Make image to white using canvas(enchant.js)

canvas.js

machine1Canvas.draw(game.assets['./images/mc_01.png']);
var oldImg = machine1Canvas.clone();
machine1_old.image = oldImg;
var imgData = machine1Canvas.context.getImageData(0, 0, 742, 498);
oldImgData = imgData;

function setWhite() {
  for (var i = 0; i < 369516 * 4; i += 4) {
    imgData.data[i] = 255;
    imgData.data[i + 1] = 255;
    imgData.data[i + 2] = 255;
  }
  machine1Canvas.context.putImageData(imgData, 0, 0);
}
setWhite();