Slicer3 Rendering Pipeline

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Slicer3 Rendering Pipeline

• Study documents
• Raimundo Sierra

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Nomenclature
Datavolume
Slicer3 normal mode
Full screen mode
py
I1
y
py
I1
I2
I3
px
px
z
Normal mode, Px, Py typically 200x200 ? O(px
py) 40k pixels Full screen 1000x1000 1M
pixels Factor 25 leads to perceivable slowdown,
from 16ms/rendering to 200 ms
x
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Slicer 3 Rendering Pipeline
GUI, Programming
GUI Navigation
Image Processing
Data Volume
Image Processing
Image Processing
Rendering
Display
vtkSlicerSliceLayerLogic.h vtkSlicerSliceLogic.h
GPU
CPU
Painting?
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Image Processing Details vtkSlicerSliceLayerLogic
.h
Extract Alpha
Alpha logic
Append
Cast
Reslice Threshold
Append
Reslice
A
Thres-hold
Extract Lumi-nance
Map to colors
RGB
2D
3D
O(xyz)
O(px py)
SLOW!
standard VTK filters - 3D operations
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Image Processing DetailsExtended Reslice
New output ImageData BackgroundImageMask
Alpha logic
Cast
Append
Reslice
Thres-hold
A
RGB
Map to window level colors
Map to colors
2D
3D
faster - filter with additional source
O(xyz)
O(px py)
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Image Processing DetailsNext ExtractImage
Alpha logic
Cast
Append
Reslice
Thres-hold
A
RGB
Map to window level colors
Map to colors
only one iteration through data -
flexibility? - still O(px py)
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Slicer 3 Rendering Pipeline
GUI, Programming
GUI Navigation
Image Processing
Data Volume
Image Processing
Image Processing
Rendering
Display
vtkSlicerSliceLayerLogic.h vtkSlicerSliceLogic.h
GPU
CPU
Painting?
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Image Processing Details vtkSlicerSliceLogic.h
Foreground
Append
Blend
Background
Append
Labelmap
Append
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Slicer 3 Rendering Pipeline
GUI, Programming
GUI Navigation
Image Processing
Data Volume
Image Processing
Rendering
Display
Rendering
GPU
CPU
Painting?
10
Slicer 3 Rendering PipelineGPU Based rendering
Image Processing
Data Volume
Image Processing
Rendering
Display
GPU
CPU

1. Submit complete datavolume to the GPU
   (glTexture3D)
2. Extract slice by specifying plane with associated
   texture coordinates (glVertex, glTextureCoord)
3. Render textured plane in different rendering
   targets (slice windows 3D window

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Current Rendering Pipelinevs. GPU Based rendering

• Pros
• Speed Use of parallel rendering pipeline of GPU

• Cons
• Limited GPU memory in particular when volume
  consists of foreground, background, and labelmap
  datasets
• Implementation
• 3D texture support in VTK
• Large/significant changes in existing code