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/*

 * Copyright (c) 2016, Alliance for Open Media. All rights reserved.

 * This source code is subject to the terms of the BSD 2 Clause License and

 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License

 * was not distributed with this source code in the LICENSE file, you can

 * obtain it at www.aomedia.org/license/software. If the Alliance for Open

 * Media Patent License 1.0 was not distributed with this source code in the

 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.

*/

#ifndef AOM_AV1_ENCODER_COST_H_

#define AOM_AV1_ENCODER_COST_H_

#include "aom_dsp/prob.h"

#include "aom/aom_integer.h"

#ifdef __cplusplus

extern "C" {

#endif

extern const uint16_t av1_prob_cost[128];

// The factor to scale from cost in bits to cost in av1_prob_cost units.

#define AV1_PROB_COST_SHIFT 9

// Cost of coding an n bit literal, using 128 (i.e. 50%) probability

// for each bit.

#define av1_cost_literal(n) ((n) * (1 << AV1_PROB_COST_SHIFT))

// Calculate the cost of a symbol with probability p15 / 2^15

static inline int av1_cost_symbol(aom_cdf_prob p15) {

  // p15 can be out of range [1, CDF_PROB_TOP - 1]. Clamping it, so that the

  // following cost calculation works correctly. Otherwise, if p15 =

  // CDF_PROB_TOP, shift would be -1, and "p15 << shift" would be wrong.

  p15 = (aom_cdf_prob)clamp(p15, 1, CDF_PROB_TOP - 1);

  assert(0 < p15 && p15 < CDF_PROB_TOP);

  const int shift = CDF_PROB_BITS - 1 - get_msb(p15);

  const int prob = get_prob(p15 << shift, CDF_PROB_TOP);

  assert(prob >= 128);

  return av1_prob_cost[prob - 128] + av1_cost_literal(shift);

void av1_cost_tokens_from_cdf(int *costs, const aom_cdf_prob *cdf,

                              const int *inv_map);

#ifdef __cplusplus

}  // extern "C"

#endif

#endif  // AOM_AV1_ENCODER_COST_H_