Original Data:
 [   0  -1  -2  -3  -4  -5  -6]
 [   0   0   0   0   0   0   0]
 [   0   1   2   3   4   5   6]
 [   0   2   4   6   8  10  12]

Data as written with transform "x+1":
 [   1   0  -1  -2  -3  -4  -5]
 [   1   1   1   1   1   1   1]
 [   1   2   3   4   5   6   7]
 [   1   3   5   7   9  11  13]

Data as written with transform "x+1" and read with transform "x-1":
 [   0  -1  -2  -3  -4  -5  -6]
 [   0   0   0   0   0   0   0]
 [   0   1   2   3   4   5   6]
 [   0   2   4   6   8  10  12]