bitstream.c 163 KB
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/*
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 * Copyright (c) 2016, Alliance for Open Media. All rights reserved
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 *
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 * 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.
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 */

#include <assert.h>
#include <limits.h>
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#include <stdio.h>
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#include "aom/aom_encoder.h"
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#include "aom_dsp/bitwriter_buffer.h"
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#include "aom_dsp/aom_dsp_common.h"
#include "aom_mem/aom_mem.h"
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#include "aom_ports/mem_ops.h"
#include "aom_ports/system_state.h"
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#if CONFIG_BITSTREAM_DEBUG
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#include "aom_util/debug_util.h"
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#endif  // CONFIG_BITSTREAM_DEBUG
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#if CONFIG_CLPF
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#include "av1/common/clpf.h"
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#endif
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#if CONFIG_DERING
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#include "av1/common/dering.h"
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#endif  // CONFIG_DERING
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#include "av1/common/entropy.h"
#include "av1/common/entropymode.h"
#include "av1/common/entropymv.h"
#include "av1/common/mvref_common.h"
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#include "av1/common/odintrin.h"
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#include "av1/common/pred_common.h"
#include "av1/common/reconinter.h"
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#if CONFIG_EXT_INTRA
#include "av1/common/reconintra.h"
#endif  // CONFIG_EXT_INTRA
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#include "av1/common/seg_common.h"
#include "av1/common/tile_common.h"
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#if CONFIG_ANS
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#include "aom_dsp/buf_ans.h"
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#endif  // CONFIG_ANS
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#include "av1/encoder/bitstream.h"
#include "av1/encoder/cost.h"
#include "av1/encoder/encodemv.h"
#include "av1/encoder/mcomp.h"
#include "av1/encoder/segmentation.h"
#include "av1/encoder/subexp.h"
#include "av1/encoder/tokenize.h"
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#if CONFIG_PVQ
#include "av1/encoder/pvq_encoder.h"
#endif
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static struct av1_token intra_mode_encodings[INTRA_MODES];
static struct av1_token switchable_interp_encodings[SWITCHABLE_FILTERS];
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#if CONFIG_EXT_PARTITION_TYPES
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static const struct av1_token ext_partition_encodings[EXT_PARTITION_TYPES] = {
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  { 0, 1 },  { 4, 3 },  { 12, 4 }, { 7, 3 },
  { 10, 4 }, { 11, 4 }, { 26, 5 }, { 27, 5 }
};
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#endif
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static struct av1_token partition_encodings[PARTITION_TYPES];
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#if !CONFIG_REF_MV
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static struct av1_token inter_mode_encodings[INTER_MODES];
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#endif
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#if CONFIG_EXT_INTER
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static const struct av1_token
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    inter_compound_mode_encodings[INTER_COMPOUND_MODES] = {
      { 2, 2 },  { 50, 6 }, { 51, 6 }, { 24, 5 }, { 52, 6 },
      { 53, 6 }, { 54, 6 }, { 55, 6 }, { 0, 1 },  { 7, 3 }
    };
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#endif  // CONFIG_EXT_INTER
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#if CONFIG_PALETTE
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static struct av1_token palette_size_encodings[PALETTE_MAX_SIZE - 1];
static struct av1_token palette_color_encodings[PALETTE_MAX_SIZE - 1]
                                               [PALETTE_MAX_SIZE];
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#endif  // CONFIG_PALETTE
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static const struct av1_token tx_size_encodings[MAX_TX_DEPTH][TX_SIZES] = {
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  { { 0, 1 }, { 1, 1 } },                      // Max tx_size is 8X8
  { { 0, 1 }, { 2, 2 }, { 3, 2 } },            // Max tx_size is 16X16
  { { 0, 1 }, { 2, 2 }, { 6, 3 }, { 7, 3 } },  // Max tx_size is 32X32
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#if CONFIG_TX64X64
  { { 0, 1 }, { 2, 2 }, { 6, 3 }, { 14, 4 }, { 15, 4 } },  // Max tx_size 64X64
#endif                                                     // CONFIG_TX64X64
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};

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#if CONFIG_EXT_INTRA || CONFIG_FILTER_INTRA || CONFIG_PALETTE
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static INLINE void write_uniform(aom_writer *w, int n, int v) {
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  int l = get_unsigned_bits(n);
  int m = (1 << l) - n;
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  if (l == 0) return;
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  if (v < m) {
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    aom_write_literal(w, v, l - 1);
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  } else {
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    aom_write_literal(w, m + ((v - m) >> 1), l - 1);
    aom_write_literal(w, (v - m) & 1, 1);
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  }
}
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#endif  // CONFIG_EXT_INTRA || CONFIG_FILTER_INTRA || CONFIG_PALETTE
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#if CONFIG_EXT_TX
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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];
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#else
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static struct av1_token ext_tx_encodings[TX_TYPES];
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#endif  // CONFIG_EXT_TX
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#if CONFIG_GLOBAL_MOTION
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static struct av1_token global_motion_types_encodings[GLOBAL_TRANS_TYPES];
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#endif  // CONFIG_GLOBAL_MOTION
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#if CONFIG_EXT_INTRA
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#if CONFIG_INTRA_INTERP
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static struct av1_token intra_filter_encodings[INTRA_FILTERS];
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#endif  // CONFIG_INTRA_INTERP
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#endif  // CONFIG_EXT_INTRA
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#if CONFIG_EXT_INTER
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static struct av1_token interintra_mode_encodings[INTERINTRA_MODES];
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static struct av1_token compound_type_encodings[COMPOUND_TYPES];
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#endif  // CONFIG_EXT_INTER
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#if CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
static struct av1_token motion_mode_encodings[MOTION_MODES];
#endif  // CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
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#if CONFIG_LOOP_RESTORATION
static struct av1_token switchable_restore_encodings[RESTORE_SWITCHABLE_TYPES];
#endif  // CONFIG_LOOP_RESTORATION
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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);
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void av1_encode_token_init(void) {
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#if CONFIG_EXT_TX || CONFIG_PALETTE
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  int s;
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#endif  // CONFIG_EXT_TX || CONFIG_PALETTE
#if CONFIG_EXT_TX
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  for (s = 1; s < EXT_TX_SETS_INTER; ++s) {
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    av1_tokens_from_tree(ext_tx_inter_encodings[s], av1_ext_tx_inter_tree[s]);
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  }
  for (s = 1; s < EXT_TX_SETS_INTRA; ++s) {
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    av1_tokens_from_tree(ext_tx_intra_encodings[s], av1_ext_tx_intra_tree[s]);
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  }
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#else
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  av1_tokens_from_tree(ext_tx_encodings, av1_ext_tx_tree);
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#endif  // CONFIG_EXT_TX
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  av1_tokens_from_tree(intra_mode_encodings, av1_intra_mode_tree);
  av1_tokens_from_tree(switchable_interp_encodings, av1_switchable_interp_tree);
  av1_tokens_from_tree(partition_encodings, av1_partition_tree);
#if !CONFIG_REF_MV
  av1_tokens_from_tree(inter_mode_encodings, av1_inter_mode_tree);
#endif

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#if CONFIG_PALETTE
  av1_tokens_from_tree(palette_size_encodings, av1_palette_size_tree);
  for (s = 0; s < PALETTE_MAX_SIZE - 1; ++s) {
    av1_tokens_from_tree(palette_color_encodings[s], av1_palette_color_tree[s]);
  }
#endif  // CONFIG_PALETTE

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#if CONFIG_EXT_INTRA
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#if CONFIG_INTRA_INTERP
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  av1_tokens_from_tree(intra_filter_encodings, av1_intra_filter_tree);
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#endif  // CONFIG_INTRA_INTERP
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#endif  // CONFIG_EXT_INTRA
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#if CONFIG_EXT_INTER
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  av1_tokens_from_tree(interintra_mode_encodings, av1_interintra_mode_tree);
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  av1_tokens_from_tree(compound_type_encodings, av1_compound_type_tree);
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#endif  // CONFIG_EXT_INTER
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#if CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
  av1_tokens_from_tree(motion_mode_encodings, av1_motion_mode_tree);
#endif  // CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
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#if CONFIG_GLOBAL_MOTION
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  av1_tokens_from_tree(global_motion_types_encodings,
                       av1_global_motion_types_tree);
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#endif  // CONFIG_GLOBAL_MOTION
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#if CONFIG_LOOP_RESTORATION
  av1_tokens_from_tree(switchable_restore_encodings,
                       av1_switchable_restore_tree);
#endif  // CONFIG_LOOP_RESTORATION
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#if CONFIG_EC_MULTISYMBOL
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  /* This hack is necessary when CONFIG_EXT_INTERP 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,
                        SWITCHABLE_FILTERS, av1_switchable_interp_tree);
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/* 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. */
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#if !CONFIG_EXT_TX
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  av1_indices_from_tree(av1_ext_tx_ind, av1_ext_tx_inv, TX_TYPES,
                        av1_ext_tx_tree);
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#endif
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#endif
#if CONFIG_DAALA_EC
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  av1_indices_from_tree(av1_intra_mode_ind, av1_intra_mode_inv, INTRA_MODES,
                        av1_intra_mode_tree);
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  av1_indices_from_tree(av1_inter_mode_ind, av1_inter_mode_inv, INTER_MODES,
                        av1_inter_mode_tree);
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#endif
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}

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#if !CONFIG_DAALA_EC
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static void write_intra_mode(aom_writer *w, PREDICTION_MODE mode,
                             const aom_prob *probs) {
  av1_write_token(w, av1_intra_mode_tree, probs, &intra_mode_encodings[mode]);
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}
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#endif
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#if CONFIG_EXT_INTER
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static void write_interintra_mode(aom_writer *w, INTERINTRA_MODE mode,
                                  const aom_prob *probs) {
  av1_write_token(w, av1_interintra_mode_tree, probs,
                  &interintra_mode_encodings[mode]);
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}
#endif  // CONFIG_EXT_INTER

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static void write_inter_mode(AV1_COMMON *cm, aom_writer *w,
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                             PREDICTION_MODE mode,
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#if CONFIG_REF_MV && CONFIG_EXT_INTER
                             int is_compound,
#endif  // CONFIG_REF_MV && CONFIG_EXT_INTER
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                             const int16_t mode_ctx) {
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#if CONFIG_REF_MV
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  const int16_t newmv_ctx = mode_ctx & NEWMV_CTX_MASK;
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  const aom_prob newmv_prob = cm->fc->newmv_prob[newmv_ctx];
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#if CONFIG_EXT_INTER
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  aom_write(w, mode != NEWMV && mode != NEWFROMNEARMV, newmv_prob);
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  if (!is_compound && (mode == NEWMV || mode == NEWFROMNEARMV))
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    aom_write(w, mode == NEWFROMNEARMV, cm->fc->new2mv_prob);
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  if (mode != NEWMV && mode != NEWFROMNEARMV) {
#else
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  aom_write(w, mode != NEWMV, newmv_prob);
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  if (mode != NEWMV) {
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#endif  // CONFIG_EXT_INTER
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    const int16_t zeromv_ctx = (mode_ctx >> ZEROMV_OFFSET) & ZEROMV_CTX_MASK;
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    const aom_prob zeromv_prob = cm->fc->zeromv_prob[zeromv_ctx];
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    if (mode_ctx & (1 << ALL_ZERO_FLAG_OFFSET)) {
      assert(mode == ZEROMV);
      return;
    }

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    aom_write(w, mode != ZEROMV, zeromv_prob);
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    if (mode != ZEROMV) {
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      int16_t refmv_ctx = (mode_ctx >> REFMV_OFFSET) & REFMV_CTX_MASK;
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      aom_prob refmv_prob;
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      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;
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      refmv_prob = cm->fc->refmv_prob[refmv_ctx];
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      aom_write(w, mode != NEARESTMV, refmv_prob);
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    }
  }
#else
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  assert(is_inter_mode(mode));
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#if CONFIG_DAALA_EC
  aom_write_symbol(w, av1_inter_mode_ind[INTER_OFFSET(mode)],
                   cm->fc->inter_mode_cdf[mode_ctx], INTER_MODES);
#else
  {
    const aom_prob *const inter_probs = cm->fc->inter_mode_probs[mode_ctx];
    av1_write_token(w, av1_inter_mode_tree, inter_probs,
                    &inter_mode_encodings[INTER_OFFSET(mode)]);
  }
#endif
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#endif
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}

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#if CONFIG_REF_MV
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static void write_drl_idx(const AV1_COMMON *cm, 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);
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  assert(mbmi->ref_mv_idx < 3);

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  if (mbmi->mode == NEWMV) {
    int idx;
    for (idx = 0; idx < 2; ++idx) {
      if (mbmi_ext->ref_mv_count[ref_frame_type] > idx + 1) {
        uint8_t drl_ctx =
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            av1_drl_ctx(mbmi_ext->ref_mv_stack[ref_frame_type], idx);
        aom_prob drl_prob = cm->fc->drl_prob[drl_ctx];
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        aom_write(w, mbmi->ref_mv_idx != idx, drl_prob);
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        if (mbmi->ref_mv_idx == idx) return;
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      }
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    }
    return;
  }

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  if (mbmi->mode == NEARMV) {
    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 =
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            av1_drl_ctx(mbmi_ext->ref_mv_stack[ref_frame_type], idx);
        aom_prob drl_prob = cm->fc->drl_prob[drl_ctx];
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        aom_write(w, mbmi->ref_mv_idx != (idx - 1), drl_prob);
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        if (mbmi->ref_mv_idx == (idx - 1)) return;
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      }
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    }
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    return;
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  }
}
#endif

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#if CONFIG_EXT_INTER
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static void write_inter_compound_mode(AV1_COMMON *cm, aom_writer *w,
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                                      PREDICTION_MODE mode,
                                      const int16_t mode_ctx) {
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  const aom_prob *const inter_compound_probs =
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      cm->fc->inter_compound_mode_probs[mode_ctx];
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  assert(is_inter_compound_mode(mode));
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  av1_write_token(w, av1_inter_compound_mode_tree, inter_compound_probs,
                  &inter_compound_mode_encodings[INTER_COMPOUND_OFFSET(mode)]);
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}
#endif  // CONFIG_EXT_INTER

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

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

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

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  av1_tree_probs_from_distribution(tree, branch_ct, counts);
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  for (i = 0; i < n - 1; ++i)
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    av1_cond_prob_diff_update(w, &probs[i], branch_ct[i], probwt);
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}
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#if CONFIG_EXT_INTER || CONFIG_EXT_TX || !CONFIG_EC_ADAPT
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static int prob_diff_update_savings(const aom_tree_index *tree,
                                    aom_prob probs[/*n - 1*/],
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                                    const unsigned int counts[/*n - 1*/], int n,
                                    int probwt) {
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  int i;
  unsigned int branch_ct[32][2];
  int savings = 0;

  // Assuming max number of probabilities <= 32
  assert(n <= 32);
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  av1_tree_probs_from_distribution(tree, branch_ct, counts);
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  for (i = 0; i < n - 1; ++i) {
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    savings +=
        av1_cond_prob_diff_update_savings(&probs[i], branch_ct[i], probwt);
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  }
  return savings;
}
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#endif  // CONFIG_EXT_INTER || CONFIG_EXT_TX || !CONFIG_EC_ADAPT
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#if CONFIG_VAR_TX
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static void write_tx_size_vartx(const AV1_COMMON *cm, const MACROBLOCKD *xd,
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                                const MB_MODE_INFO *mbmi, TX_SIZE tx_size,
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                                int depth, int blk_row, int blk_col,
                                aom_writer *w) {
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  const int tx_row = blk_row >> 1;
  const int tx_col = blk_col >> 1;
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  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);

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  int ctx = txfm_partition_context(xd->above_txfm_context + tx_col,
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                                   xd->left_txfm_context + tx_row,
                                   mbmi->sb_type, tx_size);
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  if (blk_row >= max_blocks_high || blk_col >= max_blocks_wide) return;
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  if (depth == MAX_VARTX_DEPTH) {
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    txfm_partition_update(xd->above_txfm_context + tx_col,
                          xd->left_txfm_context + tx_row, tx_size);
    return;
  }

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  if (tx_size == mbmi->inter_tx_size[tx_row][tx_col]) {
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    aom_write(w, 0, cm->fc->txfm_partition_prob[ctx]);
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    txfm_partition_update(xd->above_txfm_context + tx_col,
                          xd->left_txfm_context + tx_row, tx_size);
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  } else {
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    const TX_SIZE sub_txs = sub_tx_size_map[tx_size];
    const int bsl = tx_size_wide_unit[sub_txs];
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    int i;
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    aom_write(w, 1, cm->fc->txfm_partition_prob[ctx]);
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    if (tx_size == TX_8X8) {
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      txfm_partition_update(xd->above_txfm_context + tx_col,
                            xd->left_txfm_context + tx_row, TX_4X4);
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      return;
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    }
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    assert(bsl > 0);
    for (i = 0; i < 4; ++i) {
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      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);
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    }
  }
}
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static void update_txfm_partition_probs(AV1_COMMON *cm, aom_writer *w,
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                                        FRAME_COUNTS *counts, int probwt) {
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  int k;
  for (k = 0; k < TXFM_PARTITION_CONTEXTS; ++k)
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    av1_cond_prob_diff_update(w, &cm->fc->txfm_partition_prob[k],
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                              counts->txfm_partition[k], probwt);
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}
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#endif

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static void write_selected_tx_size(const AV1_COMMON *cm, const MACROBLOCKD *xd,
                                   aom_writer *w) {
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  const MB_MODE_INFO *const mbmi = &xd->mi[0]->mbmi;
  const BLOCK_SIZE bsize = mbmi->sb_type;
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  // For sub8x8 blocks the tx_size symbol does not need to be sent
  if (bsize >= BLOCK_8X8) {
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    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];
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    const int depth = tx_size_to_depth(coded_tx_size);
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#if CONFIG_EXT_TX && CONFIG_RECT_TX
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    assert(IMPLIES(is_rect_tx(tx_size), is_rect_tx_allowed(xd, mbmi)));
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    assert(
        IMPLIES(is_rect_tx(tx_size), tx_size == max_txsize_rect_lookup[bsize]));
#endif  // CONFIG_EXT_TX && CONFIG_RECT_TX

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    av1_write_token(w, av1_tx_size_tree[tx_size_cat],
                    cm->fc->tx_size_probs[tx_size_cat][tx_size_ctx],
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                    &tx_size_encodings[tx_size_cat][depth]);
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  }
}

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#if CONFIG_REF_MV
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static void update_inter_mode_probs(AV1_COMMON *cm, aom_writer *w,
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                                    FRAME_COUNTS *counts) {
  int i;
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#if CONFIG_TILE_GROUPS
  const int probwt = cm->num_tg;
#else
  const int probwt = 1;
#endif
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  for (i = 0; i < NEWMV_MODE_CONTEXTS; ++i)
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    av1_cond_prob_diff_update(w, &cm->fc->newmv_prob[i], counts->newmv_mode[i],
                              probwt);
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  for (i = 0; i < ZEROMV_MODE_CONTEXTS; ++i)
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    av1_cond_prob_diff_update(w, &cm->fc->zeromv_prob[i],
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                              counts->zeromv_mode[i], probwt);
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  for (i = 0; i < REFMV_MODE_CONTEXTS; ++i)
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    av1_cond_prob_diff_update(w, &cm->fc->refmv_prob[i], counts->refmv_mode[i],
                              probwt);
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  for (i = 0; i < DRL_MODE_CONTEXTS; ++i)
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    av1_cond_prob_diff_update(w, &cm->fc->drl_prob[i], counts->drl_mode[i],
                              probwt);
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#if CONFIG_EXT_INTER
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  av1_cond_prob_diff_update(w, &cm->fc->new2mv_prob, counts->new2mv_mode,
                            probwt);
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#endif  // CONFIG_EXT_INTER
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}
#endif

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#if CONFIG_EXT_INTER
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static void update_inter_compound_mode_probs(AV1_COMMON *cm, int probwt,
                                             aom_writer *w) {
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  const int savings_thresh = av1_cost_one(GROUP_DIFF_UPDATE_PROB) -
                             av1_cost_zero(GROUP_DIFF_UPDATE_PROB);
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  int i;
  int savings = 0;
  int do_update = 0;
  for (i = 0; i < INTER_MODE_CONTEXTS; ++i) {
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    savings += prob_diff_update_savings(
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        av1_inter_compound_mode_tree, cm->fc->inter_compound_mode_probs[i],
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        cm->counts.inter_compound_mode[i], INTER_COMPOUND_MODES, probwt);
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  }
  do_update = savings > savings_thresh;
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  aom_write(w, do_update, GROUP_DIFF_UPDATE_PROB);
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  if (do_update) {
    for (i = 0; i < INTER_MODE_CONTEXTS; ++i) {
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      prob_diff_update(
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          av1_inter_compound_mode_tree, cm->fc->inter_compound_mode_probs[i],
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          cm->counts.inter_compound_mode[i], INTER_COMPOUND_MODES, probwt, w);
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    }
  }
}
#endif  // CONFIG_EXT_INTER

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static int write_skip(const AV1_COMMON *cm, const MACROBLOCKD *xd,
                      int segment_id, const MODE_INFO *mi, aom_writer *w) {
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  if (segfeature_active(&cm->seg, segment_id, SEG_LVL_SKIP)) {
    return 1;
  } else {
    const int skip = mi->mbmi.skip;
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    aom_write(w, skip, av1_get_skip_prob(cm, xd));
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    return skip;
  }
}

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#if CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION
static void write_motion_mode(const AV1_COMMON *cm, const MB_MODE_INFO *mbmi,
                              aom_writer *w) {
  MOTION_MODE last_motion_mode_allowed = motion_mode_allowed(mbmi);

  if (last_motion_mode_allowed == SIMPLE_TRANSLATION) return;
#if CONFIG_MOTION_VAR && CONFIG_WARPED_MOTION
  if (last_motion_mode_allowed == OBMC_CAUSAL) {
    aom_write(w, mbmi->motion_mode == OBMC_CAUSAL,
              cm->fc->obmc_prob[mbmi->sb_type]);
  } else {
#endif  // CONFIG_MOTION_VAR && CONFIG_WARPED_MOTION
    av1_write_token(w, av1_motion_mode_tree,
                    cm->fc->motion_mode_prob[mbmi->sb_type],
                    &motion_mode_encodings[mbmi->motion_mode]);
#if CONFIG_MOTION_VAR && CONFIG_WARPED_MOTION
  }
#endif  // CONFIG_MOTION_VAR && CONFIG_WARPED_MOTION
}
#endif  // CONFIG_MOTION_VAR || CONFIG_WARPED_MOTION

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

  while (i < DELTA_Q_SMALL && i <= abs) {
    int bit = (i < abs);
    aom_write(w, bit, cm->fc->delta_q_prob[i]);
    i++;
  }

  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);
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  }
  if (abs > 0) {
    aom_write_bit(w, sign);
  }
}
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static void update_delta_q_probs(AV1_COMMON *cm, aom_writer *w,
                                 FRAME_COUNTS *counts) {
  int k;
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#if CONFIG_TILE_GROUPS
  const int probwt = cm->num_tg;
#else
  const int probwt = 1;
#endif
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  for (k = 0; k < DELTA_Q_CONTEXTS; ++k) {
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    av1_cond_prob_diff_update(w, &cm->fc->delta_q_prob[k], counts->delta_q[k],
                              probwt);
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  }
}
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#endif

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static void update_skip_probs(AV1_COMMON *cm, aom_writer *w,
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                              FRAME_COUNTS *counts) {
  int k;
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#if CONFIG_TILE_GROUPS
  const int probwt = cm->num_tg;
#else
  const int probwt = 1;
#endif
  for (k = 0; k < SKIP_CONTEXTS; ++k) {
    av1_cond_prob_diff_update(w, &cm->fc->skip_probs[k], counts->skip[k],
                              probwt);
  }
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}

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#if !CONFIG_EC_ADAPT
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static void update_switchable_interp_probs(AV1_COMMON *cm, aom_writer *w,
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                                           FRAME_COUNTS *counts) {
  int j;
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  for (j = 0; j < SWITCHABLE_FILTER_CONTEXTS; ++j) {
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#if CONFIG_TILE_GROUPS
    const int probwt = cm->num_tg;
#else
    const int probwt = 1;
#endif
    prob_diff_update(
        av1_switchable_interp_tree, cm->fc->switchable_interp_prob[j],
        counts->switchable_interp[j], SWITCHABLE_FILTERS, probwt, w);
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  }
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}
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#endif
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#if CONFIG_EXT_TX
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static void update_ext_tx_probs(AV1_COMMON *cm, aom_writer *w) {
  const int savings_thresh = av1_cost_one(GROUP_DIFF_UPDATE_PROB) -
                             av1_cost_zero(GROUP_DIFF_UPDATE_PROB);
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  int i, j;
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  int s;
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#if CONFIG_TILE_GROUPS
  const int probwt = cm->num_tg;
#else
  const int probwt = 1;
#endif
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  for (s = 1; s < EXT_TX_SETS_INTER; ++s) {
    int savings = 0;
    int do_update = 0;
    for (i = TX_4X4; i < EXT_TX_SIZES; ++i) {
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      if (!use_inter_ext_tx_for_txsize[s][i]) continue;
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      savings += prob_diff_update_savings(
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          av1_ext_tx_inter_tree[s], cm->fc->inter_ext_tx_prob[s][i],
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          cm->counts.inter_ext_tx[s][i], num_ext_tx_set_inter[s], probwt);
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    }
    do_update = savings > savings_thresh;
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    aom_write(w, do_update, GROUP_DIFF_UPDATE_PROB);
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    if (do_update) {
      for (i = TX_4X4; i < EXT_TX_SIZES; ++i) {
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        if (!use_inter_ext_tx_for_txsize[s][i]) continue;
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        prob_diff_update(
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            av1_ext_tx_inter_tree[s], cm->fc->inter_ext_tx_prob[s][i],
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            cm->counts.inter_ext_tx[s][i], num_ext_tx_set_inter[s], probwt, w);
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      }
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    }
  }
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  for (s = 1; s < EXT_TX_SETS_INTRA; ++s) {
    int savings = 0;
    int do_update = 0;
    for (i = TX_4X4; i < EXT_TX_SIZES; ++i) {
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      if (!use_intra_ext_tx_for_txsize[s][i]) continue;
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      for (j = 0; j < INTRA_MODES; ++j)
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        savings += prob_diff_update_savings(
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            av1_ext_tx_intra_tree[s], cm->fc->intra_ext_tx_prob[s][i][j],
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            cm->counts.intra_ext_tx[s][i][j], num_ext_tx_set_intra[s], probwt);
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    }
    do_update = savings > savings_thresh;
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    aom_write(w, do_update, GROUP_DIFF_UPDATE_PROB);
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    if (do_update) {
      for (i = TX_4X4; i < EXT_TX_SIZES; ++i) {
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        if (!use_intra_ext_tx_for_txsize[s][i]) continue;
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        for (j = 0; j < INTRA_MODES; ++j)
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          prob_diff_update(av1_ext_tx_intra_tree[s],
                           cm->fc->intra_ext_tx_prob[s][i][j],
                           cm->counts.intra_ext_tx[s][i][j],
                           num_ext_tx_set_intra[s], probwt, w);
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      }
    }
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  }
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}
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#else
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#if !CONFIG_EC_ADAPT
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static void update_ext_tx_probs(AV1_COMMON *cm, aom_writer *w) {
  const int savings_thresh = av1_cost_one(GROUP_DIFF_UPDATE_PROB) -
                             av1_cost_zero(GROUP_DIFF_UPDATE_PROB);
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  int i, j;

  int savings = 0;
  int do_update = 0;
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#if CONFIG_TILE_GROUPS
  const int probwt = cm->num_tg;
#else
  const int probwt = 1;
#endif
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  for (i = TX_4X4; i < EXT_TX_SIZES; ++i) {
    for (j = 0; j < TX_TYPES; ++j)
      savings += prob_diff_update_savings(
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          av1_ext_tx_tree, cm->fc->intra_ext_tx_prob[i][j],
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          cm->counts.intra_ext_tx[i][j], TX_TYPES, probwt);
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  }
  do_update = savings > savings_thresh;
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  aom_write(w, do_update, GROUP_DIFF_UPDATE_PROB);
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  if (do_update) {
    for (i = TX_4X4; i < EXT_TX_SIZES; ++i) {
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      for (j = 0; j < TX_TYPES; ++j) {
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        prob_diff_update(av1_ext_tx_tree, cm->fc->intra_ext_tx_prob[i][j],
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                         cm->counts.intra_ext_tx[i][j], TX_TYPES, probwt, w);
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      }
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    }
  }
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  savings = 0;
  for (i = TX_4X4; i < EXT_TX_SIZES; ++i) {
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    savings +=
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        prob_diff_update_savings(av1_ext_tx_tree, cm->fc->inter_ext_tx_prob[i],
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                                 cm->counts.inter_ext_tx[i], TX_TYPES, probwt);
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  }
  do_update = savings > savings_thresh;
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  aom_write(w, do_update, GROUP_DIFF_UPDATE_PROB);
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  if (do_update) {
    for (i = TX_4X4; i < EXT_TX_SIZES; ++i) {
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      prob_diff_update(av1_ext_tx_tree, cm->fc->inter_ext_tx_prob[i],
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                       cm->counts.inter_ext_tx[i], TX_TYPES, probwt, w);
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    }
  }
}
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#endif  // CONFIG_EXT_TX
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#endif
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#if CONFIG_PALETTE
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static void pack_palette_tokens(aom_writer *w, const TOKENEXTRA **tp, int n,
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                                int num) {
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  int i;
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  const TOKENEXTRA *p = *tp;
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  for (i = 0; i < num; ++i) {
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    av1_write_token(w, av1_palette_color_tree[n - 2], p->context_tree,
                    &palette_color_encodings[n - 2][p->token]);
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    ++p;
  }

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

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static void pack_mb_tokens(aom_writer *w, const TOKENEXTRA **tp,
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                           const TOKENEXTRA *const stop,
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                           aom_bit_depth_t bit_depth, const TX_SIZE tx_size,
                           TOKEN_STATS *token_stats) {
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  const TOKENEXTRA *p = *tp;
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#if CONFIG_VAR_TX
  int count = 0;
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  const int seg_eob = tx_size_2d[tx_size];
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#endif
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#if CONFIG_AOM_HIGHBITDEPTH
  const av1_extra_bit *const extra_bits_table =
      (bit_depth == AOM_BITS_12)
          ? av1_extra_bits_high12
          : (bit_depth == AOM_BITS_10) ? av1_extra_bits_high10 : av1_extra_bits;
#else
  const av1_extra_bit *const extra_bits_table = av1_extra_bits;
  (void)bit_depth;
#endif  // CONFIG_AOM_HIGHBITDEPTH
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  while (p < stop && p->token != EOSB_TOKEN) {
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    const int token = p->token;
    aom_tree_index index = 0;
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#if !CONFIG_EC_MULTISYMBOL
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    const struct av1_token *const coef_encoding = &av1_coef_encodings[token];
    int coef_value = coef_encoding->value;
    int coef_length = coef_encoding->len;
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#endif  // !CONFIG_EC_MULTISYMBOL
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    const av1_extra_bit *const extra_bits = &extra_bits_table[token];
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#if CONFIG_EC_MULTISYMBOL
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    /* skip one or two nodes */
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    if (!p->skip_eob_node)
      aom_write_record(w, token != EOB_TOKEN, p->context_tree[0], token_stats);
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    if (token != EOB_TOKEN) {
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      aom_write_record(w, token != ZERO_TOKEN, p->context_tree[1], token_stats);
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      if (token != ZERO_TOKEN) {
        aom_write_symbol(w, token - ONE_TOKEN, *p->token_cdf,
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                         CATEGORY6_TOKEN - ONE_TOKEN + 1);
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      }
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    }
#else
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    /* skip one or two nodes */
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    if (p->skip_eob_node)
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      coef_length -= p->skip_eob_node;
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    else
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      aom_write_record(w, token != EOB_TOKEN, p->context_tree[0], token_stats);
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    if (token != EOB_TOKEN) {
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      aom_write_record(w, token != ZERO_TOKEN, p->context_tree[1], token_stats);
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      if (token != ZERO_TOKEN) {
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        aom_write_record(w, token != ONE_TOKEN, p->context_tree[2],
                         token_stats);
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        if (token != ONE_TOKEN) {
          const int unconstrained_len = UNCONSTRAINED_NODES - p->skip_eob_node;
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          aom_write_tree_record(
              w, av1_coef_con_tree,
              av1_pareto8_full[p->context_tree[PIVOT_NODE] - 1], coef_value,
              coef_length - unconstrained_len, 0, token_stats);
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        }
      }
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    }
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#endif  // CONFIG_EC_MULTISYMBOL
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    if (extra_bits->base_val) {
      const int bit_string = p->extra;
      const int bit_string_length = extra_bits->len;  // Length of extra bits to
                                                      // be written excluding
                                                      // the sign bit.
      int skip_bits = (extra_bits->base_val == CAT6_MIN_VAL)
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                          ? TX_SIZES - 1 - txsize_sqr_up_map[tx_size]
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                          : 0;
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      if (bit_string_length > 0) {
        const unsigned char *pb = extra_bits->prob;
        const int value = bit_string >> 1;
        const int num_bits = bit_string_length;  // number of bits in value
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        assert(num_bits > 0);