"Sobel (3x3x3 -- 2sets -- z x-90)	max_abs"
3 2 1
3
-1	1 	0	-1
	2 	1	-2
	1 	0	-1

0	2	0	-2
	4	4	-4
	2	0	-2


1	1 	0	-1
	2 	1	-2
	1 	0	-1
3
-1	 1	 2	 1
	 0	 1	 0
	-1	-2	-1

0	 2	 4	 2
	 0	 4	 0
	-2	-4	-2

1	 1	 2	 1
	 0	 1	 0
	-1	-2	-1
