RGB to LAB Color Converter & Calculator

function rgbToLab(r, g, b) {
    // RGB to LAB conversion in JavaScript
    // Input: RGB values (0-255)
    // Output: LAB values
    
    // Step 1: Normalize RGB to [0,1] and apply gamma correction
    let rNorm = r / 255;
    let gNorm = g / 255;
    let bNorm = b / 255;
    
    // Gamma correction
    rNorm = rNorm > 0.04045 ? Math.pow((rNorm + 0.055) / 1.055, 2.4) : rNorm / 12.92;
    gNorm = gNorm > 0.04045 ? Math.pow((gNorm + 0.055) / 1.055, 2.4) : gNorm / 12.92;
    bNorm = bNorm > 0.04045 ? Math.pow((bNorm + 0.055) / 1.055, 2.4) : bNorm / 12.92;
    
    // Step 2: RGB to XYZ conversion (D65 illuminant)
    let x = rNorm * 0.4124564 + gNorm * 0.3575761 + bNorm * 0.1804375;
    let y = rNorm * 0.2126729 + gNorm * 0.7151522 + bNorm * 0.0721750;
    let z = rNorm * 0.0193339 + gNorm * 0.1191920 + bNorm * 0.9503041;
    
    // Step 3: XYZ to LAB conversion
    x = x / 0.95047;  // D65 illuminant normalization
    y = y / 1.00000;
    z = z / 1.08883;
    
    const fx = x > 0.008856 ? Math.pow(x, 1/3) : (7.787 * x + 16/116);
    const fy = y > 0.008856 ? Math.pow(y, 1/3) : (7.787 * y + 16/116);
    const fz = z > 0.008856 ? Math.pow(z, 1/3) : (7.787 * z + 16/116);
    
    const L = 116 * fy - 16;
    const a = 500 * (fx - fy);
    const b = 200 * (fy - fz);
    
    return { L: L, a: a, b: b };
}

// Example usage:
const rgb = { r: 255, g: 128, b: 64 };
const lab = rgbToLab(rgb.r, rgb.g, rgb.b);
console.log(`RGB(${rgb.r}, ${rgb.g}, ${rgb.b}) = LAB(${lab.L.toFixed(2)}, ${lab.a.toFixed(2)}, ${lab.b.toFixed(2)})`);