"Sobel (3x3x3 -- 3sets -- x -90 y -90)	product"
3 3 7
3
-1	1	0	-1
	2	0	-2
	1	0	-1

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

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

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

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

2
-1	-1 	-2 	-1
	-2 	-4	-2
	-1 	-2 	-1

1	1 	2 	1
	2 	4 	2
	1	2 	1
