Function getContrastColor

web/js/main.js:871–874

(r, g, b)

}

function getContrastColor(r, g, b) {
    const yiq = (r * 299 + g * 587 + b * 114) / 1000;
    return yiq >= 150 ? '#000000' : '#FFFFFF';
}

function extract1x1Grid(imageData, blockSize) {
    const src = imageData.data;