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ee.Image.spectralGradientStay organized with collectionsSave and categorize content based on your preferences.
Computes the spectral gradient over all bands of an image (or the first band if the image is Array typed) by computing the per-pixel difference between the spectral erosion and dilation with a given structuring kernel and distance metric. See: Plaza, Antonio, et al. 'Spatial/spectral endmember extraction by multidimensional morphological operations.' IEEE transactions on geoscience and remote sensing 40.9 (2002): 2025-2041.
Usage
Returns
Image.spectralGradient(metric,kernel,useCentroid)
Image
Argument
Type
Details
this:image
Image
The input image.
metric
String, default: "sam"
The spectral distance metric to use. One of 'sam' (spectral angle mapper), 'sid' (spectral information divergence), 'sed' (squared Euclidean distance), or 'emd' (earth movers distance).
kernel
Kernel, default: null
Connectedness kernel. Defaults to a square of radius 1 (8-way connected).
useCentroid
Boolean, default: false
If true, distances are computed from the mean of all pixels under the kernel instead of the kernel's center pixel.
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