private function writeByte($byte) {
		// byte :    0b11010100
		// parity :          0b1
		// pixel 1 :   110
		// pixel 2 :      101
		// pixel 3 :         001

		list($x, $y) = $this->coordinates->current();
		$color = $this->getColor($x, $y);
		$color->writeBits(($byte>>5) & 7);
		$this->setColor($x, $y, $color);

		$this->coordinates->next();
		list($x, $y) = $this->coordinates->current();
		$color = $this->getColor($x, $y);
		$color->writeBits(($byte>>2) & 7);
		$this->setColor($x, $y, $color);

		$this->coordinates->next();
		list($x, $y) = $this->coordinates->current();
		$color = $this->getColor($x, $y);
		$color->writeBits(($byte<<1) & 7 | $this->parity($byte));
		$this->setColor($x, $y, $color);

		$this->coordinates->next();
	}