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/* Copyright (C) Teemu Suutari */
#ifndef RANGEDECODER_HPP
#define RANGEDECODER_HPP
#include <cstdint>
namespace ancient::internal
{
// used by too many compressors...
class RangeDecoder
{
public:
class BitReader
{
public:
BitReader() noexcept=default;
virtual ~BitReader() noexcept=default;
virtual uint32_t readBit()=0;
};
RangeDecoder(BitReader &bitReader,uint16_t initialValue);
~RangeDecoder() noexcept=default;
uint16_t decode(uint16_t length);
void scale(uint16_t newLow,uint16_t newHigh,uint16_t newRange);
private:
BitReader &_bitReader;
uint16_t _low{0};
uint16_t _high{0xffffU};
uint16_t _stream;
};
}
#endif
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