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#ifndef RC_QSMODEL_H
#define RC_QSMODEL_H
#include "types.h"
#include "rcmodel.h"
class RCqsmodel : public RCmodel {
public:
// initialization of model
// compress: true for compression, false for decompression
// symbols: number of symbols
// bits: log2 of total frequency count (must be <= 16)
// period: max symbols between normalizations (must be < 1<<(bits+1))
RCqsmodel(bool compress, uint symbols, uint bits = 16, uint period = 0x400);
~RCqsmodel();
// reinitialize model
void reset();
// get frequencies for a symbol s
void encode(uint s, uint& l, uint& r);
// return symbol corresponding to cumulative frequency l
uint decode(uint& l, uint& r);
// normalize range
void normalize(uint &r);
private:
void update();
void update(uint s);
const uint bits; // number of bits of precision for frequencies
uint left; // number of symbols until next normalization
uint more; // number of symbols with larger increment
uint incr; // increment per update
uint rescale; // current interval between normalizations
uint targetrescale; // target interval between rescales
uint* symf; // array of partially updated frequencies
uint* cumf; // array of cumulative frequencies
uint searchshift; // difference of frequency bits and table bits
uint* search; // structure for searching on decompression
};
#include "rcqsmodel.inl"
#endif