wav.cpp

//
// Created by Eldar Sadykov on 23.12.25.
//

#include "wav.hpp"

#include <fstream>

void writeWav(const char *filename,
              const std::vector<float> &samples,
              int sampleRate)
{
  std::ofstream file(filename, std::ios::binary);

  int dataSize = static_cast<int>(samples.size() * sizeof(int16_t));
  int fileSize = 36 + dataSize;

  file.write("RIFF", 4);
  file.write(reinterpret_cast<char *>(&fileSize), 4);
  file.write("WAVEfmt ", 8);

  int subChunk1Size = 16;
  short audioFormat = 1;
  short numChannels = 1;
  int byteRate = sampleRate * numChannels * 2;
  auto blockAlign = static_cast<short>(numChannels * 2);
  short bitsPerSample = 16;

  file.write(reinterpret_cast<char *>(&subChunk1Size), 4);
  file.write(reinterpret_cast<char *>(&audioFormat), 2);
  file.write(reinterpret_cast<char *>(&numChannels), 2);
  file.write(reinterpret_cast<char *>(&sampleRate), 4);
  file.write(reinterpret_cast<char *>(&byteRate), 4);
  file.write(reinterpret_cast<char *>(&blockAlign), 2);
  file.write(reinterpret_cast<char *>(&bitsPerSample), 2);

  file.write("data", 4);
  file.write(reinterpret_cast<char *>(&dataSize), 4);

  for (float s: samples)
  {
    int16_t v = static_cast<int16_t>(std::clamp(s, -1.0f, 1.0f) * 32767);
    file.write(reinterpret_cast<char *>(&v), 2);
  }
}