std::vector<std::string> get_all_files_names_within_folder(std::string folder) {

	std::vector<std::string> names;
	std::string search_path = folder + "/*.*";
	std::string fullFilename;
	WIN32_FIND_DATA fd;
	HANDLE hFind = ::FindFirstFile(search_path.c_str(), &fd);

	if (hFind != INVALID_HANDLE_VALUE) {
		int index = 0;
		do {
			if (!(fd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)) {
				fullFilename = fd.cFileName;
				// we not save jpg files
				if (fullFilename.substr(fullFilename.find_last_of(".") + 1).find("jpg") == std::string::npos) {
					std::string fullname = folder;
					fullname.append(fd.cFileName);
					names.push_back(fullname);
				}

			}
		} while (::FindNextFile(hFind, &fd));

		::FindClose(hFind);
		const size_t last_slash_idx = folder.find_last_of("\\/");

		if (std::string::npos != last_slash_idx)
		{
			folder.erase(0, last_slash_idx + 1);
		}

		return names;

	}
}