8.128. Robust Automatic Threshold

Group (Subgroup)

DREAM3D Review (Threshold)

Description

This Filter automatically computes a threshold value for a scalar Attribute Array based on the array’s gradient magnitude, producing a boolean array that is false where the input array is less than the threshold value and true otherwise. The threshold value is computed using the following equation:

$[ T = um_{i = 1}^{n} rac{a_{i} g_{i}}{g_{i}} ]$

where \f$ a \f$ is the input array, \f$ g \f$ is the gradient magnitude array, \f$ n \f$ is the length of the input array, and \f$ T \f$ is the computed threshold value. Computing a threshold in this manner will generally partition the input array where its gradient is highest. Gradients may be computed using the Find Derivatives Filter. The gradient magnitude may then be found by computing the 2-norm of the gradient.

Input Parameter(s)

Parameter Name	Parameter Type	Parameter Notes	Description
Input Array	Array Selection	Allowed Types: int8, uint8, int16, uint16, int32, uint32, int64, uint64, float32, float64 Comp. Shape: 1	DataArray to Threshold
Gradient Magnitude Data	Array Selection	Allowed Types: float32 Comp. Shape: 1	The complete path to the Array specifying the gradient magnitude of the Input Array
Mask	DataObjectName		Created mask based on Input Array and Gradient Magnitude

Example Pipelines

License & Copyright

Please see the description file distributed with this plugin.

DREAM3D-NX Help

If you need help, need to file a bug report or want to request a new feature, please head over to the DREAM3DNX-Issues GitHub site where the community of DREAM3D-NX users can help answer your questions.