Answer: How does Twitter extract meaningful subject colors from image pixel data?

Nov 14 '17

Something like the example below might be found helpful for what you want to accomplish.

function getAverageColourAsRGB(img) {
  var canvas = document.createElement('canvas'),
    context = canvas.getContext && canvas.getContext('2d'),
    rgb = {
      r: 102,
      g: 102,
      b: 102
    },
    pixelInterval = 5,
    count = 0,
    i = -4,
    data, length;

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