On 18 Jun 2014, at 12:04 am, Maxthon Chan wrote:
> moronically
:)
monotonically? But maybe both are true!
--Graham
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Contac
Once again, you don’t need to perform the square root before comparing. It is a
waste of processor resource and not doing ti will not throw off comparison
(since mathematically, square root function is moronically increasing.)
On Jun 17, 2014, at 22:02, Jonathan Taylor
wrote:
> Thanks everyone
you may wish to look up ‘Delta E’. [what has this to do w/ cocoa?]
On Jun 17, 2014, at 9:29 AM, Maxthon Chan wrote:
> Alternatively I have an idea based on HSB colours: difference in hue in
> radians raised to 4th power (or 6th) plus squared Euclidean distance of
> saturation and brightness.
Thanks everyone. I had thought there might be a pre-existing API that would do
this (I was half expecting to find a method defined for the NSColorList
class...), but I will implement the euclidean distance test myself...
Cheers
Jonny.
On 17 Jun 2014, at 12:43, Maxthon Chan wrote:
> One easy-to
Alternatively I have an idea based on HSB colours: difference in hue in radians
raised to 4th power (or 6th) plus squared Euclidean distance of saturation and
brightness.
On Jun 17, 2014, at 21:22, Torsten Curdt wrote:
> RGB is not perceptually uniform, hence the Euclidean distance is not qui
I know, it is just sqared Euclidean distance is simplest to calculate. Sure you
can, for example, add coefficients to the formula, to adjust.
On Jun 17, 2014, at 21:22, Torsten Curdt wrote:
> RGB is not perceptually uniform, hence the Euclidean distance is not quite
> right.
> Wikipedia and St
RGB is not perceptually uniform, hence the Euclidean distance is not quite
right.
Wikipedia and Stackoverflow has more information on this:
http://en.wikipedia.org/wiki/Color_difference
http://stackoverflow.com/questions/9018016/how-to-compare-two-colors
cheers,
Torsten
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On Jun 17, 2014, at 7:14 AM, Mills, Steve wrote:
> The algorithm I've seen then takes the square root of that value.
If the square root of a is larger than the square root of b, then a is larger
than b ;-)
(In this case a & b will both be positive.)
--
Scott Ribe
scott_r...@elevated-dev.com
Square rooting is slow, and not calculating square root do not throw off
comparison.
On Jun 17, 2014, at 21:14, Mills, Steve wrote:
> On Jun 17, 2014, at 06:43:54, Maxthon Chan wrote:
>
>> One easy-to-implement method: colour cube.
>>
>> Define a colour using its RGB values as a 3-tuple (r,
On Jun 17, 2014, at 06:43:54, Maxthon Chan wrote:
> One easy-to-implement method: colour cube.
>
> Define a colour using its RGB values as a 3-tuple (r, g, b) and standard
> colours (ri, gi, bi) (where i = 0..n).The square distance between the given
> colour and a standard colour is (ri-r)^2+(
One easy-to-implement method: colour cube.
Define a colour using its RGB values as a 3-tuple (r, g, b) and standard
colours (ri, gi, bi) (where i = 0..n).The square distance between the given
colour and a standard colour is (ri-r)^2+(gi-g)^2+(bi-b)^2. You can calculate
square distances between
Hi all,
Is there a way of identifying the closest match to a given NSColor, out of a
list of possible colors to match? The user could have selected any color using
the color picker, but I would like to know whether it is "approximately red",
green, blue or white.
Of course, it might be e.g. ma
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