annotate FastBitDecoder.hpp @ 55:19b2a2d98788

Use define to multiplex between different types of decoders. Expand the API.
author Tom Fredrik Blenning Klaussen <bfg@blenning.no>
date Thu, 13 Sep 2012 23:47:29 +0200
parents f8d0ea827db3
children c8111de2e0bb
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1 #ifndef FASTBITDECODER_HPP
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2 #define FASTBITDECODER_HPP
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4 #include "BitArray.hpp"
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6 #include <QtCore/QString>
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7 #include <QtCore/QMap>
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9 class FastBitDecoder {
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10 static const size_t N = 256;
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11 FastBitDecoder* decoder[N];
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12 unsigned char numBits[N];
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13 QString* data[N];
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15 static unsigned char getPaddedChar(const BitArray& bitArray, uint offset = 0);
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16 static BitArray removeFirst(const BitArray& bits);
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18 void fill();
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19 void blank();
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20 FastBitDecoder();
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21 void insert(const BitArray& key, const QString& value);
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22 uint decode(QString& resString, const BitArray& bits, uint offset) const;
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23
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24 public:
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25 FastBitDecoder(const QMap<QString, BitArray>& encoder);
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26 QString decode(const BitArray& bits) const
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27 {
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28 QString combined;
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29 uint n = bits.size();
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30 //Just a qualified overestimate guess on what we will need.
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31 combined.reserve(n/4);
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32 for (uint decodedBits = 0; decodedBits < n; decodedBits += decode(combined, bits, decodedBits));
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33 combined.squeeze();
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34 return combined;
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35 }
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36 QString decode(const QString& bits) const;
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39 };
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41 #endif //BITDECODER_HPP