/*

 * Copyright (c) 2021, 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.

 */

#include "av1/encoder/txb_rdopt.h"

#include "av1/encoder/txb_rdopt_utils.h"

#include "aom_ports/mem.h"

#include "av1/common/idct.h"

static inline void update_coeff_general(

    int *accu_rate, int64_t *accu_dist, int si, int eob, TX_SIZE tx_size,

    TX_CLASS tx_class, int bhl, int width, int64_t rdmult, int shift,

    int dc_sign_ctx, const int16_t *dequant, const int16_t *scan,

    const LV_MAP_COEFF_COST *txb_costs, const tran_low_t *tcoeff,

    tran_low_t *qcoeff, tran_low_t *dqcoeff, uint8_t *levels,

    const qm_val_t *iqmatrix, const qm_val_t *qmatrix) {

  const int dqv = get_dqv(dequant, scan[si], iqmatrix);

  const int ci = scan[si];

  const tran_low_t qc = qcoeff[ci];

  const int is_last = si == (eob - 1);

  const int coeff_ctx = get_lower_levels_ctx_general(

      is_last, si, bhl, width, levels, ci, tx_size, tx_class);

  if (qc == 0) {

    *accu_rate += txb_costs->base_cost[coeff_ctx][0];

  } else {

    const int sign = (qc < 0) ? 1 : 0;

    const tran_low_t abs_qc = abs(qc);

    const tran_low_t tqc = tcoeff[ci];

    const tran_low_t dqc = dqcoeff[ci];

    const int64_t dist = get_coeff_dist(tqc, dqc, shift, qmatrix, ci);

    const int64_t dist0 = get_coeff_dist(tqc, 0, shift, qmatrix, ci);

    const int rate =

        get_coeff_cost_general(is_last, ci, abs_qc, sign, coeff_ctx,

                               dc_sign_ctx, txb_costs, bhl, tx_class, levels);

    const int64_t rd = RDCOST(rdmult, rate, dist);

    tran_low_t qc_low, dqc_low;

    tran_low_t abs_qc_low;

    int64_t dist_low, rd_low;

    int rate_low;

    if (abs_qc == 1) {

      abs_qc_low = qc_low = dqc_low = 0;

      dist_low = dist0;

      rate_low = txb_costs->base_cost[coeff_ctx][0];

    } else {

      get_qc_dqc_low(abs_qc, sign, dqv, shift, &qc_low, &dqc_low);

      abs_qc_low = abs_qc - 1;

      dist_low = get_coeff_dist(tqc, dqc_low, shift, qmatrix, ci);

      rate_low =

          get_coeff_cost_general(is_last, ci, abs_qc_low, sign, coeff_ctx,

                                 dc_sign_ctx, txb_costs, bhl, tx_class, levels);

    }

    rd_low = RDCOST(rdmult, rate_low, dist_low);

    if (rd_low < rd) {

      qcoeff[ci] = qc_low;

      dqcoeff[ci] = dqc_low;

      levels[get_padded_idx(ci, bhl)] = AOMMIN(abs_qc_low, INT8_MAX);

      *accu_rate += rate_low;

      *accu_dist += dist_low - dist0;

    } else {

      *accu_rate += rate;

      *accu_dist += dist - dist0;

    }

  }

}

static AOM_FORCE_INLINE void update_coeff_simple(

    int *accu_rate, int si, int eob, TX_SIZE tx_size, TX_CLASS tx_class,

    int bhl, int64_t rdmult, int shift, const int16_t *dequant,

    const int16_t *scan, const LV_MAP_COEFF_COST *txb_costs,

    const tran_low_t *tcoeff, tran_low_t *qcoeff, tran_low_t *dqcoeff,

    uint8_t *levels, const qm_val_t *iqmatrix, const qm_val_t *qmatrix) {

  const int dqv = get_dqv(dequant, scan[si], iqmatrix);

  (void)eob;

  // this simple version assumes the coeff's scan_idx is not DC (scan_idx != 0)

  // and not the last (scan_idx != eob - 1)

  assert(si != eob - 1);

  assert(si > 0);

  const int ci = scan[si];

  const tran_low_t qc = qcoeff[ci];

  const int coeff_ctx =

      get_lower_levels_ctx(levels, ci, bhl, tx_size, tx_class);

  if (qc == 0) {

    *accu_rate += txb_costs->base_cost[coeff_ctx][0];

  } else {

    const tran_low_t abs_qc = abs(qc);

    const tran_low_t abs_tqc = abs(tcoeff[ci]);

    const tran_low_t abs_dqc = abs(dqcoeff[ci]);

    int rate_low = 0;

    const int rate = get_two_coeff_cost_simple(

        ci, abs_qc, coeff_ctx, txb_costs, bhl, tx_class, levels, &rate_low);

    if (abs_dqc < abs_tqc) {

      *accu_rate += rate;

      return;

    }

    const int64_t dist = get_coeff_dist(abs_tqc, abs_dqc, shift, qmatrix, ci);

    const int64_t rd = RDCOST(rdmult, rate, dist);

    const tran_low_t abs_qc_low = abs_qc - 1;

    const tran_low_t abs_dqc_low = (abs_qc_low * dqv) >> shift;

    const int64_t dist_low =

        get_coeff_dist(abs_tqc, abs_dqc_low, shift, qmatrix, ci);

    const int64_t rd_low = RDCOST(rdmult, rate_low, dist_low);

    if (rd_low < rd) {

      const int sign = (qc < 0) ? 1 : 0;

      qcoeff[ci] = (-sign ^ abs_qc_low) + sign;

      dqcoeff[ci] = (-sign ^ abs_dqc_low) + sign;

      levels[get_padded_idx(ci, bhl)] = AOMMIN(abs_qc_low, INT8_MAX);

      *accu_rate += rate_low;

    } else {

      *accu_rate += rate;

    }

  }

}

static AOM_FORCE_INLINE void update_coeff_eob(

    int *accu_rate, int64_t *accu_dist, int *eob, int *nz_num, int *nz_ci,

    int si, TX_SIZE tx_size, TX_CLASS tx_class, int bhl, int width,

    int dc_sign_ctx, int64_t rdmult, int shift, const int16_t *dequant,

    const int16_t *scan, const LV_MAP_EOB_COST *txb_eob_costs,

    const LV_MAP_COEFF_COST *txb_costs, const tran_low_t *tcoeff,

    tran_low_t *qcoeff, tran_low_t *dqcoeff, uint8_t *levels, int sharpness,

    const qm_val_t *iqmatrix, const qm_val_t *qmatrix) {

  const int dqv = get_dqv(dequant, scan[si], iqmatrix);

  assert(si != *eob - 1);

  const int ci = scan[si];

  const tran_low_t qc = qcoeff[ci];

  const int coeff_ctx =

      get_lower_levels_ctx(levels, ci, bhl, tx_size, tx_class);

  if (qc == 0) {

    *accu_rate += txb_costs->base_cost[coeff_ctx][0];

  } else {

    int lower_level = 0;

    const tran_low_t abs_qc = abs(qc);

    const tran_low_t tqc = tcoeff[ci];

    const tran_low_t dqc = dqcoeff[ci];

    const int sign = (qc < 0) ? 1 : 0;

    const int64_t dist0 = get_coeff_dist(tqc, 0, shift, qmatrix, ci);

    int64_t dist = get_coeff_dist(tqc, dqc, shift, qmatrix, ci) - dist0;

    int rate =

        get_coeff_cost_general(0, ci, abs_qc, sign, coeff_ctx, dc_sign_ctx,

                               txb_costs, bhl, tx_class, levels);

    int64_t rd = RDCOST(rdmult, *accu_rate + rate, *accu_dist + dist);

    tran_low_t qc_low, dqc_low;

    tran_low_t abs_qc_low;

    int64_t dist_low, rd_low;

    int rate_low;

    if (abs_qc == 1) {

      abs_qc_low = 0;

      dqc_low = qc_low = 0;

      dist_low = 0;

      rate_low = txb_costs->base_cost[coeff_ctx][0];

      rd_low = RDCOST(rdmult, *accu_rate + rate_low, *accu_dist);

    } else {

      get_qc_dqc_low(abs_qc, sign, dqv, shift, &qc_low, &dqc_low);

      abs_qc_low = abs_qc - 1;

      dist_low = get_coeff_dist(tqc, dqc_low, shift, qmatrix, ci) - dist0;

      rate_low =

          get_coeff_cost_general(0, ci, abs_qc_low, sign, coeff_ctx,

                                 dc_sign_ctx, txb_costs, bhl, tx_class, levels);

      rd_low = RDCOST(rdmult, *accu_rate + rate_low, *accu_dist + dist_low);

    }

    int lower_level_new_eob = 0;

    const int new_eob = si + 1;

    const int coeff_ctx_new_eob = get_lower_levels_ctx_eob(bhl, width, si);

    const int new_eob_cost =

        get_eob_cost(new_eob, txb_eob_costs, txb_costs, tx_class);

    int rate_coeff_eob =

        new_eob_cost + get_coeff_cost_eob(ci, abs_qc, sign, coeff_ctx_new_eob,

                                          dc_sign_ctx, txb_costs, bhl,

                                          tx_class);

    int64_t dist_new_eob = dist;

    int64_t rd_new_eob = RDCOST(rdmult, rate_coeff_eob, dist_new_eob);

    if (abs_qc_low > 0) {

      const int rate_coeff_eob_low =

          new_eob_cost + get_coeff_cost_eob(ci, abs_qc_low, sign,

                                            coeff_ctx_new_eob, dc_sign_ctx,

                                            txb_costs, bhl, tx_class);

      const int64_t dist_new_eob_low = dist_low;

      const int64_t rd_new_eob_low =

          RDCOST(rdmult, rate_coeff_eob_low, dist_new_eob_low);

      if (rd_new_eob_low < rd_new_eob) {

        lower_level_new_eob = 1;

        rd_new_eob = rd_new_eob_low;

        rate_coeff_eob = rate_coeff_eob_low;

        dist_new_eob = dist_new_eob_low;

      }

    }

    if (sharpness == 0 || abs_qc > 1) {

      if (rd_low < rd) {

        lower_level = 1;

        rd = rd_low;

        rate = rate_low;

        dist = dist_low;

      }

    }

    if (sharpness == 0 && rd_new_eob < rd) {

      for (int ni = 0; ni < *nz_num; ++ni) {

        int last_ci = nz_ci[ni];

        levels[get_padded_idx(last_ci, bhl)] = 0;

        qcoeff[last_ci] = 0;

        dqcoeff[last_ci] = 0;

      }

      *eob = new_eob;

      *nz_num = 0;

      *accu_rate = rate_coeff_eob;

      *accu_dist = dist_new_eob;

      lower_level = lower_level_new_eob;

    } else {

      *accu_rate += rate;

      *accu_dist += dist;

    }

    if (lower_level) {

      qcoeff[ci] = qc_low;

      dqcoeff[ci] = dqc_low;

      levels[get_padded_idx(ci, bhl)] = AOMMIN(abs_qc_low, INT8_MAX);

    }

    if (qcoeff[ci]) {

      nz_ci[*nz_num] = ci;

      ++*nz_num;

    }

  }

}

static inline void update_skip(int *accu_rate, int64_t accu_dist, int *eob,

                               int nz_num, int *nz_ci, int64_t rdmult,

                               int skip_cost, int non_skip_cost,

                               tran_low_t *qcoeff, tran_low_t *dqcoeff) {

  const int64_t rd = RDCOST(rdmult, *accu_rate + non_skip_cost, accu_dist);

  const int64_t rd_new_eob = RDCOST(rdmult, skip_cost, 0);

  if (rd_new_eob < rd) {

    for (int i = 0; i < nz_num; ++i) {

      const int ci = nz_ci[i];

      qcoeff[ci] = 0;

      dqcoeff[ci] = 0;

      // no need to set up levels because this is the last step

      // levels[get_padded_idx(ci, bhl)] = 0;

    }

    *accu_rate = 0;

    *eob = 0;

  }

}

// TODO(angiebird): use this function whenever it's possible

static int get_tx_type_cost(const MACROBLOCK *x, const MACROBLOCKD *xd,

                            int plane, TX_SIZE tx_size, TX_TYPE tx_type,

                            int reduced_tx_set_used) {

  if (plane > 0) return 0;

  const TX_SIZE square_tx_size = txsize_sqr_map[tx_size];

  const MB_MODE_INFO *mbmi = xd->mi[0];

  const int is_inter = is_inter_block(mbmi);

  if (get_ext_tx_types(tx_size, is_inter, reduced_tx_set_used) > 1 &&

      !xd->lossless[xd->mi[0]->segment_id]) {

    const int ext_tx_set =

        get_ext_tx_set(tx_size, is_inter, reduced_tx_set_used);

    if (is_inter) {

      if (ext_tx_set > 0)

        return x->mode_costs

            .inter_tx_type_costs[ext_tx_set][square_tx_size][tx_type];

    } else {

      if (ext_tx_set > 0) {

        PREDICTION_MODE intra_dir;

        if (mbmi->filter_intra_mode_info.use_filter_intra)

          intra_dir = fimode_to_intradir[mbmi->filter_intra_mode_info

                                             .filter_intra_mode];

        else

          intra_dir = mbmi->mode;

        return x->mode_costs.intra_tx_type_costs[ext_tx_set][square_tx_size]

                                                [intra_dir][tx_type];

      }

    }

  }

  return 0;

}

int av1_optimize_txb(const struct AV1_COMP *cpi, MACROBLOCK *x, int plane,

                     int block, TX_SIZE tx_size, TX_TYPE tx_type,

                     const TXB_CTX *const txb_ctx, int *rate_cost,

                     int sharpness) {

  MACROBLOCKD *xd = &x->e_mbd;

  const struct macroblock_plane *p = &x->plane[plane];

  const SCAN_ORDER *scan_order = get_scan(tx_size, tx_type);

  const int16_t *scan = scan_order->scan;

  const int shift = av1_get_tx_scale(tx_size);

  int eob = p->eobs[block];

  const int16_t *dequant = p->dequant_QTX;

  const qm_val_t *iqmatrix =

      av1_get_iqmatrix(&cpi->common.quant_params, xd, plane, tx_size, tx_type);

  const qm_val_t *qmatrix =

      cpi->oxcf.tune_cfg.dist_metric == AOM_DIST_METRIC_QM_PSNR

          ? av1_get_qmatrix(&cpi->common.quant_params, xd, plane, tx_size,

                            tx_type)

          : NULL;

  const int block_offset = BLOCK_OFFSET(block);

  tran_low_t *qcoeff = p->qcoeff + block_offset;

  tran_low_t *dqcoeff = p->dqcoeff + block_offset;

  const tran_low_t *tcoeff = p->coeff + block_offset;

  const CoeffCosts *coeff_costs = &x->coeff_costs;

  // This function is not called if eob = 0.

  assert(eob > 0);

  const AV1_COMMON *cm = &cpi->common;

  const PLANE_TYPE plane_type = get_plane_type(plane);

  const TX_SIZE txs_ctx = get_txsize_entropy_ctx(tx_size);

  const TX_CLASS tx_class = tx_type_to_class[tx_type];

  const MB_MODE_INFO *mbmi = xd->mi[0];

  const int bhl = get_txb_bhl(tx_size);

  const int width = get_txb_wide(tx_size);

  const int height = get_txb_high(tx_size);

  assert(height == (1 << bhl));

  const int is_inter = is_inter_block(mbmi);

  const LV_MAP_COEFF_COST *txb_costs =

      &coeff_costs->coeff_costs[txs_ctx][plane_type];

  const int eob_multi_size = txsize_log2_minus4[tx_size];

  const LV_MAP_EOB_COST *txb_eob_costs =

      &coeff_costs->eob_costs[eob_multi_size][plane_type];

  // For the IQ tune, increase rshift from 2 to 4.

  // This biases trellis quantization towards keeping more coefficients, and

  // together with the IQ rdmult adjustment in

  // av1_compute_rd_mult_based_on_qindex(), this helps preserve image

  // features (like repeating patterns and camera noise/film grain), which

  // improves SSIMULACRA 2 scores.

  const int rshift = cpi->oxcf.tune_cfg.tuning == AOM_TUNE_IQ ? 4 : 2;

  const int64_t rdmult = ROUND_POWER_OF_TWO(

      (int64_t)x->rdmult *

          (plane_rd_mult[is_inter][plane_type] << (2 * (xd->bd - 8))),

      rshift);

  uint8_t levels_buf[TX_PAD_2D];

  uint8_t *const levels = set_levels(levels_buf, height);

  if (eob > 1) av1_txb_init_levels(qcoeff, width, height, levels);

  // TODO(angirbird): check iqmatrix

  const int non_skip_cost = txb_costs->txb_skip_cost[txb_ctx->txb_skip_ctx][0];

  const int skip_cost = txb_costs->txb_skip_cost[txb_ctx->txb_skip_ctx][1];

  const int eob_cost = get_eob_cost(eob, txb_eob_costs, txb_costs, tx_class);

  int accu_rate = eob_cost;

  int64_t accu_dist = 0;

  int si = eob - 1;

  const int ci = scan[si];

  const tran_low_t qc = qcoeff[ci];

  const tran_low_t abs_qc = abs(qc);

  const int sign = qc < 0;

  const int max_nz_num = 2;

  int nz_num = 1;

  int nz_ci[3] = { ci, 0, 0 };

  if (abs_qc >= 2) {

    update_coeff_general(&accu_rate, &accu_dist, si, eob, tx_size, tx_class,

                         bhl, width, rdmult, shift, txb_ctx->dc_sign_ctx,

                         dequant, scan, txb_costs, tcoeff, qcoeff, dqcoeff,

                         levels, iqmatrix, qmatrix);

    --si;

  } else {

    assert(abs_qc == 1);

    const int coeff_ctx = get_lower_levels_ctx_eob(bhl, width, si);

    accu_rate +=

        get_coeff_cost_eob(ci, abs_qc, sign, coeff_ctx, txb_ctx->dc_sign_ctx,

                           txb_costs, bhl, tx_class);

    const tran_low_t tqc = tcoeff[ci];

    const tran_low_t dqc = dqcoeff[ci];

    const int64_t dist = get_coeff_dist(tqc, dqc, shift, qmatrix, ci);

    const int64_t dist0 = get_coeff_dist(tqc, 0, shift, qmatrix, ci);

    accu_dist += dist - dist0;

    --si;

  }

#define UPDATE_COEFF_EOB_CASE(tx_class_literal)                            \

  case tx_class_literal:                                                   \

    for (; si >= 0 && nz_num <= max_nz_num; --si) {                        \

      update_coeff_eob(&accu_rate, &accu_dist, &eob, &nz_num, nz_ci, si,   \

                       tx_size, tx_class_literal, bhl, width,              \

                       txb_ctx->dc_sign_ctx, rdmult, shift, dequant, scan, \

                       txb_eob_costs, txb_costs, tcoeff, qcoeff, dqcoeff,  \

                       levels, sharpness, iqmatrix, qmatrix);              \

    }                                                                      \

    break

  switch (tx_class) {

    UPDATE_COEFF_EOB_CASE(TX_CLASS_2D);

    UPDATE_COEFF_EOB_CASE(TX_CLASS_HORIZ);

    UPDATE_COEFF_EOB_CASE(TX_CLASS_VERT);

#undef UPDATE_COEFF_EOB_CASE

    default: assert(false);

  }

  if (si == -1 && nz_num <= max_nz_num && sharpness == 0) {

    update_skip(&accu_rate, accu_dist, &eob, nz_num, nz_ci, rdmult, skip_cost,

                non_skip_cost, qcoeff, dqcoeff);

  }

#define UPDATE_COEFF_SIMPLE_CASE(tx_class_literal)                             \

  case tx_class_literal:                                                       \

    for (; si >= 1; --si) {                                                    \

      update_coeff_simple(&accu_rate, si, eob, tx_size, tx_class_literal, bhl, \

                          rdmult, shift, dequant, scan, txb_costs, tcoeff,     \

                          qcoeff, dqcoeff, levels, iqmatrix, qmatrix);         \

    }                                                                          \

    break

  switch (tx_class) {

    UPDATE_COEFF_SIMPLE_CASE(TX_CLASS_2D);

    UPDATE_COEFF_SIMPLE_CASE(TX_CLASS_HORIZ);

    UPDATE_COEFF_SIMPLE_CASE(TX_CLASS_VERT);

#undef UPDATE_COEFF_SIMPLE_CASE

    default: assert(false);

  }

  // DC position

  if (si == 0) {

    // no need to update accu_dist because it's not used after this point

    int64_t dummy_dist = 0;

    update_coeff_general(&accu_rate, &dummy_dist, si, eob, tx_size, tx_class,

                         bhl, width, rdmult, shift, txb_ctx->dc_sign_ctx,

                         dequant, scan, txb_costs, tcoeff, qcoeff, dqcoeff,

                         levels, iqmatrix, qmatrix);

  }

  const int tx_type_cost = get_tx_type_cost(x, xd, plane, tx_size, tx_type,

                                            cm->features.reduced_tx_set_used);

  if (eob == 0)

    accu_rate += skip_cost;

  else

    accu_rate += non_skip_cost + tx_type_cost;

  p->eobs[block] = eob;

  p->txb_entropy_ctx[block] =

      av1_get_txb_entropy_context(qcoeff, scan_order, p->eobs[block]);

  *rate_cost = accu_rate;

  return eob;

}

static AOM_FORCE_INLINE int warehouse_efficients_txb(

    const MACROBLOCK *x, const int plane, const int block,

    const TX_SIZE tx_size, const TXB_CTX *const txb_ctx,

    const struct macroblock_plane *p, const int eob,

    const PLANE_TYPE plane_type, const LV_MAP_COEFF_COST *const coeff_costs,

    const MACROBLOCKD *const xd, const TX_TYPE tx_type, const TX_CLASS tx_class,

    int reduced_tx_set_used) {

  const tran_low_t *const qcoeff = p->qcoeff + BLOCK_OFFSET(block);

  const int txb_skip_ctx = txb_ctx->txb_skip_ctx;

  const int bhl = get_txb_bhl(tx_size);

  const int width = get_txb_wide(tx_size);

  const int height = get_txb_high(tx_size);

  const SCAN_ORDER *const scan_order = get_scan(tx_size, tx_type);

  const int16_t *const scan = scan_order->scan;

  uint8_t levels_buf[TX_PAD_2D];

  uint8_t *const levels = set_levels(levels_buf, height);

  DECLARE_ALIGNED(16, int8_t, coeff_contexts[MAX_TX_SQUARE]);

  const int eob_multi_size = txsize_log2_minus4[tx_size];

  const LV_MAP_EOB_COST *const eob_costs =

      &x->coeff_costs.eob_costs[eob_multi_size][plane_type];

  int cost = coeff_costs->txb_skip_cost[txb_skip_ctx][0];

  av1_txb_init_levels(qcoeff, width, height, levels);

  cost += get_tx_type_cost(x, xd, plane, tx_size, tx_type, reduced_tx_set_used);

  cost += get_eob_cost(eob, eob_costs, coeff_costs, tx_class);

  av1_get_nz_map_contexts(levels, scan, eob, tx_size, tx_class, coeff_contexts);

  const int(*lps_cost)[COEFF_BASE_RANGE + 1 + COEFF_BASE_RANGE + 1] =

      coeff_costs->lps_cost;

  int c = eob - 1;

  {

    const int pos = scan[c];

    const tran_low_t v = qcoeff[pos];

    const int sign = AOMSIGN(v);

    const int level = (v ^ sign) - sign;

    const int coeff_ctx = coeff_contexts[pos];

    cost += coeff_costs->base_eob_cost[coeff_ctx][AOMMIN(level, 3) - 1];

    if (v) {

      // sign bit cost

      if (level > NUM_BASE_LEVELS) {

        const int ctx = get_br_ctx_eob(pos, bhl, tx_class);

        cost += get_br_cost(level, lps_cost[ctx]);

      }

      if (c) {

        cost += av1_cost_literal(1);

      } else {

        const int sign01 = (sign ^ sign) - sign;

        const int dc_sign_ctx = txb_ctx->dc_sign_ctx;

        cost += coeff_costs->dc_sign_cost[dc_sign_ctx][sign01];

        return cost;

      }

    }

  }

  const int(*base_cost)[8] = coeff_costs->base_cost;

  for (c = eob - 2; c >= 1; --c) {

    const int pos = scan[c];

    const int coeff_ctx = coeff_contexts[pos];

    const tran_low_t v = qcoeff[pos];

    const int level = abs(v);

    cost += base_cost[coeff_ctx][AOMMIN(level, 3)];

    if (v) {

      // sign bit cost

      cost += av1_cost_literal(1);

      if (level > NUM_BASE_LEVELS) {

        const int ctx = get_br_ctx(levels, pos, bhl, tx_class);

        cost += get_br_cost(level, lps_cost[ctx]);

      }

    }

  }

  // c == 0 after previous loop

  {

    const int pos = scan[c];

    const tran_low_t v = qcoeff[pos];

    const int coeff_ctx = coeff_contexts[pos];

    const int sign = AOMSIGN(v);

    const int level = (v ^ sign) - sign;

    cost += base_cost[coeff_ctx][AOMMIN(level, 3)];

    if (v) {

      // sign bit cost

      const int sign01 = (sign ^ sign) - sign;

      const int dc_sign_ctx = txb_ctx->dc_sign_ctx;

      cost += coeff_costs->dc_sign_cost[dc_sign_ctx][sign01];

      if (level > NUM_BASE_LEVELS) {

        const int ctx = get_br_ctx(levels, pos, bhl, tx_class);

        cost += get_br_cost(level, lps_cost[ctx]);

      }

    }

  }

  return cost;

}

/*!\brief Estimate the entropy cost of transform coefficients using Laplacian

 * distribution.

 *

 * \ingroup coefficient_coding

 *

 * This function assumes each transform coefficient is of its own Laplacian

 * distribution and the coefficient is the only observation of the Laplacian

 * distribution.

 *

 * Based on that, each coefficient's coding cost can be estimated by computing

 * the entropy of the corresponding Laplacian distribution.

 *

 * This function then return the sum of the estimated entropy cost for all

 * coefficients in the transform block.

 *

 * Note that the entropy cost of end of block (eob) and transform type (tx_type)

 * are not included.

 *

 * \param[in]    x              Pointer to structure holding the data for the

                                current encoding macroblock

 * \param[in]    plane          The index of the current plane

 * \param[in]    block          The index of the current transform block in the

 * macroblock. It's defined by number of 4x4 units that have been coded before

 * the currernt transform block

 * \param[in]    tx_size        The transform size

 * \param[in]    tx_type        The transform type

 * \return       int            Estimated entropy cost of coefficients in the

 * transform block.

 */

static int av1_cost_coeffs_txb_estimate(const MACROBLOCK *x, const int plane,

                                        const int block, const TX_SIZE tx_size,

                                        const TX_TYPE tx_type) {

  assert(plane == 0);

  int cost = 0;

  const struct macroblock_plane *p = &x->plane[plane];

  const SCAN_ORDER *scan_order = get_scan(tx_size, tx_type);

  const int16_t *scan = scan_order->scan;

  tran_low_t *qcoeff = p->qcoeff + BLOCK_OFFSET(block);

  int eob = p->eobs[block];

  // coeffs

  int c = eob - 1;

  // eob

  {

    const int pos = scan[c];

    const tran_low_t v = abs(qcoeff[pos]) - 1;

    cost += (v << (AV1_PROB_COST_SHIFT + 2));

  }

  // other coeffs

  for (c = eob - 2; c >= 0; c--) {

    const int pos = scan[c];

    const tran_low_t v = abs(qcoeff[pos]);

    const int idx = AOMMIN(v, 14);

    cost += costLUT[idx];

  }

  // const_term does not contain DC, and log(e) does not contain eob, so both

  // (eob-1)

  cost += (const_term + loge_par) * (eob - 1);

  return cost;

}

static AOM_FORCE_INLINE int warehouse_efficients_txb_laplacian(

    const MACROBLOCK *x, const int plane, const int block,

    const TX_SIZE tx_size, const TXB_CTX *const txb_ctx, const int eob,

    const PLANE_TYPE plane_type, const LV_MAP_COEFF_COST *const coeff_costs,

    const MACROBLOCKD *const xd, const TX_TYPE tx_type, const TX_CLASS tx_class,

    int reduced_tx_set_used) {

  const int txb_skip_ctx = txb_ctx->txb_skip_ctx;

  const int eob_multi_size = txsize_log2_minus4[tx_size];

  const LV_MAP_EOB_COST *const eob_costs =

      &x->coeff_costs.eob_costs[eob_multi_size][plane_type];

  int cost = coeff_costs->txb_skip_cost[txb_skip_ctx][0];

  cost += get_tx_type_cost(x, xd, plane, tx_size, tx_type, reduced_tx_set_used);

  cost += get_eob_cost(eob, eob_costs, coeff_costs, tx_class);

  cost += av1_cost_coeffs_txb_estimate(x, plane, block, tx_size, tx_type);

  return cost;

}

int av1_cost_coeffs_txb(const MACROBLOCK *x, const int plane, const int block,

                        const TX_SIZE tx_size, const TX_TYPE tx_type,

                        const TXB_CTX *const txb_ctx, int reduced_tx_set_used) {

  const struct macroblock_plane *p = &x->plane[plane];

  const int eob = p->eobs[block];

  const TX_SIZE txs_ctx = get_txsize_entropy_ctx(tx_size);

  const PLANE_TYPE plane_type = get_plane_type(plane);

  const LV_MAP_COEFF_COST *const coeff_costs =

      &x->coeff_costs.coeff_costs[txs_ctx][plane_type];

  if (eob == 0) {

    return coeff_costs->txb_skip_cost[txb_ctx->txb_skip_ctx][1];

  }

  const MACROBLOCKD *const xd = &x->e_mbd;

  const TX_CLASS tx_class = tx_type_to_class[tx_type];

  return warehouse_efficients_txb(x, plane, block, tx_size, txb_ctx, p, eob,

                                  plane_type, coeff_costs, xd, tx_type,

                                  tx_class, reduced_tx_set_used);

}

int av1_cost_coeffs_txb_laplacian(const MACROBLOCK *x, const int plane,

                                  const int block, const TX_SIZE tx_size,

                                  const TX_TYPE tx_type,

                                  const TXB_CTX *const txb_ctx,

                                  const int reduced_tx_set_used,

                                  const int adjust_eob) {

  const struct macroblock_plane *p = &x->plane[plane];

  int eob = p->eobs[block];

  if (adjust_eob) {

    const SCAN_ORDER *scan_order = get_scan(tx_size, tx_type);

    const int16_t *scan = scan_order->scan;

    tran_low_t *tcoeff = p->coeff + BLOCK_OFFSET(block);

    tran_low_t *qcoeff = p->qcoeff + BLOCK_OFFSET(block);

    tran_low_t *dqcoeff = p->dqcoeff + BLOCK_OFFSET(block);

    update_coeff_eob_fast(&eob, av1_get_tx_scale(tx_size), p->dequant_QTX, scan,

                          tcoeff, qcoeff, dqcoeff);

    p->eobs[block] = eob;

  }

  const TX_SIZE txs_ctx = get_txsize_entropy_ctx(tx_size);

  const PLANE_TYPE plane_type = get_plane_type(plane);

  const LV_MAP_COEFF_COST *const coeff_costs =

      &x->coeff_costs.coeff_costs[txs_ctx][plane_type];

  if (eob == 0) {

    return coeff_costs->txb_skip_cost[txb_ctx->txb_skip_ctx][1];

  }

  const MACROBLOCKD *const xd = &x->e_mbd;

  const TX_CLASS tx_class = tx_type_to_class[tx_type];

  return warehouse_efficients_txb_laplacian(

      x, plane, block, tx_size, txb_ctx, eob, plane_type, coeff_costs, xd,

      tx_type, tx_class, reduced_tx_set_used);

}