simple mp3 encoder c++

mp3encoder.cpp

#include <lame/lame.h>

struct Mp3Encoder {
  lame_global_flags *lame = nullptr;
  ~Mp3Encoder() {
    if (lame) {
      lame_close(lame);
      lame = nullptr;
    }
  }

  bool encodeMono(const float *samples, const int num_samples,
                  std::vector<unsigned char> &mp3Buffer) {
    mp3Buffer.resize(1.25 * num_samples + 7200);
    int result = lame_encode_buffer_ieee_float(
        lame,
        samples, // Input wave frames
        nullptr,
        num_samples,      // Number of samples in waveFrames
        mp3Buffer.data(), // Output buffer for encoded MP3 data
        mp3Buffer.size()  // Size of the output buffer
    );
    if (result < 0) {
      return false;
    }
    mp3Buffer.resize(result);
    return true;
  }

  static Mp3Encoder mono48k() {
    lame_global_flags *lame = lame_init();
    assert(lame);
    lame_set_quality(lame, 2);
    lame_set_in_samplerate(lame, 48000);
    lame_set_num_channels(lame, 1);
    lame_init_params(lame);
    return {lame};
  }
};