color_matrix_filter.js

colorMatrixFilter = function (pixels, m) {
  var d = pixels.data;
  for (var i = 0; i < d.length; i += 4) {
    var r = d[i];
    var g = d[i + 1];
    var b = d[i + 2]; 
    var a = d[i + 3];

    d[i]   = r * m[0] + g * m[1] + b * m[2] + a * m[3] + m[4];
    d[i+1] = r * m[5] + g * m[6] + b * m[7] + a * m[8] + m[9];
    d[i+2] = r * m[10]+ g * m[11]+ b * m[12]+ a * m[13]+ m[14];
    d[i+3] = r * m[15]+ g * m[16]+ b * m[17]+ a * m[18]+ m[19]; 
  }
  return pixels;
};