[vtk-developers] imaging pipeline bug

[dean.inglis at camris.ca]

Hi,

a while back, I had developed a pipeline
for polygonal region of interest analysis
of 2D images using:

vtkImageData -> vtkImageTracerWidget
   |                 |
   |            vtkPolyData
   |                 |
   |            vtkLinearExtrusionFilter 
   |                 |
   |            vtkPolyDataToImageStencil 
   |             |              |
   vtkImageStencil              |  
   |                            |
vtkImageMapToWindowLevelColors  | 
   |                            | 
vtkImageActor         vtkImageAccumulate (rev. 1.51)

With recent revisions (after conversion to the new pipeline), the pipeline 
crashes in both .cxx and .tcl test codes upon requesting image stats 
from vtkImageAccumulate (e.g. GetMean, etc.).

Enclosed is a simplified (no vtkImageTracerWidget required) .tcl 
script that demonstrates the problem with the latest vtk cvs checkout 
(a .cxx version is also available).  Not being overly familiar with the mechanics
of the (still evolving?) new pipeline is making the debug of this difficult.
Any help would be greatly appreciated as I would like to prepare to adapt 
my production builds and local classes to include the new vtk pipeline code.

thanks,
dean

/////////////////////////////////////////////////////////////////////////////////////////////////////
package require vtk
package require vtkinteraction

  vtkVolume16Reader v16
  v16 SetDataDimensions 64 64
  v16 SetDataByteOrderToLittleEndian
  v16 SetImageRange 1 93
  v16 SetDataSpacing 3.2 3.2 1.5
  v16 SetFilePrefix "$VTK_DATA_ROOT/Data/headsq/quarter"
  v16 ReleaseDataFlagOn
  v16 SetDataMask 0x7fff

  vtkExtractVOI extract
  extract SetVOI 31 31 0 63 0 92
  extract SetSampleRate 1 1 1
  extract SetInput [v16 GetOutput]
  extract ReleaseDataFlagOff
  extract Update

  set range [[extract GetOutput] GetScalarRange]
  set min [lindex $range 0]
  set max [lindex $range 1]
  set diff [expr $max - $min]
  set avg [expr 0.5*($max + $min)]
  set bounds [[extract GetOutput] GetBounds]

  vtkPoints points
  points SetNumberOfPoints 5

  set x [lindex $bounds 0]
  set y0 [expr 0.25*[lindex $bounds 3]]
  set y1 [expr 0.75*[lindex $bounds 3]]
  set z0 [expr 0.25*[lindex $bounds 5]]
  set z1 [expr 0.75*[lindex $bounds 5]]

  points SetPoint 0 $x $y0 $z0
  points SetPoint 1 $x $y1 $z0
  points SetPoint 2 $x $y1 $z1
  points SetPoint 3 $x $y0 $z1
  points SetPoint 4 $x $y0 $z0

  vtkCellArray cells
  cells InsertNextCell 5

  for {set i 0} {$i < 5} {incr i} {
    cells InsertCellPoint $i
    }

  vtkPolyData region
  region SetPoints points
  region SetLines cells

  vtkPolyDataMapper regionMapper
  regionMapper SetInput region

  vtkActor regionActor
  regionActor SetMapper regionMapper
  [regionActor GetProperty ] SetColor 1 0 0

  vtkLinearExtrusionFilter extrude
  extrude SetScaleFactor 1
  extrude SetExtrusionTypeToNormalExtrusion
  extrude SetVector 1 0 0
  extrude SetInput region

  vtkPolyDataToImageStencil dataToStencil
  dataToStencil SetInput [extrude GetOutput]

  vtkImageStencil stencil
  stencil SetInput [extract GetOutput]
  stencil SetStencil [dataToStencil GetOutput]
  stencil ReverseStencilOff
  stencil SetBackgroundValue $min

  vtkImageMapToWindowLevelColors imageMapper
  imageMapper SetOutputFormatToLuminance
  imageMapper SetInput [stencil GetOutput]
  imageMapper SetLevel $avg
  imageMapper SetWindow $diff

  vtkImageActor imageActor
  imageActor SetInput [imageMapper GetOutput]
  imageActor SetDisplayExtent 31 31 0 63 0 92
  imageActor InterpolateOff

  vtkImageAccumulate accum
  accum SetInput [extract GetOutput]
  accum ReverseStencilOff
  accum SetStencil [stencil GetStencil]
  accum SetComponentSpacing 1 0 0
  accum SetComponentExtent 0 $diff 0 0 0 0
  accum SetComponentOrigin $min 0 0
  accum ReleaseDataFlagOff
  accum Update

  set aN [accum GetVoxelCount]
  set amin [accum GetMin]
  set amax [accum GetMax]
  set amean [accum GetMean]
  set astd  [accum GetStandardDeviation]

  set atext {}
  append atext "N: "
  append atext [string toupper $aN]
  append atext ", \["
  append atext [string toupper [lindex $amin 0] ]
  append atext " -> "
  append atext [string toupper [lindex $amax 0] ]
  append atext "\] "
  append atext [string toupper [lindex $amean 0] ]
  append atext " +- "
  append atext [string toupper [lindex $astd 0] ]
  append atext " HU"

  vtkTextActor textActor
  textActor ScaledTextOff
  textActor SetInput $atext
  [textActor GetPositionCoordinate] SetCoordinateSystemToNormalizedDisplay
  [textActor GetPositionCoordinate] SetValue 0.01 0.99

  set tprop [textActor GetTextProperty]
  $tprop SetFontSize 16
  $tprop SetFontFamilyToArial
  $tprop BoldOff
  $tprop ItalicOff
  $tprop ShadowOff
  $tprop SetLineSpacing 0.9
  $tprop SetJustificationToLeft
  $tprop SetVerticalJustificationToTop
  $tprop SetColor 1 1 0

  vtkRenderer ren
  ren SetBackground 0.4 0.4 0.5

  vtkRenderWindow renWin
  renWin AddRenderer ren
  renWin SetSize 400 400

  vtkInteractorStyleImage interactor

  vtkRenderWindowInteractor iren
  iren SetInteractorStyle interactor
  iren SetRenderWindow renWin

  ren AddProp imageActor
  ren AddProp regionActor
  ren AddProp textActor

  iren AddObserver UserEvent {wm deiconify .vtkInteract}
  renWin Render

  set cam [ren GetActiveCamera]
  $cam SetViewUp 0 1 0
  $cam Azimuth 270
  $cam Roll 270
  $cam Dolly 1.7
  ren ResetCameraClippingRange

  renWin Render

# Prevent the tk window from showing up then start the event loop.
  wm withdraw .