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luma concept
Petko Elenkin
2 Posts

Hello!

I'm currently doing analysis on light that enters a water tank. And when I create a linear profile of the water tank, I get a data column with title "luma". What does the program mean by "luma"? Lumens?


Replies to luma concept

Re: luma concept -
Douglas Brown Avatar
Douglas Brown
450 Posts

Luma is a measure of brightness that comes from the video world.  See https://en.wikipedia.org/wiki/Luma_(video).  Here's how Tracker calculate Luma (r, g and b are integers in the range 0-255):

public static double getLuma(double r, double g, double b) {
// following code based on CCIR 601 specs
return 0.299 * r + 0.587 * g + 0.114 * b;
}



Re: luma concept -
Petko Elenkin
2 Posts

Thank you very much!



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