[trunk] As per T.809 code block are not shifted in JP3D

[trunk] As per T.809 code block are not shifted in JP3D

Table A.7
3D code-block width, height and depth exponent values xcb = value, ycb = value
or zcb = value.
NOTE – This redefines Rec. ITU-T T.800 | ISO/IEC 15444-1 significantly! The 3D
code-block width, height and depth are limited to powers of two with the minimum
size being 20 and the maximum being 210.
Further, the 3D code-block size is restricted so that 4 ≤ xcb+ycb+zcb ≤ 18.