[SciPy-User] Arbitrary max-intensity projection

[David Baddeley]

This gets even easier if you use mayavi

from enthought.mayavi import mlab
f = mlab.figure()
v = mlab.pipeline.volume(mlab.pipeline.scalar_field(data.astype('uint8')))

you can then use the pipeline tool to (graphically) change the "Volume mapper type" to "RayCastMapper" and the "Ray cast function type" to "RayCastMIPFunction". (There's probably also a programatic way to do this)

cheers,
David

--- On Fri, 9/9/11, Christoph Gohlke <cgohlke at uci.edu> wrote:

> From: Christoph Gohlke <cgohlke at uci.edu>
> Subject: Re: [SciPy-User] Arbitrary max-intensity projection
> To: scipy-user at scipy.org
> Received: Friday, 9 September, 2011, 11:13 AM
> 
> 
> On 9/8/2011 3:29 PM, Chris Weisiger wrote:
> > I have a 3D volume of image data. I want to do a
> max-intensity
> > projection of that data along an arbitrary axis (that
> is, not
> > necessarily orthogonal). For example, projecting along
> the axis<1, 0,
> > .5>  would generate results like looking at
> the data a bit from above.
> > Basically we're faking 3D views of our data.
> >
> > OpenGL 3D textures don't work due to the size of the
> image data in
> > question (e.g. 512x512x60). Someone suggested
> reimplementing
> > Amanatides&  Woo, which is a fairly simple
> voxel raytracer. However,
> > that doesn't mean it's trivial to implement, and I'd
> rather not
> > reinvent and optimize the wheel if at all possible.
> Does anyone have
> > any suggestions for known solutions to this problem?
> >
> > -Chris
> 
> 
> Did you try VTK's vtkVolumeRayCastMIPFunction function as
> suggested before?
> 
> <http://www.vtk.org/doc/release/5.8/html/a02285.html>
> <http://www.uppmax.uu.se/Members/andersh/vtk-with-python/volume-rendering/Volume.py/view?searchterm=None>
> 
> 
> OpenGL 3D textures should work if you successively render
> sub-volumes in 
> the correct position and order. MIP can also be implemented
> with 
> object-aligned 2D textures.
> 
> Christoph
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