11.45. ITK Laplacian Recursive Gaussian Image Filter
Computes the Laplacian of Gaussian (LoG) of an image.
Group (Subgroup)
ITKImageFeature (ImageFeature)
Description
The Laplacian of Gaussian (LoG) first smooths the image with a Gaussian of a chosen width and then takes its second spatial derivative (the Laplacian). It is a classic blob and edge detector: it responds strongly to features whose size matches the Gaussian width, and the zero crossings of its output mark edge locations. A common workflow is to run this filter and then locate those edges with ITK Zero Crossing Image Filter. This implementation uses ITK’s recursive Gaussian filters, so the cost does not grow with the smoothing width.
Parameter Guidance
Sigma: Standard deviation of the Gaussian, measured in the units of the image spacing (e.g. micrometers, not pixels). Larger Sigma smooths more and tunes the filter to larger blobs/coarser edges.
Normalize Across Scale: Selects the normalization factor applied to the Gaussian. Leave off (default) for standard LoG output; turn on when comparing responses computed at different Sigma values (scale-space analysis) so that magnitudes remain comparable across scales.
Required Input Sources
Operates on any scalar image — typically from Read Image, Read Images [3D Stack], or a prior ITK image filter.
Input Parameter(s)
Parameter Name |
Parameter Type |
Parameter Notes |
Description |
|---|---|---|---|
Sigma |
Scalar Value |
Float64 |
Set/Get Sigma value. Sigma is measured in the units of image spacing. |
Normalize Across Scale |
Bool |
Define which normalization factor will be used for the Gaussian. See RecursiveGaussianImageFilter::SetNormalizeAcrossScale |
Input Cell Data
Parameter Name |
Parameter Type |
Parameter Notes |
Description |
|---|---|---|---|
Image Geometry |
Geometry Selection |
Image |
Select the Image Geometry Group from the DataStructure. |
Input Cell Data |
Array Selection |
Allowed Types: int8, uint8, int16, uint16, int32, uint32, int64, uint64, float32, float64 |
The image data that will be processed by this filter. |
Output Cell Data
Parameter Name |
Parameter Type |
Parameter Notes |
Description |
|---|---|---|---|
Output Image Data Array |
DataObjectName |
The result of the processing will be stored in this Data Array. |
Example Pipelines
License & Copyright
Please see the description file distributed with this Plugin.
DREAM3D-NX Help
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