如何计算颜色像素的数量或找出图像中的部分颜色(js)？

<img id="image" src="image.jpg" />

var image = document.getElementById('image');
var canvas = document.createElement('canvas');
var context = canvas.getContext('2d');
context.drawImage(image, 0, 0);
var imageData = context.getImageData(0, 0, image.width, image.height);
var pixels = imageData.data;

var targetColor = [255, 0, 0]; // 目标颜色，这里以红色为例
var count = 0; // 颜色像素数量计数器

for (var i = 0; i < pixels.length; i += 4) {
  var red = pixels[i];
  var green = pixels[i + 1];
  var blue = pixels[i + 2];

  if (red === targetColor[0] && green === targetColor[1] && blue === targetColor[2]) {
    count++;
  }
}

console.log('颜色像素数量：', count);