bitstream.c

/*
 * 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 <limits.h>
#include <stdio.h>

#include "aom/aom_encoder.h"
#include "aom_dsp/bitwriter_buffer.h"
#include "aom_dsp/aom_dsp_common.h"
#include "aom_dsp/binary_codes_writer.h"
#include "aom_mem/aom_mem.h"
#include "aom_ports/mem_ops.h"
#include "aom_ports/system_state.h"
#if CONFIG_BITSTREAM_DEBUG
#include "aom_util/debug_util.h"
#endif  // CONFIG_BITSTREAM_DEBUG

#if CONFIG_CDEF
#include "av1/common/cdef.h"
#endif  // CONFIG_CDEF
#include "av1/common/entropy.h"
#include "av1/common/entropymode.h"
#include "av1/common/entropymv.h"
#include "av1/common/mvref_common.h"
#include "av1/common/odintrin.h"
#include "av1/common/pred_common.h"
#include "av1/common/reconinter.h"
#if CONFIG_EXT_INTRA
#include "av1/common/reconintra.h"
#endif  // CONFIG_EXT_INTRA
#include "av1/common/seg_common.h"
#include "av1/common/tile_common.h"

#if CONFIG_ANS
#include "aom_dsp/buf_ans.h"
#endif  // CONFIG_ANS
#if CONFIG_LV_MAP
#include "av1/encoder/encodetxb.h"
#endif  // CONFIG_LV_MAP
#include "av1/encoder/bitstream.h"
#include "av1/encoder/cost.h"
#include "av1/encoder/encodemv.h"
#include "av1/encoder/mcomp.h"
#if CONFIG_PALETTE && CONFIG_PALETTE_DELTA_ENCODING
#include "av1/encoder/palette.h"
#endif  // CONFIG_PALETTE && CONFIG_PALETTE_DELTA_ENCODING
#include "av1/encoder/segmentation.h"
#include "av1/encoder/subexp.h"
#include "av1/encoder/tokenize.h"
#if CONFIG_PVQ
#include "av1/encoder/pvq_encoder.h"
#endif

#define ENC_MISMATCH_DEBUG 0

#if CONFIG_EXT_INTER && CONFIG_COMPOUND_SINGLEREF
static struct av1_token
    inter_singleref_comp_mode_encodings[INTER_SINGLEREF_COMP_MODES];
#endif  // CONFIG_EXT_INTER && CONFIG_COMPOUND_SINGLEREF

#if CONFIG_EXT_INTRA || CONFIG_FILTER_INTRA || CONFIG_PALETTE
static INLINE void write_uniform(aom_writer *w, int n, int v) {
  const int l = get_unsigned_bits(n);
  const int m = (1 << l) - n;
  if (l == 0) return;
  if (v < m) {
    aom_write_literal(w, v, l - 1);
  } else {
    aom_write_literal(w, m + ((v - m) >> 1), l - 1);
    aom_write_literal(w, (v - m) & 1, 1);
  }
}
#endif  // CONFIG_EXT_INTRA || CONFIG_FILTER_INTRA || CONFIG_PALETTE

#if CONFIG_EXT_TX
static struct av1_token ext_tx_inter_encodings[EXT_TX_SETS_INTER][TX_TYPES];
static struct av1_token ext_tx_intra_encodings[EXT_TX_SETS_INTRA][TX_TYPES];
#else
static struct av1_token ext_tx_encodings[TX_TYPES];
#endif  // CONFIG_EXT_TX
#if CONFIG_EXT_INTRA
#if CONFIG_INTRA_INTERP
static struct av1_token intra_filter_encodings[INTRA_FILTERS];
#endif  // CONFIG_INTRA_INTERP
#endif  // CONFIG_EXT_INTRA
#if CONFIG_EXT_INTER
#if CONFIG_INTERINTRA
static struct av1_token interintra_mode_encodings[INTERINTRA_MODES];
#endif
#if CONFIG_COMPOUND_SEGMENT || CONFIG_WEDGE
static struct av1_token compound_type_encodings[COMPOUND_TYPES];
#endif  // CONFIG_COMPOUND_SEGMENT || CONFIG_WEDGE
#endif  // CONFIG_EXT_INTER
#if CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
#if CONFIG_NCOBMC_ADAPT_WEIGHT
static struct av1_token ncobmc_mode_encodings[MAX_NCOBMC_MODES];
#endif
#endif  // CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
#if CONFIG_LOOP_RESTORATION
static struct av1_token switchable_restore_encodings[RESTORE_SWITCHABLE_TYPES];
#endif  // CONFIG_LOOP_RESTORATION
static void write_uncompressed_header(AV1_COMP *cpi,
                                      struct aom_write_bit_buffer *wb);
static uint32_t write_compressed_header(AV1_COMP *cpi, uint8_t *data);
static int remux_tiles(const AV1_COMMON *const cm, uint8_t *dst,
                       const uint32_t data_size, const uint32_t max_tile_size,
                       const uint32_t max_tile_col_size,
                       int *const tile_size_bytes,
                       int *const tile_col_size_bytes);

void av1_encode_token_init(void) {
#if CONFIG_EXT_TX
  int s;
#endif  // CONFIG_EXT_TX
#if CONFIG_EXT_TX
  for (s = 1; s < EXT_TX_SETS_INTER; ++s) {
    av1_tokens_from_tree(ext_tx_inter_encodings[s], av1_ext_tx_inter_tree[s]);
  }
  for (s = 1; s < EXT_TX_SETS_INTRA; ++s) {
    av1_tokens_from_tree(ext_tx_intra_encodings[s], av1_ext_tx_intra_tree[s]);
  }
#else
  av1_tokens_from_tree(ext_tx_encodings, av1_ext_tx_tree);
#endif  // CONFIG_EXT_TX

#if CONFIG_EXT_INTRA && CONFIG_INTRA_INTERP
  av1_tokens_from_tree(intra_filter_encodings, av1_intra_filter_tree);
#endif  // CONFIG_EXT_INTRA && CONFIG_INTRA_INTERP
#if CONFIG_EXT_INTER
#if CONFIG_INTERINTRA
  av1_tokens_from_tree(interintra_mode_encodings, av1_interintra_mode_tree);
#endif  // CONFIG_INTERINTRA
#if CONFIG_COMPOUND_SINGLEREF
  av1_tokens_from_tree(inter_singleref_comp_mode_encodings,
                       av1_inter_singleref_comp_mode_tree);
#endif  // CONFIG_COMPOUND_SINGLEREF
#if CONFIG_COMPOUND_SEGMENT || CONFIG_WEDGE
  av1_tokens_from_tree(compound_type_encodings, av1_compound_type_tree);
#endif  // CONFIG_COMPOUND_SEGMENT || CONFIG_WEDGE
#endif  // CONFIG_EXT_INTER
#if CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
#if CONFIG_NCOBMC_ADAPT_WEIGHT
  av1_tokens_from_tree(ncobmc_mode_encodings, av1_ncobmc_mode_tree);
#endif
#endif  // CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
#if CONFIG_LOOP_RESTORATION
  av1_tokens_from_tree(switchable_restore_encodings,
                       av1_switchable_restore_tree);
#endif  // CONFIG_LOOP_RESTORATION

  /* This hack is necessary when CONFIG_DUAL_FILTER is enabled because the five
      SWITCHABLE_FILTERS are not consecutive, e.g., 0, 1, 2, 3, 4, when doing
      an in-order traversal of the av1_switchable_interp_tree structure. */
  av1_indices_from_tree(av1_switchable_interp_ind, av1_switchable_interp_inv,
                        av1_switchable_interp_tree);
/* This hack is necessary because the four TX_TYPES are not consecutive,
    e.g., 0, 1, 2, 3, when doing an in-order traversal of the av1_ext_tx_tree
    structure. */
#if CONFIG_EXT_TX
  for (s = 1; s < EXT_TX_SETS_INTRA; ++s)
    av1_indices_from_tree(av1_ext_tx_intra_ind[s], av1_ext_tx_intra_inv[s],
                          av1_ext_tx_intra_tree[s]);
  for (s = 1; s < EXT_TX_SETS_INTER; ++s)
    av1_indices_from_tree(av1_ext_tx_inter_ind[s], av1_ext_tx_inter_inv[s],
                          av1_ext_tx_inter_tree[s]);
#else
  av1_indices_from_tree(av1_ext_tx_ind, av1_ext_tx_inv, av1_ext_tx_tree);
#endif
}

static void write_intra_mode_kf(const AV1_COMMON *cm, FRAME_CONTEXT *frame_ctx,
                                const MODE_INFO *mi, const MODE_INFO *above_mi,
                                const MODE_INFO *left_mi, int block,
                                PREDICTION_MODE mode, aom_writer *w) {
#if CONFIG_INTRABC
  assert(!is_intrabc_block(&mi->mbmi));
#endif  // CONFIG_INTRABC
  aom_write_symbol(w, av1_intra_mode_ind[mode],
                   get_y_mode_cdf(frame_ctx, mi, above_mi, left_mi, block),
                   INTRA_MODES);
  (void)cm;
}

static void write_inter_mode(aom_writer *w, PREDICTION_MODE mode,
                             FRAME_CONTEXT *ec_ctx, const int16_t mode_ctx) {
  const int16_t newmv_ctx = mode_ctx & NEWMV_CTX_MASK;

#if CONFIG_NEW_MULTISYMBOL
  aom_write_symbol(w, mode != NEWMV, ec_ctx->newmv_cdf[newmv_ctx], 2);
#else
  aom_write(w, mode != NEWMV, ec_ctx->newmv_prob[newmv_ctx]);
#endif

  if (mode != NEWMV) {
    if (mode_ctx & (1 << ALL_ZERO_FLAG_OFFSET)) {
      assert(mode == ZEROMV);
      return;
    }

    const int16_t zeromv_ctx = (mode_ctx >> ZEROMV_OFFSET) & ZEROMV_CTX_MASK;
#if CONFIG_NEW_MULTISYMBOL
    aom_write_symbol(w, mode != ZEROMV, ec_ctx->zeromv_cdf[zeromv_ctx], 2);
#else
    aom_write(w, mode != ZEROMV, ec_ctx->zeromv_prob[zeromv_ctx]);
#endif

    if (mode != ZEROMV) {
      int16_t refmv_ctx = (mode_ctx >> REFMV_OFFSET) & REFMV_CTX_MASK;

      if (mode_ctx & (1 << SKIP_NEARESTMV_OFFSET)) refmv_ctx = 6;
      if (mode_ctx & (1 << SKIP_NEARMV_OFFSET)) refmv_ctx = 7;
      if (mode_ctx & (1 << SKIP_NEARESTMV_SUB8X8_OFFSET)) refmv_ctx = 8;
#if CONFIG_NEW_MULTISYMBOL
      aom_write_symbol(w, mode != NEARESTMV, ec_ctx->refmv_cdf[refmv_ctx], 2);
#else
      aom_write(w, mode != NEARESTMV, ec_ctx->refmv_prob[refmv_ctx]);
#endif
    }
  }
}

static void write_drl_idx(FRAME_CONTEXT *ec_ctx, const MB_MODE_INFO *mbmi,
                          const MB_MODE_INFO_EXT *mbmi_ext, aom_writer *w) {
  uint8_t ref_frame_type = av1_ref_frame_type(mbmi->ref_frame);

  assert(mbmi->ref_mv_idx < 3);

#if CONFIG_EXT_INTER
#if CONFIG_COMPOUND_SINGLEREF
  if (mbmi->mode == NEWMV || mbmi->mode == NEW_NEWMV ||
      mbmi->mode == SR_NEW_NEWMV) {
#else   // !CONFIG_COMPOUND_SINGLEREF
  if (mbmi->mode == NEWMV || mbmi->mode == NEW_NEWMV) {
#endif  // CONFIG_COMPOUND_SINGLEREF
#else   // !CONFIG_EXT_INTER
  if (mbmi->mode == NEWMV) {
#endif  // CONFIG_EXT_INTER
    int idx;
    for (idx = 0; idx < 2; ++idx) {
      if (mbmi_ext->ref_mv_count[ref_frame_type] > idx + 1) {
        uint8_t drl_ctx =
            av1_drl_ctx(mbmi_ext->ref_mv_stack[ref_frame_type], idx);

#if CONFIG_NEW_MULTISYMBOL
        aom_write_symbol(w, mbmi->ref_mv_idx != idx, ec_ctx->drl_cdf[drl_ctx],
                         2);
#else
        aom_write(w, mbmi->ref_mv_idx != idx, ec_ctx->drl_prob[drl_ctx]);
#endif
        if (mbmi->ref_mv_idx == idx) return;
      }
    }
    return;
  }

  if (have_nearmv_in_inter_mode(mbmi->mode)) {
    int idx;
    // TODO(jingning): Temporary solution to compensate the NEARESTMV offset.
    for (idx = 1; idx < 3; ++idx) {
      if (mbmi_ext->ref_mv_count[ref_frame_type] > idx + 1) {
        uint8_t drl_ctx =
            av1_drl_ctx(mbmi_ext->ref_mv_stack[ref_frame_type], idx);
#if CONFIG_NEW_MULTISYMBOL
        aom_write_symbol(w, mbmi->ref_mv_idx != (idx - 1),
                         ec_ctx->drl_cdf[drl_ctx], 2);
#else
        aom_write(w, mbmi->ref_mv_idx != (idx - 1), ec_ctx->drl_prob[drl_ctx]);
#endif
        if (mbmi->ref_mv_idx == (idx - 1)) return;
      }
    }
    return;
  }
}

#if CONFIG_EXT_INTER
static void write_inter_compound_mode(AV1_COMMON *cm, MACROBLOCKD *xd,
                                      aom_writer *w, PREDICTION_MODE mode,
                                      const int16_t mode_ctx) {
  assert(is_inter_compound_mode(mode));
  (void)cm;
  aom_write_symbol(w, INTER_COMPOUND_OFFSET(mode),
                   xd->tile_ctx->inter_compound_mode_cdf[mode_ctx],
                   INTER_COMPOUND_MODES);
}

#if CONFIG_COMPOUND_SINGLEREF
static void write_inter_singleref_comp_mode(MACROBLOCKD *xd, aom_writer *w,
                                            PREDICTION_MODE mode,
                                            const int16_t mode_ctx) {
  assert(is_inter_singleref_comp_mode(mode));
  aom_cdf_prob *const inter_singleref_comp_cdf =
      xd->tile_ctx->inter_singleref_comp_mode_cdf[mode_ctx];

  aom_write_symbol(w, INTER_SINGLEREF_COMP_OFFSET(mode),
                   inter_singleref_comp_cdf, INTER_SINGLEREF_COMP_MODES);
}
#endif  // CONFIG_COMPOUND_SINGLEREF
#endif  // CONFIG_EXT_INTER

static void encode_unsigned_max(struct aom_write_bit_buffer *wb, int data,
                                int max) {
  aom_wb_write_literal(wb, data, get_unsigned_bits(max));
}

#if CONFIG_NCOBMC_ADAPT_WEIGHT
static void prob_diff_update(const aom_tree_index *tree,
                             aom_prob probs[/*n - 1*/],
                             const unsigned int counts[/* n */], int n,
                             int probwt, aom_writer *w) {
  int i;
  unsigned int branch_ct[32][2];

  // Assuming max number of probabilities <= 32
  assert(n <= 32);

  av1_tree_probs_from_distribution(tree, branch_ct, counts);
  for (i = 0; i < n - 1; ++i)
    av1_cond_prob_diff_update(w, &probs[i], branch_ct[i], probwt);
}
#endif

#if CONFIG_VAR_TX
static void write_tx_size_vartx(const AV1_COMMON *cm, MACROBLOCKD *xd,
                                const MB_MODE_INFO *mbmi, TX_SIZE tx_size,
                                int depth, int blk_row, int blk_col,
                                aom_writer *w) {
#if CONFIG_NEW_MULTISYMBOL
  FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  (void)cm;
#endif
  const int tx_row = blk_row >> 1;
  const int tx_col = blk_col >> 1;
  const int max_blocks_high = max_block_high(xd, mbmi->sb_type, 0);
  const int max_blocks_wide = max_block_wide(xd, mbmi->sb_type, 0);

  int ctx = txfm_partition_context(xd->above_txfm_context + blk_col,
                                   xd->left_txfm_context + blk_row,
                                   mbmi->sb_type, tx_size);

  if (blk_row >= max_blocks_high || blk_col >= max_blocks_wide) return;

  if (depth == MAX_VARTX_DEPTH) {
    txfm_partition_update(xd->above_txfm_context + blk_col,
                          xd->left_txfm_context + blk_row, tx_size, tx_size);
    return;
  }

#if CONFIG_RECT_TX_EXT
  if (tx_size == mbmi->inter_tx_size[tx_row][tx_col] ||
      mbmi->tx_size == quarter_txsize_lookup[mbmi->sb_type]) {
#else
  if (tx_size == mbmi->inter_tx_size[tx_row][tx_col]) {
#endif
#if CONFIG_NEW_MULTISYMBOL
    aom_write_symbol(w, 0, ec_ctx->txfm_partition_cdf[ctx], 2);
#else
    aom_write(w, 0, cm->fc->txfm_partition_prob[ctx]);
#endif

    txfm_partition_update(xd->above_txfm_context + blk_col,
                          xd->left_txfm_context + blk_row, tx_size, tx_size);
    // TODO(yuec): set correct txfm partition update for qttx
  } else {
    const TX_SIZE sub_txs = sub_tx_size_map[tx_size];
    const int bsl = tx_size_wide_unit[sub_txs];
    int i;

#if CONFIG_NEW_MULTISYMBOL
    aom_write_symbol(w, 1, ec_ctx->txfm_partition_cdf[ctx], 2);
#else
    aom_write(w, 1, cm->fc->txfm_partition_prob[ctx]);
#endif

    if (tx_size == TX_8X8) {
      txfm_partition_update(xd->above_txfm_context + blk_col,
                            xd->left_txfm_context + blk_row, sub_txs, tx_size);
      return;
    }

    assert(bsl > 0);
    for (i = 0; i < 4; ++i) {
      int offsetr = blk_row + (i >> 1) * bsl;
      int offsetc = blk_col + (i & 0x01) * bsl;
      write_tx_size_vartx(cm, xd, mbmi, sub_txs, depth + 1, offsetr, offsetc,
                          w);
    }
  }
}

#if !CONFIG_NEW_MULTISYMBOL
static void update_txfm_partition_probs(AV1_COMMON *cm, aom_writer *w,
                                        FRAME_COUNTS *counts, int probwt) {
  int k;
  for (k = 0; k < TXFM_PARTITION_CONTEXTS; ++k)
    av1_cond_prob_diff_update(w, &cm->fc->txfm_partition_prob[k],
                              counts->txfm_partition[k], probwt);
}
#endif  // CONFIG_NEW_MULTISYMBOL
#endif

static void write_selected_tx_size(const AV1_COMMON *cm, const MACROBLOCKD *xd,
                                   aom_writer *w) {
  const MB_MODE_INFO *const mbmi = &xd->mi[0]->mbmi;
  const BLOCK_SIZE bsize = mbmi->sb_type;
  FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  (void)cm;
// For sub8x8 blocks the tx_size symbol does not need to be sent
#if CONFIG_CB4X4 && (CONFIG_VAR_TX || CONFIG_EXT_TX) && CONFIG_RECT_TX
  if (bsize > BLOCK_4X4) {
#else
  if (bsize >= BLOCK_8X8) {
#endif
    const TX_SIZE tx_size = mbmi->tx_size;
    const int is_inter = is_inter_block(mbmi);
    const int tx_size_ctx = get_tx_size_context(xd);
    const int tx_size_cat = is_inter ? inter_tx_size_cat_lookup[bsize]
                                     : intra_tx_size_cat_lookup[bsize];
    const TX_SIZE coded_tx_size = txsize_sqr_up_map[tx_size];
    const int depth = tx_size_to_depth(coded_tx_size);
#if CONFIG_EXT_TX && CONFIG_RECT_TX
    assert(IMPLIES(is_rect_tx(tx_size), is_rect_tx_allowed(xd, mbmi)));
#endif  // CONFIG_EXT_TX && CONFIG_RECT_TX

    aom_write_symbol(w, depth, ec_ctx->tx_size_cdf[tx_size_cat][tx_size_ctx],
                     tx_size_cat + 2);
#if CONFIG_RECT_TX_EXT && (CONFIG_EXT_TX || CONFIG_VAR_TX)
    if (is_quarter_tx_allowed(xd, mbmi, is_inter) && tx_size != coded_tx_size)
      aom_write(w, tx_size == quarter_txsize_lookup[bsize],
                cm->fc->quarter_tx_size_prob);
#endif
  }
}

#if !CONFIG_NEW_MULTISYMBOL
static void update_inter_mode_probs(AV1_COMMON *cm, aom_writer *w,
                                    FRAME_COUNTS *counts) {
  int i;
  const int probwt = cm->num_tg;
  for (i = 0; i < NEWMV_MODE_CONTEXTS; ++i)
    av1_cond_prob_diff_update(w, &cm->fc->newmv_prob[i], counts->newmv_mode[i],
                              probwt);
  for (i = 0; i < ZEROMV_MODE_CONTEXTS; ++i)
    av1_cond_prob_diff_update(w, &cm->fc->zeromv_prob[i],
                              counts->zeromv_mode[i], probwt);
  for (i = 0; i < REFMV_MODE_CONTEXTS; ++i)
    av1_cond_prob_diff_update(w, &cm->fc->refmv_prob[i], counts->refmv_mode[i],
                              probwt);
  for (i = 0; i < DRL_MODE_CONTEXTS; ++i)
    av1_cond_prob_diff_update(w, &cm->fc->drl_prob[i], counts->drl_mode[i],
                              probwt);
}
#endif

static int write_skip(const AV1_COMMON *cm, const MACROBLOCKD *xd,
                      int segment_id, const MODE_INFO *mi, aom_writer *w) {
  if (segfeature_active(&cm->seg, segment_id, SEG_LVL_SKIP)) {
    return 1;
  } else {
    const int skip = mi->mbmi.skip;
#if CONFIG_NEW_MULTISYMBOL
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
    const int ctx = av1_get_skip_context(xd);
    aom_write_symbol(w, skip, ec_ctx->skip_cdfs[ctx], 2);
#else
    aom_write(w, skip, av1_get_skip_prob(cm, xd));
#endif
    return skip;
  }
}

static void write_is_inter(const AV1_COMMON *cm, const MACROBLOCKD *xd,
                           int segment_id, aom_writer *w, const int is_inter) {
  if (!segfeature_active(&cm->seg, segment_id, SEG_LVL_REF_FRAME)) {
#if CONFIG_NEW_MULTISYMBOL
    FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
    const int ctx = av1_get_intra_inter_context(xd);
    aom_write_symbol(w, is_inter, ec_ctx->intra_inter_cdf[ctx], 2);
#else
    aom_write(w, is_inter, av1_get_intra_inter_prob(cm, xd));
#endif
  }
}

#if CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
static void write_motion_mode(const AV1_COMMON *cm, MACROBLOCKD *xd,
                              const MODE_INFO *mi, aom_writer *w) {
  const MB_MODE_INFO *mbmi = &mi->mbmi;

#if !CONFIG_GLOBAL_MOTION
  // The cm parameter is only used with global_motion or with
  // motion_var and warped_motion. In other cases, explicitly ignore
  // it to avoid a compiler warning.
  (void)cm;
#endif

#if CONFIG_NCOBMC_ADAPT_WEIGHT
  MOTION_MODE last_motion_mode_allowed =
      motion_mode_allowed_wrapper(0,
#if CONFIG_GLOBAL_MOTION
                                  0, cm->global_motion,
#endif  // CONFIG_GLOBAL_MOTION
#if CONFIG_WARPED_MOTION
                                  xd,
#endif
                                  mi);
#else
  MOTION_MODE last_motion_mode_allowed = motion_mode_allowed(
#if CONFIG_GLOBAL_MOTION
      0, cm->global_motion,
#endif  // CONFIG_GLOBAL_MOTION
#if CONFIG_WARPED_MOTION
      xd,
#endif
      mi);
#endif  // CONFIG_NCOBMC_ADAPT_WEIGHT
  if (last_motion_mode_allowed == SIMPLE_TRANSLATION) return;
#if CONFIG_MOTION_VAR && CONFIG_WARPED_MOTION
  if (last_motion_mode_allowed == OBMC_CAUSAL) {
#if CONFIG_NEW_MULTISYMBOL
    aom_write_symbol(w, mbmi->motion_mode == OBMC_CAUSAL,
                     xd->tile_ctx->obmc_cdf[mbmi->sb_type], 2);
#else
    aom_write(w, mbmi->motion_mode == OBMC_CAUSAL,
              cm->fc->obmc_prob[mbmi->sb_type]);
#endif
  } else {
#endif  // CONFIG_MOTION_VAR && CONFIG_WARPED_MOTION
    aom_write_symbol(w, mbmi->motion_mode,
                     xd->tile_ctx->motion_mode_cdf[mbmi->sb_type],
                     MOTION_MODES);
#if CONFIG_MOTION_VAR && CONFIG_WARPED_MOTION
  }
#endif  // CONFIG_MOTION_VAR && CONFIG_WARPED_MOTION
}

#if CONFIG_NCOBMC_ADAPT_WEIGHT
static void write_ncobmc_mode(MACROBLOCKD *xd, const MODE_INFO *mi,
                              aom_writer *w) {
  const MB_MODE_INFO *mbmi = &mi->mbmi;
  ADAPT_OVERLAP_BLOCK ao_block = adapt_overlap_block_lookup[mbmi->sb_type];
  if (mbmi->motion_mode != NCOBMC_ADAPT_WEIGHT) return;

  aom_write_symbol(w, mbmi->ncobmc_mode[0],
                   xd->tile_ctx->ncobmc_mode_cdf[ao_block], MAX_NCOBMC_MODES);
  if (mi_size_wide[mbmi->sb_type] != mi_size_high[mbmi->sb_type]) {
    aom_write_symbol(w, mbmi->ncobmc_mode[1],
                     xd->tile_ctx->ncobmc_mode_cdf[ao_block], MAX_NCOBMC_MODES);
  }
}
#endif
#endif  // CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION

#if CONFIG_DELTA_Q
static void write_delta_qindex(const AV1_COMMON *cm, const MACROBLOCKD *xd,
                               int delta_qindex, aom_writer *w) {
  int sign = delta_qindex < 0;
  int abs = sign ? -delta_qindex : delta_qindex;
  int rem_bits, thr;
  int smallval = abs < DELTA_Q_SMALL ? 1 : 0;
  FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  (void)cm;

  aom_write_symbol(w, AOMMIN(abs, DELTA_Q_SMALL), ec_ctx->delta_q_cdf,
                   DELTA_Q_PROBS + 1);

  if (!smallval) {
    rem_bits = OD_ILOG_NZ(abs - 1) - 1;
    thr = (1 << rem_bits) + 1;
    aom_write_literal(w, rem_bits, 3);
    aom_write_literal(w, abs - thr, rem_bits);
  }
  if (abs > 0) {
    aom_write_bit(w, sign);
  }
}

#if CONFIG_EXT_DELTA_Q
static void write_delta_lflevel(const AV1_COMMON *cm, const MACROBLOCKD *xd,
                                int delta_lflevel, aom_writer *w) {
  int sign = delta_lflevel < 0;
  int abs = sign ? -delta_lflevel : delta_lflevel;
  int rem_bits, thr;
  int smallval = abs < DELTA_LF_SMALL ? 1 : 0;
  FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  (void)cm;

  aom_write_symbol(w, AOMMIN(abs, DELTA_LF_SMALL), ec_ctx->delta_lf_cdf,
                   DELTA_LF_PROBS + 1);

  if (!smallval) {
    rem_bits = OD_ILOG_NZ(abs - 1) - 1;
    thr = (1 << rem_bits) + 1;
    aom_write_literal(w, rem_bits, 3);
    aom_write_literal(w, abs - thr, rem_bits);
  }
  if (abs > 0) {
    aom_write_bit(w, sign);
  }
}
#endif  // CONFIG_EXT_DELTA_Q
#endif  // CONFIG_DELTA_Q

#if !CONFIG_NEW_MULTISYMBOL
static void update_skip_probs(AV1_COMMON *cm, aom_writer *w,
                              FRAME_COUNTS *counts) {
  int k;
  const int probwt = cm->num_tg;
  for (k = 0; k < SKIP_CONTEXTS; ++k) {
    av1_cond_prob_diff_update(w, &cm->fc->skip_probs[k], counts->skip[k],
                              probwt);
  }
}
#endif

#if CONFIG_PALETTE
static void pack_palette_tokens(aom_writer *w, const TOKENEXTRA **tp, int n,
                                int num) {
  const TOKENEXTRA *p = *tp;
  write_uniform(w, n, p->token);  // The first color index.
  ++p;
  --num;
  for (int i = 0; i < num; ++i) {
    aom_write_symbol(w, p->token, p->palette_cdf, n);
    ++p;
  }
  *tp = p;
}
#endif  // CONFIG_PALETTE

#if !CONFIG_PVQ
#if CONFIG_SUPERTX
static void update_supertx_probs(AV1_COMMON *cm, int probwt, aom_writer *w) {
  const int savings_thresh = av1_cost_one(GROUP_DIFF_UPDATE_PROB) -
                             av1_cost_zero(GROUP_DIFF_UPDATE_PROB);
  int i, j;
  int savings = 0;
  int do_update = 0;
  for (i = 0; i < PARTITION_SUPERTX_CONTEXTS; ++i) {
    for (j = TX_8X8; j < TX_SIZES; ++j) {
      savings += av1_cond_prob_diff_update_savings(
          &cm->fc->supertx_prob[i][j], cm->counts.supertx[i][j], probwt);
    }
  }
  do_update = savings > savings_thresh;
  aom_write(w, do_update, GROUP_DIFF_UPDATE_PROB);
  if (do_update) {
    for (i = 0; i < PARTITION_SUPERTX_CONTEXTS; ++i) {
      for (j = TX_8X8; j < TX_SIZES; ++j) {
        av1_cond_prob_diff_update(w, &cm->fc->supertx_prob[i][j],
                                  cm->counts.supertx[i][j], probwt);
      }
    }
  }
}
#endif  // CONFIG_SUPERTX

#if CONFIG_NEW_MULTISYMBOL
static INLINE void write_coeff_extra(const aom_cdf_prob *const *cdf, int val,
                                     int n, aom_writer *w) {
  // Code the extra bits from LSB to MSB in groups of 4
  int i = 0;
  int count = 0;
  while (count < n) {
    const int size = AOMMIN(n - count, 4);
    const int mask = (1 << size) - 1;
    aom_write_cdf(w, val & mask, cdf[i++], 1 << size);
    val >>= size;
    count += size;
  }
}
#else
static INLINE void write_coeff_extra(const aom_prob *pb, int value,
                                     int num_bits, int skip_bits, aom_writer *w,
                                     TOKEN_STATS *token_stats) {
  // Code the extra bits from MSB to LSB 1 bit at a time
  int index;
  for (index = skip_bits; index < num_bits; ++index) {
    const int shift = num_bits - index - 1;
    const int bb = (value >> shift) & 1;
    aom_write_record(w, bb, pb[index], token_stats);
  }
}
#endif

#if !CONFIG_LV_MAP
static void pack_mb_tokens(aom_writer *w, const TOKENEXTRA **tp,
                           const TOKENEXTRA *const stop,
                           aom_bit_depth_t bit_depth, const TX_SIZE tx_size,
                           TOKEN_STATS *token_stats) {
  const TOKENEXTRA *p = *tp;
#if CONFIG_VAR_TX
  int count = 0;
  const int seg_eob = tx_size_2d[tx_size];
#endif

  while (p < stop && p->token != EOSB_TOKEN) {
    const int token = p->token;
    const int eob_val = p->eob_val;
    if (token == BLOCK_Z_TOKEN) {
      aom_write_symbol(w, 0, *p->head_cdf, HEAD_TOKENS + 1);
      p++;
#if CONFIG_VAR_TX
      break;
#endif
      continue;
    }

    const av1_extra_bit *const extra_bits = &av1_extra_bits[token];
    if (eob_val == LAST_EOB) {
      // Just code a flag indicating whether the value is >1 or 1.
      aom_write_bit(w, token != ONE_TOKEN);
    } else {
      int comb_symb = 2 * AOMMIN(token, TWO_TOKEN) - eob_val + p->first_val;
      aom_write_symbol(w, comb_symb, *p->head_cdf, HEAD_TOKENS + p->first_val);
    }
    if (token > ONE_TOKEN) {
      aom_write_symbol(w, token - TWO_TOKEN, *p->tail_cdf, TAIL_TOKENS);
    }

    if (extra_bits->base_val) {
      const int bit_string = p->extra;
      const int bit_string_length = extra_bits->len;  // Length of extra bits to
      const int is_cat6 = (extra_bits->base_val == CAT6_MIN_VAL);
      // be written excluding
      // the sign bit.
      int skip_bits = is_cat6
                          ? (int)sizeof(av1_cat6_prob) -
                                av1_get_cat6_extrabits_size(tx_size, bit_depth)
                          : 0;

      assert(!(bit_string >> (bit_string_length - skip_bits + 1)));
      if (bit_string_length > 0)
#if CONFIG_NEW_MULTISYMBOL
        write_coeff_extra(extra_bits->cdf, bit_string >> 1,
                          bit_string_length - skip_bits, w);
#else
        write_coeff_extra(extra_bits->prob, bit_string >> 1, bit_string_length,
                          skip_bits, w, token_stats);
#endif

      aom_write_bit_record(w, bit_string & 1, token_stats);
    }
    ++p;

#if CONFIG_VAR_TX
    ++count;
    if (eob_val == EARLY_EOB || count == seg_eob) break;
#endif
  }

  *tp = p;
}
#endif  // !CONFIG_LV_MAP
#else   // !CONFIG_PVQ
static PVQ_INFO *get_pvq_block(PVQ_QUEUE *pvq_q) {
  PVQ_INFO *pvq;

  assert(pvq_q->curr_pos <= pvq_q->last_pos);
  assert(pvq_q->curr_pos < pvq_q->buf_len);

  pvq = pvq_q->buf + pvq_q->curr_pos;
  ++pvq_q->curr_pos;

  return pvq;
}

static void pack_pvq_tokens(aom_writer *w, MACROBLOCK *const x,
                            MACROBLOCKD *const xd, int plane, BLOCK_SIZE bsize,
                            const TX_SIZE tx_size) {
  PVQ_INFO *pvq;
  int idx, idy;
  const struct macroblockd_plane *const pd = &xd->plane[plane];
  od_adapt_ctx *adapt;
  int max_blocks_wide;
  int max_blocks_high;
  int step = (1 << tx_size);

#if CONFIG_CHROMA_SUB8X8
  const BLOCK_SIZE plane_bsize =