[vtkusers] Problem with allocating memory for huge vtkImage and memory-fragmentation ?

[Ashika Umanga Umagiliya]

Greetings all,

In our application we need to load large volumedata (2000x2000x1000  - 8
bpp).
In the "Vtk Users Guide" I came across following  example to create
vtkImageData.

vtkImageData *id=vtkImageData::New();
id->SetDimentions(nx,ny,nz);
id->SetScalarTypeToUnsignedChar();
id->SetNumberOfScalarComponents(1);
id->AllocateScalars();

//Fill in scalar values
unsigned char *ptr=(unsigned char*)id->GetScalarPointer();
for(int i=0;i<nx*ny*nx;i++){
 *ptr++=i;
}

Looking at the way assigning values and the method GetScalarPointer(); , it
seems that one block of memory is allocated for entire (nx*ny*nz) pixels.
If it allocate entire memory block,would it cause problem with
memory-fragmentation ?
Or is there any other memory allocation schema ?

Thanks in advance.
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