BOX_C2_SHIFT      674 jquant2.c        maxc2 = minc2 + ((1 << BOX_C2_SHIFT) - (1 << C2_SHIFT));
BOX_C2_SHIFT      883 jquant2.c        minc2 = (c2 << BOX_C2_SHIFT) + ((1 << C2_SHIFT) >> 1);