Removing periodic noise from an image

tsiozos · Post by **tsiozos** » Wed Aug 13, 2008 5:35 pm

I have the following scanned photo and I want to remove the periodic pattern saving as much as possible of the detail. Any suggestions?

I've already tried Median Filter and moire pattern and digital noise reduction filters but they give a staircase-like pattern in the hair edges and elsewhere.

sjj1805 · Post by **sjj1805** » Wed Aug 13, 2008 5:47 pm

Prevention is better than cure.
Check your scanner settings for a "Descreen" setting.
Here is an article on the subject.

If you still have the original image you might be better scanning again with the appropriate settings.

tsiozos · Post by **tsiozos** » Wed Aug 13, 2008 7:51 pm

Thanks Steve.
Although my scanner doesn't have a descreen option, scanning at double the res, then a median filter then downsampling reduced the noise to acceptable levels.