private int[][] extractMovements(byte[] b) {
		int[][] movs = new int[b.length - 8][4];
		for (int i = 0; i < b.length - 8; ++i) {
			switch (b[i + 8]) {
			case Constants.EAST:
				movs[i][3] = 1;
				break;
			case Constants.NORTH:
				movs[i][0] = 1;
				break;
			case Constants.NORTHEAST:
				movs[i][3] = 1;
				movs[i][0] = 1;
				break;
			case Constants.NORTHWEST:
				movs[i][0] = 1;
				movs[i][2] = 1;
				break;
			case Constants.SOUTH:
				movs[i][1] = 1;
				break;
			case Constants.SOUTHEAST:
				movs[i][1] = 1;
				movs[i][3] = 1;
				break;
			case Constants.SOUTHWEST:
				movs[i][1] = 1;
				movs[i][2] = 1;
				break;
			case Constants.WEST:
				movs[i][2] = 1;
				break;

			default:
				break;
			}
		}
		return movs;

	}