embdrv/lc3/Decoder/ArithmeticDec.hpp

/*
 * ArithmeticDec.hpp
 *
 * Copyright 2021 HIMSA II K/S - www.himsa.com. Represented by EHIMA -
 * www.ehima.com
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef __ARITHMETIC_DEC_HPP_
#define __ARITHMETIC_DEC_HPP_

#include <cstdint>

#include "Datapoints.hpp"

namespace Lc3Dec {

struct ac_dec_state {
  uint32_t low;
  uint32_t range;
};

class ArithmeticDec {
 public:
  ArithmeticDec(uint16_t NF_, uint16_t NE_, uint16_t rateFlag_,
                uint8_t tns_lpc_weighting_);
  virtual ~ArithmeticDec();

  void registerDatapoints(DatapointContainer* datapoints);

  double rc_q(uint8_t k, uint8_t f);

  void run(const uint8_t* bytes, uint16_t& bp, uint16_t& bp_side,
           uint8_t& mask_side, int16_t& num_tns_filters, int16_t rc_order[],
           const uint8_t& lsbMode, const int16_t& lastnz, uint16_t nbits,
           uint8_t& BEC_detect);

  const uint16_t NF;
  const uint16_t NE;
  const uint16_t rateFlag;
  const uint8_t tns_lpc_weighting;

  // states & outputs
  int16_t* X_hat_q_ari;
  uint8_t* save_lev;
  int16_t nf_seed;
  int16_t rc_order_ari[2];
  int16_t rc_i[2 * 8];  // [max(rc_order[f])=8][max(num_tns_filters)=2]
  uint16_t nbits_residual;

 private:
  struct ac_dec_state st;
};

}  // namespace Lc3Dec

#endif  // __ARITHMETIC_DEC_HPP_