webdriverio-automation
Version:
WebdriverIO-Automation android ios project
29 lines (24 loc) • 827 B
text/typescript
/**
* @preserve
* Copyright 2015-2016 Igor Bezkrovnyi
* All rights reserved. (MIT Licensed)
*
* xyz2lab.ts - part of Image Quantization Library
*/
const refX : number = 0.95047, //ref_X = 95.047 Observer= 2°, Illuminant= D65
refY : number = 1.00000, //ref_Y = 100.000
refZ : number = 1.08883; //ref_Z = 108.883
function pivot(n : number) : number {
return n > 0.008856 ? Math.pow(n, 1 / 3) : ( 7.787 * n + 16 / 116);
}
export function xyz2lab(x : number, y : number, z : number) : {L : number; a : number; b : number} {
x = pivot(x / refX);
y = pivot(y / refY);
z = pivot(z / refZ);
if (( 116 * y ) - 16 < 0) throw new Error("xxx")
return {
L : Math.max(0, ( 116 * y ) - 16),
a : 500 * ( x - y ),
b : 200 * ( y - z )
}
}