int work(int noutput_items,
	   gr_vector_const_void_star &input_items,
	   gr_vector_void_star &output_items)
  {
    const std::complex<float> *in = reinterpret_cast<const std::complex<float> *>(input_items[0]);
    float *out = reinterpret_cast<float *>(output_items[0]);
    std::complex<float> conjin[4], prod[4];
    float angle[4];
    gruel::high_res_timer_type t1, t2, tit;
    
    t1 = gruel::high_res_timer_now();

    for(int i = 0; i < noutput_items; i+=4){
      conjin[0] = conj(in[i]);
      conjin[1] = conj(in[i+1]);
      conjin[2] = conj(in[i+2]);
      conjin[3] = conj(in[i+3]);

      const std::complex<float> *p1 = reinterpret_cast<const std::complex<float> *>(&in[i+1]);
      const std::complex<float> *p2 = reinterpret_cast<const std::complex<float> *>(conjin);
      volk_32fc_x2_multiply_32fc_a(prod, p1, p2, 4);

      for(int j = 0; j < 4; j++)
	angle[j] = gr_fast_atan2f(imag(prod[j]), real(prod[j]));

      const float *p3 = reinterpret_cast<const float *>(angle);
      volk_32f_s32f_multiply_32f_a(&out[i], p3, d_gain, 4);
    }

    t2 = gruel::high_res_timer_now();

    tit = t2 - t1;

    printf(">> time to demod one [%d] buffer: %lld ticks\n", noutput_items, tit);

    return noutput_items;
  }