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Tricky FFT

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  • Tricky FFT

    Hello everyone,
    I'm having some difficulty with an image from which I wish to remove texture. I've tried ImageJ, Image Analyzer, and the FFT PS plugin, and the result is the same with all three. It processes the image fine, but when I zoom in on the FFT (the cross and stars thing) there are no stars other than the central star to paint out. I've painted over any tiny thing I can squint and make my eyes think might be a star, but it really doesn't change the image at all.
    I've tried sharpening the image before FFT which didn't help, and I tried just using Noiseware, which sort of kind of worked but generally I don't like the results that way, it always seems to soften the image a little to much for me. I usually really like how FFT removes the texture and keeps detail. Anyway, any help would be greatly appreciated!

    Thank you!
    (When I reduce the image size to upload and then zoom back on it, I don't see the texture as well, but it is there...the paper is almost like a watercolor paper, but perhaps not as intense.)
    Attached Files

  • #2
    Re: Tricky FFT

    Why don't you post a 100% cropped view instead of a reduced resolution full view so we can see the texture. Just a thought.


    • #3
      Re: Tricky FFT

      Yep, a cropped version showing the pattern would be better.

      Or maybe upload it to if you are comfortable giving away a full resolution, higher quality, JPEG?
      Or possibly share a LZW-compressed TIFF-file using dropbox, filedropper, or similar? Could be useful on tricky jobs where JPEG artefacts might interfere.


      • #4
        Re: Tricky FFT

        Thank you Chain and John. I'll try dropbox, but as of now I've never used it so it will take some time. Can I use flickr?
        As for uploading a crop, I'd love to but still can't figure out how to get a small enough file without having to downrez. Any information on that would be very helpful to me.
        Thank you!


        • #5
          Re: Tricky FFT

          Testing, testing. Just seeing if this is going to work...
          I think it will work, please let me know if this is good enough or if I should just upload the whole thing...
          Thank you again for all your help!


          • #6
            Re: Tricky FFT

            The Dropbox file shows the texture quite nicely. Unfortunately, FFT processing won't work on it because the texture is irregular. A fast Fourier transform relies on repeating patterns to do its thing.


            • #7
              Re: Tricky FFT

              Thank you, Lurch, for your reply. Yeah, I wondered as much. As I said, it's kind of like a watercolor paper, it feels heavy like a card stock, not like typical photo paper.
              Any thoughts about how to smooth it out without loosing too much detail? The thought of going through by hand just makes me hurt, so I'd probably just leave it in there.

              I've enjoyed using the FFT processing to get rid of textures, but previously I just decided that that texture was part of the original photo and it was ok to see it a little. Sometimes it gives the sensation of sharpness, like seeing the grain in film. And sometimes when I print the final version out and view it at a reasonable distance I don't really notice it as I do when I'm pixel peeping. And by reasonable distance I mean some distance where my nose isn't touching the print.
              Thank you


              • #8
                Re: Tricky FFT

                I'd say a little "Filter"-"Noise"-"Dust & Scratches" with a radius of 12 and a threshold of 5 masked in where needed should do the trick or at least give you a nice starting point :-).


                • #9
                  Re: Tricky FFT

                  You could get a start with a duplicate layer set to darken then offset until most of the texture is neutralized.

                  Check for an example HERE



                  • #10
                    Re: Tricky FFT

                    I tried two adjustments, one with Jonas' suggestion of Dust and Scratches filter with a radius of 12, but a threshold of 3, the 2nd with a Gaussian blur with a radius of 2:
                    ridTextr by Tori803, on Flickr


                    • #11
                      Re: Tricky FFT

                      My try Painter 12.
                      Attached Files


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