static void
run(LV2_Handle instance,
    uint32_t n_samples)
{
  Denoiser* denoiser = (Denoiser*)instance;

  const float* const input_left = denoiser->input_left;
  const float* const input_right = denoiser->input_right;
  float* const output_left = denoiser->output_left;
  float* const output_right = denoiser->output_right;

  const float sample_rate = denoiser->sample_rate;

  float bw = *(denoiser->bandwidth);
  float freq = *(denoiser->center_freq);
  float k; // intermediate variable for calculating coefficients
  float r; // ^
  float a0,a1,a2,b1,b2; // IIR filter coefficients
  float o_lb1,o_lb2, o_rb1, o_rb2; // previous left and right outputs
  float i_lb1, i_lb2, i_rb1, i_rb2; // previous left and right inputs

  r = 1 - (3*(bw/sample_rate));
  k = ( 1 - (2*r*cos(2*PI*(freq/sample_rate))) + (r*r) ) / ( 2 - (2*PI*(freq/sample_rate)) );

  a0 = k;
  a1 = -2*k*cos(2*PI*(freq/sample_rate));
  a2 = k;
  b1 = 2*r*cos(2*PI*(freq/sample_rate));
  b2 = -1*(r*r);

  o_lb1 = denoiser->o_lb1;
  o_lb2 = denoiser->o_lb2;
  o_rb1 = denoiser->o_rb1;
  o_rb2 = denoiser->o_rb2;

  i_lb1 = denoiser->i_lb1;
  i_lb2 = denoiser->i_lb2;
  i_rb1 = denoiser->i_rb1;
  i_rb2 = denoiser->i_rb2;

  for(int i = 0; i < n_samples ; i ++){
    output_left[i] = (a0*input_left[i]) + (a1*i_lb1) + (a2*i_lb2) + (b1*o_lb1) + (b2*o_lb2);

    denoiser->i_lb2 = i_lb1;
    denoiser->i_lb1 = input_left[i];
    denoiser->o_lb2 = o_lb1;
    denoiser->o_lb1 = output_left[i];

    output_right[i] = (a0*input_right[i]) + (a1*i_rb1) + (a2*i_rb2) + (b1*o_rb1) + (b2*o_rb2);

    denoiser->i_rb2 = i_rb1;
    denoiser->i_rb1 = input_right[i];
    denoiser->o_rb2 = o_rb1;
    denoiser->o_rb1 = output_right[i];
  }
}