/*

 *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.

 *

 *  Use of this source code is governed by a BSD-style license

 *  that can be found in the LICENSE file in the root of the source

 *  tree. An additional intellectual property rights grant can be found

 *  in the file PATENTS.  All contributing project authors may

 *  be found in the AUTHORS file in the root of the source tree.

 */

#include <assert.h>

#include <stdint.h>

#include <stdio.h>

#include <limits.h>

#include "vpx/vpx_encoder.h"

#include "vpx_dsp/bitwriter_buffer.h"

#include "vpx_dsp/vpx_dsp_common.h"

#include "vpx_mem/vpx_mem.h"

#include "vpx_ports/mem_ops.h"

#include "vpx_ports/system_state.h"

#if CONFIG_BITSTREAM_DEBUG

#include "vpx_util/vpx_debug_util.h"

#endif  // CONFIG_BITSTREAM_DEBUG

#include "vp9/common/vp9_entropy.h"

#include "vp9/common/vp9_entropymode.h"

#include "vp9/common/vp9_entropymv.h"

#include "vp9/common/vp9_mvref_common.h"

#include "vp9/common/vp9_pred_common.h"

#include "vp9/common/vp9_seg_common.h"

#include "vp9/common/vp9_tile_common.h"

#include "vp9/encoder/vp9_cost.h"

#include "vp9/encoder/vp9_bitstream.h"

#include "vp9/encoder/vp9_encodemv.h"

#include "vp9/encoder/vp9_mcomp.h"

#include "vp9/encoder/vp9_segmentation.h"

#include "vp9/encoder/vp9_subexp.h"

#include "vp9/encoder/vp9_tokenize.h"

static const struct vp9_token intra_mode_encodings[INTRA_MODES] = {

  { 0, 1 },  { 6, 3 },   { 28, 5 },  { 30, 5 }, { 58, 6 },

  { 59, 6 }, { 126, 7 }, { 127, 7 }, { 62, 6 }, { 2, 2 }

};

static const struct vp9_token

    switchable_interp_encodings[SWITCHABLE_FILTERS] = { { 0, 1 },

                                                        { 2, 2 },

                                                        { 3, 2 } };

static const struct vp9_token partition_encodings[PARTITION_TYPES] = {

  { 0, 1 }, { 2, 2 }, { 6, 3 }, { 7, 3 }

};

static const struct vp9_token inter_mode_encodings[INTER_MODES] = {

  { 2, 2 }, { 6, 3 }, { 0, 1 }, { 7, 3 }

};

static void write_intra_mode(vpx_writer *w, PREDICTION_MODE mode,

                             const vpx_prob *probs) {

  vp9_write_token(w, vp9_intra_mode_tree, probs, &intra_mode_encodings[mode]);

}

static void write_inter_mode(vpx_writer *w, PREDICTION_MODE mode,

                             const vpx_prob *probs) {

  assert(is_inter_mode(mode));

  vp9_write_token(w, vp9_inter_mode_tree, probs,

                  &inter_mode_encodings[INTER_OFFSET(mode)]);

}

static void encode_unsigned_max(struct vpx_write_bit_buffer *wb, int data,

                                int max) {

  vpx_wb_write_literal(wb, data, get_unsigned_bits(max));

}

static void prob_diff_update(const vpx_tree_index *tree,

                             vpx_prob probs[/*n - 1*/],

                             const unsigned int counts[/*n - 1*/], int n,

                             vpx_writer *w) {

  int i;

  unsigned int branch_ct[32][2];

  // Assuming max number of probabilities <= 32

  assert(n <= 32);

  vp9_tree_probs_from_distribution(tree, branch_ct, counts);

  for (i = 0; i < n - 1; ++i)

    vp9_cond_prob_diff_update(w, &probs[i], branch_ct[i]);

}

static void write_selected_tx_size(const VP9_COMMON *cm,

                                   const MACROBLOCKD *const xd, vpx_writer *w) {

  TX_SIZE tx_size = xd->mi[0]->tx_size;

  BLOCK_SIZE bsize = xd->mi[0]->sb_type;

  const TX_SIZE max_tx_size = max_txsize_lookup[bsize];

  const vpx_prob *const tx_probs =

      get_tx_probs(max_tx_size, get_tx_size_context(xd), &cm->fc->tx_probs);

  vpx_write(w, tx_size != TX_4X4, tx_probs[0]);

  if (tx_size != TX_4X4 && max_tx_size >= TX_16X16) {

    vpx_write(w, tx_size != TX_8X8, tx_probs[1]);

    if (tx_size != TX_8X8 && max_tx_size >= TX_32X32)

      vpx_write(w, tx_size != TX_16X16, tx_probs[2]);

  }

}

static int write_skip(const VP9_COMMON *cm, const MACROBLOCKD *const xd,

                      int segment_id, const MODE_INFO *mi, vpx_writer *w) {

  if (segfeature_active(&cm->seg, segment_id, SEG_LVL_SKIP)) {

    return 1;

  } else {

    const int skip = mi->skip;

    vpx_write(w, skip, vp9_get_skip_prob(cm, xd));

    return skip;

  }

}

static void update_skip_probs(VP9_COMMON *cm, vpx_writer *w,

                              FRAME_COUNTS *counts) {

  int k;

  for (k = 0; k < SKIP_CONTEXTS; ++k)

    vp9_cond_prob_diff_update(w, &cm->fc->skip_probs[k], counts->skip[k]);

}

static void update_switchable_interp_probs(VP9_COMMON *cm, vpx_writer *w,

                                           FRAME_COUNTS *counts) {

  int j;

  for (j = 0; j < SWITCHABLE_FILTER_CONTEXTS; ++j)

    prob_diff_update(vp9_switchable_interp_tree,

                     cm->fc->switchable_interp_prob[j],

                     counts->switchable_interp[j], SWITCHABLE_FILTERS, w);

}

static void pack_mb_tokens(vpx_writer *w, TOKENEXTRA **tp,

                           const TOKENEXTRA *const stop,

                           vpx_bit_depth_t bit_depth) {

  const TOKENEXTRA *p;

  const vp9_extra_bit *const extra_bits =

#if CONFIG_VP9_HIGHBITDEPTH

      (bit_depth == VPX_BITS_12)   ? vp9_extra_bits_high12

      : (bit_depth == VPX_BITS_10) ? vp9_extra_bits_high10

                                   : vp9_extra_bits;

#else

      vp9_extra_bits;

  (void)bit_depth;

#endif  // CONFIG_VP9_HIGHBITDEPTH

  for (p = *tp; p < stop && p->token != EOSB_TOKEN; ++p) {

    if (p->token == EOB_TOKEN) {

      vpx_write(w, 0, p->context_tree[0]);

      continue;

    }

    vpx_write(w, 1, p->context_tree[0]);

    while (p->token == ZERO_TOKEN) {

      vpx_write(w, 0, p->context_tree[1]);

      ++p;

      if (p == stop || p->token == EOSB_TOKEN) {

        *tp = (TOKENEXTRA *)(uintptr_t)p + (p->token == EOSB_TOKEN);

        return;

      }

    }

    {

      const int t = p->token;

      const vpx_prob *const context_tree = p->context_tree;

      assert(t != ZERO_TOKEN);

      assert(t != EOB_TOKEN);

      assert(t != EOSB_TOKEN);

      vpx_write(w, 1, context_tree[1]);

      if (t == ONE_TOKEN) {

        vpx_write(w, 0, context_tree[2]);

        vpx_write_bit(w, p->extra & 1);

      } else {  // t >= TWO_TOKEN && t < EOB_TOKEN

        const struct vp9_token *const a = &vp9_coef_encodings[t];

        int v = a->value;

        int n = a->len;

        const int e = p->extra;

        vpx_write(w, 1, context_tree[2]);

        vp9_write_tree(w, vp9_coef_con_tree,

                       vp9_pareto8_full[context_tree[PIVOT_NODE] - 1], v,

                       n - UNCONSTRAINED_NODES, 0);

        if (t >= CATEGORY1_TOKEN) {

          const vp9_extra_bit *const b = &extra_bits[t];

          const unsigned char *pb = b->prob;

          v = e >> 1;

          n = b->len;  // number of bits in v, assumed nonzero

          do {

            const int bb = (v >> --n) & 1;

            vpx_write(w, bb, *pb++);

          } while (n);

        }

        vpx_write_bit(w, e & 1);

      }

    }

  }

  *tp = (TOKENEXTRA *)(uintptr_t)p + (p->token == EOSB_TOKEN);

}

static void write_segment_id(vpx_writer *w, const struct segmentation *seg,

                             int segment_id) {

  if (seg->enabled && seg->update_map)

    vp9_write_tree(w, vp9_segment_tree, seg->tree_probs, segment_id, 3, 0);

}

// This function encodes the reference frame

static void write_ref_frames(const VP9_COMMON *cm, const MACROBLOCKD *const xd,

                             vpx_writer *w) {

  const MODE_INFO *const mi = xd->mi[0];

  const int is_compound = has_second_ref(mi);

  const int segment_id = mi->segment_id;

  // If segment level coding of this signal is disabled...

  // or the segment allows multiple reference frame options

  if (segfeature_active(&cm->seg, segment_id, SEG_LVL_REF_FRAME)) {

    assert(!is_compound);

    assert(mi->ref_frame[0] ==

           get_segdata(&cm->seg, segment_id, SEG_LVL_REF_FRAME));

  } else {

    // does the feature use compound prediction or not

    // (if not specified at the frame/segment level)

    if (cm->reference_mode == REFERENCE_MODE_SELECT) {

      vpx_write(w, is_compound, vp9_get_reference_mode_prob(cm, xd));

    } else {

      assert((!is_compound) == (cm->reference_mode == SINGLE_REFERENCE));

    }

    if (is_compound) {

      const int idx = cm->ref_frame_sign_bias[cm->comp_fixed_ref];

      vpx_write(w, mi->ref_frame[!idx] == cm->comp_var_ref[1],

                vp9_get_pred_prob_comp_ref_p(cm, xd));

    } else {

      const int bit0 = mi->ref_frame[0] != LAST_FRAME;

      vpx_write(w, bit0, vp9_get_pred_prob_single_ref_p1(cm, xd));

      if (bit0) {

        const int bit1 = mi->ref_frame[0] != GOLDEN_FRAME;

        vpx_write(w, bit1, vp9_get_pred_prob_single_ref_p2(cm, xd));

      }

    }

  }

}

static void pack_inter_mode_mvs(VP9_COMP *cpi, const MACROBLOCKD *const xd,

                                const MB_MODE_INFO_EXT *const mbmi_ext,

                                vpx_writer *w,

                                unsigned int *const max_mv_magnitude,

                                int interp_filter_selected[][SWITCHABLE]) {

  VP9_COMMON *const cm = &cpi->common;

  const nmv_context *nmvc = &cm->fc->nmvc;

  const struct segmentation *const seg = &cm->seg;

  const MODE_INFO *const mi = xd->mi[0];

  const PREDICTION_MODE mode = mi->mode;

  const int segment_id = mi->segment_id;

  const BLOCK_SIZE bsize = mi->sb_type;

  const int allow_hp = cm->allow_high_precision_mv;

  const int is_inter = is_inter_block(mi);

  const int is_compound = has_second_ref(mi);

  int skip, ref;

  if (seg->update_map) {

    if (seg->temporal_update) {

      const int pred_flag = mi->seg_id_predicted;

      vpx_prob pred_prob = vp9_get_pred_prob_seg_id(seg, xd);

      vpx_write(w, pred_flag, pred_prob);

      if (!pred_flag) write_segment_id(w, seg, segment_id);

    } else {

      write_segment_id(w, seg, segment_id);

    }

  }

  skip = write_skip(cm, xd, segment_id, mi, w);

  if (!segfeature_active(seg, segment_id, SEG_LVL_REF_FRAME))

    vpx_write(w, is_inter, vp9_get_intra_inter_prob(cm, xd));

  if (bsize >= BLOCK_8X8 && cm->tx_mode == TX_MODE_SELECT &&

      !(is_inter && skip)) {

    write_selected_tx_size(cm, xd, w);

  }

  if (!is_inter) {

    if (bsize >= BLOCK_8X8) {

      write_intra_mode(w, mode, cm->fc->y_mode_prob[size_group_lookup[bsize]]);

    } else {

      int idx, idy;

      const int num_4x4_w = num_4x4_blocks_wide_lookup[bsize];

      const int num_4x4_h = num_4x4_blocks_high_lookup[bsize];

      for (idy = 0; idy < 2; idy += num_4x4_h) {

        for (idx = 0; idx < 2; idx += num_4x4_w) {

          const PREDICTION_MODE b_mode = mi->bmi[idy * 2 + idx].as_mode;

          write_intra_mode(w, b_mode, cm->fc->y_mode_prob[0]);

        }

      }

    }

    write_intra_mode(w, mi->uv_mode, cm->fc->uv_mode_prob[mode]);

  } else {

    const int mode_ctx = mbmi_ext->mode_context[mi->ref_frame[0]];

    const vpx_prob *const inter_probs = cm->fc->inter_mode_probs[mode_ctx];

    write_ref_frames(cm, xd, w);

    // If segment skip is not enabled code the mode.

    if (!segfeature_active(seg, segment_id, SEG_LVL_SKIP)) {

      if (bsize >= BLOCK_8X8) {

        write_inter_mode(w, mode, inter_probs);

      }

    }

    if (cm->interp_filter == SWITCHABLE) {

      const int ctx = get_pred_context_switchable_interp(xd);

      vp9_write_token(w, vp9_switchable_interp_tree,

                      cm->fc->switchable_interp_prob[ctx],

                      &switchable_interp_encodings[mi->interp_filter]);

      ++interp_filter_selected[0][mi->interp_filter];

    } else {

      assert(mi->interp_filter == cm->interp_filter);

    }

    if (bsize < BLOCK_8X8) {

      const int num_4x4_w = num_4x4_blocks_wide_lookup[bsize];

      const int num_4x4_h = num_4x4_blocks_high_lookup[bsize];

      int idx, idy;

      for (idy = 0; idy < 2; idy += num_4x4_h) {

        for (idx = 0; idx < 2; idx += num_4x4_w) {

          const int j = idy * 2 + idx;

          const PREDICTION_MODE b_mode = mi->bmi[j].as_mode;

          write_inter_mode(w, b_mode, inter_probs);

          if (b_mode == NEWMV) {

            for (ref = 0; ref < 1 + is_compound; ++ref)

              vp9_encode_mv(cpi, w, &mi->bmi[j].as_mv[ref].as_mv,

                            &mbmi_ext->ref_mvs[mi->ref_frame[ref]][0].as_mv,

                            nmvc, allow_hp, max_mv_magnitude);

          }

        }

      }

    } else {

      if (mode == NEWMV) {

        for (ref = 0; ref < 1 + is_compound; ++ref)

          vp9_encode_mv(cpi, w, &mi->mv[ref].as_mv,

                        &mbmi_ext->ref_mvs[mi->ref_frame[ref]][0].as_mv, nmvc,

                        allow_hp, max_mv_magnitude);

      }

    }

  }

}

static void write_mb_modes_kf(const VP9_COMMON *cm, const MACROBLOCKD *xd,

                              vpx_writer *w) {

  const struct segmentation *const seg = &cm->seg;

  const MODE_INFO *const mi = xd->mi[0];

  const MODE_INFO *const above_mi = xd->above_mi;

  const MODE_INFO *const left_mi = xd->left_mi;

  const BLOCK_SIZE bsize = mi->sb_type;

  if (seg->update_map) write_segment_id(w, seg, mi->segment_id);

  write_skip(cm, xd, mi->segment_id, mi, w);

  if (bsize >= BLOCK_8X8 && cm->tx_mode == TX_MODE_SELECT)

    write_selected_tx_size(cm, xd, w);

  if (bsize >= BLOCK_8X8) {

    write_intra_mode(w, mi->mode, get_y_mode_probs(mi, above_mi, left_mi, 0));

  } else {

    const int num_4x4_w = num_4x4_blocks_wide_lookup[bsize];

    const int num_4x4_h = num_4x4_blocks_high_lookup[bsize];

    int idx, idy;

    for (idy = 0; idy < 2; idy += num_4x4_h) {

      for (idx = 0; idx < 2; idx += num_4x4_w) {

        const int block = idy * 2 + idx;

        write_intra_mode(w, mi->bmi[block].as_mode,

                         get_y_mode_probs(mi, above_mi, left_mi, block));

      }

    }

  }

  write_intra_mode(w, mi->uv_mode, vp9_kf_uv_mode_prob[mi->mode]);

}

static void write_modes_b(VP9_COMP *cpi, MACROBLOCKD *const xd,

                          const TileInfo *const tile, vpx_writer *w,

                          TOKENEXTRA **tok, const TOKENEXTRA *const tok_end,

                          int mi_row, int mi_col,

                          unsigned int *const max_mv_magnitude,

                          int interp_filter_selected[][SWITCHABLE]) {

  const VP9_COMMON *const cm = &cpi->common;

  const MB_MODE_INFO_EXT *const mbmi_ext =

      cpi->td.mb.mbmi_ext_base + (mi_row * cm->mi_cols + mi_col);

  MODE_INFO *m;

  xd->mi = cm->mi_grid_visible + (mi_row * cm->mi_stride + mi_col);

  m = xd->mi[0];

  set_mi_row_col(xd, tile, mi_row, num_8x8_blocks_high_lookup[m->sb_type],

                 mi_col, num_8x8_blocks_wide_lookup[m->sb_type], cm->mi_rows,

                 cm->mi_cols);

  if (frame_is_intra_only(cm)) {

    write_mb_modes_kf(cm, xd, w);

  } else {

    pack_inter_mode_mvs(cpi, xd, mbmi_ext, w, max_mv_magnitude,

                        interp_filter_selected);

  }

  assert(*tok < tok_end);

  pack_mb_tokens(w, tok, tok_end, cm->bit_depth);

}

static void write_partition(const VP9_COMMON *const cm,

                            const MACROBLOCKD *const xd, int hbs, int mi_row,

                            int mi_col, PARTITION_TYPE p, BLOCK_SIZE bsize,

                            vpx_writer *w) {

  const int ctx = partition_plane_context(xd, mi_row, mi_col, bsize);

  const vpx_prob *const probs = xd->partition_probs[ctx];

  const int has_rows = (mi_row + hbs) < cm->mi_rows;

  const int has_cols = (mi_col + hbs) < cm->mi_cols;

  if (has_rows && has_cols) {

    vp9_write_token(w, vp9_partition_tree, probs, &partition_encodings[p]);

  } else if (!has_rows && has_cols) {

    assert(p == PARTITION_SPLIT || p == PARTITION_HORZ);

    vpx_write(w, p == PARTITION_SPLIT, probs[1]);

  } else if (has_rows && !has_cols) {

    assert(p == PARTITION_SPLIT || p == PARTITION_VERT);

    vpx_write(w, p == PARTITION_SPLIT, probs[2]);

  } else {

    assert(p == PARTITION_SPLIT);

  }

}

static void write_modes_sb(VP9_COMP *cpi, MACROBLOCKD *const xd,

                           const TileInfo *const tile, vpx_writer *w,

                           TOKENEXTRA **tok, const TOKENEXTRA *const tok_end,

                           int mi_row, int mi_col, BLOCK_SIZE bsize,

                           unsigned int *const max_mv_magnitude,

                           int interp_filter_selected[][SWITCHABLE]) {

  const VP9_COMMON *const cm = &cpi->common;

  const int bsl = b_width_log2_lookup[bsize];

  const int bs = (1 << bsl) / 4;

  PARTITION_TYPE partition;

  BLOCK_SIZE subsize;

  const MODE_INFO *m = NULL;

  if (mi_row >= cm->mi_rows || mi_col >= cm->mi_cols) return;

  m = cm->mi_grid_visible[mi_row * cm->mi_stride + mi_col];

  partition = partition_lookup[bsl][m->sb_type];

  write_partition(cm, xd, bs, mi_row, mi_col, partition, bsize, w);

  subsize = get_subsize(bsize, partition);

  if (subsize < BLOCK_8X8) {

    write_modes_b(cpi, xd, tile, w, tok, tok_end, mi_row, mi_col,

                  max_mv_magnitude, interp_filter_selected);

  } else {

    switch (partition) {

      case PARTITION_NONE:

        write_modes_b(cpi, xd, tile, w, tok, tok_end, mi_row, mi_col,

                      max_mv_magnitude, interp_filter_selected);

        break;

      case PARTITION_HORZ:

        write_modes_b(cpi, xd, tile, w, tok, tok_end, mi_row, mi_col,

                      max_mv_magnitude, interp_filter_selected);

        if (mi_row + bs < cm->mi_rows)

          write_modes_b(cpi, xd, tile, w, tok, tok_end, mi_row + bs, mi_col,

                        max_mv_magnitude, interp_filter_selected);

        break;

      case PARTITION_VERT:

        write_modes_b(cpi, xd, tile, w, tok, tok_end, mi_row, mi_col,

                      max_mv_magnitude, interp_filter_selected);

        if (mi_col + bs < cm->mi_cols)

          write_modes_b(cpi, xd, tile, w, tok, tok_end, mi_row, mi_col + bs,

                        max_mv_magnitude, interp_filter_selected);

        break;

      default:

        assert(partition == PARTITION_SPLIT);

        write_modes_sb(cpi, xd, tile, w, tok, tok_end, mi_row, mi_col, subsize,

                       max_mv_magnitude, interp_filter_selected);

        write_modes_sb(cpi, xd, tile, w, tok, tok_end, mi_row, mi_col + bs,

                       subsize, max_mv_magnitude, interp_filter_selected);

        write_modes_sb(cpi, xd, tile, w, tok, tok_end, mi_row + bs, mi_col,

                       subsize, max_mv_magnitude, interp_filter_selected);

        write_modes_sb(cpi, xd, tile, w, tok, tok_end, mi_row + bs, mi_col + bs,

                       subsize, max_mv_magnitude, interp_filter_selected);

        break;

    }

  }

  // update partition context

  if (bsize >= BLOCK_8X8 &&

      (bsize == BLOCK_8X8 || partition != PARTITION_SPLIT))

    update_partition_context(xd, mi_row, mi_col, subsize, bsize);

}

static void write_modes(VP9_COMP *cpi, MACROBLOCKD *const xd,

                        const TileInfo *const tile, vpx_writer *w, int tile_row,

                        int tile_col, unsigned int *const max_mv_magnitude,

                        int interp_filter_selected[][SWITCHABLE]) {

  const VP9_COMMON *const cm = &cpi->common;

  int mi_row, mi_col, tile_sb_row;

  TOKENEXTRA *tok = NULL;

  TOKENEXTRA *tok_end = NULL;

  set_partition_probs(cm, xd);

  for (mi_row = tile->mi_row_start; mi_row < tile->mi_row_end;

       mi_row += MI_BLOCK_SIZE) {

    tile_sb_row = mi_cols_aligned_to_sb(mi_row - tile->mi_row_start) >>

                  MI_BLOCK_SIZE_LOG2;

    tok = cpi->tplist[tile_row][tile_col][tile_sb_row].start;

    tok_end = tok + cpi->tplist[tile_row][tile_col][tile_sb_row].count;

    vp9_zero(xd->left_seg_context);

    for (mi_col = tile->mi_col_start; mi_col < tile->mi_col_end;

         mi_col += MI_BLOCK_SIZE)

      write_modes_sb(cpi, xd, tile, w, &tok, tok_end, mi_row, mi_col,

                     BLOCK_64X64, max_mv_magnitude, interp_filter_selected);

    assert(tok == cpi->tplist[tile_row][tile_col][tile_sb_row].stop);

  }

}

static void build_tree_distribution(VP9_COMP *cpi, TX_SIZE tx_size,

                                    vp9_coeff_stats *coef_branch_ct,

                                    vp9_coeff_probs_model *coef_probs) {

  vp9_coeff_count *coef_counts = cpi->td.rd_counts.coef_counts[tx_size];

  unsigned int(*eob_branch_ct)[REF_TYPES][COEF_BANDS][COEFF_CONTEXTS] =

      cpi->common.counts.eob_branch[tx_size];

  int i, j, k, l, m;

  for (i = 0; i < PLANE_TYPES; ++i) {

    for (j = 0; j < REF_TYPES; ++j) {

      for (k = 0; k < COEF_BANDS; ++k) {

        for (l = 0; l < BAND_COEFF_CONTEXTS(k); ++l) {

          vp9_tree_probs_from_distribution(vp9_coef_tree,

                                           coef_branch_ct[i][j][k][l],

                                           coef_counts[i][j][k][l]);

          coef_branch_ct[i][j][k][l][0][1] =

              eob_branch_ct[i][j][k][l] - coef_branch_ct[i][j][k][l][0][0];

          for (m = 0; m < UNCONSTRAINED_NODES; ++m)

            coef_probs[i][j][k][l][m] =

                get_binary_prob(coef_branch_ct[i][j][k][l][m][0],

                                coef_branch_ct[i][j][k][l][m][1]);

        }

      }

    }

  }

}

static void update_coef_probs_common(vpx_writer *const bc, VP9_COMP *cpi,

                                     TX_SIZE tx_size,

                                     vp9_coeff_stats *frame_branch_ct,

                                     vp9_coeff_probs_model *new_coef_probs) {

  vp9_coeff_probs_model *old_coef_probs = cpi->common.fc->coef_probs[tx_size];

  const vpx_prob upd = DIFF_UPDATE_PROB;

  const int entropy_nodes_update = UNCONSTRAINED_NODES;

  int i, j, k, l, t;

  int stepsize = cpi->sf.coeff_prob_appx_step;

  switch (cpi->sf.use_fast_coef_updates) {

    case TWO_LOOP: {

      /* dry run to see if there is any update at all needed */

      int64_t savings = 0;

      int update[2] = { 0, 0 };

      for (i = 0; i < PLANE_TYPES; ++i) {

        for (j = 0; j < REF_TYPES; ++j) {

          for (k = 0; k < COEF_BANDS; ++k) {

            for (l = 0; l < BAND_COEFF_CONTEXTS(k); ++l) {

              for (t = 0; t < entropy_nodes_update; ++t) {

                vpx_prob newp = new_coef_probs[i][j][k][l][t];

                const vpx_prob oldp = old_coef_probs[i][j][k][l][t];

                int64_t s;

                int u = 0;

                if (t == PIVOT_NODE)

                  s = vp9_prob_diff_update_savings_search_model(

                      frame_branch_ct[i][j][k][l][0], oldp, &newp, upd,

                      stepsize);

                else

                  s = vp9_prob_diff_update_savings_search(

                      frame_branch_ct[i][j][k][l][t], oldp, &newp, upd);

                if (s > 0 && newp != oldp) u = 1;

                if (u)

                  savings += s - (int)(vp9_cost_zero(upd));

                else

                  savings -= (int)(vp9_cost_zero(upd));

                update[u]++;

              }

            }

          }

        }

      }

      // printf("Update %d %d, savings %d\n", update[0], update[1], savings);

      /* Is coef updated at all */

      if (update[1] == 0 || savings < 0) {

        vpx_write_bit(bc, 0);

        return;

      }

      vpx_write_bit(bc, 1);

      for (i = 0; i < PLANE_TYPES; ++i) {

        for (j = 0; j < REF_TYPES; ++j) {

          for (k = 0; k < COEF_BANDS; ++k) {

            for (l = 0; l < BAND_COEFF_CONTEXTS(k); ++l) {

              // calc probs and branch cts for this frame only

              for (t = 0; t < entropy_nodes_update; ++t) {

                vpx_prob newp = new_coef_probs[i][j][k][l][t];

                vpx_prob *oldp = old_coef_probs[i][j][k][l] + t;

                int64_t s;

                int u = 0;

                if (t == PIVOT_NODE)

                  s = vp9_prob_diff_update_savings_search_model(

                      frame_branch_ct[i][j][k][l][0], *oldp, &newp, upd,

                      stepsize);

                else

                  s = vp9_prob_diff_update_savings_search(

                      frame_branch_ct[i][j][k][l][t], *oldp, &newp, upd);

                if (s > 0 && newp != *oldp) u = 1;

                vpx_write(bc, u, upd);

                if (u) {

                  /* send/use new probability */

                  vp9_write_prob_diff_update(bc, newp, *oldp);

                  *oldp = newp;

                }

              }

            }

          }

        }

      }

      return;

    }

    default: {

      int updates = 0;

      int noupdates_before_first = 0;

      assert(cpi->sf.use_fast_coef_updates == ONE_LOOP_REDUCED);

      for (i = 0; i < PLANE_TYPES; ++i) {

        for (j = 0; j < REF_TYPES; ++j) {

          for (k = 0; k < COEF_BANDS; ++k) {

            for (l = 0; l < BAND_COEFF_CONTEXTS(k); ++l) {

              // calc probs and branch cts for this frame only

              for (t = 0; t < entropy_nodes_update; ++t) {

                vpx_prob newp = new_coef_probs[i][j][k][l][t];

                vpx_prob *oldp = old_coef_probs[i][j][k][l] + t;

                int64_t s;

                int u = 0;

                if (t == PIVOT_NODE) {

                  s = vp9_prob_diff_update_savings_search_model(

                      frame_branch_ct[i][j][k][l][0], *oldp, &newp, upd,

                      stepsize);

                } else {

                  s = vp9_prob_diff_update_savings_search(

                      frame_branch_ct[i][j][k][l][t], *oldp, &newp, upd);

                }

                if (s > 0 && newp != *oldp) u = 1;

                updates += u;

                if (u == 0 && updates == 0) {

                  noupdates_before_first++;

                  continue;

                }

                if (u == 1 && updates == 1) {

                  int v;

                  // first update

                  vpx_write_bit(bc, 1);

                  for (v = 0; v < noupdates_before_first; ++v)

                    vpx_write(bc, 0, upd);

                }

                vpx_write(bc, u, upd);

                if (u) {

                  /* send/use new probability */

                  vp9_write_prob_diff_update(bc, newp, *oldp);

                  *oldp = newp;

                }

              }

            }

          }

        }

      }

      if (updates == 0) {

        vpx_write_bit(bc, 0);  // no updates

      }

      return;

    }

  }

}

static void update_coef_probs(VP9_COMP *cpi, vpx_writer *w) {

  const TX_MODE tx_mode = cpi->common.tx_mode;

  const TX_SIZE max_tx_size = tx_mode_to_biggest_tx_size[tx_mode];

  TX_SIZE tx_size;

  for (tx_size = TX_4X4; tx_size <= max_tx_size; ++tx_size) {

    vp9_coeff_stats frame_branch_ct[PLANE_TYPES];

    vp9_coeff_probs_model frame_coef_probs[PLANE_TYPES];

    if (cpi->td.counts->tx.tx_totals[tx_size] <= 20 ||

        (tx_size >= TX_16X16 && cpi->sf.tx_size_search_method == USE_TX_8X8)) {

      vpx_write_bit(w, 0);

    } else {

      build_tree_distribution(cpi, tx_size, frame_branch_ct, frame_coef_probs);

      update_coef_probs_common(w, cpi, tx_size, frame_branch_ct,

                               frame_coef_probs);

    }

  }

}

static void encode_loopfilter(struct loopfilter *lf,

                              struct vpx_write_bit_buffer *wb) {

  int i;

  // Encode the loop filter level and type

  vpx_wb_write_literal(wb, lf->filter_level, 6);

  vpx_wb_write_literal(wb, lf->sharpness_level, 3);

  // Write out loop filter deltas applied at the MB level based on mode or

  // ref frame (if they are enabled).

  vpx_wb_write_bit(wb, lf->mode_ref_delta_enabled);

  if (lf->mode_ref_delta_enabled) {

    vpx_wb_write_bit(wb, lf->mode_ref_delta_update);

    if (lf->mode_ref_delta_update) {

      for (i = 0; i < MAX_REF_LF_DELTAS; i++) {

        const int delta = lf->ref_deltas[i];

        const int changed = delta != lf->last_ref_deltas[i];

        vpx_wb_write_bit(wb, changed);

        if (changed) {

          lf->last_ref_deltas[i] = delta;

          vpx_wb_write_literal(wb, abs(delta) & 0x3F, 6);

          vpx_wb_write_bit(wb, delta < 0);

        }

      }

      for (i = 0; i < MAX_MODE_LF_DELTAS; i++) {

        const int delta = lf->mode_deltas[i];

        const int changed = delta != lf->last_mode_deltas[i];

        vpx_wb_write_bit(wb, changed);

        if (changed) {

          lf->last_mode_deltas[i] = delta;

          vpx_wb_write_literal(wb, abs(delta) & 0x3F, 6);

          vpx_wb_write_bit(wb, delta < 0);

        }

      }

    }

  }

}

static void write_delta_q(struct vpx_write_bit_buffer *wb, int delta_q) {

  if (delta_q != 0) {

    vpx_wb_write_bit(wb, 1);

    vpx_wb_write_literal(wb, abs(delta_q), 4);

    vpx_wb_write_bit(wb, delta_q < 0);

  } else {

    vpx_wb_write_bit(wb, 0);

  }

}

static void encode_quantization(const VP9_COMMON *const cm,

                                struct vpx_write_bit_buffer *wb) {

  vpx_wb_write_literal(wb, cm->base_qindex, QINDEX_BITS);

  write_delta_q(wb, cm->y_dc_delta_q);

  write_delta_q(wb, cm->uv_dc_delta_q);

  write_delta_q(wb, cm->uv_ac_delta_q);

}

static void encode_segmentation(VP9_COMMON *cm, MACROBLOCKD *xd,

                                struct vpx_write_bit_buffer *wb) {

  int i, j;

  const struct segmentation *seg = &cm->seg;

  vpx_wb_write_bit(wb, seg->enabled);

  if (!seg->enabled) return;

  // Segmentation map

  vpx_wb_write_bit(wb, seg->update_map);

  if (seg->update_map) {

    // Select the coding strategy (temporal or spatial)

    vp9_choose_segmap_coding_method(cm, xd);

    // Write out probabilities used to decode unpredicted  macro-block segments

    for (i = 0; i < SEG_TREE_PROBS; i++) {

      const int prob = seg->tree_probs[i];

      const int update = prob != MAX_PROB;

      vpx_wb_write_bit(wb, update);

      if (update) vpx_wb_write_literal(wb, prob, 8);

    }

    // Write out the chosen coding method.

    vpx_wb_write_bit(wb, seg->temporal_update);

    if (seg->temporal_update) {

      for (i = 0; i < PREDICTION_PROBS; i++) {

        const int prob = seg->pred_probs[i];

        const int update = prob != MAX_PROB;

        vpx_wb_write_bit(wb, update);

        if (update) vpx_wb_write_literal(wb, prob, 8);

      }

    }

  }

  // Segmentation data

  vpx_wb_write_bit(wb, seg->update_data);

  if (seg->update_data) {

    vpx_wb_write_bit(wb, seg->abs_delta);

    for (i = 0; i < MAX_SEGMENTS; i++) {

      for (j = 0; j < SEG_LVL_MAX; j++) {

        const int active = segfeature_active(seg, i, j);

        vpx_wb_write_bit(wb, active);

        if (active) {

          const int data = get_segdata(seg, i, j);

          const int data_max = vp9_seg_feature_data_max(j);

          if (vp9_is_segfeature_signed(j)) {

            encode_unsigned_max(wb, abs(data), data_max);

            vpx_wb_write_bit(wb, data < 0);

          } else {

            encode_unsigned_max(wb, data, data_max);

          }

        }

      }

    }

  }

}

static void encode_txfm_probs(VP9_COMMON *cm, vpx_writer *w,

                              FRAME_COUNTS *counts) {

  // Mode

  vpx_write_literal(w, VPXMIN(cm->tx_mode, ALLOW_32X32), 2);

  if (cm->tx_mode >= ALLOW_32X32)

    vpx_write_bit(w, cm->tx_mode == TX_MODE_SELECT);

  // Probabilities

  if (cm->tx_mode == TX_MODE_SELECT) {

    int i, j;

    unsigned int ct_8x8p[TX_SIZES - 3][2];

    unsigned int ct_16x16p[TX_SIZES - 2][2];

    unsigned int ct_32x32p[TX_SIZES - 1][2];

    for (i = 0; i < TX_SIZE_CONTEXTS; i++) {

      tx_counts_to_branch_counts_8x8(counts->tx.p8x8[i], ct_8x8p);

      for (j = 0; j < TX_SIZES - 3; j++)

        vp9_cond_prob_diff_update(w, &cm->fc->tx_probs.p8x8[i][j], ct_8x8p[j]);

    }

    for (i = 0; i < TX_SIZE_CONTEXTS; i++) {

      tx_counts_to_branch_counts_16x16(counts->tx.p16x16[i], ct_16x16p);

      for (j = 0; j < TX_SIZES - 2; j++)

        vp9_cond_prob_diff_update(w, &cm->fc->tx_probs.p16x16[i][j],

                                  ct_16x16p[j]);

    }

    for (i = 0; i < TX_SIZE_CONTEXTS; i++) {

      tx_counts_to_branch_counts_32x32(counts->tx.p32x32[i], ct_32x32p);

      for (j = 0; j < TX_SIZES - 1; j++)

        vp9_cond_prob_diff_update(w, &cm->fc->tx_probs.p32x32[i][j],

                                  ct_32x32p[j]);

    }

  }

}

static void write_interp_filter(INTERP_FILTER filter,

                                struct vpx_write_bit_buffer *wb) {

  const int filter_to_literal[] = { 1, 0, 2, 3 };

  vpx_wb_write_bit(wb, filter == SWITCHABLE);

  if (filter != SWITCHABLE)

    vpx_wb_write_literal(wb, filter_to_literal[filter], 2);

}

static void fix_interp_filter(VP9_COMMON *cm, FRAME_COUNTS *counts) {

  if (cm->interp_filter == SWITCHABLE) {

    // Check to see if only one of the filters is actually used

    int count[SWITCHABLE_FILTERS];

    int i, j, c = 0;

    for (i = 0; i < SWITCHABLE_FILTERS; ++i) {

      count[i] = 0;

      for (j = 0; j < SWITCHABLE_FILTER_CONTEXTS; ++j)

        count[i] += counts->switchable_interp[j][i];

      c += (count[i] > 0);

    }

    if (c == 1) {

      // Only one filter is used. So set the filter at frame level

      for (i = 0; i < SWITCHABLE_FILTERS; ++i) {

        if (count[i]) {

          cm->interp_filter = i;

          break;

        }

      }

    }

  }

}

static void write_tile_info(const VP9_COMMON *const cm,

                            struct vpx_write_bit_buffer *wb) {

  int min_log2_tile_cols, max_log2_tile_cols, ones;

  vp9_get_tile_n_bits(cm->mi_cols, &min_log2_tile_cols, &max_log2_tile_cols);

  // columns

  ones = cm->log2_tile_cols - min_log2_tile_cols;

  while (ones--) vpx_wb_write_bit(wb, 1);

  if (cm->log2_tile_cols < max_log2_tile_cols) vpx_wb_write_bit(wb, 0);

  // rows

  vpx_wb_write_bit(wb, cm->log2_tile_rows != 0);

  if (cm->log2_tile_rows != 0) vpx_wb_write_bit(wb, cm->log2_tile_rows != 1);

}

int vp9_get_refresh_mask(VP9_COMP *cpi) {

  if (cpi->ext_ratectrl.ready &&

      (cpi->ext_ratectrl.funcs.rc_type & VPX_RC_GOP) != 0 &&

      cpi->ext_ratectrl.funcs.get_gop_decision != NULL) {

    GF_GROUP *const gf_group = &cpi->twopass.gf_group;

    const int this_gf_index = gf_group->index;

    const int update_ref_idx = gf_group->update_ref_idx[this_gf_index];

    if (update_ref_idx != INVALID_IDX) {

      return (1 << update_ref_idx);

    } else {

      return 0;

    }

  }

  if (vp9_preserve_existing_gf(cpi)) {

    // We have decided to preserve the previously existing golden frame as our

    // new ARF frame. However, in the short term we leave it in the GF slot and,

    // if we're updating the GF with the current decoded frame, we save it

    // instead to the ARF slot.

    // Later, in the function vp9_encoder.c:vp9_update_reference_frames() we

    // will swap gld_fb_idx and alt_fb_idx to achieve our objective. We do it

    // there so that it can be done outside of the recode loop.

    // Note: This is highly specific to the use of ARF as a forward reference,

    // and this needs to be generalized as other uses are implemented

    // (like RTC/temporal scalability).

    return (cpi->refresh_last_frame << cpi->lst_fb_idx) |

           (cpi->refresh_golden_frame << cpi->alt_fb_idx);

  } else {

    int arf_idx = cpi->alt_fb_idx;

    GF_GROUP *const gf_group = &cpi->twopass.gf_group;

    if (cpi->multi_layer_arf) {

      for (arf_idx = 0; arf_idx < REF_FRAMES; ++arf_idx) {

        if (arf_idx != cpi->alt_fb_idx && arf_idx != cpi->lst_fb_idx &&

            arf_idx != cpi->gld_fb_idx) {

          int idx;

          for (idx = 0; idx < gf_group->stack_size; ++idx)

            if (arf_idx == gf_group->arf_index_stack[idx]) break;

          if (idx == gf_group->stack_size) break;

        }

      }

    }

    cpi->twopass.gf_group.top_arf_idx = arf_idx;

    if (cpi->use_svc && cpi->svc.use_set_ref_frame_config &&

        cpi->svc.temporal_layering_mode == VP9E_TEMPORAL_LAYERING_MODE_BYPASS)

      return cpi->svc.update_buffer_slot[cpi->svc.spatial_layer_id];

    return (cpi->refresh_last_frame << cpi->lst_fb_idx) |

           (cpi->refresh_golden_frame << cpi->gld_fb_idx) |

           (cpi->refresh_alt_ref_frame << arf_idx);

  }

}

static int encode_tile_worker(void *arg1, void *arg2) {

  VP9_COMP *cpi = (VP9_COMP *)arg1;

  VP9BitstreamWorkerData *data = (VP9BitstreamWorkerData *)arg2;

  MACROBLOCKD *const xd = &data->xd;

  const int tile_row = 0;

  vpx_start_encode(&data->bit_writer, data->dest, data->dest_size);

  write_modes(cpi, xd, &cpi->tile_data[data->tile_idx].tile_info,

              &data->bit_writer, tile_row, data->tile_idx,

              &data->max_mv_magnitude, data->interp_filter_selected);

  return vpx_stop_encode(&data->bit_writer) == 0;

}

void vp9_bitstream_encode_tiles_buffer_dealloc(VP9_COMP *const cpi) {

  if (cpi->vp9_bitstream_worker_data) {

    int i;

    for (i = 1; i < cpi->num_workers; ++i) {

      vpx_free(cpi->vp9_bitstream_worker_data[i].dest);

    }

    vpx_free(cpi->vp9_bitstream_worker_data);

    cpi->vp9_bitstream_worker_data = NULL;

  }

}

static size_t encode_tiles_buffer_alloc_size(const VP9_COMP *cpi) {

  const VP9_COMMON *cm = &cpi->common;

  const int image_bps =