryFilter.SetInsideValue( 1 );
> > >    binaryFilter.SetUpperThreshold(myLabel+1);
> > >    binaryFilter.SetLowerThreshold(myLabel-1);
> > >
> > >    binaryFitler.Update();
> > >
> > >
> > > assuming that myLabelFilter is the one that label
> > your image
> > > and the "myLabel" value is the one you are
> > interested on.
> > >
> > >
> > > Please let us know if that helps.
> > >
> > > Thanks,
> > >
> > >    Luis
> > >
> > >
> > >
> >
> =====================================================
> > > >>Hello Luis,
> > > >>
> > > >>The anwers for your questions,
> > > >>
> > > >>1) I want to read a .png image file into a
> > vector image.The problem is
> > > >>
> > > > that
> > > >
> > > >>I'm using the Gibbs filter with a Gaussian
> > estimator and the last one
> > > >>
> > > > needs
> > > >
> > > >>to have the input as vector image. I'm using
> > grey-scales images.
> > > >>
> > > >>2) For the second question: I'm using the
> > watershed class to segment an
> > > >>image of a slice of the human abdomen (the liver
> > zone of the human
> > body).
> > > >>The output is an image with labeled  pixels. I
> > want to create a new
> > image
> > > >>selecting the pixels that have the same label
> > and the get one object.I
> > > >>
> > > > think
> > > >
> > > >>I can do that with BinaryThresholdImageFunction
> > class. Is it possible?
> > > >>
> > > >>Thanks for your reply,
> > > >>
> > > >>Samuel
> > > >>
> > >
> >
> > _______________________________________________
> > Insight-users mailing list
> > Insight-users@public.kitware.com
> >
> http://public.kitware.com/mailman/listinfo/insight-users
>
>
> =====
> Jisung Kim
> bahrahm@yahoo.com
> 106 Mason Farm Rd.
> 129 Radiology Research Lab., CB# 7515
> Univ. of North Carolina at Chapel Hill
> Chapel Hill, NC 27599-7515
>
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