On Tue, 24 Apr 2007 09:09:39 +1000 Anthony Thyssen <[EMAIL PROTECTED]> wrote:
> Micha Feigin on wrote... > | On Sun, 22 Apr 2007 15:49:40 -0700 > | [EMAIL PROTECTED] wrote: > | > | > > The problem is that image magick adds way too much noise and I can't > seem | > > | > Did you try using a different type of noise? You can choose from uniform, > | > gaussian, multiplicative, impulse, laplacian, and poisson. ImageMagick > has | > built in constants associated with each noise type. We could make the > | > constants a parameter to the noise method. > | > > | > | yes, except for poisson which does virtually nothing, all the rest leave me > | with noise with no image. > | > | Besides, the type of noise is important for most applications. > | > | Seems like I need to hack the imagemagick code. > > No need to go that far... > > The -fx function can add noise in a some way you specify. > For example a random offset, to each color... > > convert rose: -fx 'u+random()*.2-.1' rose_noisy.png > I am looking to do it from inside a c++ (or c, doesn't matter) program > However you are probably right about the lack of control with noise. > A number of very old option did not get the control that they should > have had, which is now giving us problems. the question is exactly > what type of control is wanted. > The parameters would be a bit different depending on the type of noise, so the right method of input would take some thought, but mean and standard deviation for Gaussian noise or density for salt and pepper noise (don't remember if there is such). I don't remember the required parameters for the others at the moment (statistical signal processing is one of my weak spots regrettably) > > Anthony Thyssen ( System Programmer ) <[EMAIL PROTECTED]> > ----------------------------------------------------------------------------- > Take this cheese to sick bay!!! > The Doctor should have a look at it. > -- StarTrek Voyager "Training" > ----------------------------------------------------------------------------- > Anthony's Home is his Castle http://www.cit.gu.edu.au/~anthony/ > _______________________________________________ Magick-users mailing list [email protected] http://studio.imagemagick.org/mailman/listinfo/magick-users
