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contrast: local contrast based on guided filter

increase or decrease local contrast in an image. this utilises the guided filter to extract a coarse image.

connectors

• input
• output

parameters

• radius the radius in effect for the guided filter
• edges the edge threshold parameter for the guided filter
• detail the amount of detail enhancement (as for unsharp masking)
• thrs the threshold used for detail enhancement (as for unsharp masking)

use cases

use this module at the default settings to enhance texture in the image, while leaving edges as they are.

to emphasise edges instead, while leaving texture as it is, you would increase the edges parameter to say 0.5 and also up the thrs parameter to say 0.003 to make the algorithm ignore texture detail.

use sparingly!