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Open Source Image De-Noising
GREYCstoration is an open-source tool able to de-noise, inpaint, or resize 2D color images. This is a command-line program developed by the IMAGE team of the GREYC Lab in France and is available for Unix, Mac, and Windows systems under the CeCILL license. The algorithm is based on anisotropic diffusion partial differential equations. These equations are able to smooth an image while preserving its main structures. The demo page presents interesting examples of color image de-noising and reconstruction. This is a serious free alternative to commercial products like Noise Ninja or Neat Image that perform the same kinds of operations. The tool is still a little bit hard to use (command-line based), but I hope the simple C++ API will ease the integration of the algorithm in more user-friendly interfaces. Previous versions of GREYCstoration are already available in Digikam and Krita.
Can it remove the noise commonly used in CAPTCHA images? Will this be the next weapon in the war against spammers?
It seems to perform a lot better when dealing with artificially-added noises than real-life images, as if it already knows how to tackle them.
This pyramid photo has basically been 'ruined' after the denoising, I wonder if we added some synthetic noises in the background while leaving the stone face as is, would this app be able to denoise correctly?
Virtual Betting on Facebook for non-geeks.
It'd be useful to have a sample of the filter applied to video for denoising/scaling down, would be much easier to spot how good it actually is compared to other methods. It seems to introduce its own artifacts in the form of those swirly-patterns, would they look natural from frame-to-frame?
This looks like a great app to use for generating more detailed height maps for flight sims. You could zoom in on your height map to the location your aitcraft if flying towards use this tool to create a more detailed height map out of that smaller height map image and then wack that new mesh into your game as you get closer to the ground.
I understand GEGL will be the new backend for GIMP, supporting deeper color among other things. A friend closer to GIMP development mentioned to me that it may be ready for GIMP sometime this year, but neither the GEGL website or quick searches turn up anything on that topic. A 2003 thread stated that a move to GEGL would be very gradual so as not to necessitate major rewrites.
Fuji discontinued Velvia 50 because the new Velvia 100 produces images that looked as good, if not better. So there was no point to having a slower film when it was at best comparable to a faster one, especially in this day and age when low speed film is so unpopular.
I think you missed the GP's point
The idea is that you can eliminate blur caused by camera movement by taking many short exposures (high noise because of the short exposure), then align and average them together to eliminate the noise. This will work, but the downside is that it does require computationally intensive image alignment (to remove the camera movement that would have caused the blur in the first place) But that could be done offline.
Get a better camera and you won't need to clean them up at ISO 400 and sometimes not at ISO 1600. Nikons new entry level DSLR, the D40, can take outstanding photos at ISO 1600 and even boosted to 3200 looks better than most P&S cameras do at ISO 200-400.
Canon makes some terrific DSLRs as well, some with even better high ISO performance, I'm simply more familar with the Nikon line.
I cannot pretend to be a digital photo manipulation expert - but by your comments, you (implicitly) are.
I therefore challenge you to put your money where your mouth is, and clean up one of the sample images better than the filter, posting a link here.
I'm more impressed, if it's real, of the removal of the cage from the caged parrot photo: http://www.greyc.ensicaen.fr/~dtschump/greycstorat ion/img/res_zoobird.png
t ion/img/res_parrot.png
Similar, but less so: http://www.greyc.ensicaen.fr/~dtschump/greycstora