0

I have been trying to recreate a filter effect used in GIMP (photoshop) in an iPhone application.

and here is an example which shows the tool:

https://drive.google.com/file/d/0B5dHxpdDwpPeYnk5WU81X0RQTlU/view?usp=sharing https://drive.google.com/file/d/0B5dHxpdDwpPeUF8zMFptY3RNUmM/view?usp=sharing

So from what I understand the lightness changes each specifics color brightness (which is not achieved by changing the brightness in general)

now the question is how do I do that to a UIImage?

I tried changing the HSL/HSB of the whole image but that doesn't give me the right effect.

Thank you for your time

Leonardo Murri
  • 40
  • 7
  • This is what the GIMP docs say about this kind of transformation : Lightness changes here concern a color range, while they concern a color tone with Curves and Levels tools, which work on color channels. If you change the Yellow lightness with Hue-Saturation, all yellow pixels will be changed, while only dark, bright or medium pixels luminosity will be changed with Curves or Levels tools. – Leonardo Murri Apr 04 '15 at 17:59
  • So did you look for a way to do with this with one or more CIFilters? – matt Apr 04 '15 at 18:01
  • yes, I can't find a way to apply a filter to a specific color in the uiimage only – Leonardo Murri Apr 04 '15 at 18:05
  • 1
    http://stackoverflow.com/questions/633722/how-to-make-one-color-transparent-on-a-uiimage this might be on the right track? – Leonardo Murri Apr 04 '15 at 18:20

0 Answers0