View source for Talk:Color presets

@Raffriff42,

I don't know what formula's you used to calculated the HSL values but they seem to be wrong.
[http://en.wikipedia.org/wiki/HSL_and_HSV Wikipedia] contains the formula's where 0<=H<360.0, 0<=S<=1 and 0<=L<=255.
I suggest you use those. Example (color_blueviolet):

R = 138 <br>
G = 043 <br>
B = 226 <br>
M = max(R,G,B) = 226 <br>
m = min(R,G,B) = 43 <br>
C = M - m = 183 <br>
B = M => H = 60*(4+(R-G)/C) = 60*(4+(138-43)/183) = 271.15 <br>
L = (M+m)/2 = 134.5 <br>
S = C/(255-|2*L-255|) = 183/(255-|2*134.5-255|) = 0.76 <br>

Also you should add an appropriate reference for this. [[User:Admin|Admin]] 00:18, 19 August 2014 (CEST)

:Sure thing, I created RGB '''BlankClip'''s with the values from '''colors_rgb.avsi''', converted to YV12 with matrix="PC.601", and calculated hue as 

::[http://forum.doom9.org/showthread.php?p=1670625#post1670625 atan2](VPlaneMedian-128, UPlaneMedian-128)*180/PI + 360) % 360

:My complete script is posted here: [https://dl.dropboxusercontent.com/u/108089426/Code/avisynth-Colors%7E2.avs] [[User:Raffriff42|Raffriff42]] 15:31, 19 August 2014 (CEST)

::The values you posted stand for hue, saturation and luma derived of the YCbCr colorspace (you should have converted to yv24 instead). I suggest you name it (HSL)_ycbcr or something like that. Since the colorpresets are given in rgb values it would make more sense to include (HSL)_rgb instead. [[User:Admin|Admin]] 16:04, 19 August 2014 (CEST)

:::Added a boxed note. What do you think? [[User:Raffriff42|Raffriff42]] 19:57, 19 August 2014 (CEST)