How to capture a screenshot and turn it into a numpy array with python code?

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Hi @user4 -

Yes, you are very close - the example I pointed to was for getting the compressed png data as an array (e.g. the data in a .png file). Instead you need to get the array from the vtkImageData that comes from the vtkWindowToImageFilter.

Here’s the snippet:

view = slicer.app.layoutManager().threeDWidget(0).threeDView()
renderWindow = view.renderWindow()
renderWindow.SetAlphaBitPlanes(1)
wti = vtk.vtkWindowToImageFilter()
wti.SetInputBufferTypeToRGBA()
wti.SetInput(renderWindow)
wti.Update()
image_array = vtk.util.numpy_support.vtk_to_numpy(vtk_data.GetPointData().GetScalars())
image_array = image_array.reshape((view.height, view.width, 4))

You may need to swap width and height - I didn’t check that for sure.

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