JSFiddle - React, Tailwind, and code Playground

HTML

<span id="colorValue"><</span>

JavaScript

var img = new Image();
img.src = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAgAAAAICAYAAADED76LAAAAAXNSR0IArs4c6QAAARNJREFUKFMBCAH3/gEz9Cj/ElT2AGlVYQCR4jUAmbYOAFmftgAHrFUAAo1hAAFyPPX/+8eKACL+kwDqCToAD3xEAHGAfwBxH8wAeoRuAAEPuTr/d3uEAK4AuAClQfEAlA6ZAKeFmwAIkdUAjxRFAAGhz2r/z+33AEFmpAAKJmMAH27jAM+EtABtWnEAVewYAAG1f8v/Q3HzAMhyzwAk4fcA0KXXAJXmdQDBZtUA0X1FAAFhAUf/MvduAHB5hgAd8IcASUKfAMEm+wBJheQAIXb8AAHjczr/EMjKAAVfGQCtqfMAXKaPAHZcDADK7rgAou/8AAFwMVD/jSlsAMNnVwB0VakA0nsSAAQQrADvR40Ah2NMALV8aFgYGaUMAAAAAElFTkSuQmCCNzAwMDQx';

img.onload = e => {
  var canvas = document.createElement("canvas");
  canvas.width = img.width;
  canvas.height = img.height;
  var ctx = canvas.getContext('2d');
  ctx.imageSmoothingEnabled = false;
  ctx.drawImage(img, 0, 0);
  var pix = ctx.getImageData(0, 0, img.width, img.height).data;
  var pixValue = pix[208];
  document.getElementById("colorValue").textContent = 'Pixel value:' + pixValue + 
  	(pixValue == 1 ? '(true value)' : '(wrong value!)');
};