text: /*
   * 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.
   */
  
  #include <assert.h>
  
  #include "av1/common/cfl.h"
  #include "av1/common/common.h"
  #include "av1/common/entropy.h"
  #include "av1/common/entropymode.h"
  #include "av1/common/entropymv.h"
  #include "av1/common/mvref_common.h"
  #include "av1/common/pred_common.h"
  #include "av1/common/reconinter.h"
  #include "av1/common/reconintra.h"
  #include "av1/common/seg_common.h"
  #include "av1/common/warped_motion.h"
  
  #include "av1/decoder/decodeframe.h"
  #include "av1/decoder/decodemv.h"
  
  #include "aom_dsp/aom_dsp_common.h"
  
  #define ACCT_STR __func__
  
  #define DEC_MISMATCH_DEBUG 0
  
  static PREDICTION_MODE read_intra_mode(aom_reader *r, aom_cdf_prob *cdf) {
    return (PREDICTION_MODE)aom_read_symbol(r, cdf, INTRA_MODES, ACCT_STR);
  }
  
  static void read_cdef(AV1_COMMON *cm, aom_reader *r, MACROBLOCKD *const xd,
                        int mi_col, int mi_row) {
    MB_MODE_INFO *const mbmi = xd->mi[0];
    if (cm->coded_lossless) return;
    if (cm->allow_intrabc) {
      assert(cm->cdef_bits == 0);
      return;
    }
  
    if (!(mi_col & (cm->seq_params.mib_size - 1)) &&
        !(mi_row & (cm->seq_params.mib_size - 1))) {  // Top left?
      xd->cdef_preset[0] = xd->cdef_preset[1] = xd->cdef_preset[2] =
          xd->cdef_preset[3] = -1;
    }
    // Read CDEF param at the first non-skip coding block
    const int mask = (1 << (6 - MI_SIZE_LOG2));
    const int m = ~(mask - 1);
    const int index = cm->seq_params.sb_size == BLOCK_128X128
                          ? !!(mi_col & mask) + 2 * !!(mi_row & mask)
                          : 0;
    cm->mi_grid_visible[(mi_row & m) * cm->mi_stride + (mi_col & m)]
        ->cdef_strength = xd->cdef_preset[index] =
        xd->cdef_preset[index] == -1 && !mbmi->skip
            ? aom_read_literal(r, cm->cdef_bits, ACCT_STR)
            : xd->cdef_preset[index];
  }
  
  static int read_delta_qindex(AV1_COMMON *cm, const MACROBLOCKD *xd,
                               aom_reader *r, MB_MODE_INFO *const mbmi,
                               int mi_col, int mi_row) {
    int sign, abs, reduced_delta_qindex = 0;
    BLOCK_SIZE bsize = mbmi->sb_type;
    const int b_col = mi_col & (cm->seq_params.mib_size - 1);
    const int b_row = mi_row & (cm->seq_params.mib_size - 1);
    const int read_delta_q_flag = (b_col == 0 && b_row == 0);
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  
    if ((bsize != cm->seq_params.sb_size || mbmi->skip == 0) &&
        read_delta_q_flag) {
      abs = aom_read_symbol(r, ec_ctx->delta_q_cdf, DELTA_Q_PROBS + 1, ACCT_STR);
      const int smallval = (abs < DELTA_Q_SMALL);
  
      if (!smallval) {
        const int rem_bits = aom_read_literal(r, 3, ACCT_STR) + 1;
        const int thr = (1 << rem_bits) + 1;
        abs = aom_read_literal(r, rem_bits, ACCT_STR) + thr;
      }
  
      if (abs) {
        sign = aom_read_bit(r, ACCT_STR);
      } else {
        sign = 1;
      }
  
      reduced_delta_qindex = sign ? -abs : abs;
    }
    return reduced_delta_qindex;
  }
  static int read_delta_lflevel(AV1_COMMON *cm, const MACROBLOCKD *xd,
                                aom_reader *r, int lf_id,
                                MB_MODE_INFO *const mbmi, int mi_col,
                                int mi_row) {
    int sign, abs, reduced_delta_lflevel = 0;
    BLOCK_SIZE bsize = mbmi->sb_type;
    const int b_col = mi_col & (cm->seq_params.mib_size - 1);
    const int b_row = mi_row & (cm->seq_params.mib_size - 1);
    const int read_delta_lf_flag = (b_col == 0 && b_row == 0);
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  
    if ((bsize != cm->seq_params.sb_size || mbmi->skip == 0) &&
        read_delta_lf_flag) {
      if (cm->delta_lf_multi) {
        assert(lf_id >= 0 &&
               lf_id < (av1_num_planes(cm) > 1 ? FRAME_LF_COUNT
                                               : FRAME_LF_COUNT - 2));
        abs = aom_read_symbol(r, ec_ctx->delta_lf_multi_cdf[lf_id],
                              DELTA_LF_PROBS + 1, ACCT_STR);
      } else {
        abs = aom_read_symbol(r, ec_ctx->delta_lf_cdf, DELTA_LF_PROBS + 1,
                              ACCT_STR);
      }
      const int smallval = (abs < DELTA_LF_SMALL);
      if (!smallval) {
        const int rem_bits = aom_read_literal(r, 3, ACCT_STR) + 1;
        const int thr = (1 << rem_bits) + 1;
        abs = aom_read_literal(r, rem_bits, ACCT_STR) + thr;
      }
  
      if (abs) {
        sign = aom_read_bit(r, ACCT_STR);
      } else {
        sign = 1;
      }
  
      reduced_delta_lflevel = sign ? -abs : abs;
    }
    return reduced_delta_lflevel;
  }
  
  static UV_PREDICTION_MODE read_intra_mode_uv(FRAME_CONTEXT *ec_ctx,
                                               aom_reader *r,
                                               CFL_ALLOWED_TYPE cfl_allowed,
                                               PREDICTION_MODE y_mode) {
    const UV_PREDICTION_MODE uv_mode =
        aom_read_symbol(r, ec_ctx->uv_mode_cdf[cfl_allowed][y_mode],
                        UV_INTRA_MODES - !cfl_allowed, ACCT_STR);
    return uv_mode;
  }
  
  static int read_cfl_alphas(FRAME_CONTEXT *const ec_ctx, aom_reader *r,
                             int *signs_out) {
    const int joint_sign =
        aom_read_symbol(r, ec_ctx->cfl_sign_cdf, CFL_JOINT_SIGNS, "cfl:signs");
    int idx = 0;
    // Magnitudes are only coded for nonzero values
    if (CFL_SIGN_U(joint_sign) != CFL_SIGN_ZERO) {
      aom_cdf_prob *cdf_u = ec_ctx->cfl_alpha_cdf[CFL_CONTEXT_U(joint_sign)];
      idx = aom_read_symbol(r, cdf_u, CFL_ALPHABET_SIZE, "cfl:alpha_u")
            << CFL_ALPHABET_SIZE_LOG2;
    }
    if (CFL_SIGN_V(joint_sign) != CFL_SIGN_ZERO) {
      aom_cdf_prob *cdf_v = ec_ctx->cfl_alpha_cdf[CFL_CONTEXT_V(joint_sign)];
      idx += aom_read_symbol(r, cdf_v, CFL_ALPHABET_SIZE, "cfl:alpha_v");
    }
    *signs_out = joint_sign;
    return idx;
  }
  
  static INTERINTRA_MODE read_interintra_mode(MACROBLOCKD *xd, aom_reader *r,
                                              int size_group) {
    const INTERINTRA_MODE ii_mode = (INTERINTRA_MODE)aom_read_symbol(
        r, xd->tile_ctx->interintra_mode_cdf[size_group], INTERINTRA_MODES,
        ACCT_STR);
    return ii_mode;
  }
  
  static PREDICTION_MODE read_inter_mode(FRAME_CONTEXT *ec_ctx, aom_reader *r,
                                         int16_t ctx) {
    int16_t mode_ctx = ctx & NEWMV_CTX_MASK;
    int is_newmv, is_zeromv, is_refmv;
    is_newmv = aom_read_symbol(r, ec_ctx->newmv_cdf[mode_ctx], 2, ACCT_STR) == 0;
    if (is_newmv) return NEWMV;
  
    mode_ctx = (ctx >> GLOBALMV_OFFSET) & GLOBALMV_CTX_MASK;
    is_zeromv =
        aom_read_symbol(r, ec_ctx->zeromv_cdf[mode_ctx], 2, ACCT_STR) == 0;
    if (is_zeromv) return GLOBALMV;
  
    mode_ctx = (ctx >> REFMV_OFFSET) & REFMV_CTX_MASK;
    is_refmv = aom_read_symbol(r, ec_ctx->refmv_cdf[mode_ctx], 2, ACCT_STR) == 0;
    if (is_refmv)
      return NEARESTMV;
    else
      return NEARMV;
  }
  
  static void read_drl_idx(FRAME_CONTEXT *ec_ctx, MACROBLOCKD *xd,
                           MB_MODE_INFO *mbmi, aom_reader *r) {
    uint8_t ref_frame_type = av1_ref_frame_type(mbmi->ref_frame);
    mbmi->ref_mv_idx = 0;
    if (mbmi->mode == NEWMV || mbmi->mode == NEW_NEWMV) {
      for (int idx = 0; idx < 2; ++idx) {
        if (xd->ref_mv_count[ref_frame_type] > idx + 1) {
          uint8_t drl_ctx = av1_drl_ctx(xd->ref_mv_stack[ref_frame_type], idx);
          int drl_idx = aom_read_symbol(r, ec_ctx->drl_cdf[drl_ctx], 2, ACCT_STR);
          mbmi->ref_mv_idx = idx + drl_idx;
          if (!drl_idx) return;
        }
      }
    }
    if (have_nearmv_in_inter_mode(mbmi->mode)) {
      // Offset the NEARESTMV mode.
      // TODO(jingning): Unify the two syntax decoding loops after the NEARESTMV
      // mode is factored in.
      for (int idx = 1; idx < 3; ++idx) {
        if (xd->ref_mv_count[ref_frame_type] > idx + 1) {
          uint8_t drl_ctx = av1_drl_ctx(xd->ref_mv_stack[ref_frame_type], idx);
          int drl_idx = aom_read_symbol(r, ec_ctx->drl_cdf[drl_ctx], 2, ACCT_STR);
          mbmi->ref_mv_idx = idx + drl_idx - 1;
          if (!drl_idx) return;
        }
      }
    }
  }
  
  static MOTION_MODE read_motion_mode(AV1_COMMON *cm, MACROBLOCKD *xd,
                                      MB_MODE_INFO *mbmi, aom_reader *r) {
    if (cm->switchable_motion_mode == 0) return SIMPLE_TRANSLATION;
    if (mbmi->skip_mode) return SIMPLE_TRANSLATION;
  
    const MOTION_MODE last_motion_mode_allowed =
        motion_mode_allowed(xd->global_motion, xd, mbmi, cm->allow_warped_motion);
    int motion_mode;
  
    if (last_motion_mode_allowed == SIMPLE_TRANSLATION) return SIMPLE_TRANSLATION;
  
    if (last_motion_mode_allowed == OBMC_CAUSAL) {
      motion_mode =
          aom_read_symbol(r, xd->tile_ctx->obmc_cdf[mbmi->sb_type], 2, ACCT_STR);
      return (MOTION_MODE)(SIMPLE_TRANSLATION + motion_mode);
    } else {
      motion_mode =
          aom_read_symbol(r, xd->tile_ctx->motion_mode_cdf[mbmi->sb_type],
                          MOTION_MODES, ACCT_STR);
      return (MOTION_MODE)(SIMPLE_TRANSLATION + motion_mode);
    }
  }
  
  static PREDICTION_MODE read_inter_compound_mode(MACROBLOCKD *xd, aom_reader *r,
                                                  int16_t ctx) {
    const int mode =
        aom_read_symbol(r, xd->tile_ctx->inter_compound_mode_cdf[ctx],
                        INTER_COMPOUND_MODES, ACCT_STR);
    assert(is_inter_compound_mode(NEAREST_NEARESTMV + mode));
    return NEAREST_NEARESTMV + mode;
  }
  
  int av1_neg_deinterleave(int diff, int ref, int max) {
    if (!ref) return diff;
    if (ref >= (max - 1)) return max - diff - 1;
    if (2 * ref < max) {
      if (diff <= 2 * ref) {
        if (diff & 1)
          return ref + ((diff + 1) >> 1);
        else
          return ref - (diff >> 1);
      }
      return diff;
    } else {
      if (diff <= 2 * (max - ref - 1)) {
        if (diff & 1)
          return ref + ((diff + 1) >> 1);
        else
          return ref - (diff >> 1);
      }
      return max - (diff + 1);
    }
  }
  
  static int read_segment_id(AV1_COMMON *const cm, const MACROBLOCKD *const xd,
                             int mi_row, int mi_col, aom_reader *r, int skip) {
    int cdf_num;
    const int pred = av1_get_spatial_seg_pred(cm, xd, mi_row, mi_col, &cdf_num);
    if (skip) return pred;
  
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
    struct segmentation *const seg = &cm->seg;
    struct segmentation_probs *const segp = &ec_ctx->seg;
    aom_cdf_prob *pred_cdf = segp->spatial_pred_seg_cdf[cdf_num];
    const int coded_id = aom_read_symbol(r, pred_cdf, MAX_SEGMENTS, ACCT_STR);
    const int segment_id =
        av1_neg_deinterleave(coded_id, pred, seg->last_active_segid + 1);
  
    if (segment_id < 0 || segment_id > seg->last_active_segid) {
      aom_internal_error(xd->error_info, AOM_CODEC_CORRUPT_FRAME,
                         "Corrupted segment_ids");
    }
    return segment_id;
  }
  
  static int dec_get_segment_id(const AV1_COMMON *cm, const uint8_t *segment_ids,
                                int mi_offset, int x_mis, int y_mis) {
    int segment_id = INT_MAX;
  
    for (int y = 0; y < y_mis; y++)
      for (int x = 0; x < x_mis; x++)
        segment_id =
            AOMMIN(segment_id, segment_ids[mi_offset + y * cm->mi_cols + x]);
  
    assert(segment_id >= 0 && segment_id < MAX_SEGMENTS);
    return segment_id;
  }
  
  static void set_segment_id(AV1_COMMON *cm, int mi_offset, int x_mis, int y_mis,
                             int segment_id) {
    assert(segment_id >= 0 && segment_id < MAX_SEGMENTS);
  
    for (int y = 0; y < y_mis; y++)
      for (int x = 0; x < x_mis; x++)
        cm->current_frame_seg_map[mi_offset + y * cm->mi_cols + x] = segment_id;
  }
  
  static int read_intra_segment_id(AV1_COMMON *const cm,
                                   const MACROBLOCKD *const xd, int mi_row,
                                   int mi_col, int bsize, aom_reader *r,
                                   int skip) {
    struct segmentation *const seg = &cm->seg;
    if (!seg->enabled) return 0;  // Default for disabled segmentation
  
    assert(seg->update_map && !seg->temporal_update);
  
    const int mi_offset = mi_row * cm->mi_cols + mi_col;
    const int bw = mi_size_wide[bsize];
    const int bh = mi_size_high[bsize];
    const int x_mis = AOMMIN(cm->mi_cols - mi_col, bw);
    const int y_mis = AOMMIN(cm->mi_rows - mi_row, bh);
    const int segment_id = read_segment_id(cm, xd, mi_row, mi_col, r, skip);
    set_segment_id(cm, mi_offset, x_mis, y_mis, segment_id);
    return segment_id;
  }
  
  static void copy_segment_id(const AV1_COMMON *cm,
                              const uint8_t *last_segment_ids,
                              uint8_t *current_segment_ids, int mi_offset,
                              int x_mis, int y_mis) {
    for (int y = 0; y < y_mis; y++)
      for (int x = 0; x < x_mis; x++)
        current_segment_ids[mi_offset + y * cm->mi_cols + x] =
            last_segment_ids ? last_segment_ids[mi_offset + y * cm->mi_cols + x]
                             : 0;
  }
  
  static int get_predicted_segment_id(AV1_COMMON *const cm, int mi_offset,
                                      int x_mis, int y_mis) {
    return cm->last_frame_seg_map ? dec_get_segment_id(cm, cm->last_frame_seg_map,
                                                       mi_offset, x_mis, y_mis)
                                  : 0;
  }
  
  static int read_inter_segment_id(AV1_COMMON *const cm, MACROBLOCKD *const xd,
                                   int mi_row, int mi_col, int preskip,
                                   aom_reader *r) {
    struct segmentation *const seg = &cm->seg;
    MB_MODE_INFO *const mbmi = xd->mi[0];
    const int mi_offset = mi_row * cm->mi_cols + mi_col;
    const int bw = mi_size_wide[mbmi->sb_type];
    const int bh = mi_size_high[mbmi->sb_type];
  
    // TODO(slavarnway): move x_mis, y_mis into xd ?????
    const int x_mis = AOMMIN(cm->mi_cols - mi_col, bw);
    const int y_mis = AOMMIN(cm->mi_rows - mi_row, bh);
  
    if (!seg->enabled) return 0;  // Default for disabled segmentation
  
    if (!seg->update_map) {
      copy_segment_id(cm, cm->last_frame_seg_map, cm->current_frame_seg_map,
                      mi_offset, x_mis, y_mis);
      return get_predicted_segment_id(cm, mi_offset, x_mis, y_mis);
    }
  
    int segment_id;
    if (preskip) {
      if (!seg->segid_preskip) return 0;
    } else {
      if (seg->segid_preskip) return mbmi->segment_id;
      if (mbmi->skip) {
        if (seg->temporal_update) {
          mbmi->seg_id_predicted = 0;
        }
        segment_id = read_segment_id(cm, xd, mi_row, mi_col, r, 1);
        set_segment_id(cm, mi_offset, x_mis, y_mis, segment_id);
        return segment_id;
      }
    }
  
    if (seg->temporal_update) {
      const int ctx = av1_get_pred_context_seg_id(xd);
      FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
      struct segmentation_probs *const segp = &ec_ctx->seg;
      aom_cdf_prob *pred_cdf = segp->pred_cdf[ctx];
      mbmi->seg_id_predicted = aom_read_symbol(r, pred_cdf, 2, ACCT_STR);
      if (mbmi->seg_id_predicted) {
        segment_id = get_predicted_segment_id(cm, mi_offset, x_mis, y_mis);
      } else {
        segment_id = read_segment_id(cm, xd, mi_row, mi_col, r, 0);
      }
    } else {
      segment_id = read_segment_id(cm, xd, mi_row, mi_col, r, 0);
    }
    set_segment_id(cm, mi_offset, x_mis, y_mis, segment_id);
    return segment_id;
  }
  
  static int read_skip_mode(AV1_COMMON *cm, const MACROBLOCKD *xd, int segment_id,
                            aom_reader *r) {
    if (!cm->skip_mode_flag) return 0;
  
    if (segfeature_active(&cm->seg, segment_id, SEG_LVL_SKIP)) {
      return 0;
    }
  
    if (!is_comp_ref_allowed(xd->mi[0]->sb_type)) return 0;
  
    if (segfeature_active(&cm->seg, segment_id, SEG_LVL_REF_FRAME) ||
        segfeature_active(&cm->seg, segment_id, SEG_LVL_GLOBALMV)) {
      // These features imply single-reference mode, while skip mode implies
      // compound reference. Hence, the two are mutually exclusive.
      // In other words, skip_mode is implicitly 0 here.
      return 0;
    }
  
    const int ctx = av1_get_skip_mode_context(xd);
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
    const int skip_mode =
        aom_read_symbol(r, ec_ctx->skip_mode_cdfs[ctx], 2, ACCT_STR);
    return skip_mode;
  }
  
  static int read_skip(AV1_COMMON *cm, const MACROBLOCKD *xd, int segment_id,
                       aom_reader *r) {
    if (segfeature_active(&cm->seg, segment_id, SEG_LVL_SKIP)) {
      return 1;
    } else {
      const int ctx = av1_get_skip_context(xd);
      FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
      const int skip = aom_read_symbol(r, ec_ctx->skip_cdfs[ctx], 2, ACCT_STR);
      return skip;
    }
  }
  
  // Merge the sorted list of cached colors(cached_colors[0...n_cached_colors-1])
  // and the sorted list of transmitted colors(colors[n_cached_colors...n-1]) into
  // one single sorted list(colors[...]).
  static void merge_colors(uint16_t *colors, uint16_t *cached_colors,
                           int n_colors, int n_cached_colors) {
    if (n_cached_colors == 0) return;
    int cache_idx = 0, trans_idx = n_cached_colors;
    for (int i = 0; i < n_colors; ++i) {
      if (cache_idx < n_cached_colors &&
          (trans_idx >= n_colors ||
           cached_colors[cache_idx] <= colors[trans_idx])) {
        colors[i] = cached_colors[cache_idx++];
      } else {
        assert(trans_idx < n_colors);
        colors[i] = colors[trans_idx++];
      }
    }
  }
  
  static void read_palette_colors_y(MACROBLOCKD *const xd, int bit_depth,
                                    PALETTE_MODE_INFO *const pmi, aom_reader *r) {
    uint16_t color_cache[2 * PALETTE_MAX_SIZE];
    uint16_t cached_colors[PALETTE_MAX_SIZE];
    const int n_cache = av1_get_palette_cache(xd, 0, color_cache);
    const int n = pmi->palette_size[0];
    int idx = 0;
    for (int i = 0; i < n_cache && idx < n; ++i)
      if (aom_read_bit(r, ACCT_STR)) cached_colors[idx++] = color_cache[i];
    if (idx < n) {
      const int n_cached_colors = idx;
      pmi->palette_colors[idx++] = aom_read_literal(r, bit_depth, ACCT_STR);
      if (idx < n) {
        const int min_bits = bit_depth - 3;
        int bits = min_bits + aom_read_literal(r, 2, ACCT_STR);
        int range = (1 << bit_depth) - pmi->palette_colors[idx - 1] - 1;
        for (; idx < n; ++idx) {
          assert(range >= 0);
          const int delta = aom_read_literal(r, bits, ACCT_STR) + 1;
          pmi->palette_colors[idx] = clamp(pmi->palette_colors[idx - 1] + delta,
                                           0, (1 << bit_depth) - 1);
          range -= (pmi->palette_colors[idx] - pmi->palette_colors[idx - 1]);
          bits = AOMMIN(bits, av1_ceil_log2(range));
        }
      }
      merge_colors(pmi->palette_colors, cached_colors, n, n_cached_colors);
    } else {
      memcpy(pmi->palette_colors, cached_colors, n * sizeof(cached_colors[0]));
    }
  }
  
  static void read_palette_colors_uv(MACROBLOCKD *const xd, int bit_depth,
                                     PALETTE_MODE_INFO *const pmi,
                                     aom_reader *r) {
    const int n = pmi->palette_size[1];
    // U channel colors.
    uint16_t color_cache[2 * PALETTE_MAX_SIZE];
    uint16_t cached_colors[PALETTE_MAX_SIZE];
    const int n_cache = av1_get_palette_cache(xd, 1, color_cache);
    int idx = 0;
    for (int i = 0; i < n_cache && idx < n; ++i)
      if (aom_read_bit(r, ACCT_STR)) cached_colors[idx++] = color_cache[i];
    if (idx < n) {
      const int n_cached_colors = idx;
      idx += PALETTE_MAX_SIZE;
      pmi->palette_colors[idx++] = aom_read_literal(r, bit_depth, ACCT_STR);
      if (idx < PALETTE_MAX_SIZE + n) {
        const int min_bits = bit_depth - 3;
        int bits = min_bits + aom_read_literal(r, 2, ACCT_STR);
        int range = (1 << bit_depth) - pmi->palette_colors[idx - 1];
        for (; idx < PALETTE_MAX_SIZE + n; ++idx) {
          assert(range >= 0);
          const int delta = aom_read_literal(r, bits, ACCT_STR);
          pmi->palette_colors[idx] = clamp(pmi->palette_colors[idx - 1] + delta,
                                           0, (1 << bit_depth) - 1);
          range -= (pmi->palette_colors[idx] - pmi->palette_colors[idx - 1]);
          bits = AOMMIN(bits, av1_ceil_log2(range));
        }
      }
      merge_colors(pmi->palette_colors + PALETTE_MAX_SIZE, cached_colors, n,
                   n_cached_colors);
    } else {
      memcpy(pmi->palette_colors + PALETTE_MAX_SIZE, cached_colors,
             n * sizeof(cached_colors[0]));
    }
  
    // V channel colors.
    if (aom_read_bit(r, ACCT_STR)) {  // Delta encoding.
      const int min_bits_v = bit_depth - 4;
      const int max_val = 1 << bit_depth;
      int bits = min_bits_v + aom_read_literal(r, 2, ACCT_STR);
      pmi->palette_colors[2 * PALETTE_MAX_SIZE] =
          aom_read_literal(r, bit_depth, ACCT_STR);
      for (int i = 1; i < n; ++i) {
        int delta = aom_read_literal(r, bits, ACCT_STR);
        if (delta && aom_read_bit(r, ACCT_STR)) delta = -delta;
        int val = (int)pmi->palette_colors[2 * PALETTE_MAX_SIZE + i - 1] + delta;
        if (val < 0) val += max_val;
        if (val >= max_val) val -= max_val;
        pmi->palette_colors[2 * PALETTE_MAX_SIZE + i] = val;
      }
    } else {
      for (int i = 0; i < n; ++i) {
        pmi->palette_colors[2 * PALETTE_MAX_SIZE + i] =
            aom_read_literal(r, bit_depth, ACCT_STR);
      }
    }
  }
  
  static void read_palette_mode_info(AV1_COMMON *const cm, MACROBLOCKD *const xd,
                                     int mi_row, int mi_col, aom_reader *r) {
    const int num_planes = av1_num_planes(cm);
    MB_MODE_INFO *const mbmi = xd->mi[0];
    const BLOCK_SIZE bsize = mbmi->sb_type;
    assert(av1_allow_palette(cm->allow_screen_content_tools, bsize));
    PALETTE_MODE_INFO *const pmi = &mbmi->palette_mode_info;
    const int bsize_ctx = av1_get_palette_bsize_ctx(bsize);
  
    if (mbmi->mode == DC_PRED) {
      const int palette_mode_ctx = av1_get_palette_mode_ctx(xd);
      const int modev = aom_read_symbol(
          r, xd->tile_ctx->palette_y_mode_cdf[bsize_ctx][palette_mode_ctx], 2,
          ACCT_STR);
      if (modev) {
        pmi->palette_size[0] =
            aom_read_symbol(r, xd->tile_ctx->palette_y_size_cdf[bsize_ctx],
                            PALETTE_SIZES, ACCT_STR) +
            2;
        read_palette_colors_y(xd, cm->bit_depth, pmi, r);
      }
    }
    if (num_planes > 1 && mbmi->uv_mode == UV_DC_PRED &&
        is_chroma_reference(mi_row, mi_col, bsize, xd->plane[1].subsampling_x,
                            xd->plane[1].subsampling_y)) {
      const int palette_uv_mode_ctx = (pmi->palette_size[0] > 0);
      const int modev = aom_read_symbol(
          r, xd->tile_ctx->palette_uv_mode_cdf[palette_uv_mode_ctx], 2, ACCT_STR);
      if (modev) {
        pmi->palette_size[1] =
            aom_read_symbol(r, xd->tile_ctx->palette_uv_size_cdf[bsize_ctx],
                            PALETTE_SIZES, ACCT_STR) +
            2;
        read_palette_colors_uv(xd, cm->bit_depth, pmi, r);
      }
    }
  }
  
  static int read_angle_delta(aom_reader *r, aom_cdf_prob *cdf) {
    const int sym = aom_read_symbol(r, cdf, 2 * MAX_ANGLE_DELTA + 1, ACCT_STR);
    return sym - MAX_ANGLE_DELTA;
  }
  
  static void read_filter_intra_mode_info(const AV1_COMMON *const cm,
                                          MACROBLOCKD *const xd, aom_reader *r) {
    MB_MODE_INFO *const mbmi = xd->mi[0];
    FILTER_INTRA_MODE_INFO *filter_intra_mode_info =
        &mbmi->filter_intra_mode_info;
  
    if (av1_filter_intra_allowed(cm, mbmi)) {
      filter_intra_mode_info->use_filter_intra = aom_read_symbol(
          r, xd->tile_ctx->filter_intra_cdfs[mbmi->sb_type], 2, ACCT_STR);
      if (filter_intra_mode_info->use_filter_intra) {
        filter_intra_mode_info->filter_intra_mode = aom_read_symbol(
            r, xd->tile_ctx->filter_intra_mode_cdf, FILTER_INTRA_MODES, ACCT_STR);
      }
    } else {
      filter_intra_mode_info->use_filter_intra = 0;
    }
  }
  
  void av1_read_tx_type(const AV1_COMMON *const cm, MACROBLOCKD *xd, int blk_row,
                        int blk_col, TX_SIZE tx_size, aom_reader *r) {
    MB_MODE_INFO *mbmi = xd->mi[0];
    const int inter_block = is_inter_block(mbmi);
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  
    const int txk_type_idx =
        av1_get_txk_type_index(mbmi->sb_type, blk_row, blk_col);
    TX_TYPE *tx_type = &mbmi->txk_type[txk_type_idx];
  
    const TX_SIZE square_tx_size = txsize_sqr_map[tx_size];
    if (get_ext_tx_types(tx_size, inter_block, cm->reduced_tx_set_used) > 1 &&
        ((!cm->seg.enabled && cm->base_qindex > 0) ||
         (cm->seg.enabled && xd->qindex[mbmi->segment_id] > 0)) &&
        !mbmi->skip &&
        !segfeature_active(&cm->seg, mbmi->segment_id, SEG_LVL_SKIP)) {
      const TxSetType tx_set_type =
          av1_get_ext_tx_set_type(tx_size, inter_block, cm->reduced_tx_set_used);
      const int eset =
          get_ext_tx_set(tx_size, inter_block, cm->reduced_tx_set_used);
      // eset == 0 should correspond to a set with only DCT_DCT and
      // there is no need to read the tx_type
      assert(eset != 0);
  
      if (inter_block) {
        *tx_type = av1_ext_tx_inv[tx_set_type][aom_read_symbol(
            r, ec_ctx->inter_ext_tx_cdf[eset][square_tx_size],
            av1_num_ext_tx_set[tx_set_type], ACCT_STR)];
      } else {
        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;
        *tx_type = av1_ext_tx_inv[tx_set_type][aom_read_symbol(
            r, ec_ctx->intra_ext_tx_cdf[eset][square_tx_size][intra_dir],
            av1_num_ext_tx_set[tx_set_type], ACCT_STR)];
      }
    } else {
      *tx_type = DCT_DCT;
    }
  }
  
  static INLINE void read_mv(aom_reader *r, MV *mv, const MV *ref,
                             nmv_context *ctx, MvSubpelPrecision precision);
  
  static INLINE int is_mv_valid(const MV *mv);
  
  static INLINE int assign_dv(AV1_COMMON *cm, MACROBLOCKD *xd, int_mv *mv,
                              const int_mv *ref_mv, int mi_row, int mi_col,
                              BLOCK_SIZE bsize, aom_reader *r) {
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
    read_mv(r, &mv->as_mv, &ref_mv->as_mv, &ec_ctx->ndvc, MV_SUBPEL_NONE);
    // DV should not have sub-pel.
    assert((mv->as_mv.col & 7) == 0);
    assert((mv->as_mv.row & 7) == 0);
    mv->as_mv.col = (mv->as_mv.col >> 3) * 8;
    mv->as_mv.row = (mv->as_mv.row >> 3) * 8;
    int valid = is_mv_valid(&mv->as_mv) &&
                av1_is_dv_valid(mv->as_mv, cm, xd, mi_row, mi_col, bsize,
                                cm->seq_params.mib_size_log2);
    return valid;
  }
  
  static void read_intrabc_info(AV1_COMMON *const cm, MACROBLOCKD *const xd,
                                int mi_row, int mi_col, aom_reader *r) {
    MB_MODE_INFO *const mbmi = xd->mi[0];
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
    mbmi->use_intrabc = aom_read_symbol(r, ec_ctx->intrabc_cdf, 2, ACCT_STR);
    if (mbmi->use_intrabc) {
      BLOCK_SIZE bsize = mbmi->sb_type;
      mbmi->mode = DC_PRED;
      mbmi->uv_mode = UV_DC_PRED;
      mbmi->interp_filters = av1_broadcast_interp_filter(BILINEAR);
      mbmi->motion_mode = SIMPLE_TRANSLATION;
  
      int16_t inter_mode_ctx[MODE_CTX_REF_FRAMES];
      int_mv ref_mvs[INTRA_FRAME + 1][MAX_MV_REF_CANDIDATES];
      int_mv global_mvs[REF_FRAMES];
  
      av1_find_mv_refs(cm, xd, mbmi, INTRA_FRAME, xd->ref_mv_count,
                       xd->ref_mv_stack, ref_mvs, global_mvs, mi_row, mi_col,
                       inter_mode_ctx);
  
      int_mv nearestmv, nearmv;
  
      av1_find_best_ref_mvs(0, ref_mvs[INTRA_FRAME], &nearestmv, &nearmv, 0);
      int_mv dv_ref = nearestmv.as_int == 0 ? nearmv : nearestmv;
      if (dv_ref.as_int == 0)
        av1_find_ref_dv(&dv_ref, &xd->tile, cm->seq_params.mib_size, mi_row,
                        mi_col);
      // Ref DV should not have sub-pel.
      int valid_dv = (dv_ref.as_mv.col & 7) == 0 && (dv_ref.as_mv.row & 7) == 0;
      dv_ref.as_mv.col = (dv_ref.as_mv.col >> 3) * 8;
      dv_ref.as_mv.row = (dv_ref.as_mv.row >> 3) * 8;
      valid_dv = valid_dv && assign_dv(cm, xd, &mbmi->mv[0], &dv_ref, mi_row,
                                       mi_col, bsize, r);
      if (!valid_dv) {
        // Intra bc motion vectors are not valid - signal corrupt frame
        aom_merge_corrupted_flag(&xd->corrupted, 1);
      }
    }
  }
  
  static void read_intra_frame_mode_info(AV1_COMMON *const cm,
                                         MACROBLOCKD *const xd, int mi_row,
                                         int mi_col, aom_reader *r) {
    MB_MODE_INFO *const mbmi = xd->mi[0];
    const MB_MODE_INFO *above_mi = xd->above_mbmi;
    const MB_MODE_INFO *left_mi = xd->left_mbmi;
    const BLOCK_SIZE bsize = mbmi->sb_type;
    struct segmentation *const seg = &cm->seg;
  
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  
    if (seg->segid_preskip)
      mbmi->segment_id =
          read_intra_segment_id(cm, xd, mi_row, mi_col, bsize, r, 0);
  
    mbmi->skip = read_skip(cm, xd, mbmi->segment_id, r);
  
    if (!seg->segid_preskip)
      mbmi->segment_id =
          read_intra_segment_id(cm, xd, mi_row, mi_col, bsize, r, mbmi->skip);
  
    read_cdef(cm, r, xd, mi_col, mi_row);
  
    if (cm->delta_q_present_flag) {
      xd->current_qindex +=
          read_delta_qindex(cm, xd, r, mbmi, mi_col, mi_row) * cm->delta_q_res;
      /* Normative: Clamp to [1,MAXQ] to not interfere with lossless mode */
      xd->current_qindex = clamp(xd->current_qindex, 1, MAXQ);
      if (cm->delta_lf_present_flag) {
        if (cm->delta_lf_multi) {
          const int frame_lf_count =
              av1_num_planes(cm) > 1 ? FRAME_LF_COUNT : FRAME_LF_COUNT - 2;
          for (int lf_id = 0; lf_id < frame_lf_count; ++lf_id) {
            const int tmp_lvl =
                xd->delta_lf[lf_id] +
                read_delta_lflevel(cm, xd, r, lf_id, mbmi, mi_col, mi_row) *
                    cm->delta_lf_res;
            mbmi->delta_lf[lf_id] = xd->delta_lf[lf_id] =
                clamp(tmp_lvl, -MAX_LOOP_FILTER, MAX_LOOP_FILTER);
          }
        } else {
          const int tmp_lvl =
              xd->delta_lf_from_base +
              read_delta_lflevel(cm, xd, r, -1, mbmi, mi_col, mi_row) *
                  cm->delta_lf_res;
          mbmi->delta_lf_from_base = xd->delta_lf_from_base =
              clamp(tmp_lvl, -MAX_LOOP_FILTER, MAX_LOOP_FILTER);
        }
      }
    }
  
    mbmi->current_qindex = xd->current_qindex;
  
    mbmi->ref_frame[0] = INTRA_FRAME;
    mbmi->ref_frame[1] = NONE_FRAME;
    mbmi->palette_mode_info.palette_size[0] = 0;
    mbmi->palette_mode_info.palette_size[1] = 0;
    mbmi->filter_intra_mode_info.use_filter_intra = 0;
  
    xd->above_txfm_context = cm->above_txfm_context[xd->tile.tile_row] + mi_col;
    xd->left_txfm_context =
        xd->left_txfm_context_buffer + (mi_row & MAX_MIB_MASK);
  
    if (av1_allow_intrabc(cm)) {
      read_intrabc_info(cm, xd, mi_row, mi_col, r);
      if (is_intrabc_block(mbmi)) return;
    }
  
    mbmi->mode = read_intra_mode(r, get_y_mode_cdf(ec_ctx, above_mi, left_mi));
  
    const int use_angle_delta = av1_use_angle_delta(bsize);
    mbmi->angle_delta[PLANE_TYPE_Y] =
        (use_angle_delta && av1_is_directional_mode(mbmi->mode))
            ? read_angle_delta(r, ec_ctx->angle_delta_cdf[mbmi->mode - V_PRED])
            : 0;
  
    if (!cm->seq_params.monochrome &&
        is_chroma_reference(mi_row, mi_col, bsize, xd->plane[1].subsampling_x,
                            xd->plane[1].subsampling_y)) {
      xd->cfl.is_chroma_reference = 1;
      mbmi->uv_mode =
          read_intra_mode_uv(ec_ctx, r, is_cfl_allowed(xd), mbmi->mode);
      if (mbmi->uv_mode == UV_CFL_PRED) {
        mbmi->cfl_alpha_idx = read_cfl_alphas(ec_ctx, r, &mbmi->cfl_alpha_signs);
      }
      mbmi->angle_delta[PLANE_TYPE_UV] =
          (use_angle_delta && av1_is_directional_mode(get_uv_mode(mbmi->uv_mode)))
              ? read_angle_delta(r,
                                 ec_ctx->angle_delta_cdf[mbmi->uv_mode - V_PRED])
              : 0;
    } else {
      // Avoid decoding angle_info if there is is no chroma prediction
      mbmi->uv_mode = UV_DC_PRED;
      xd->cfl.is_chroma_reference = 0;
    }
    xd->cfl.store_y = store_cfl_required(cm, xd);
  
    if (av1_allow_palette(cm->allow_screen_content_tools, bsize))
      read_palette_mode_info(cm, xd, mi_row, mi_col, r);
  
    read_filter_intra_mode_info(cm, xd, r);
  }
  
  static int read_mv_component(aom_reader *r, nmv_component *mvcomp,
                               int use_subpel, int usehp) {
    int mag, d, fr, hp;
    const int sign = aom_read_symbol(r, mvcomp->sign_cdf, 2, ACCT_STR);
    const int mv_class =
        aom_read_symbol(r, mvcomp->classes_cdf, MV_CLASSES, ACCT_STR);
    const int class0 = mv_class == MV_CLASS_0;
  
    // Integer part
    if (class0) {
      d = aom_read_symbol(r, mvcomp->class0_cdf, CLASS0_SIZE, ACCT_STR);
      mag = 0;
    } else {
      const int n = mv_class + CLASS0_BITS - 1;  // number of bits
      d = 0;
      for (int i = 0; i < n; ++i)
        d |= aom_read_symbol(r, mvcomp->bits_cdf[i], 2, ACCT_STR) << i;
      mag = CLASS0_SIZE << (mv_class + 2);
    }
  
    if (use_subpel) {
      // Fractional part
      fr = aom_read_symbol(r, class0 ? mvcomp->class0_fp_cdf[d] : mvcomp->fp_cdf,
                           MV_FP_SIZE, ACCT_STR);
  
      // High precision part (if hp is not used, the default value of the hp is 1)
      hp = usehp ? aom_read_symbol(
                       r, class0 ? mvcomp->class0_hp_cdf : mvcomp->hp_cdf, 2,
                       ACCT_STR)
                 : 1;
    } else {
      fr = 3;
      hp = 1;
    }
  
    // Result
    mag += ((d << 3) | (fr << 1) | hp) + 1;
    return sign ? -mag : mag;
  }
  
  static INLINE void read_mv(aom_reader *r, MV *mv, const MV *ref,
                             nmv_context *ctx, MvSubpelPrecision precision) {
    MV diff = kZeroMv;
    const MV_JOINT_TYPE joint_type =
        (MV_JOINT_TYPE)aom_read_symbol(r, ctx->joints_cdf, MV_JOINTS, ACCT_STR);
  
    if (mv_joint_vertical(joint_type))
      diff.row = read_mv_component(r, &ctx->comps[0], precision > MV_SUBPEL_NONE,
                                   precision > MV_SUBPEL_LOW_PRECISION);
  
    if (mv_joint_horizontal(joint_type))
      diff.col = read_mv_component(r, &ctx->comps[1], precision > MV_SUBPEL_NONE,
                                   precision > MV_SUBPEL_LOW_PRECISION);
  
    mv->row = ref->row + diff.row;
    mv->col = ref->col + diff.col;
  }
  
  static REFERENCE_MODE read_block_reference_mode(AV1_COMMON *cm,
                                                  const MACROBLOCKD *xd,
                                                  aom_reader *r) {
    if (!is_comp_ref_allowed(xd->mi[0]->sb_type)) return SINGLE_REFERENCE;
    if (cm->reference_mode == REFERENCE_MODE_SELECT) {
      const int ctx = av1_get_reference_mode_context(xd);
      const REFERENCE_MODE mode = (REFERENCE_MODE)aom_read_symbol(
          r, xd->tile_ctx->comp_inter_cdf[ctx], 2, ACCT_STR);
      return mode;  // SINGLE_REFERENCE or COMPOUND_REFERENCE
    } else {
      assert(cm->reference_mode == SINGLE_REFERENCE);
      return cm->reference_mode;
    }
  }
  
  #define READ_REF_BIT(pname) \
    aom_read_symbol(r, av1_get_pred_cdf_##pname(xd), 2, ACCT_STR)
  
  static COMP_REFERENCE_TYPE read_comp_reference_type(const MACROBLOCKD *xd,
                                                      aom_reader *r) {
    const int ctx = av1_get_comp_reference_type_context(xd);
    const COMP_REFERENCE_TYPE comp_ref_type =
        (COMP_REFERENCE_TYPE)aom_read_symbol(
            r, xd->tile_ctx->comp_ref_type_cdf[ctx], 2, ACCT_STR);
    return comp_ref_type;  // UNIDIR_COMP_REFERENCE or BIDIR_COMP_REFERENCE
  }
  
  static void set_ref_frames_for_skip_mode(AV1_COMMON *const cm,
                                           MV_REFERENCE_FRAME ref_frame[2]) {
    ref_frame[0] = LAST_FRAME + cm->ref_frame_idx_0;
    ref_frame[1] = LAST_FRAME + cm->ref_frame_idx_1;
  }
  
  // Read the referncence frame
  static void read_ref_frames(AV1_COMMON *const cm, MACROBLOCKD *const xd,
                              aom_reader *r, int segment_id,
                              MV_REFERENCE_FRAME ref_frame[2]) {
    if (xd->mi[0]->skip_mode) {
      set_ref_frames_for_skip_mode(cm, ref_frame);
      return;
    }
  
    if (segfeature_active(&cm->seg, segment_id, SEG_LVL_REF_FRAME)) {
      ref_frame[0] = (MV_REFERENCE_FRAME)get_segdata(&cm->seg, segment_id,
                                                     SEG_LVL_REF_FRAME);
      ref_frame[1] = NONE_FRAME;
    } else if (segfeature_active(&cm->seg, segment_id, SEG_LVL_SKIP) ||
               segfeature_active(&cm->seg, segment_id, SEG_LVL_GLOBALMV)) {
      ref_frame[0] = LAST_FRAME;
      ref_frame[1] = NONE_FRAME;
    } else {
      const REFERENCE_MODE mode = read_block_reference_mode(cm, xd, r);
  
      if (mode == COMPOUND_REFERENCE) {
        const COMP_REFERENCE_TYPE comp_ref_type = read_comp_reference_type(xd, r);
  
        if (comp_ref_type == UNIDIR_COMP_REFERENCE) {
          const int bit = READ_REF_BIT(uni_comp_ref_p);
          if (bit) {
            ref_frame[0] = BWDREF_FRAME;
            ref_frame[1] = ALTREF_FRAME;
          } else {
            const int bit1 = READ_REF_BIT(uni_comp_ref_p1);
            if (bit1) {
              const int bit2 = READ_REF_BIT(uni_comp_ref_p2);
              if (bit2) {
                ref_frame[0] = LAST_FRAME;
                ref_frame[1] = GOLDEN_FRAME;
              } else {
                ref_frame[0] = LAST_FRAME;
                ref_frame[1] = LAST3_FRAME;
              }
            } else {
              ref_frame[0] = LAST_FRAME;
              ref_frame[1] = LAST2_FRAME;
            }
          }
  
          return;
        }
  
        assert(comp_ref_type == BIDIR_COMP_REFERENCE);
  
        const int idx = 1;
        const int bit = READ_REF_BIT(comp_ref_p);
        // Decode forward references.
        if (!bit) {
          const int bit1 = READ_REF_BIT(comp_ref_p1);
          ref_frame[!idx] = cm->comp_fwd_ref[bit1 ? 1 : 0];
        } else {
          const int bit2 = READ_REF_BIT(comp_ref_p2);
          ref_frame[!idx] = cm->comp_fwd_ref[bit2 ? 3 : 2];
        }
  
        // Decode backward references.
        const int bit_bwd = READ_REF_BIT(comp_bwdref_p);
        if (!bit_bwd) {
          const int bit1_bwd = READ_REF_BIT(comp_bwdref_p1);
          ref_frame[idx] = cm->comp_bwd_ref[bit1_bwd];
        } else {
          ref_frame[idx] = cm->comp_bwd_ref[2];
        }
      } else if (mode == SINGLE_REFERENCE) {
        const int bit0 = READ_REF_BIT(single_ref_p1);
        if (bit0) {
          const int bit1 = READ_REF_BIT(single_ref_p2);
          if (!bit1) {
            const int bit5 = READ_REF_BIT(single_ref_p6);
            ref_frame[0] = bit5 ? ALTREF2_FRAME : BWDREF_FRAME;
          } else {
            ref_frame[0] = ALTREF_FRAME;
          }
        } else {
          const int bit2 = READ_REF_BIT(single_ref_p3);
          if (bit2) {
            const int bit4 = READ_REF_BIT(single_ref_p5);
            ref_frame[0] = bit4 ? GOLDEN_FRAME : LAST3_FRAME;
          } else {
            const int bit3 = READ_REF_BIT(single_ref_p4);
            ref_frame[0] = bit3 ? LAST2_FRAME : LAST_FRAME;
          }
        }
  
        ref_frame[1] = NONE_FRAME;
      } else {
        assert(0 && "Invalid prediction mode.");
      }
    }
  }
  
  static INLINE void read_mb_interp_filter(AV1_COMMON *const cm,
                                           MACROBLOCKD *const xd,
                                           MB_MODE_INFO *const mbmi,
                                           aom_reader *r) {
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  
    if (!av1_is_interp_needed(xd)) {
      set_default_interp_filters(mbmi, cm->interp_filter);
      return;
    }
  
    if (cm->interp_filter != SWITCHABLE) {
      mbmi->interp_filters = av1_broadcast_interp_filter(cm->interp_filter);
    } else {
      InterpFilter ref0_filter[2] = { EIGHTTAP_REGULAR, EIGHTTAP_REGULAR };
      for (int dir = 0; dir < 2; ++dir) {
        const int ctx = av1_get_pred_context_switchable_interp(xd, dir);
        ref0_filter[dir] = (InterpFilter)aom_read_symbol(
            r, ec_ctx->switchable_interp_cdf[ctx], SWITCHABLE_FILTERS, ACCT_STR);
        if (cm->seq_params.enable_dual_filter == 0) {
          ref0_filter[1] = ref0_filter[0];
          break;
        }
      }
      // The index system works as: (0, 1) -> (vertical, horizontal) filter types
      mbmi->interp_filters =
          av1_make_interp_filters(ref0_filter[0], ref0_filter[1]);
    }
  }
  
  static void read_intra_block_mode_info(AV1_COMMON *const cm, const int mi_row,
                                         const int mi_col, MACROBLOCKD *const xd,
                                         MB_MODE_INFO *const mbmi,
                                         aom_reader *r) {
    const BLOCK_SIZE bsize = mbmi->sb_type;
    const int use_angle_delta = av1_use_angle_delta(bsize);
  
    mbmi->ref_frame[0] = INTRA_FRAME;
    mbmi->ref_frame[1] = NONE_FRAME;
  
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  
    mbmi->mode = read_intra_mode(r, ec_ctx->y_mode_cdf[size_group_lookup[bsize]]);
  
    mbmi->angle_delta[PLANE_TYPE_Y] =
        use_angle_delta && av1_is_directional_mode(mbmi->mode)
            ? read_angle_delta(r, ec_ctx->angle_delta_cdf[mbmi->mode - V_PRED])
            : 0;
    const int has_chroma =
        is_chroma_reference(mi_row, mi_col, bsize, xd->plane[1].subsampling_x,
                            xd->plane[1].subsampling_y);
    xd->cfl.is_chroma_reference = has_chroma;
    if (!cm->seq_params.monochrome && has_chroma) {
      mbmi->uv_mode =
          read_intra_mode_uv(ec_ctx, r, is_cfl_allowed(xd), mbmi->mode);
      if (mbmi->uv_mode == UV_CFL_PRED) {
        mbmi->cfl_alpha_idx =
            read_cfl_alphas(xd->tile_ctx, r, &mbmi->cfl_alpha_signs);
      }
      mbmi->angle_delta[PLANE_TYPE_UV] =
          use_angle_delta && av1_is_directional_mode(get_uv_mode(mbmi->uv_mode))
              ? read_angle_delta(r,
                                 ec_ctx->angle_delta_cdf[mbmi->uv_mode - V_PRED])
              : 0;
    } else {
      // Avoid decoding angle_info if there is is no chroma prediction
      mbmi->uv_mode = UV_DC_PRED;
    }
    xd->cfl.store_y = store_cfl_required(cm, xd);
  
    mbmi->palette_mode_info.palette_size[0] = 0;
    mbmi->palette_mode_info.palette_size[1] = 0;
    if (av1_allow_palette(cm->allow_screen_content_tools, bsize))
      read_palette_mode_info(cm, xd, mi_row, mi_col, r);
  
    read_filter_intra_mode_info(cm, xd, r);
  }
  
  static INLINE int is_mv_valid(const MV *mv) {
    return mv->row > MV_LOW && mv->row < MV_UPP && mv->col > MV_LOW &&
           mv->col < MV_UPP;
  }
  
  static INLINE int assign_mv(AV1_COMMON *cm, MACROBLOCKD *xd,
                              PREDICTION_MODE mode,
                              MV_REFERENCE_FRAME ref_frame[2], int_mv mv[2],
                              int_mv ref_mv[2], int_mv nearest_mv[2],
                              int_mv near_mv[2], int mi_row, int mi_col,
                              int is_compound, int allow_hp, aom_reader *r) {
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
    MB_MODE_INFO *mbmi = xd->mi[0];
    BLOCK_SIZE bsize = mbmi->sb_type;
    if (cm->cur_frame_force_integer_mv) {
      allow_hp = MV_SUBPEL_NONE;
    }
    switch (mode) {
      case NEWMV: {
        nmv_context *const nmvc = &ec_ctx->nmvc;
        read_mv(r, &mv[0].as_mv, &ref_mv[0].as_mv, nmvc, allow_hp);
        break;
      }
      case NEARESTMV: {
        mv[0].as_int = nearest_mv[0].as_int;
        break;
      }
      case NEARMV: {
        mv[0].as_int = near_mv[0].as_int;
        break;
      }
      case GLOBALMV: {
        mv[0].as_int =
            gm_get_motion_vector(&cm->global_motion[ref_frame[0]],
                                 cm->allow_high_precision_mv, bsize, mi_col,
                                 mi_row, cm->cur_frame_force_integer_mv)
                .as_int;
        break;
      }
      case NEW_NEWMV: {
        assert(is_compound);
        for (int i = 0; i < 2; ++i) {
          nmv_context *const nmvc = &ec_ctx->nmvc;
          read_mv(r, &mv[i].as_mv, &ref_mv[i].as_mv, nmvc, allow_hp);
        }
        break;
      }
      case NEAREST_NEARESTMV: {
        assert(is_compound);
        mv[0].as_int = nearest_mv[0].as_int;
        mv[1].as_int = nearest_mv[1].as_int;
        break;
      }
      case NEAR_NEARMV: {
        assert(is_compound);
        mv[0].as_int = near_mv[0].as_int;
        mv[1].as_int = near_mv[1].as_int;
        break;
      }
      case NEW_NEARESTMV: {
        nmv_context *const nmvc = &ec_ctx->nmvc;
        read_mv(r, &mv[0].as_mv, &ref_mv[0].as_mv, nmvc, allow_hp);
        assert(is_compound);
        mv[1].as_int = nearest_mv[1].as_int;
        break;
      }
      case NEAREST_NEWMV: {
        nmv_context *const nmvc = &ec_ctx->nmvc;
        mv[0].as_int = nearest_mv[0].as_int;
        read_mv(r, &mv[1].as_mv, &ref_mv[1].as_mv, nmvc, allow_hp);
        assert(is_compound);
        break;
      }
      case NEAR_NEWMV: {
        nmv_context *const nmvc = &ec_ctx->nmvc;
        mv[0].as_int = near_mv[0].as_int;
        read_mv(r, &mv[1].as_mv, &ref_mv[1].as_mv, nmvc, allow_hp);
        assert(is_compound);
        break;
      }
      case NEW_NEARMV: {
        nmv_context *const nmvc = &ec_ctx->nmvc;
        read_mv(r, &mv[0].as_mv, &ref_mv[0].as_mv, nmvc, allow_hp);
        assert(is_compound);
        mv[1].as_int = near_mv[1].as_int;
        break;
      }
      case GLOBAL_GLOBALMV: {
        assert(is_compound);
        mv[0].as_int =
            gm_get_motion_vector(&cm->global_motion[ref_frame[0]],
                                 cm->allow_high_precision_mv, bsize, mi_col,
                                 mi_row, cm->cur_frame_force_integer_mv)
                .as_int;
        mv[1].as_int =
            gm_get_motion_vector(&cm->global_motion[ref_frame[1]],
                                 cm->allow_high_precision_mv, bsize, mi_col,
                                 mi_row, cm->cur_frame_force_integer_mv)
                .as_int;
        break;
      }
      default: { return 0; }
    }
  
    int ret = is_mv_valid(&mv[0].as_mv);
    if (is_compound) {
      ret = ret && is_mv_valid(&mv[1].as_mv);
    }
    return ret;
  }
  
  static int read_is_inter_block(AV1_COMMON *const cm, MACROBLOCKD *const xd,
                                 int segment_id, aom_reader *r) {
    if (segfeature_active(&cm->seg, segment_id, SEG_LVL_REF_FRAME)) {
      const int frame = get_segdata(&cm->seg, segment_id, SEG_LVL_REF_FRAME);
      if (frame < LAST_FRAME) return 0;
      return frame != INTRA_FRAME;
    }
    if (segfeature_active(&cm->seg, segment_id, SEG_LVL_GLOBALMV)) {
      return 1;
    }
    const int ctx = av1_get_intra_inter_context(xd);
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
    const int is_inter =
        aom_read_symbol(r, ec_ctx->intra_inter_cdf[ctx], 2, ACCT_STR);
    return is_inter;
  }
  
  #if DEC_MISMATCH_DEBUG
  static void dec_dump_logs(AV1_COMMON *cm, MB_MODE_INFO *const mbmi, int mi_row,
                            int mi_col, int16_t mode_ctx) {
    int_mv mv[2] = { { 0 } };
    for (int ref = 0; ref < 1 + has_second_ref(mbmi); ++ref)
      mv[ref].as_mv = mbmi->mv[ref].as_mv;
  
    const int16_t newmv_ctx = mode_ctx & NEWMV_CTX_MASK;
    int16_t zeromv_ctx = -1;
    int16_t refmv_ctx = -1;
    if (mbmi->mode != NEWMV) {
      zeromv_ctx = (mode_ctx >> GLOBALMV_OFFSET) & GLOBALMV_CTX_MASK;
      if (mbmi->mode != GLOBALMV)
        refmv_ctx = (mode_ctx >> REFMV_OFFSET) & REFMV_CTX_MASK;
    }
  
  #define FRAME_TO_CHECK 11
    if (cm->current_video_frame == FRAME_TO_CHECK && cm->show_frame == 1) {
      printf(
          "=== DECODER ===: "
          "Frame=%d, (mi_row,mi_col)=(%d,%d), skip_mode=%d, mode=%d, bsize=%d, "
          "show_frame=%d, mv[0]=(%d,%d), mv[1]=(%d,%d), ref[0]=%d, "
          "ref[1]=%d, motion_mode=%d, mode_ctx=%d, "
          "newmv_ctx=%d, zeromv_ctx=%d, refmv_ctx=%d, tx_size=%d\n",
          cm->current_video_frame, mi_row, mi_col, mbmi->skip_mode, mbmi->mode,
          mbmi->sb_type, cm->show_frame, mv[0].as_mv.row, mv[0].as_mv.col,
          mv[1].as_mv.row, mv[1].as_mv.col, mbmi->ref_frame[0],
          mbmi->ref_frame[1], mbmi->motion_mode, mode_ctx, newmv_ctx, zeromv_ctx,
          refmv_ctx, mbmi->tx_size);
    }
  }
  #endif  // DEC_MISMATCH_DEBUG
  
  static void read_inter_block_mode_info(AV1Decoder *const pbi,
                                         MACROBLOCKD *const xd,
                                         MB_MODE_INFO *const mbmi, int mi_row,
                                         int mi_col, aom_reader *r) {
    AV1_COMMON *const cm = &pbi->common;
    const BLOCK_SIZE bsize = mbmi->sb_type;
    const int allow_hp = cm->allow_high_precision_mv;
    int_mv nearestmv[2], nearmv[2];
    int_mv ref_mvs[MODE_CTX_REF_FRAMES][MAX_MV_REF_CANDIDATES] = { { { 0 } } };
    int16_t inter_mode_ctx[MODE_CTX_REF_FRAMES];
    int pts[SAMPLES_ARRAY_SIZE], pts_inref[SAMPLES_ARRAY_SIZE];
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  
    mbmi->uv_mode = UV_DC_PRED;
    mbmi->palette_mode_info.palette_size[0] = 0;
    mbmi->palette_mode_info.palette_size[1] = 0;
  
    av1_collect_neighbors_ref_counts(xd);
  
    read_ref_frames(cm, xd, r, mbmi->segment_id, mbmi->ref_frame);
    const int is_compound = has_second_ref(mbmi);
  
    MV_REFERENCE_FRAME ref_frame = av1_ref_frame_type(mbmi->ref_frame);
    int_mv global_mvs[REF_FRAMES];
    av1_find_mv_refs(cm, xd, mbmi, ref_frame, xd->ref_mv_count, xd->ref_mv_stack,
                     ref_mvs, global_mvs, mi_row, mi_col, inter_mode_ctx);
  
    int mode_ctx = av1_mode_context_analyzer(inter_mode_ctx, mbmi->ref_frame);
    mbmi->ref_mv_idx = 0;
  
    if (mbmi->skip_mode) {
      assert(is_compound);
      mbmi->mode = NEAREST_NEARESTMV;
    } else {
      if (segfeature_active(&cm->seg, mbmi->segment_id, SEG_LVL_SKIP) ||
          segfeature_active(&cm->seg, mbmi->segment_id, SEG_LVL_GLOBALMV)) {
        mbmi->mode = GLOBALMV;
      } else {
        if (is_compound)
          mbmi->mode = read_inter_compound_mode(xd, r, mode_ctx);
        else
          mbmi->mode = read_inter_mode(ec_ctx, r, mode_ctx);
        if (mbmi->mode == NEWMV || mbmi->mode == NEW_NEWMV ||
            have_nearmv_in_inter_mode(mbmi->mode))
          read_drl_idx(ec_ctx, xd, mbmi, r);
      }
    }
  
    if (is_compound != is_inter_compound_mode(mbmi->mode)) {
      aom_internal_error(xd->error_info, AOM_CODEC_CORRUPT_FRAME,
                         "Prediction mode %d invalid with ref frame %d %d",
                         mbmi->mode, mbmi->ref_frame[0], mbmi->ref_frame[1]);
    }
  
    if (!is_compound && mbmi->mode != GLOBALMV) {
      av1_find_best_ref_mvs(allow_hp, ref_mvs[mbmi->ref_frame[0]], &nearestmv[0],
                            &nearmv[0], cm->cur_frame_force_integer_mv);
    }
  
    if (is_compound && mbmi->mode != GLOBAL_GLOBALMV) {
      int ref_mv_idx = mbmi->ref_mv_idx + 1;
      nearestmv[0] = xd->ref_mv_stack[ref_frame][0].this_mv;
      nearestmv[1] = xd->ref_mv_stack[ref_frame][0].comp_mv;
      nearmv[0] = xd->ref_mv_stack[ref_frame][ref_mv_idx].this_mv;
      nearmv[1] = xd->ref_mv_stack[ref_frame][ref_mv_idx].comp_mv;
      lower_mv_precision(&nearestmv[0].as_mv, allow_hp,
                         cm->cur_frame_force_integer_mv);
      lower_mv_precision(&nearestmv[1].as_mv, allow_hp,
                         cm->cur_frame_force_integer_mv);
      lower_mv_precision(&nearmv[0].as_mv, allow_hp,
                         cm->cur_frame_force_integer_mv);
      lower_mv_precision(&nearmv[1].as_mv, allow_hp,
                         cm->cur_frame_force_integer_mv);
    } else if (mbmi->ref_mv_idx > 0 && mbmi->mode == NEARMV) {
      int_mv cur_mv =
          xd->ref_mv_stack[mbmi->ref_frame[0]][1 + mbmi->ref_mv_idx].this_mv;
      nearmv[0] = cur_mv;
    }
  
    int_mv ref_mv[2];
    ref_mv[0] = nearestmv[0];
    ref_mv[1] = nearestmv[1];
  
    if (is_compound) {
      int ref_mv_idx = mbmi->ref_mv_idx;
      // Special case: NEAR_NEWMV and NEW_NEARMV modes use
      // 1 + mbmi->ref_mv_idx (like NEARMV) instead of
      // mbmi->ref_mv_idx (like NEWMV)
      if (mbmi->mode == NEAR_NEWMV || mbmi->mode == NEW_NEARMV)
        ref_mv_idx = 1 + mbmi->ref_mv_idx;
  
      // TODO(jingning, yunqing): Do we need a lower_mv_precision() call here?
      if (compound_ref0_mode(mbmi->mode) == NEWMV)
        ref_mv[0] = xd->ref_mv_stack[ref_frame][ref_mv_idx].this_mv;
  
      if (compound_ref1_mode(mbmi->mode) == NEWMV)
        ref_mv[1] = xd->ref_mv_stack[ref_frame][ref_mv_idx].comp_mv;
    } else {
      if (mbmi->mode == NEWMV) {
        if (xd->ref_mv_count[ref_frame] > 1)
          ref_mv[0] = xd->ref_mv_stack[ref_frame][mbmi->ref_mv_idx].this_mv;
      }
    }
  
    if (mbmi->skip_mode) {
      assert(mbmi->mode == NEAREST_NEARESTMV);
      mbmi->mv[0].as_int = nearestmv[0].as_int;
      mbmi->mv[1].as_int = nearestmv[1].as_int;
    } else {
      int mv_corrupted_flag =
          !assign_mv(cm, xd, mbmi->mode, mbmi->ref_frame, mbmi->mv, ref_mv,
                     nearestmv, nearmv, mi_row, mi_col, is_compound, allow_hp, r);
      aom_merge_corrupted_flag(&xd->corrupted, mv_corrupted_flag);
    }
  
    mbmi->use_wedge_interintra = 0;
    if (cm->seq_params.enable_interintra_compound && !mbmi->skip_mode &&
        is_interintra_allowed(mbmi)) {
      const int bsize_group = size_group_lookup[bsize];
      const int interintra =
          aom_read_symbol(r, ec_ctx->interintra_cdf[bsize_group], 2, ACCT_STR);
      assert(mbmi->ref_frame[1] == NONE_FRAME);
      if (interintra) {
        const INTERINTRA_MODE interintra_mode =
            read_interintra_mode(xd, r, bsize_group);
        mbmi->ref_frame[1] = INTRA_FRAME;
        mbmi->interintra_mode = interintra_mode;
        mbmi->angle_delta[PLANE_TYPE_Y] = 0;
        mbmi->angle_delta[PLANE_TYPE_UV] = 0;
        mbmi->filter_intra_mode_info.use_filter_intra = 0;
        if (is_interintra_wedge_used(bsize)) {
          mbmi->use_wedge_interintra = aom_read_symbol(
              r, ec_ctx->wedge_interintra_cdf[bsize], 2, ACCT_STR);
          if (mbmi->use_wedge_interintra) {
            mbmi->interintra_wedge_index =
                aom_read_symbol(r, ec_ctx->wedge_idx_cdf[bsize], 16, ACCT_STR);
            mbmi->interintra_wedge_sign = 0;
          }
        }
      }
    }
  
    for (int ref = 0; ref < 1 + has_second_ref(mbmi); ++ref) {
      const MV_REFERENCE_FRAME frame = mbmi->ref_frame[ref];
      RefBuffer *ref_buf = &cm->frame_refs[frame - LAST_FRAME];
  
      xd->block_refs[ref] = ref_buf;
    }
  
    mbmi->motion_mode = SIMPLE_TRANSLATION;
    if (is_motion_variation_allowed_bsize(mbmi->sb_type) && !mbmi->skip_mode &&
        !has_second_ref(mbmi))
      mbmi->num_proj_ref[0] = findSamples(cm, xd, mi_row, mi_col, pts, pts_inref);
    av1_count_overlappable_neighbors(cm, xd, mi_row, mi_col);
  
    if (mbmi->ref_frame[1] != INTRA_FRAME)
      mbmi->motion_mode = read_motion_mode(cm, xd, mbmi, r);
  
    // init
    mbmi->comp_group_idx = 0;
    mbmi->compound_idx = 1;
    mbmi->interinter_comp.type = COMPOUND_AVERAGE;
  
    if (has_second_ref(mbmi) && !mbmi->skip_mode) {
      // Read idx to indicate current compound inter prediction mode group
      const int masked_compound_used = is_any_masked_compound_used(bsize) &&
                                       cm->seq_params.enable_masked_compound;
  
      if (masked_compound_used) {
        const int ctx_comp_group_idx = get_comp_group_idx_context(xd);
        mbmi->comp_group_idx = aom_read_symbol(
            r, ec_ctx->comp_group_idx_cdf[ctx_comp_group_idx], 2, ACCT_STR);
      }
  
      if (mbmi->comp_group_idx == 0) {
        if (cm->seq_params.enable_jnt_comp) {
          const int comp_index_ctx = get_comp_index_context(cm, xd);
          mbmi->compound_idx = aom_read_symbol(
              r, ec_ctx->compound_index_cdf[comp_index_ctx], 2, ACCT_STR);
        } else {
          // Distance-weighted compound is disabled, so always use average
          mbmi->compound_idx = 1;
        }
      } else {
        assert(cm->reference_mode != SINGLE_REFERENCE &&
               is_inter_compound_mode(mbmi->mode) &&
               mbmi->motion_mode == SIMPLE_TRANSLATION);
        assert(masked_compound_used);
  
        // compound_diffwtd, wedge
        if (is_interinter_compound_used(COMPOUND_WEDGE, bsize))
          mbmi->interinter_comp.type =
              1 + aom_read_symbol(r, ec_ctx->compound_type_cdf[bsize],
                                  COMPOUND_TYPES - 1, ACCT_STR);
        else
          mbmi->interinter_comp.type = COMPOUND_DIFFWTD;
  
        if (mbmi->interinter_comp.type == COMPOUND_WEDGE) {
          assert(is_interinter_compound_used(COMPOUND_WEDGE, bsize));
          mbmi->interinter_comp.wedge_index =
              aom_read_symbol(r, ec_ctx->wedge_idx_cdf[bsize], 16, ACCT_STR);
          mbmi->interinter_comp.wedge_sign = aom_read_bit(r, ACCT_STR);
        } else {
          assert(mbmi->interinter_comp.type == COMPOUND_DIFFWTD);
          mbmi->interinter_comp.mask_type =
              aom_read_literal(r, MAX_DIFFWTD_MASK_BITS, ACCT_STR);
        }
      }
    }
  
    read_mb_interp_filter(cm, xd, mbmi, r);
  
    if (mbmi->motion_mode == WARPED_CAUSAL) {
      mbmi->wm_params[0].wmtype = DEFAULT_WMTYPE;
      mbmi->wm_params[0].invalid = 0;
  
      if (mbmi->num_proj_ref[0] > 1)
        mbmi->num_proj_ref[0] = selectSamples(&mbmi->mv[0].as_mv, pts, pts_inref,
                                              mbmi->num_proj_ref[0], bsize);
  
      if (find_projection(mbmi->num_proj_ref[0], pts, pts_inref, bsize,
                          mbmi->mv[0].as_mv.row, mbmi->mv[0].as_mv.col,
                          &mbmi->wm_params[0], mi_row, mi_col)) {
  #if WARPED_MOTION_DEBUG
        printf("Warning: unexpected warped model from aomenc\n");
  #endif
        mbmi->wm_params[0].invalid = 1;
      }
    }
  
    xd->cfl.is_chroma_reference = is_chroma_reference(
        mi_row, mi_col, bsize, cm->subsampling_x, cm->subsampling_y);
    xd->cfl.store_y = store_cfl_required(cm, xd);
  
  #if DEC_MISMATCH_DEBUG
    dec_dump_logs(cm, mi, mi_row, mi_col, mode_ctx);
  #endif  // DEC_MISMATCH_DEBUG
  }
  
  static void read_inter_frame_mode_info(AV1Decoder *const pbi,
                                         MACROBLOCKD *const xd, int mi_row,
                                         int mi_col, aom_reader *r) {
    AV1_COMMON *const cm = &pbi->common;
    MB_MODE_INFO *const mbmi = xd->mi[0];
    int inter_block = 1;
  
    mbmi->mv[0].as_int = 0;
    mbmi->mv[1].as_int = 0;
    mbmi->segment_id = read_inter_segment_id(cm, xd, mi_row, mi_col, 1, r);
  
    mbmi->skip_mode = read_skip_mode(cm, xd, mbmi->segment_id, r);
  
    if (mbmi->skip_mode)
      mbmi->skip = 1;
    else
      mbmi->skip = read_skip(cm, xd, mbmi->segment_id, r);
  
    mbmi->segment_id = read_inter_segment_id(cm, xd, mi_row, mi_col, 0, r);
  
    read_cdef(cm, r, xd, mi_col, mi_row);
  
    if (cm->delta_q_present_flag) {
      xd->current_qindex +=
          read_delta_qindex(cm, xd, r, mbmi, mi_col, mi_row) * cm->delta_q_res;
      /* Normative: Clamp to [1,MAXQ] to not interfere with lossless mode */
      xd->current_qindex = clamp(xd->current_qindex, 1, MAXQ);
      if (cm->delta_lf_present_flag) {
        if (cm->delta_lf_multi) {
          const int frame_lf_count =
              av1_num_planes(cm) > 1 ? FRAME_LF_COUNT : FRAME_LF_COUNT - 2;
          for (int lf_id = 0; lf_id < frame_lf_count; ++lf_id) {
            const int tmp_lvl =
                xd->delta_lf[lf_id] +
                read_delta_lflevel(cm, xd, r, lf_id, mbmi, mi_col, mi_row) *
                    cm->delta_lf_res;
            mbmi->delta_lf[lf_id] = xd->delta_lf[lf_id] =
                clamp(tmp_lvl, -MAX_LOOP_FILTER, MAX_LOOP_FILTER);
          }
        } else {
          const int tmp_lvl =
              xd->delta_lf_from_base +
              read_delta_lflevel(cm, xd, r, -1, mbmi, mi_col, mi_row) *
                  cm->delta_lf_res;
          mbmi->delta_lf_from_base = xd->delta_lf_from_base =
              clamp(tmp_lvl, -MAX_LOOP_FILTER, MAX_LOOP_FILTER);
        }
      }
    }
  
    if (!mbmi->skip_mode)
      inter_block = read_is_inter_block(cm, xd, mbmi->segment_id, r);
  
    mbmi->current_qindex = xd->current_qindex;
  
    xd->above_txfm_context = cm->above_txfm_context[xd->tile.tile_row] + mi_col;
    xd->left_txfm_context =
        xd->left_txfm_context_buffer + (mi_row & MAX_MIB_MASK);
  
    if (inter_block)
      read_inter_block_mode_info(pbi, xd, mbmi, mi_row, mi_col, r);
    else
      read_intra_block_mode_info(cm, mi_row, mi_col, xd, mbmi, r);
  }
  
  static void intra_copy_frame_mvs(AV1_COMMON *const cm, int mi_row, int mi_col,
                                   int x_mis, int y_mis) {
    const int frame_mvs_stride = ROUND_POWER_OF_TWO(cm->mi_cols, 1);
    MV_REF *frame_mvs =
        cm->cur_frame->mvs + (mi_row >> 1) * frame_mvs_stride + (mi_col >> 1);
    x_mis = ROUND_POWER_OF_TWO(x_mis, 1);
    y_mis = ROUND_POWER_OF_TWO(y_mis, 1);
  
    for (int h = 0; h < y_mis; h++) {
      MV_REF *mv = frame_mvs;
      for (int w = 0; w < x_mis; w++) {
        mv->ref_frame = NONE_FRAME;
        mv++;
      }
      frame_mvs += frame_mvs_stride;
    }
  }
  
  void av1_read_mode_info(AV1Decoder *const pbi, MACROBLOCKD *xd, int mi_row,
                          int mi_col, aom_reader *r, int x_mis, int y_mis) {
    AV1_COMMON *const cm = &pbi->common;
    MB_MODE_INFO *const mi = xd->mi[0];
    mi->use_intrabc = 0;
  
    if (frame_is_intra_only(cm)) {
      read_intra_frame_mode_info(cm, xd, mi_row, mi_col, r);
      intra_copy_frame_mvs(cm, mi_row, mi_col, x_mis, y_mis);
    } else {
      read_inter_frame_mode_info(pbi, xd, mi_row, mi_col, r);
      av1_copy_frame_mvs(cm, mi, mi_row, mi_col, x_mis, y_mis);
    }
  }
  