Add or maintain window level preset

Support
1

I am trying to create a window/level preset so it pops down on right-click of the slice panes, or make a previous manual preset “sticky”, as described here. I would prefer to do the sticky option, because the person for whom I am implementing this is interrogating a lot of volumes back-to-back. However, I’m not really sure where to start with this. I’ve made python modules before, but this seems like I would need to write something in the C++ code for the application, perhaps here. Are there any tips for how I should go about implementing such a feature? Thanks so much for your support!

2

When Slicer loads an image, it uses the window/level that is stored in the image file. If the image is loaded from a research format, which does not store display settings then the window/level is automatically computed from the image content.

You can add or modify window/level presets in this file:

<SlicerHome>\share\Slicer-5.0\qt-loadable-modules\Volumes\VolumeDisplayPresets.json

You can copy-paste these few lines of of Python code into the Python console if you want to apply a custom window/level preset when a node is loaded:

@vtk.calldata_type(vtk.VTK_OBJECT)
def onNodeAdded(caller, event, node):
    if isinstance(node, slicer.vtkMRMLScalarVolumeDisplayNode):
        # Call using a timer instead of calling it directly to allow the volume loading to fully complete.
        qt.QTimer.singleShot(0, lambda: setCustomWindowLevel(node))

def setCustomWindowLevel(displayNode):
    displayNode.SetAutoWindowLevel(False)
    displayNode.SetWindowLevel(16, 128)

slicer.mrmlScene.AddObserver(slicer.vtkMRMLScene.NodeAddedEvent, onNodeAdded)
1 Like
3

Thank you very much!