When I use UIColor and give R G B as input and then screen capture and check R G B values the values are not same! What is problem, is iOS applying a sort color management?
UIColor displays incorrect color
250 Views Asked by AVEbrahimi At
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The screen-capture feature doesn't save with 100% accuracy. This happens because of performance-issues.
There is "mostly" nothing you can do about it, except editing the photo afterwards to get the exact color values you want.
Edit 1
I'm not sure if this has anything to do with it, but under
Settings->Accessibility->Increase Contrast
you can choose to darken colors. Maybe this also affects your label, view or wherever you've set the UIColor.
Try turning it off
I just wrote a little app that generates random colors for views and it displays the colors and RGB values in a table. I ran this on an iPhone 6 and did a screen capture of the screens showing the colors and RGB values. Then I used AirDrop to move the screen captures back to the Mac. When I opened the screen captures in a photo editing program (Pixelmator), the RGB values matched exactly those values reported by the app.
I just repeated the experiment with an iPod touch 5th Generation (introduced Fall 2012), and again the colors matched exactly.
Here is an example screen capture:
Update:
Another poster suggested in the comments that perhaps the Increase Contrast settings under Settings->Accessibility were changing the RGB values. I just tried changing both Reduce White Point and Darken Colors and found that while the screen looked different, the RGB values of the screen captures were still a match to the values reported by the app.