MaskTools/HysteresyMask
HysteresyMask (clip mask_clip1, clip mask_clip2)
Plugin: MaskTools
This filter creates a mask from two masks. Theoritically, the first mask should be inside the second one, but it can work if it isn't true (though results will be less interesting). The principle of the filter is to enlarge the parts that belongs to both masks, inside the second mask.
This algorithm is interesting because it allows for example to obtain an edge mask with all the interesting edges, but without the noise. You build two edge masks, one with a lot of edges and noise, the other one with a few edges and almost no noise. Then, you use this filter, and you should obtain the edges, without the noise, because the noise wasn't there in the second mask.
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