}

std::vector<char> UnpackDenseInt4IntoInt8(
    const std::vector<uint8_t>& src_buffer, int64_t num_elements) {
  std::vector<char> unpacked_buffer;
  unpacked_buffer.reserve(num_elements);

  for (uint8_t value : src_buffer) {
    // Cast to signed before right-shifting to ensure correct sign extension
    unpacked_buffer.push_back(static_cast<int8_t>(value << 4) >> 4);
    unpacked_buffer.push_back(static_cast<int8_t>(value) >> 4);

    }
    auto packed_buffer = tflite::PackInt4ValuesDensely(data);
    if (use_buffer_offset_) {
      buffer_data_map_[index] =
          std::string(packed_buffer.begin(), packed_buffer.end());
      return tflite::CreateBuffer(builder_, 0, 1, 1);
    } else {
      if (IsModelBiggerThan2GB(packed_buffer.size())) {
        require_use_buffer_offset_ = true;