[Insight-users] get the maximum pixel value using GetPixel() for 3D image

[robert tamburo]

GetPixel() belongs to itkImage, not the reader. Try
reader->GetOutput()->GetPixel(index).

Two other things: 1) You may want to consider using an ImageRegionIterator
instead of for loops, and 2) You can use the MinimumMaximumImageCalculator
to get the maximum intensity in an image.

There are examples on how to use each class at
http://www.itk.org/Wiki/ITK/Examples

<http://www.itk.org/Wiki/ITK/Examples>

On Tue, Jun 7, 2011 at 8:36 AM, john smith <mkitkinsightuser at gmail.com>wrote:

> Hello,
>
> I am trying to find the maximum pixel value of a 3D  image, and I am using
> the GetPixel method with 3 loops.I want to load my image from a file so I
> created a reader pointer.Does this pointer include the raw data of my image?
> I have created the following code but I get an error: GetPixel() method is
> not a member of reader. Could somebody tell me what I am doing wrong? How I
> could find the maximum pixel value of a loaded image with the method of
> GetPixel()?
>
> Thanks
>
>   typedef short               InputPixelType;
>   const   unsigned int        Dimension = 3;
>
>   typedef itk::Image< InputPixelType,  Dimension >    InputImageType;
>   typedef itk::ImageFileReader< InputImageType  >  ReaderType;
>
>
>   ReaderType::Pointer reader = ReaderType::New();
>
>      reader->SetFileName( fileName.toStdString()  );
>      reader->Update();
>
>        InputImageType::RegionType inputRegion =
>            reader->GetOutput()->GetLargestPossibleRegion();
>
>   InputImageType::SizeType size = inputRegion.GetSize();
>
>   // get the size of the hole 3D image
>   size_x = size[0];
>   size_y = size[1];
>   size_z = size[2];
>
>    InputImageType::IndexType start = inputRegion.GetIndex();
>   start[0] =   0;  // first index on X
>   start[1] =   0;  // first index on Y
>   start[2] =   0;  // first index on Z
>
>  int i,j,k;
>  int max_value=0;
>   for ( i=0;i<size_x;i++) {
>       for ( j=0;i<size_y;j++){
>           for ( k=0;i<size_z;k++){
>
>               InputImageType::IndexType pixelIndex;
>                 pixelIndex[0] = i; // x position
>                 pixelIndex[1] = j; // y position
>                 pixelIndex[2] = k; // z position
>
>                 InputImageType::PixelType pixelValue = reader->GetPixel(
> pixelIndex );
>
>                 if(pixelValue>max_value){max_value=pixelValue;}
>
>           }
>       }
>   }
>
> _____________________________________
> Powered by www.kitware.com
>
> Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
>
> Kitware offers ITK Training Courses, for more information visit:
> http://www.kitware.com/products/protraining.html
>
> Please keep messages on-topic and check the ITK FAQ at:
> http://www.itk.org/Wiki/ITK_FAQ
>
> Follow this link to subscribe/unsubscribe:
> http://www.itk.org/mailman/listinfo/insight-users
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.itk.org/pipermail/insight-users/attachments/20110607/44b8d001/attachment.htm>