BOX_C2_SHIFT      675 3rdparty/libjpeg/jquant2.c   maxc2 = minc2 + ((1 << BOX_C2_SHIFT) - (1 << C2_SHIFT));
BOX_C2_SHIFT      884 3rdparty/libjpeg/jquant2.c   minc2 = (c2 << BOX_C2_SHIFT) + ((1 << C2_SHIFT) >> 1);