Conversión de colores RGB a XYZ y LAB

Te sugerimos que revises esta resolución en un ambiente controlado antes de enviarlo a producción, saludos.

Solución:

Estoy bastante seguro ^ es bit a bit xor en javascript no es un operador de potencia. creo Math.pow es lo que buscas

/**
 * Converts RGB color to CIE 1931 XYZ color space.
 * https://www.image-engineering.de/library/technotes/958-how-to-convert-between-srgb-and-ciexyz
 * @param  string hex
 * @return number[]
 */
export function rgbToXyz(hex) 
    const [r, g, b] = hexToRgb(hex).map(_ => _ / 255).map(sRGBtoLinearRGB)
    const X =  0.4124 * r + 0.3576 * g + 0.1805 * b
    const Y =  0.2126 * r + 0.7152 * g + 0.0722 * b
    const Z =  0.0193 * r + 0.1192 * g + 0.9505 * b
    // For some reason, X, Y and Z are multiplied by 100.
    return [X, Y, Z].map(_ => _ * 100)


/**
 * Undoes gamma-correction from an RGB-encoded color.
 * https://en.wikipedia.org/wiki/SRGB#Specification_of_the_transformation
 * https://stackoverflow.com/questions/596216/formula-to-determine-brightness-of-rgb-color
 * @param  number
 * @return number
 */
function sRGBtoLinearRGB(color) 
    // Send this function a decimal sRGB gamma encoded color value
    // between 0.0 and 1.0, and it returns a linearized value.
    if (color <= 0.04045) 
        return color / 12.92
     else 
        return Math.pow((color + 0.055) / 1.055, 2.4)
    


/**
 * Converts hex color to RGB.
 * https://stackoverflow.com/questions/5623838/rgb-to-hex-and-hex-to-rgb
 * @param  string hex
 * @return number[] [rgb]
 */
function hexToRgb(hex) 
    const match = /^#?([a-fd]2)([a-fd]2)([a-fd]2)$/i.exec(hex)
    if (match) 
        match.shift()
        return match.map(_ => parseInt(_, 16))
    


/**
 * Converts CIE 1931 XYZ colors to CIE L*a*b*.
 * The conversion formula comes from .
 * https://github.com/cangoektas/xyz-to-lab/blob/master/src/index.js
 * @param   number[] color The CIE 1931 XYZ color to convert which refers to
 *                           the D65/2° standard illuminant.
 * @returns number[]       The color in the CIE L*a*b* color space.
 */
// X, Y, Z of a "D65" light source.
// "D65" is a standard 6500K Daylight light source.
// https://en.wikipedia.org/wiki/Illuminant_D65
const D65 = [95.047, 100, 108.883]
export function xyzToLab([x, y, z]) 
  [x, y, z] = [x, y, z].map((v, i) => 
    v = v / D65[i]
    return v > 0.008856 ? Math.pow(v, 1 / 3) : v * 7.787 + 16 / 116
  )
  const l = 116 * y - 16
  const a = 500 * (x - y)
  const b = 200 * (y - z)
  return [l, a, b]


/**
 * Converts Lab color space to Luminance-Chroma-Hue color space.
 * http://www.brucelindbloom.com/index.html?Eqn_Lab_to_LCH.html
 * @param  number[]
 * @return number[]
 */
export function labToLch([l, a, b]) 
    const c = Math.sqrt(a * a + b * b)
    const h = abToHue(a, b)
    return [l, c, h]


/**
 * Converts a and b of Lab color space to Hue of LCH color space.
 * https://stackoverflow.com/questions/53733379/conversion-of-cielab-to-cielchab-not-yielding-correct-result
 * @param  number a
 * @param  number b
 * @return number
 */
function abToHue(a, b) 
    if (a >= 0 && b === 0) 
        return 0
    
    if (a < 0 && b === 0) 
        return 180
    
    if (a === 0 && b > 0) 
        return 90
    
    if (a === 0 && b < 0) 
        return 270
    
    let xBias
    if (a > 0 && b > 0) 
        xBias = 0
     else if (a < 0) 
        xBias = 180
     else if (a > 0 && b < 0) 
        xBias = 360
    
    return radiansToDegrees(Math.atan(b / a)) + xBias


function radiansToDegrees(radians) 
    return radians * (180 / Math.PI)


function degreesToRadians(degrees) 
    return degrees * Math.PI / 180

Si te animas, tienes el poder dejar una crónica acerca de qué le añadirías a este artículo.

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