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https://en.wikipedia.org/wiki/CIELUV
The article says, "The quantities uâ€²n and vâ€²n are the (uâ€², vâ€²)
chromaticity coordinates of a "specified white object" â€“ which may be
termed the white point â€“ and Yn is its luminance."
I have a D65 whitepoint:
#declare XYZWhiteReference = color <95.047,100.000,108.883>;
Which of these values is u'n, v'n and Yn?
Mike
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On 12/5/2016 9:13 PM, Mike Horvath wrote:
> I'm looking at the formulas for CIELUV color space on Wikipedia.
>
> https://en.wikipedia.org/wiki/CIELUV
>
> The article says, "The quantities uâ€²n and vâ€²n are the (uâ€², vâ€²)
> chromaticity coordinates of a "specified white object" â€“ which may be
> termed the white point â€“ and Yn is its luminance."
>
> I have a D65 whitepoint:
>
> #declare XYZWhiteReference = color <95.047,100.000,108.883>;
>
> Which of these values is u'n, v'n and Yn?
>
> Mike
Never mind. I will just use the code from ColorMine.org again.
Mike
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Am 06.12.2016 um 03:13 schrieb Mike Horvath:
> I'm looking at the formulas for CIELUV color space on Wikipedia.
>
> https://en.wikipedia.org/wiki/CIELUV
>
> The article says, "The quantities uâ€²n and vâ€²n are the (uâ€², vâ€²)
> chromaticity coordinates of a "specified white object" â€“ which may be
> termed the white point â€“ and Yn is its luminance."
>
> I have a D65 whitepoint:
>
> #declare XYZWhiteReference = color <95.047,100.000,108.883>;
>
> Which of these values is u'n, v'n and Yn?
Neither. Those three values are X, Y and Z, respectively. The formula
for converting these to u' and v' are given a few lines later in the
Wikipedia article:
u' = (4X) / (X + 15Y + 3Z)
v' = (9Y) / (X + 15Y + 3Z)
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On 12/5/2016 9:30 PM, Mike Horvath wrote:
> On 12/5/2016 9:13 PM, Mike Horvath wrote:
>> I'm looking at the formulas for CIELUV color space on Wikipedia.
>>
>> https://en.wikipedia.org/wiki/CIELUV
>>
>> The article says, "The quantities uâ€²n and vâ€²n are the (uâ€², vâ€²)
>> chromaticity coordinates of a "specified white object" â€“ which may be
>> termed the white point â€“ and Yn is its luminance."
>>
>> I have a D65 whitepoint:
>>
>> #declare XYZWhiteReference = color <95.047,100.000,108.883>;
>>
>> Which of these values is u'n, v'n and Yn?
>>
>> Mike
>
> Never mind. I will just use the code from ColorMine.org again.
>
> Mike
Link:
https://github.com/THEjoezack/ColorMine/blob/master/ColorMine/ColorSpaces/Conversions/LuvConverter.cs
Mike
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On 12/5/2016 9:31 PM, clipka wrote:
> Am 06.12.2016 um 03:13 schrieb Mike Horvath:
>> I'm looking at the formulas for CIELUV color space on Wikipedia.
>>
>> https://en.wikipedia.org/wiki/CIELUV
>>
>> The article says, "The quantities uâ€²n and vâ€²n are the (uâ€², vâ€²)
>> chromaticity coordinates of a "specified white object" â€“ which may be
>> termed the white point â€“ and Yn is its luminance."
>>
>> I have a D65 whitepoint:
>>
>> #declare XYZWhiteReference = color <95.047,100.000,108.883>;
>>
>> Which of these values is u'n, v'n and Yn?
>
> Neither. Those three values are X, Y and Z, respectively. The formula
> for converting these to u' and v' are given a few lines later in the
> Wikipedia article:
>
> u' = (4X) / (X + 15Y + 3Z)
> v' = (9Y) / (X + 15Y + 3Z)
>
Thanks!
Mike
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