question about initial acc_bais and initial gyrp_scale ?

hi:
     please tell me how to compute the init_acc_calib and  init_gyro_calib?

    init_acc_calib.setBias( Vector3d(32768, 32768, 32768) );
    init_gyro_calib.setScale( Vector3d(1.0/6258.0, 1.0/6258.0, 1.0/6258.0) );

thanks alot!!! @Kyle-ak 