std::string get_afilter_desc()

in torchaudio/csrc/ffmpeg/prototype.cpp [124:156]

• 32 lines of code
• 9 McCabe index (conditional complexity)

std::string get_afilter_desc(
    const c10::optional<int64_t>& sample_rate,
    const c10::optional<c10::ScalarType>& dtype) {
  std::vector<std::string> components;
  if (sample_rate) {
    // TODO: test float sample rate
    components.emplace_back(
        string_format("aresample=%d", static_cast<int>(sample_rate.value())));
  }
  if (dtype) {
    AVSampleFormat fmt = [&]() {
      switch (dtype.value()) {
        case c10::ScalarType::Byte:
          return AV_SAMPLE_FMT_U8P;
        case c10::ScalarType::Short:
          return AV_SAMPLE_FMT_S16P;
        case c10::ScalarType::Int:
          return AV_SAMPLE_FMT_S32P;
        case c10::ScalarType::Long:
          return AV_SAMPLE_FMT_S64P;
        case c10::ScalarType::Float:
          return AV_SAMPLE_FMT_FLTP;
        case c10::ScalarType::Double:
          return AV_SAMPLE_FMT_DBLP;
        default:
          throw std::runtime_error("Unexpected dtype.");
      }
    }();
    components.emplace_back(
        string_format("aformat=sample_fmts=%s", av_get_sample_fmt_name(fmt)));
  }
  return join(components, ",");
}