Re: Remove speckles in bilevel (bw) image

Hi,
Laurent S. schrieb:
> Free access means no payment, or does it mean that
> it is also for public, but for a (little) payment?


I suspect freeware with an appeal for contribution
would get optimal results. It's your program and your decision.

I dont ment my program, but the account to the math-papers.
But i think i get the point now. As said, my english is not the
best.


> Yes, it ["Least4"] should remove all 8way > connected Pixels with less
> then 4 counts. Except the 2 border > pixels, that are not processed.

Try it on "gutter.tiff". Bugs?

You can test it with:
http://freenet-homepage.de/JDierks/tmp/gen3pixel.bmp

These patterns are all removed.
To keep all 4 and higher count blobs, i have to add some
code, as i mentioned before.


I have encountered remarks that weighted median filtering is only good for small blobs.
Worth exploring.

The (weighted) median cannot differ between good
and bad pixel, if you want to erase larger blobs, then it
has also an effect on larger parts of the letters, like
edge rounding.
If you dont want to change the letters at all, median
does not work.

PS. A switch in your program requesting
white speckle elimination would be very useful
in prectice.

Should be makeable.

Regards, Jens
.

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