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How are the sample points selected? I get that they're weighted according to edge intensity, but what kind of distribution are you using in cases where there is no edge?

EDIT: I've read the code - it seems to be using random sampling. Still not entirely sure how a point can be placed at a place with absolutely no Sobel response - maybe it can't, which would make sense. My question arose after looking at: https://i.imgur.com/9YHOtQ0.png and then https://i.imgur.com/XRF7mz4.png. It looks like samples have been placed in regions with no response, but perhaps my eyes just can't see the edges.




This is an area that needs work, but basically there's the table of 'edge intensity' that gets multiplied by a constant baseChance variable for every pixel.

baseChance = 8 * samples / (width * height)

samples is the desired number of samples.

Again, this needs work. I'm pretty sure there's a way I can more accurately match the number of output samples to the desired number of samples.

Edit: And no, it can't produce a response if there's no edge (a value of zero). However, there's always some level of noise. This is true of the example you've shown - there's very light noise visible.


I see - thanks for the explanation!

Have you tried using Canny Edge detection rather than Sobel? It might help a bit with the noise. I've just attempted it, but can't seem to get Canny working under Mono (I've not got a windows machine at the moment).




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