11.63. ITK Regional Minima Image Filter

Produces a binary image marking the regional minima of the input image.

Group (Subgroup)

ITKMathematicalMorphology (MathematicalMorphology)

Description

A regional minimum is a connected flat zone of pixels that all share the same value and whose every neighboring pixel has a strictly higher value (a local “valley” that is darker than everything immediately surrounding it). This filter labels those pixels in the output and labels everything else as background, producing a binary image. Use it to detect dark spots, basins, or seed points for later segmentation.

If the input image is constant (completely flat), the entire image can be treated either as a single regional minimum or as background; the Flat Is Minima option selects which behavior to use.

Parameter Guidance

  • Flat Is Minima: When on (default), a completely flat input image is reported as a regional minimum; when off, a flat image produces an all-background result.

  • Fully Connected: Controls pixel connectivity. When off (default, “face connected”), only face-adjacent neighbors are considered (connectivity 4 in 2D, 6 in 3D); when on, diagonal neighbors are also included (connectivity 8 in 2D, 26 in 3D). Turning it on tends to merge nearby minima into a single connected region.

  • Background Value / Foreground Value: These are the output binary labels written for non-minima and minima pixels respectively. They are not intensity thresholds applied to the input.

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

Background Value

Scalar Value

Float64

Set/Get the value used as ‘background’ in the output image. Defaults to NumericTraits::NonpositiveMin() .

Foreground Value

Scalar Value

Float64

Set/Get the value in the output image to consider as ‘foreground’. Defaults to maximum value of PixelType.

Fully Connected

Bool

Set/Get whether the connected components are defined strictly by face connectivity or by face+edge+vertex connectivity. Default is FullyConnectedOff. For objects that are 1 pixel wide, use FullyConnectedOn.

Flat Is Minima

Bool

Set/Get whether a flat image must be considered as a minima or not. Defaults to true.

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

DREAM3D-NX Help

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