pack unpack bits

bits.cpp

template <class T, class InputIt, class OutputIt>
void pack_bits_to(InputIt first, InputIt last, OutputIt d_first)
{
    static_assert(std::is_integral<T>::value);

    while (first != last) {
        DataType buf = 0;

        for (std::size_t i = 0; i < 8 * sizeof(T); ++i) {
            bool bit = (first != last) ? (*(first++)) : 0;
            buf = buf | static_cast<DataType>(bit << i);
        }

        *(d_first++) = buf;
    }
}

template <class T, class InputIt, class OutputIt>
void unpack_bits_from(InputIt first, InputIt last, OutputIt d_first)
{
    static_assert(std::is_integral<T>::value);

    while (first != last) {
        for (std::size_t i = 0; i < 8 * sizeof(T); ++i) {
            *(d_first++) = (1 & (*first >> i));
        }
        ++first;
    }
}