Programmatically determine the average greyscale
J. Landman Gay
jacque at hyperactivesw.com
Thu Feb 18 21:27:14 EST 2016
On 2/18/2016 5:05 PM, Sannyasin Brahmanathaswami wrote:
> But if I use white type on top of the image and the sky appears there
> in the top left area of the image is a light color, then we have a
> problem with contrast/readability.
> Is there a way to get the "average" grayscale value of a small area
> of a photo?
I'm not sure about getting an average, but someone posted the following
handler here a while ago. I'm sorry I can't give credit, I should have
Determine whether to show white or black text against a colored background:
function calcLuminance pRGB
-- wikipedia: Y = 0.2126 R + 0.7152 G + 0.0722 B
put item 1 of pRGB * 0.2126 into tR
put item 2 of pRGB * 0.7152 into tG
put item 3 of pRGB * 0.0722 into tB
if sum(tR,tG,tB) > 125 then return "black"
else return "white"
Jacqueline Landman Gay | jacque at hyperactivesw.com
HyperActive Software | http://www.hyperactivesw.com
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