calcScale         746 source/encoder/ratecontrol.cpp     hrd->bitRateScale = x265_clip3(0, 15, calcScale(vbvMaxBitrate) - BR_SHIFT);
calcScale         749 source/encoder/ratecontrol.cpp     hrd->cpbSizeScale = x265_clip3(0, 15, calcScale(vbvBufferSize) - CPB_SHIFT);