[Insight-developers] GetPixel and SetPixel

[Lydia Ng]

Hi,

I am a newbie to this list, so please excuse me if
this question has been posted before.

I am under the impression that: 
1) the data in the Image<,> class is stored 
such that the column index is the fastest
varying then row, then slices etc..., and

2) the Index class is defined such that
index[0] = column; index[1] = row; index[3] = slice etc..

If these two observation are right, it seems that
there is an error in Image<,>::SetPixel() and
Image<,>::GetPixel(). 
In the code below shouldn't 
the for loop go from i = 0 to dimension -1 ?

Cheers,
Lydia

----------------------------------------------------

template<class TPixel, unsigned int VImageDimension>
void 
Image<TPixel, VImageDimension>
::SetPixel(const Index &ind, const TPixel& value)
{
  // FIXME: add bounds checking for the region/image
  unsigned long offset=0;
  unsigned long prod=1;

  const unsigned long *index = ind.GetIndex();
  
  const unsigned long *size = this->GetSize();
  unsigned int dimension = this->GetDimension();
  
  // data is arranged as [][][][slice][row][col]
  for (int i=dimension-1; i >= 0; i--)
    {
    offset += prod*index[i]; 
    prod *= size[i];
    }
  
  (*m_Data)[offset] = value;
}


----
Lydia Ng, Research Scientist
MathSoft, Inc.
1700 Westlake Ave N, Suite 500 
Seattle WA 98109  
lng at statsci.com
Tel: 206-283-8802 x308 
Fax: 206-283-6310