r property

num r

@override
num get r => palette == null
    ? numChannels > 0
        ? data[_index]
        : 0
    : palette!.getRed(data[_index]);

void r=(num r)

@override
set r(num r) {
  if (image.numChannels > 0) {
    data[_index] = r.clamp(0, 255).toInt();
  }
}