On Thu, May 26, 2011 at 9:52 PM, Bruce Walker <[email protected]> wrote: > You're welcome, Paul. > > This was a fun little project. I'm glad Dave shared this problem with us. > > -bmw Oh I have a LOT more,:-)
But i do thank you all for the help and tips. Jackie is pleased with what i did and what Bruce did. We try and get together at least once a year. If we do i will take John's advice and try to photograph the picture and see how that works Dave > > > On 11-05-26 8:02 PM, Paul Stenquist wrote: >> >> Good to know. Thanks for this. >> Paul >> On May 26, 2011, at 7:50 PM, Bruce Walker wrote: >> >>> On 11-05-26 6:08 PM, John Sessoms wrote: >>>> >>>> From: John Sessoms >>>>> >>>>> Ok, so I had a go at seeing what I could do at restoring the image >>>>> using >>>>> the tools Bruce linked to. >>>> >>>> Never mind. I took another look at the corrected image Bruce had posted >>>> and took my attempt down right away. >>>> >>>> Got to install imagemagick& see if I can figure out how to use it. >>>> >>>> The Photoshop plug-in doesn't seem to work as well as imagemagick. >>> >>> John, I believe they both use the same FFT engine, the opensource project >>> FFTW.org, so I'd expect that they should work about the same, given the same >>> inputs. >>> >>> What did your spectral mask look like? You may not have removed enough >>> points. I iterated on that image a couple of times, removing more spectrum >>> each time before I was satisfied that I'd suppressed enough of the >>> original's vertical lines. >>> >>> Here's the image I got for the frequency space in Dave's (leveled and >>> cropped) original: >>> http://dl.dropbox.com/u/2254722/picture0001_spectrum.png >>> >>> And here's the mask I ended up with, created in Photoshop by painting >>> black onto a white layer with a 10% hard brush: >>> http://dl.dropbox.com/u/2254722/picture0001_spectrum_mask2.png >>> >>> You don't want to allow any hard edges in the mask as that will create >>> new artifacts (especially ringing near any edges), so you must either use a >>> soft-edged brush or apply Gaussian blur to your mask before applying it. >>> >>> When creating the mask I looked for anything in the frequency-space image >>> that seemed regular and symmetrical. Normally an image like that (especially >>> such a soft one) should have a pretty uniform and random looking spectral >>> distribution, so any dense white clusters or stars are suspect. As you can >>> see I was fairly sloppy with my hand drawing of the mask, but it doesn't >>> seem to matter all that much, so you can fairly safely err on the generous >>> side. >>> >>> A quirk of the FFTFILTER script is it expects the input image and the >>> mask image to be the same dimensions, so I expanded the canvas of the >>> original image (to 2092x2092) making it square, with black bars above and >>> below. >>> http://dl.dropbox.com/u/2254722/picture0001-2092.png >>> >>> When you install ImageMagick on your computer, make sure that the FFTW >>> library is already installed for it to find, or it won't be able to do any >>> FFT operations. If you get error messages when trying to run the script, >>> Googling on those messages will get you lots of help on the proper >>> configuration of this stuff. >>> >>> Good luck! >>> >>> -bmw >>> >>> -- >>> PDML Pentax-Discuss Mail List >>> [email protected] >>> http://pdml.net/mailman/listinfo/pdml_pdml.net >>> to UNSUBSCRIBE from the PDML, please visit the link directly above and >>> follow the directions. >> > > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- Documenting Life in Rural Ontario. www.caughtinmotion.com http://brooksinthecountry.blogspot.com/ York Region, Ontario, Canada -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
