git / moonbite-core / src/util/golombrice.h · raw

// Copyright (c) 2018-2019 The Bitcoin Core developers// Distributed under the MIT software license, see the accompanying// file COPYING or http://www.opensource.org/licenses/mit-license.php.#ifndef BITCOIN_UTIL_GOLOMBRICE_H#define BITCOIN_UTIL_GOLOMBRICE_H#include <streams.h>#include <cstdint>template <typename OStream>void GolombRiceEncode(BitStreamWriter<OStream>& bitwriter, uint8_t P, uint64_t x){    // Write quotient as unary-encoded: q 1's followed by one 0.    uint64_t q = x >> P;    while (q > 0) {        int nbits = q <= 64 ? static_cast<int>(q) : 64;        bitwriter.Write(~0ULL, nbits);        q -= nbits;    }    bitwriter.Write(0, 1);    // Write the remainder in P bits. Since the remainder is just the bottom    // P bits of x, there is no need to mask first.    bitwriter.Write(x, P);}template <typename IStream>uint64_t GolombRiceDecode(BitStreamReader<IStream>& bitreader, uint8_t P){    // Read unary-encoded quotient: q 1's followed by one 0.    uint64_t q = 0;    while (bitreader.Read(1) == 1) {        ++q;    }    uint64_t r = bitreader.Read(P);    return (q << P) + r;}#endif // BITCOIN_UTIL_GOLOMBRICE_H