const MV_PART: [i8; 16] = [ 0, 4, 8, 12, 16, 20, 24, 28, -32, -4, -8, -12, -16, -20, -24, -28 ];
let idx = br.read_byte()? as usize;
const MV_PART: [i8; 16] = [ 0, 4, 8, 12, 16, 20, 24, 28, -32, -4, -8, -12, -16, -20, -24, -28 ];
let idx = br.read_byte()? as usize;