[Insight-users] itkStreamingImageFilter with itkHessianSmoothed3DToVesselnessMeasureImageFilter

[Karthik Krishnan]

On Wed, Nov 5, 2008 at 4:14 AM, Dan Mueller <dan.muel at gmail.com> wrote:
> Hi Iván,
>
>> Could someone also test the performance?
>
> I put together a simple program (see below) to test the performance of
> DiscreteHessianGaussianImageFunction (the test image is in the ITK
> Testing\Data\Input folder). As you assumed the recursive approach is
> much faster:
>
> HessianTest HeadMRVolumeCompressed.mha
> Filter took 0.0792656 seconds
> Function took 17.0815 seconds
>
> Image Size = [48, 62, 42]
> Image Spacing = [4.0, 4.0, 4.0]
> Sigma = 1.0
> MaxKernelWidth = 32
> MaximumError = 0.01
> NormalizeAcrossScale = false
> UseImageSpacing = false
>
> Speed Factor = 17.08 / 0.079 = 216
>
> (Windows Vista SP1, Visual Studio 2005, Release build, Intel Core 2
> Duo 2GHz, 3 GB RAM)
>
> So to make the new function pay off (in terms of speed) it seems a
> user will have to restrict the computation to an image region ~1/250
> of the whole input image. For my use cases this is a certainty, but I
> can image for some (most?) this will not be the case.

Thanks a lot Dan. This information is very helpful. It would be great if you
could add it as a review to the paper:
  http://www.insight-journal.org/browse/publication/179

A factor of 250 is rather steep. I was hoping it'd be a x10 slowdown,
which would
work well for me. Having a function is very convenient since I can compute
the hessian on a masked image, which is what I need.

Ivan: Could you please tell us if you expected a factor of 250 slowdown ?

Thanks
--
karthik