I could imagine, you create a java script action with this code from https://www.reddit.com/r/learnjavascript/comments/31glai/color_selector_help/
$(window).on("click", function(ev) {
var x = ev.clientX;
var y = ev.clientY;
html2canvas(document.body).then(function(canvas) {
var ctx = canvas.getContext('2d');
var p = ctx.getImageData(x, y, 1, 1).data;
var hex = "#" + ("000000" + rgbToHex(p[0], p[1], p[2])).slice(-6);
console.log(hex);
});
});
No there is not as far as I know. I think your best option is to modify the Color picker widget by replacing its color palette by an uploadable image.