score-avnd-senior/Ottobit/OttobitModel.cpp

#include "Ottobit.hpp"

namespace Example
{
void Ottobit::operator()(tick t)
{
  // Only compute bit_factor when the control changes
  if (inputs.bits != previous_bits)
  {
    set_bit_factor();
    previous_bits = inputs.bits;
  }

  // Only compute skipped_frames when the control changes
  if (inputs.rate != previous_rate)
  {
    step_size = (1. - inputs.rate) * RATE;
    previous_rate = inputs.rate;
    qDebug() << "step size: " << step_size;
  }

  // Process the input buffer
  for(int i = 0; i < inputs.audio.channels; i++)
  {
    auto* in = inputs.audio[i];
    auto* out = outputs.audio[i];

    // Re-init skipped_frames and current_frame for each channel
    skipped_frames = 0;
    current_frame = in[0];

    for(int j = 0; j < t.frames; j++)
    {
      if (skipped_frames <= step_size)
        skipped_frames++;
      else
      {
        skipped_frames = 0;

        if (inputs.bits == BITS)
          current_frame = in[j];
        else
        {
          int in_scaled{static_cast<int>((in[j] + 1) * bit_factor)};
          current_frame = (static_cast<double>(in_scaled) / bit_factor) - 1;
        }
      }

      out[j] = current_frame;
    }
  }
}

void Ottobit::set_bit_factor()
{
  bit_factor = pow(2, inputs.bits) - 1;
}
}