bool generate_key_image_helper(const account_keys &ack, const std::unordered_map< crypto::public_key, subaddress_index > &subaddresses, const crypto::public_key &out_key, const crypto::public_key &tx_public_key, const std::vector< crypto::public_key > &additional_tx_public_keys, size_t real_output_index, keypair &in_ephemeral, crypto::key_image &ki, hw::device &hwdev, const uint32_t account_major_offset)