br.rewindNbits(num_bits - part2_3_end); index-=4;
br.rewindNbits(num_bits - part2_3_end); index-=4;
br.rewindNbits(num_bits - part2_3_end); index-=4;
br.rewindNbits(num_bits - part2_3_end); index -= 4;
br.rewindNbits(num_bits - part2_3_end); index -= 4;