41 lines
1.1 KiB
C++
41 lines
1.1 KiB
C++
#include <istream>
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#include <unordered_map>
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#include "bitstream.h"
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#define HEADER_SIZE 128
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#define MAX_LEN 16
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#ifndef HUFFMAN_TABLE
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#define HUFFMAN_TABLE
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class HuffmanTable
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{
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private:
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std::unordered_map<char, std::pair<int, short> > huffmanCodes;
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std::vector<char> symbols;
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std::array<int, 16> counts;
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public:
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// Given the list of code lengths length[0..n-1] representing a canonical
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// Huffman code for n symbols, construct the tables required to decode those
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// codes.
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HuffmanTable(const char *header);
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// Build from input stream
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HuffmanTable(std::basic_istream<char> &is);
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char *to_header();
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std::pair<int, short> operator[](const char &c);
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void write_symbol(obitstream &os, const char &c);
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// Decode a code from the stream s using huffman table h. Return the symbol or
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// a negative value if there is an error. If all of the lengths are zero, i.e.
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// an empty code, or if the code is incomplete and an invalid code is received,
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// then IG_BAD_CODE_ERR is returned after reading MAXBITS bits.
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int decode_one_symbol(ibitstream &bs);
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};
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#endif
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