string Codegen::createCodeString(vector<FPCode> vCodes) {
    if (vCodes.size() < 3) {
        return "";
    }
    std::ostringstream codestream;
    codestream << std::setfill('0') << std::hex;
    for (uint i = 0; i < vCodes.size(); i++)
        codestream << std::setw(5) << vCodes[i].frame;

    for (uint i = 0; i < vCodes.size(); i++) {
        int hash = vCodes[i].code;
        codestream << std::setw(5) << hash;
    }
    return compress(codestream.str());
}