Legacy ImageMagick Discussions Archive

Thanks Pete,
It is really very slow, i found a new direction, as you mention at beginning, i do need the Polynomial of the curves.
P = d[0]*p^3 + d[1]*p^2 + d[2]*p + d[3];
and pass all those vaule in *d to
MagickFunctionImageChannel(magick_wand_local,RedChannel,PolynomialFunction,4,d);

That works ...

Hi Fred, thanks for you quick reply
http://www.flickr.com/photos/59931911@N05/5474937051/

the right corner is the original image,
the left image curves effect.

I want to simulator this effect with IM API.

Now i can do this with command line:
convert test.png -channel B -fx '(1/(1+exp(10*(.5-u ...

Fred, thank you. Your script helped me very much when i study the IM.

My problem now is how to translate the script to API argument.
like


http://www.imagemagick.org/Usage/transform/#function_polynomial
convert gradient.png -function Polynomial 4,-4,1 func_parabola.png


just cant figure out ...

Hey Guys, i try to simulate the curve in photoshop by using MagicWand.
I tried MagickFunctionImageChannel, it works well when i only has two arguments, as below:

double d[4];
d[0] = 0.0; d[1] = 0.0; d[2] = 1.0; d[3] = 0.5;
status = MagickFunctionImageChannel(magick_wand_local,RedChannel ...