/*
 * 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 "./aom_config.h"
#include "./aom_dsp_rtcd.h"
#include "./aom_scale_rtcd.h"
#include "./av1_rtcd.h"

#include "aom/aom_codec.h"
#include "aom_dsp/aom_dsp_common.h"
#include "aom_dsp/binary_codes_reader.h"
#include "aom_dsp/bitreader.h"
#include "aom_dsp/bitreader_buffer.h"
#include "aom_mem/aom_mem.h"
#include "aom_ports/aom_timer.h"
#include "aom_ports/mem.h"
#include "aom_ports/mem_ops.h"
#include "aom_scale/aom_scale.h"
#include "aom_util/aom_thread.h"

#if CONFIG_BITSTREAM_DEBUG || CONFIG_MISMATCH_DEBUG
#include "aom_util/debug_util.h"
#endif  // CONFIG_BITSTREAM_DEBUG || CONFIG_MISMATCH_DEBUG

#include "av1/common/alloccommon.h"
#include "av1/common/cdef.h"
#include "av1/common/cfl.h"
#if CONFIG_INSPECTION
#include "av1/decoder/inspection.h"
#endif
#include "av1/common/common.h"
#include "av1/common/entropy.h"
#include "av1/common/entropymode.h"
#include "av1/common/entropymv.h"
#include "av1/common/idct.h"
#include "av1/common/mvref_common.h"
#include "av1/common/pred_common.h"
#include "av1/common/quant_common.h"
#include "av1/common/reconinter.h"
#include "av1/common/reconintra.h"
#include "av1/common/resize.h"
#include "av1/common/seg_common.h"
#include "av1/common/thread_common.h"
#include "av1/common/tile_common.h"
#include "av1/common/warped_motion.h"
#include "av1/decoder/decodeframe.h"
#include "av1/decoder/decodemv.h"
#include "av1/decoder/decoder.h"
#include "av1/decoder/decodetxb.h"
#include "av1/decoder/detokenize.h"

#define MAX_AV1_HEADER_SIZE 80
#define ACCT_STR __func__

static void loop_restoration_read_sb_coeffs(const AV1_COMMON *const cm,
                                            MACROBLOCKD *xd,
                                            aom_reader *const r, int plane,
                                            int runit_idx);

static void setup_compound_reference_mode(AV1_COMMON *cm) {
  cm->comp_fwd_ref[0] = LAST_FRAME;
  cm->comp_fwd_ref[1] = LAST2_FRAME;
  cm->comp_fwd_ref[2] = LAST3_FRAME;
  cm->comp_fwd_ref[3] = GOLDEN_FRAME;

  cm->comp_bwd_ref[0] = BWDREF_FRAME;
  cm->comp_bwd_ref[1] = ALTREF2_FRAME;
  cm->comp_bwd_ref[2] = ALTREF_FRAME;
}

static int read_is_valid(const uint8_t *start, size_t len, const uint8_t *end) {
  return len != 0 && len <= (size_t)(end - start);
}

static TX_MODE read_tx_mode(AV1_COMMON *cm, struct aom_read_bit_buffer *rb) {
  if (cm->all_lossless) return ONLY_4X4;
  return aom_rb_read_bit(rb) ? TX_MODE_SELECT : TX_MODE_LARGEST;
}

static REFERENCE_MODE read_frame_reference_mode(
    const AV1_COMMON *cm, struct aom_read_bit_buffer *rb) {
  if (av1_is_compound_reference_allowed(cm)) {
    return aom_rb_read_bit(rb) ? REFERENCE_MODE_SELECT : SINGLE_REFERENCE;
  } else {
    return SINGLE_REFERENCE;
  }
}

static void inverse_transform_block(MACROBLOCKD *xd, int plane,
                                    const TX_TYPE tx_type,
                                    const TX_SIZE tx_size, uint8_t *dst,
                                    int stride, int16_t scan_line, int eob,
                                    int reduced_tx_set) {
  struct macroblockd_plane *const pd = &xd->plane[plane];
  tran_low_t *const dqcoeff = pd->dqcoeff;
  av1_inverse_transform_block(xd, dqcoeff, plane, tx_type, tx_size, dst, stride,
                              eob, reduced_tx_set);
  memset(dqcoeff, 0, (scan_line + 1) * sizeof(dqcoeff[0]));
}

static void predict_and_reconstruct_intra_block(
    AV1_COMMON *cm, MACROBLOCKD *const xd, aom_reader *const r,
    MB_MODE_INFO *const mbmi, int plane, int row, int col, TX_SIZE tx_size) {
  PLANE_TYPE plane_type = get_plane_type(plane);
  av1_predict_intra_block_facade(cm, xd, plane, col, row, tx_size);

  if (!mbmi->skip) {
    struct macroblockd_plane *const pd = &xd->plane[plane];
#if TXCOEFF_TIMER
    struct aom_usec_timer timer;
    aom_usec_timer_start(&timer);
#endif
    int16_t max_scan_line = 0;
    int eob;
    av1_read_coeffs_txb_facade(cm, xd, r, row, col, plane, tx_size,
                               &max_scan_line, &eob);
    // tx_type will be read out in av1_read_coeffs_txb_facade
    const TX_TYPE tx_type = av1_get_tx_type(plane_type, xd, row, col, tx_size,
                                            cm->reduced_tx_set_used);

#if TXCOEFF_TIMER
    aom_usec_timer_mark(&timer);
    const int64_t elapsed_time = aom_usec_timer_elapsed(&timer);
    cm->txcoeff_timer += elapsed_time;
    ++cm->txb_count;
#endif
    if (eob) {
      uint8_t *dst =
          &pd->dst.buf[(row * pd->dst.stride + col) << tx_size_wide_log2[0]];
      inverse_transform_block(xd, plane, tx_type, tx_size, dst, pd->dst.stride,
                              max_scan_line, eob, cm->reduced_tx_set_used);
    }
  }
  if (plane == AOM_PLANE_Y && xd->cfl.store_y && is_cfl_allowed(mbmi)) {
    cfl_store_tx(xd, row, col, tx_size, mbmi->sb_type);
  }
}

static void decode_reconstruct_tx(AV1_COMMON *cm, MACROBLOCKD *const xd,
                                  aom_reader *r, MB_MODE_INFO *const mbmi,
                                  int plane, BLOCK_SIZE plane_bsize,
                                  int blk_row, int blk_col, int block,
                                  TX_SIZE tx_size, int *eob_total) {
  const struct macroblockd_plane *const pd = &xd->plane[plane];
  const TX_SIZE plane_tx_size =
      plane ? av1_get_uv_tx_size(mbmi, pd->subsampling_x, pd->subsampling_y)
            : mbmi->inter_tx_size[av1_get_txb_size_index(plane_bsize, blk_row,
                                                         blk_col)];
  // Scale to match transform block unit.
  const int max_blocks_high = max_block_high(xd, plane_bsize, plane);
  const int max_blocks_wide = max_block_wide(xd, plane_bsize, plane);

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

  if (tx_size == plane_tx_size || plane) {
    PLANE_TYPE plane_type = get_plane_type(plane);
#if TXCOEFF_TIMER
    struct aom_usec_timer timer;
    aom_usec_timer_start(&timer);
#endif
    int16_t max_scan_line = 0;
    int eob;
    av1_read_coeffs_txb_facade(cm, xd, r, blk_row, blk_col, plane, tx_size,
                               &max_scan_line, &eob);
    // tx_type will be read out in av1_read_coeffs_txb_facade
    const TX_TYPE tx_type = av1_get_tx_type(plane_type, xd, blk_row, blk_col,
                                            tx_size, cm->reduced_tx_set_used);
#if TXCOEFF_TIMER
    aom_usec_timer_mark(&timer);
    const int64_t elapsed_time = aom_usec_timer_elapsed(&timer);
    cm->txcoeff_timer += elapsed_time;
    ++cm->txb_count;
#endif

    if (plane == 0)
      update_txk_array(mbmi->txk_type, mbmi->sb_type, blk_row, blk_col, tx_size,
                       tx_type);

    uint8_t *dst =
        &pd->dst
             .buf[(blk_row * pd->dst.stride + blk_col) << tx_size_wide_log2[0]];
    inverse_transform_block(xd, plane, tx_type, tx_size, dst, pd->dst.stride,
                            max_scan_line, eob, cm->reduced_tx_set_used);
#if CONFIG_MISMATCH_DEBUG
    int pixel_c, pixel_r;
    BLOCK_SIZE bsize = txsize_to_bsize[tx_size];
    int blk_w = block_size_wide[bsize];
    int blk_h = block_size_high[bsize];
    mi_to_pixel_loc(&pixel_c, &pixel_r, mi_col, mi_row, blk_col, blk_row,
                    pd->subsampling_x, pd->subsampling_y);
    mismatch_check_block_tx(dst, pd->dst.stride, cm->frame_offset, plane,
                            pixel_c, pixel_r, blk_w, blk_h,
                            xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH);
#endif
    *eob_total += eob;
  } else {
    const TX_SIZE sub_txs = sub_tx_size_map[1][tx_size];
    assert(IMPLIES(tx_size <= TX_4X4, sub_txs == tx_size));
    assert(IMPLIES(tx_size > TX_4X4, sub_txs < tx_size));
    const int bsw = tx_size_wide_unit[sub_txs];
    const int bsh = tx_size_high_unit[sub_txs];
    const int sub_step = bsw * bsh;

    assert(bsw > 0 && bsh > 0);

    for (int row = 0; row < tx_size_high_unit[tx_size]; row += bsh) {
      for (int col = 0; col < tx_size_wide_unit[tx_size]; col += bsw) {
        const int offsetr = blk_row + row;
        const int offsetc = blk_col + col;

        if (offsetr >= max_blocks_high || offsetc >= max_blocks_wide) continue;

        decode_reconstruct_tx(cm, xd, r, mbmi, plane, plane_bsize, offsetr,
                              offsetc, block, sub_txs, eob_total);
        block += sub_step;
      }
    }
  }
}

static void set_offsets(AV1_COMMON *const cm, MACROBLOCKD *const xd,
                        BLOCK_SIZE bsize, int mi_row, int mi_col, int bw,
                        int bh, int x_mis, int y_mis) {
  const int num_planes = av1_num_planes(cm);

  const int offset = mi_row * cm->mi_stride + mi_col;
  const TileInfo *const tile = &xd->tile;

  xd->mi = cm->mi_grid_visible + offset;
  xd->mi[0] = &cm->mi[offset];
  // TODO(slavarnway): Generate sb_type based on bwl and bhl, instead of
  // passing bsize from decode_partition().
  xd->mi[0]->mbmi.sb_type = bsize;
#if CONFIG_RD_DEBUG
  xd->mi[0]->mbmi.mi_row = mi_row;
  xd->mi[0]->mbmi.mi_col = mi_col;
#endif
  xd->cfl.mi_row = mi_row;
  xd->cfl.mi_col = mi_col;

  assert(x_mis && y_mis);
  for (int x = 1; x < x_mis; ++x) xd->mi[x] = xd->mi[0];
  int idx = cm->mi_stride;
  for (int y = 1; y < y_mis; ++y) {
    memcpy(&xd->mi[idx], &xd->mi[0], x_mis * sizeof(xd->mi[0]));
    idx += cm->mi_stride;
  }

  set_plane_n4(xd, bw, bh, num_planes);
  set_skip_context(xd, mi_row, mi_col, num_planes);

  // Distance of Mb to the various image edges. These are specified to 8th pel
  // as they are always compared to values that are in 1/8th pel units
  set_mi_row_col(xd, tile, mi_row, bh, mi_col, bw,
#if CONFIG_DEPENDENT_HORZTILES
                 cm->dependent_horz_tiles,
#endif  // CONFIG_DEPENDENT_HORZTILES
                 cm->mi_rows, cm->mi_cols);

  av1_setup_dst_planes(xd->plane, bsize, get_frame_new_buffer(cm), mi_row,
                       mi_col, num_planes);
}

static void decode_mbmi_block(AV1Decoder *const pbi, MACROBLOCKD *const xd,
                              int mi_row, int mi_col, aom_reader *r,
                              PARTITION_TYPE partition, BLOCK_SIZE bsize) {
  AV1_COMMON *const cm = &pbi->common;
  const int bw = mi_size_wide[bsize];
  const int bh = mi_size_high[bsize];
  const int x_mis = AOMMIN(bw, cm->mi_cols - mi_col);
  const int y_mis = AOMMIN(bh, cm->mi_rows - mi_row);

#if CONFIG_ACCOUNTING
  aom_accounting_set_context(&pbi->accounting, mi_col, mi_row);
#endif
  set_offsets(cm, xd, bsize, mi_row, mi_col, bw, bh, x_mis, y_mis);
  xd->mi[0]->mbmi.partition = partition;
  av1_read_mode_info(pbi, xd, mi_row, mi_col, r, x_mis, y_mis);
  if (bsize >= BLOCK_8X8 && (cm->subsampling_x || cm->subsampling_y)) {
    const BLOCK_SIZE uv_subsize =
        ss_size_lookup[bsize][cm->subsampling_x][cm->subsampling_y];
    if (uv_subsize == BLOCK_INVALID)
      aom_internal_error(xd->error_info, AOM_CODEC_CORRUPT_FRAME,
                         "Invalid block size.");
  }

  int reader_corrupted_flag = aom_reader_has_error(r);
  aom_merge_corrupted_flag(&xd->corrupted, reader_corrupted_flag);
}

static void decode_token_and_recon_block(AV1Decoder *const pbi,
                                         MACROBLOCKD *const xd, int mi_row,
                                         int mi_col, aom_reader *r,
                                         BLOCK_SIZE bsize) {
  AV1_COMMON *const cm = &pbi->common;
  const int num_planes = av1_num_planes(cm);
  const int bw = mi_size_wide[bsize];
  const int bh = mi_size_high[bsize];
  const int x_mis = AOMMIN(bw, cm->mi_cols - mi_col);
  const int y_mis = AOMMIN(bh, cm->mi_rows - mi_row);

  set_offsets(cm, xd, bsize, mi_row, mi_col, bw, bh, x_mis, y_mis);
  MB_MODE_INFO *mbmi = &xd->mi[0]->mbmi;
  CFL_CTX *const cfl = &xd->cfl;
  cfl->is_chroma_reference = is_chroma_reference(
      mi_row, mi_col, bsize, cfl->subsampling_x, cfl->subsampling_y);

  if (cm->delta_q_present_flag) {
    for (int i = 0; i < MAX_SEGMENTS; i++) {
#if CONFIG_EXT_DELTA_Q
      const int current_qindex =
          av1_get_qindex(&cm->seg, i, xd->current_qindex);
#else
      const int current_qindex = xd->current_qindex;
#endif  // CONFIG_EXT_DELTA_Q
      for (int j = 0; j < num_planes; ++j) {
        const int dc_delta_q =
            j == 0 ? cm->y_dc_delta_q
                   : (j == 1 ? cm->u_dc_delta_q : cm->v_dc_delta_q);
        const int ac_delta_q =
            j == 0 ? 0 : (j == 1 ? cm->u_ac_delta_q : cm->v_ac_delta_q);
        xd->plane[j].seg_dequant_QTX[i][0] =
            av1_dc_quant_QTX(current_qindex, dc_delta_q, cm->bit_depth);
        xd->plane[j].seg_dequant_QTX[i][1] =
            av1_ac_quant_QTX(current_qindex, ac_delta_q, cm->bit_depth);
      }
    }
  }
  if (mbmi->skip) av1_reset_skip_context(xd, mi_row, mi_col, bsize, num_planes);

  if (!is_inter_block(mbmi)) {
    const struct macroblockd_plane *const y_pd = &xd->plane[0];
    const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize, y_pd);
    int row, col;
    const int max_blocks_wide = max_block_wide(xd, plane_bsize, 0);
    const int max_blocks_high = max_block_high(xd, plane_bsize, 0);

    const BLOCK_SIZE max_unit_bsize = get_plane_block_size(BLOCK_64X64, y_pd);
    int mu_blocks_wide =
        block_size_wide[max_unit_bsize] >> tx_size_wide_log2[0];
    int mu_blocks_high =
        block_size_high[max_unit_bsize] >> tx_size_high_log2[0];
    mu_blocks_wide = AOMMIN(max_blocks_wide, mu_blocks_wide);
    mu_blocks_high = AOMMIN(max_blocks_high, mu_blocks_high);

    for (row = 0; row < max_blocks_high; row += mu_blocks_high) {
      for (col = 0; col < max_blocks_wide; col += mu_blocks_wide) {
        for (int plane = 0; plane < num_planes; ++plane) {
          const struct macroblockd_plane *const pd = &xd->plane[plane];
          if (!is_chroma_reference(mi_row, mi_col, bsize, pd->subsampling_x,
                                   pd->subsampling_y))
            continue;

          const TX_SIZE tx_size = av1_get_tx_size(plane, xd);
          const int stepr = tx_size_high_unit[tx_size];
          const int stepc = tx_size_wide_unit[tx_size];

          const int unit_height = ROUND_POWER_OF_TWO(
              AOMMIN(mu_blocks_high + row, max_blocks_high), pd->subsampling_y);
          const int unit_width = ROUND_POWER_OF_TWO(
              AOMMIN(mu_blocks_wide + col, max_blocks_wide), pd->subsampling_x);

          for (int blk_row = row >> pd->subsampling_y; blk_row < unit_height;
               blk_row += stepr)
            for (int blk_col = col >> pd->subsampling_x; blk_col < unit_width;
                 blk_col += stepc)
              predict_and_reconstruct_intra_block(cm, xd, r, mbmi, plane,
                                                  blk_row, blk_col, tx_size);
        }
      }
    }
  } else {
    for (int ref = 0; ref < 1 + has_second_ref(mbmi); ++ref) {
      const MV_REFERENCE_FRAME frame = mbmi->ref_frame[ref];
      if (frame < LAST_FRAME) {
        assert(is_intrabc_block(mbmi));
        assert(frame == INTRA_FRAME);
        assert(ref == 0);
      } else {
        RefBuffer *ref_buf = &cm->frame_refs[frame - LAST_FRAME];

        xd->block_refs[ref] = ref_buf;
        if ((!av1_is_valid_scale(&ref_buf->sf)))
          aom_internal_error(xd->error_info, AOM_CODEC_UNSUP_BITSTREAM,
                             "Reference frame has invalid dimensions");
        av1_setup_pre_planes(xd, ref, ref_buf->buf, mi_row, mi_col,
                             &ref_buf->sf, num_planes);
      }
    }

    av1_build_inter_predictors_sb(cm, xd, mi_row, mi_col, NULL, bsize);
    if (mbmi->motion_mode == OBMC_CAUSAL)
      av1_build_obmc_inter_predictors_sb(cm, xd, mi_row, mi_col);

#if CONFIG_MISMATCH_DEBUG
    for (int plane = 0; plane < num_planes; ++plane) {
      const struct macroblockd_plane *pd = &xd->plane[plane];
      int pixel_c, pixel_r;
      mi_to_pixel_loc(&pixel_c, &pixel_r, mi_col, mi_row, 0, 0,
                      pd->subsampling_x, pd->subsampling_y);
      if (!is_chroma_reference(mi_row, mi_col, bsize, pd->subsampling_x,
                               pd->subsampling_y))
        continue;
      mismatch_check_block_pre(pd->dst.buf, pd->dst.stride, cm->frame_offset,
                               plane, pixel_c, pixel_r, pd->width, pd->height,
                               xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH);
    }
#endif

    // Reconstruction
    if (!mbmi->skip) {
      int eobtotal = 0;

      const struct macroblockd_plane *const y_pd = &xd->plane[0];
      const int max_blocks_wide = max_block_wide(xd, bsize, 0);
      const int max_blocks_high = max_block_high(xd, bsize, 0);
      int row, col;

      const BLOCK_SIZE max_unit_bsize = get_plane_block_size(BLOCK_64X64, y_pd);
      int mu_blocks_wide =
          block_size_wide[max_unit_bsize] >> tx_size_wide_log2[0];
      int mu_blocks_high =
          block_size_high[max_unit_bsize] >> tx_size_high_log2[0];

      mu_blocks_wide = AOMMIN(max_blocks_wide, mu_blocks_wide);
      mu_blocks_high = AOMMIN(max_blocks_high, mu_blocks_high);

      for (row = 0; row < max_blocks_high; row += mu_blocks_high) {
        for (col = 0; col < max_blocks_wide; col += mu_blocks_wide) {
          for (int plane = 0; plane < num_planes; ++plane) {
            const struct macroblockd_plane *const pd = &xd->plane[plane];
            if (!is_chroma_reference(mi_row, mi_col, bsize, pd->subsampling_x,
                                     pd->subsampling_y))
              continue;
            const BLOCK_SIZE bsizec =
                scale_chroma_bsize(bsize, pd->subsampling_x, pd->subsampling_y);
            const BLOCK_SIZE plane_bsize = get_plane_block_size(bsizec, pd);

            TX_SIZE max_tx_size = get_vartx_max_txsize(
                xd, plane_bsize, pd->subsampling_x || pd->subsampling_y);
            const int bh_var_tx = tx_size_high_unit[max_tx_size];
            const int bw_var_tx = tx_size_wide_unit[max_tx_size];
            int block = 0;
            int step =
                tx_size_wide_unit[max_tx_size] * tx_size_high_unit[max_tx_size];
            int blk_row, blk_col;
            const int unit_height = ROUND_POWER_OF_TWO(
                AOMMIN(mu_blocks_high + row, max_blocks_high),
                pd->subsampling_y);
            const int unit_width = ROUND_POWER_OF_TWO(
                AOMMIN(mu_blocks_wide + col, max_blocks_wide),
                pd->subsampling_x);

            for (blk_row = row >> pd->subsampling_y; blk_row < unit_height;
                 blk_row += bh_var_tx) {
              for (blk_col = col >> pd->subsampling_x; blk_col < unit_width;
                   blk_col += bw_var_tx) {
                decode_reconstruct_tx(cm, xd, r, mbmi, plane, plane_bsize,
                                      blk_row, blk_col, block, max_tx_size,
                                      &eobtotal);
                block += step;
              }
            }
          }
        }
      }
    }
  }
  if (mbmi->uv_mode != UV_CFL_PRED) {
    if (!cfl->is_chroma_reference && is_inter_block(mbmi) &&
        is_cfl_allowed(mbmi)) {
      cfl_store_block(xd, mbmi->sb_type, mbmi->tx_size);
    }
  }

  int reader_corrupted_flag = aom_reader_has_error(r);
  aom_merge_corrupted_flag(&xd->corrupted, reader_corrupted_flag);
}

static void read_tx_size_vartx(MACROBLOCKD *xd, MB_MODE_INFO *mbmi,
                               TX_SIZE tx_size, int depth, int blk_row,
                               int blk_col, aom_reader *r) {
  FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  int is_split = 0;
  const BLOCK_SIZE bsize = mbmi->sb_type;
  const int max_blocks_high = max_block_high(xd, bsize, 0);
  const int max_blocks_wide = max_block_wide(xd, bsize, 0);
  if (blk_row >= max_blocks_high || blk_col >= max_blocks_wide) return;
  assert(tx_size > TX_4X4);

  if (depth == MAX_VARTX_DEPTH) {
    for (int idy = 0; idy < tx_size_high_unit[tx_size]; ++idy) {
      for (int idx = 0; idx < tx_size_wide_unit[tx_size]; ++idx) {
        const int index =
            av1_get_txb_size_index(bsize, blk_row + idy, blk_col + idx);
        mbmi->inter_tx_size[index] = tx_size;
      }
    }
    mbmi->tx_size = tx_size;
    txfm_partition_update(xd->above_txfm_context + blk_col,
                          xd->left_txfm_context + blk_row, tx_size, tx_size);
    return;
  }

  const int ctx = txfm_partition_context(xd->above_txfm_context + blk_col,
                                         xd->left_txfm_context + blk_row,
                                         mbmi->sb_type, tx_size);
  is_split = aom_read_symbol(r, ec_ctx->txfm_partition_cdf[ctx], 2, ACCT_STR);

  if (is_split) {
    const TX_SIZE sub_txs = sub_tx_size_map[1][tx_size];
    const int bsw = tx_size_wide_unit[sub_txs];
    const int bsh = tx_size_high_unit[sub_txs];

    if (sub_txs == TX_4X4) {
      for (int idy = 0; idy < tx_size_high_unit[tx_size]; ++idy) {
        for (int idx = 0; idx < tx_size_wide_unit[tx_size]; ++idx) {
          const int index =
              av1_get_txb_size_index(bsize, blk_row + idy, blk_col + idx);
          mbmi->inter_tx_size[index] = sub_txs;
        }
      }
      mbmi->tx_size = sub_txs;
      txfm_partition_update(xd->above_txfm_context + blk_col,
                            xd->left_txfm_context + blk_row, sub_txs, tx_size);
      return;
    }

    assert(bsw > 0 && bsh > 0);
    for (int row = 0; row < tx_size_high_unit[tx_size]; row += bsh) {
      for (int col = 0; col < tx_size_wide_unit[tx_size]; col += bsw) {
        int offsetr = blk_row + row;
        int offsetc = blk_col + col;
        read_tx_size_vartx(xd, mbmi, sub_txs, depth + 1, offsetr, offsetc, r);
      }
    }
  } else {
    for (int idy = 0; idy < tx_size_high_unit[tx_size]; ++idy) {
      for (int idx = 0; idx < tx_size_wide_unit[tx_size]; ++idx) {
        const int index =
            av1_get_txb_size_index(bsize, blk_row + idy, blk_col + idx);
        mbmi->inter_tx_size[index] = tx_size;
      }
    }
    mbmi->tx_size = tx_size;
    txfm_partition_update(xd->above_txfm_context + blk_col,
                          xd->left_txfm_context + blk_row, tx_size, tx_size);
  }
}

static TX_SIZE read_selected_tx_size(MACROBLOCKD *xd, int is_inter,
                                     aom_reader *r) {
  // TODO(debargha): Clean up the logic here. This function should only
  // be called for intra.
  const BLOCK_SIZE bsize = xd->mi[0]->mbmi.sb_type;
  const int32_t tx_size_cat = bsize_to_tx_size_cat(bsize, is_inter);
  const int max_depths = bsize_to_max_depth(bsize, 0);
  const int ctx = get_tx_size_context(xd);
  FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
  const int depth = aom_read_symbol(r, ec_ctx->tx_size_cdf[tx_size_cat][ctx],
                                    max_depths + 1, ACCT_STR);
  assert(depth >= 0 && depth <= max_depths);
  const TX_SIZE tx_size = depth_to_tx_size(depth, bsize, 0);
  return tx_size;
}

static TX_SIZE read_tx_size(AV1_COMMON *cm, MACROBLOCKD *xd, int is_inter,
                            int allow_select_inter, aom_reader *r) {
  const TX_MODE tx_mode = cm->tx_mode;
  const BLOCK_SIZE bsize = xd->mi[0]->mbmi.sb_type;
  if (xd->lossless[xd->mi[0]->mbmi.segment_id]) return TX_4X4;

  if (block_signals_txsize(bsize)) {
    if ((!is_inter || allow_select_inter) && tx_mode == TX_MODE_SELECT) {
      const TX_SIZE coded_tx_size = read_selected_tx_size(xd, is_inter, r);
      return coded_tx_size;
    } else {
      return tx_size_from_tx_mode(bsize, tx_mode);
    }
  } else {
    assert(IMPLIES(tx_mode == ONLY_4X4, bsize == BLOCK_4X4));
    return get_max_rect_tx_size(bsize);
  }
}

static void decode_block(AV1Decoder *const pbi, MACROBLOCKD *const xd,
                         int mi_row, int mi_col, aom_reader *r,
                         PARTITION_TYPE partition, BLOCK_SIZE bsize) {
  decode_mbmi_block(pbi, xd, mi_row, mi_col, r, partition, bsize);

  if (!is_inter_block(&xd->mi[0]->mbmi)) {
    for (int plane = 0; plane < AOMMIN(2, av1_num_planes(&pbi->common));
         ++plane) {
      if (xd->mi[0]->mbmi.palette_mode_info.palette_size[plane])
        av1_decode_palette_tokens(xd, plane, r);
    }
  }

  AV1_COMMON *cm = &pbi->common;
  MB_MODE_INFO *mbmi = &xd->mi[0]->mbmi;
  int inter_block_tx = is_inter_block(mbmi) || is_intrabc_block(mbmi);
  if (cm->tx_mode == TX_MODE_SELECT && block_signals_txsize(bsize) &&
      !mbmi->skip && inter_block_tx && !xd->lossless[mbmi->segment_id]) {
    const TX_SIZE max_tx_size = get_max_rect_tx_size(bsize);
    const int bh = tx_size_high_unit[max_tx_size];
    const int bw = tx_size_wide_unit[max_tx_size];
    const int width = block_size_wide[bsize] >> tx_size_wide_log2[0];
    const int height = block_size_high[bsize] >> tx_size_wide_log2[0];

    for (int idy = 0; idy < height; idy += bh)
      for (int idx = 0; idx < width; idx += bw)
        read_tx_size_vartx(xd, mbmi, max_tx_size, 0, idy, idx, r);
  } else {
    mbmi->tx_size = read_tx_size(cm, xd, inter_block_tx, !mbmi->skip, r);
    if (inter_block_tx)
      memset(mbmi->inter_tx_size, mbmi->tx_size, sizeof(mbmi->inter_tx_size));
    set_txfm_ctxs(mbmi->tx_size, xd->n8_w, xd->n8_h,
                  mbmi->skip && is_inter_block(mbmi), xd);
  }

  decode_token_and_recon_block(pbi, xd, mi_row, mi_col, r, bsize);
}

static PARTITION_TYPE read_partition(MACROBLOCKD *xd, int mi_row, int mi_col,
                                     aom_reader *r, int has_rows, int has_cols,
                                     BLOCK_SIZE bsize) {
  const int ctx = partition_plane_context(xd, mi_row, mi_col, bsize);
  FRAME_CONTEXT *ec_ctx = xd->tile_ctx;

  if (!has_rows && !has_cols) return PARTITION_SPLIT;

  assert(ctx >= 0);
  aom_cdf_prob *partition_cdf = ec_ctx->partition_cdf[ctx];
  if (has_rows && has_cols) {
    return (PARTITION_TYPE)aom_read_symbol(
        r, partition_cdf, partition_cdf_length(bsize), ACCT_STR);
  } else if (!has_rows && has_cols) {
    assert(bsize > BLOCK_8X8);
    aom_cdf_prob cdf[2];
    partition_gather_vert_alike(cdf, partition_cdf, bsize);
    assert(cdf[1] == AOM_ICDF(CDF_PROB_TOP));
    return aom_read_cdf(r, cdf, 2, ACCT_STR) ? PARTITION_SPLIT : PARTITION_HORZ;
  } else {
    assert(has_rows && !has_cols);
    assert(bsize > BLOCK_8X8);
    aom_cdf_prob cdf[2];
    partition_gather_horz_alike(cdf, partition_cdf, bsize);
    assert(cdf[1] == AOM_ICDF(CDF_PROB_TOP));
    return aom_read_cdf(r, cdf, 2, ACCT_STR) ? PARTITION_SPLIT : PARTITION_VERT;
  }
}

// TODO(slavarnway): eliminate bsize and subsize in future commits
static void decode_partition(AV1Decoder *const pbi, MACROBLOCKD *const xd,
                             int mi_row, int mi_col, aom_reader *r,
                             BLOCK_SIZE bsize) {
  AV1_COMMON *const cm = &pbi->common;
  const int num_8x8_wh = mi_size_wide[bsize];
  const int hbs = num_8x8_wh >> 1;
  PARTITION_TYPE partition;
  BLOCK_SIZE subsize;
  const int quarter_step = num_8x8_wh / 4;
  BLOCK_SIZE bsize2 = get_subsize(bsize, PARTITION_SPLIT);
  const int has_rows = (mi_row + hbs) < cm->mi_rows;
  const int has_cols = (mi_col + hbs) < cm->mi_cols;

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

  const int num_planes = av1_num_planes(cm);
  for (int plane = 0; plane < num_planes; ++plane) {
    int rcol0, rcol1, rrow0, rrow1, tile_tl_idx;
    if (av1_loop_restoration_corners_in_sb(cm, plane, mi_row, mi_col, bsize,
                                           &rcol0, &rcol1, &rrow0, &rrow1,
                                           &tile_tl_idx)) {
      const int rstride = cm->rst_info[plane].horz_units_per_tile;
      for (int rrow = rrow0; rrow < rrow1; ++rrow) {
        for (int rcol = rcol0; rcol < rcol1; ++rcol) {
          const int runit_idx = tile_tl_idx + rcol + rrow * rstride;
          loop_restoration_read_sb_coeffs(cm, xd, r, plane, runit_idx);
        }
      }
    }
  }

  partition = (bsize < BLOCK_8X8) ? PARTITION_NONE
                                  : read_partition(xd, mi_row, mi_col, r,
                                                   has_rows, has_cols, bsize);
  subsize = subsize_lookup[partition][bsize];  // get_subsize(bsize, partition);

  // Check the bitstream is conformant: if there is subsampling on the
  // chroma planes, subsize must subsample to a valid block size.
  const struct macroblockd_plane *const pd_u = &xd->plane[1];
  if (get_plane_block_size(subsize, pd_u) == BLOCK_INVALID) {
    aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                       "Block size %dx%d invalid with this subsampling mode",
                       block_size_wide[subsize], block_size_high[subsize]);
  }

#define DEC_BLOCK_STX_ARG
#define DEC_BLOCK_EPT_ARG partition,
#define DEC_BLOCK(db_r, db_c, db_subsize)                   \
  decode_block(pbi, xd, DEC_BLOCK_STX_ARG(db_r), (db_c), r, \
               DEC_BLOCK_EPT_ARG(db_subsize))
#define DEC_PARTITION(db_r, db_c, db_subsize) \
  decode_partition(pbi, xd, DEC_BLOCK_STX_ARG(db_r), (db_c), r, (db_subsize))

  switch (partition) {
    case PARTITION_NONE: DEC_BLOCK(mi_row, mi_col, subsize); break;
    case PARTITION_HORZ:
      DEC_BLOCK(mi_row, mi_col, subsize);
      if (has_rows) DEC_BLOCK(mi_row + hbs, mi_col, subsize);
      break;
    case PARTITION_VERT:
      DEC_BLOCK(mi_row, mi_col, subsize);
      if (has_cols) DEC_BLOCK(mi_row, mi_col + hbs, subsize);
      break;
    case PARTITION_SPLIT:
      DEC_PARTITION(mi_row, mi_col, subsize);
      DEC_PARTITION(mi_row, mi_col + hbs, subsize);
      DEC_PARTITION(mi_row + hbs, mi_col, subsize);
      DEC_PARTITION(mi_row + hbs, mi_col + hbs, subsize);
      break;
    case PARTITION_HORZ_A:
      DEC_BLOCK(mi_row, mi_col, bsize2);
      DEC_BLOCK(mi_row, mi_col + hbs, bsize2);
      DEC_BLOCK(mi_row + hbs, mi_col, subsize);
      break;
    case PARTITION_HORZ_B:
      DEC_BLOCK(mi_row, mi_col, subsize);
      DEC_BLOCK(mi_row + hbs, mi_col, bsize2);
      DEC_BLOCK(mi_row + hbs, mi_col + hbs, bsize2);
      break;
    case PARTITION_VERT_A:
      DEC_BLOCK(mi_row, mi_col, bsize2);
      DEC_BLOCK(mi_row + hbs, mi_col, bsize2);
      DEC_BLOCK(mi_row, mi_col + hbs, subsize);
      break;
    case PARTITION_VERT_B:
      DEC_BLOCK(mi_row, mi_col, subsize);
      DEC_BLOCK(mi_row, mi_col + hbs, bsize2);
      DEC_BLOCK(mi_row + hbs, mi_col + hbs, bsize2);
      break;
    case PARTITION_HORZ_4:
      for (int i = 0; i < 4; ++i) {
        int this_mi_row = mi_row + i * quarter_step;
        if (i > 0 && this_mi_row >= cm->mi_rows) break;
        DEC_BLOCK(this_mi_row, mi_col, subsize);
      }
      break;
    case PARTITION_VERT_4:
      for (int i = 0; i < 4; ++i) {
        int this_mi_col = mi_col + i * quarter_step;
        if (i > 0 && this_mi_col >= cm->mi_cols) break;
        DEC_BLOCK(mi_row, this_mi_col, subsize);
      }
      break;
    default: assert(0 && "Invalid partition type");
  }

#undef DEC_PARTITION
#undef DEC_BLOCK
#undef DEC_BLOCK_EPT_ARG
#undef DEC_BLOCK_STX_ARG

  update_ext_partition_context(xd, mi_row, mi_col, subsize, bsize, partition);
}

static void setup_bool_decoder(const uint8_t *data, const uint8_t *data_end,
                               const size_t read_size,
                               struct aom_internal_error_info *error_info,
                               aom_reader *r, uint8_t allow_update_cdf) {
  // Validate the calculated partition length. If the buffer
  // described by the partition can't be fully read, then restrict
  // it to the portion that can be (for EC mode) or throw an error.
  if (!read_is_valid(data, read_size, data_end))
    aom_internal_error(error_info, AOM_CODEC_CORRUPT_FRAME,
                       "Truncated packet or corrupt tile length");

  if (aom_reader_init(r, data, read_size))
    aom_internal_error(error_info, AOM_CODEC_MEM_ERROR,
                       "Failed to allocate bool decoder %d", 1);

  r->allow_update_cdf = allow_update_cdf;
}

static void setup_segmentation(AV1_COMMON *const cm,
                               struct aom_read_bit_buffer *rb) {
  struct segmentation *const seg = &cm->seg;

  seg->update_map = 0;
  seg->update_data = 0;
  seg->temporal_update = 0;

  seg->enabled = aom_rb_read_bit(rb);
  if (!seg->enabled) {
#if CONFIG_SEGMENT_PRED_LAST
    if (cm->cur_frame->seg_map)
      memset(cm->cur_frame->seg_map, 0, (cm->mi_rows * cm->mi_cols));
#endif  // CONFIG_SEGMENT_PRED_LAST
    return;
  }
#if CONFIG_SEGMENT_PRED_LAST
  if (cm->seg.enabled && cm->prev_frame &&
      (cm->mi_rows == cm->prev_frame->mi_rows) &&
      (cm->mi_cols == cm->prev_frame->mi_cols)) {
    cm->last_frame_seg_map = cm->prev_frame->seg_map;
  } else {
    cm->last_frame_seg_map = NULL;
  }
#endif
  // Segmentation map update
  if (frame_is_intra_only(cm) || cm->error_resilient_mode) {
    seg->update_map = 1;
  } else {
    seg->update_map = aom_rb_read_bit(rb);
  }
  if (seg->update_map) {
    if (frame_is_intra_only(cm) || cm->error_resilient_mode) {
      seg->temporal_update = 0;
    } else {
      seg->temporal_update = aom_rb_read_bit(rb);
    }
  }

#if CONFIG_SPATIAL_SEGMENTATION
  seg->preskip_segid = 0;
#endif

  // Segmentation data update
  seg->update_data = aom_rb_read_bit(rb);
  if (seg->update_data) {
    av1_clearall_segfeatures(seg);

    for (int i = 0; i < MAX_SEGMENTS; i++) {
      for (int j = 0; j < SEG_LVL_MAX; j++) {
        int data = 0;
        const int feature_enabled = aom_rb_read_bit(rb);
        if (feature_enabled) {
#if CONFIG_SPATIAL_SEGMENTATION
          seg->preskip_segid |= j >= SEG_LVL_REF_FRAME;
          seg->last_active_segid = i;
#endif
          av1_enable_segfeature(seg, i, j);

          const int data_max = av1_seg_feature_data_max(j);
          const int data_min = -data_max;
          const int ubits = get_unsigned_bits(data_max);

          if (av1_is_segfeature_signed(j)) {
            data = aom_rb_read_inv_signed_literal(rb, ubits);
          } else {
            data = aom_rb_read_literal(rb, ubits);
          }

          data = clamp(data, data_min, data_max);
        }
        av1_set_segdata(seg, i, j, data);
      }
    }
  }
}

static void decode_restoration_mode(AV1_COMMON *cm,
                                    struct aom_read_bit_buffer *rb) {
  assert(!cm->all_lossless);
  const int num_planes = av1_num_planes(cm);
  if (cm->allow_intrabc && NO_FILTER_FOR_IBC) return;
  int all_none = 1, chroma_none = 1;
  for (int p = 0; p < num_planes; ++p) {
    RestorationInfo *rsi = &cm->rst_info[p];
    if (aom_rb_read_bit(rb)) {
      rsi->frame_restoration_type =
          aom_rb_read_bit(rb) ? RESTORE_SGRPROJ : RESTORE_WIENER;
    } else {
      rsi->frame_restoration_type =
          aom_rb_read_bit(rb) ? RESTORE_SWITCHABLE : RESTORE_NONE;
    }
    if (rsi->frame_restoration_type != RESTORE_NONE) {
      all_none = 0;
      chroma_none &= p == 0;
    }
  }
  if (!all_none) {
    assert(cm->seq_params.sb_size == BLOCK_64X64 ||
           cm->seq_params.sb_size == BLOCK_128X128);
    const int sb_size = cm->seq_params.sb_size == BLOCK_128X128 ? 128 : 64;

    for (int p = 0; p < num_planes; ++p)
      cm->rst_info[p].restoration_unit_size = sb_size;

    RestorationInfo *rsi = &cm->rst_info[0];

    if (sb_size == 64) {
      rsi->restoration_unit_size <<= aom_rb_read_bit(rb);
    }
    if (rsi->restoration_unit_size > 64) {
      rsi->restoration_unit_size <<= aom_rb_read_bit(rb);
    }
  } else {
    const int size = RESTORATION_UNITSIZE_MAX;
    for (int p = 0; p < num_planes; ++p)
      cm->rst_info[p].restoration_unit_size = size;
  }

  if (num_planes > 1) {
    int s = AOMMIN(cm->subsampling_x, cm->subsampling_y);
    if (s && !chroma_none) {
      cm->rst_info[1].restoration_unit_size =
          cm->rst_info[0].restoration_unit_size >> (aom_rb_read_bit(rb) * s);
    } else {
      cm->rst_info[1].restoration_unit_size =
          cm->rst_info[0].restoration_unit_size;
    }
    cm->rst_info[2].restoration_unit_size =
        cm->rst_info[1].restoration_unit_size;
  }
}

static void read_wiener_filter(int wiener_win, WienerInfo *wiener_info,
                               WienerInfo *ref_wiener_info, aom_reader *rb) {
  memset(wiener_info->vfilter, 0, sizeof(wiener_info->vfilter));
  memset(wiener_info->hfilter, 0, sizeof(wiener_info->hfilter));

  if (wiener_win == WIENER_WIN)
    wiener_info->vfilter[0] = wiener_info->vfilter[WIENER_WIN - 1] =
        aom_read_primitive_refsubexpfin(
            rb, WIENER_FILT_TAP0_MAXV - WIENER_FILT_TAP0_MINV + 1,
            WIENER_FILT_TAP0_SUBEXP_K,
            ref_wiener_info->vfilter[0] - WIENER_FILT_TAP0_MINV, ACCT_STR) +
        WIENER_FILT_TAP0_MINV;
  else
    wiener_info->vfilter[0] = wiener_info->vfilter[WIENER_WIN - 1] = 0;
  wiener_info->vfilter[1] = wiener_info->vfilter[WIENER_WIN - 2] =
      aom_read_primitive_refsubexpfin(
          rb, WIENER_FILT_TAP1_MAXV - WIENER_FILT_TAP1_MINV + 1,
          WIENER_FILT_TAP1_SUBEXP_K,
          ref_wiener_info->vfilter[1] - WIENER_FILT_TAP1_MINV, ACCT_STR) +
      WIENER_FILT_TAP1_MINV;
  wiener_info->vfilter[2] = wiener_info->vfilter[WIENER_WIN - 3] =
      aom_read_primitive_refsubexpfin(
          rb, WIENER_FILT_TAP2_MAXV - WIENER_FILT_TAP2_MINV + 1,
          WIENER_FILT_TAP2_SUBEXP_K,
          ref_wiener_info->vfilter[2] - WIENER_FILT_TAP2_MINV, ACCT_STR) +
      WIENER_FILT_TAP2_MINV;
  // The central element has an implicit +WIENER_FILT_STEP
  wiener_info->vfilter[WIENER_HALFWIN] =
      -2 * (wiener_info->vfilter[0] + wiener_info->vfilter[1] +
            wiener_info->vfilter[2]);

  if (wiener_win == WIENER_WIN)
    wiener_info->hfilter[0] = wiener_info->hfilter[WIENER_WIN - 1] =
        aom_read_primitive_refsubexpfin(
            rb, WIENER_FILT_TAP0_MAXV - WIENER_FILT_TAP0_MINV + 1,
            WIENER_FILT_TAP0_SUBEXP_K,
            ref_wiener_info->hfilter[0] - WIENER_FILT_TAP0_MINV, ACCT_STR) +
        WIENER_FILT_TAP0_MINV;
  else
    wiener_info->hfilter[0] = wiener_info->hfilter[WIENER_WIN - 1] = 0;
  wiener_info->hfilter[1] = wiener_info->hfilter[WIENER_WIN - 2] =
      aom_read_primitive_refsubexpfin(
          rb, WIENER_FILT_TAP1_MAXV - WIENER_FILT_TAP1_MINV + 1,
          WIENER_FILT_TAP1_SUBEXP_K,
          ref_wiener_info->hfilter[1] - WIENER_FILT_TAP1_MINV, ACCT_STR) +
      WIENER_FILT_TAP1_MINV;
  wiener_info->hfilter[2] = wiener_info->hfilter[WIENER_WIN - 3] =
      aom_read_primitive_refsubexpfin(
          rb, WIENER_FILT_TAP2_MAXV - WIENER_FILT_TAP2_MINV + 1,
          WIENER_FILT_TAP2_SUBEXP_K,
          ref_wiener_info->hfilter[2] - WIENER_FILT_TAP2_MINV, ACCT_STR) +
      WIENER_FILT_TAP2_MINV;
  // The central element has an implicit +WIENER_FILT_STEP
  wiener_info->hfilter[WIENER_HALFWIN] =
      -2 * (wiener_info->hfilter[0] + wiener_info->hfilter[1] +
            wiener_info->hfilter[2]);
  memcpy(ref_wiener_info, wiener_info, sizeof(*wiener_info));
}

#if CONFIG_SKIP_SGR
static void read_sgrproj_filter(SgrprojInfo *sgrproj_info,
                                SgrprojInfo *ref_sgrproj_info, aom_reader *rb) {
  sgrproj_info->ep = aom_read_literal(rb, SGRPROJ_PARAMS_BITS, ACCT_STR);
  const sgr_params_type *params = &sgr_params[sgrproj_info->ep];

  if (params->r0 == 0) {
    sgrproj_info->xqd[0] = 0;
    sgrproj_info->xqd[1] =
        aom_read_primitive_refsubexpfin(
            rb, SGRPROJ_PRJ_MAX1 - SGRPROJ_PRJ_MIN1 + 1, SGRPROJ_PRJ_SUBEXP_K,
            ref_sgrproj_info->xqd[1] - SGRPROJ_PRJ_MIN1, ACCT_STR) +
        SGRPROJ_PRJ_MIN1;
  } else if (params->r1 == 0) {
    sgrproj_info->xqd[0] =
        aom_read_primitive_refsubexpfin(
            rb, SGRPROJ_PRJ_MAX0 - SGRPROJ_PRJ_MIN0 + 1, SGRPROJ_PRJ_SUBEXP_K,
            ref_sgrproj_info->xqd[0] - SGRPROJ_PRJ_MIN0, ACCT_STR) +
        SGRPROJ_PRJ_MIN0;
    sgrproj_info->xqd[1] = clamp((1 << SGRPROJ_PRJ_BITS) - sgrproj_info->xqd[0],
                                 SGRPROJ_PRJ_MIN1, SGRPROJ_PRJ_MAX1);
  } else {
    sgrproj_info->xqd[0] =
        aom_read_primitive_refsubexpfin(
            rb, SGRPROJ_PRJ_MAX0 - SGRPROJ_PRJ_MIN0 + 1, SGRPROJ_PRJ_SUBEXP_K,
            ref_sgrproj_info->xqd[0] - SGRPROJ_PRJ_MIN0, ACCT_STR) +
        SGRPROJ_PRJ_MIN0;
    sgrproj_info->xqd[1] =
        aom_read_primitive_refsubexpfin(
            rb, SGRPROJ_PRJ_MAX1 - SGRPROJ_PRJ_MIN1 + 1, SGRPROJ_PRJ_SUBEXP_K,
            ref_sgrproj_info->xqd[1] - SGRPROJ_PRJ_MIN1, ACCT_STR) +
        SGRPROJ_PRJ_MIN1;
  }

  memcpy(ref_sgrproj_info, sgrproj_info, sizeof(*sgrproj_info));
}
#else   // CONFIG_SKIP_SGR
static void read_sgrproj_filter(SgrprojInfo *sgrproj_info,
                                SgrprojInfo *ref_sgrproj_info, aom_reader *rb) {
  sgrproj_info->ep = aom_read_literal(rb, SGRPROJ_PARAMS_BITS, ACCT_STR);
  sgrproj_info->xqd[0] =
      aom_read_primitive_refsubexpfin(
          rb, SGRPROJ_PRJ_MAX0 - SGRPROJ_PRJ_MIN0 + 1, SGRPROJ_PRJ_SUBEXP_K,
          ref_sgrproj_info->xqd[0] - SGRPROJ_PRJ_MIN0, ACCT_STR) +
      SGRPROJ_PRJ_MIN0;
  sgrproj_info->xqd[1] =
      aom_read_primitive_refsubexpfin(
          rb, SGRPROJ_PRJ_MAX1 - SGRPROJ_PRJ_MIN1 + 1, SGRPROJ_PRJ_SUBEXP_K,
          ref_sgrproj_info->xqd[1] - SGRPROJ_PRJ_MIN1, ACCT_STR) +
      SGRPROJ_PRJ_MIN1;
  memcpy(ref_sgrproj_info, sgrproj_info, sizeof(*sgrproj_info));
}
#endif  // CONFIG_SKIP_SGR

static void loop_restoration_read_sb_coeffs(const AV1_COMMON *const cm,
                                            MACROBLOCKD *xd,
                                            aom_reader *const r, int plane,
                                            int runit_idx) {
  const RestorationInfo *rsi = &cm->rst_info[plane];
  RestorationUnitInfo *rui = &rsi->unit_info[runit_idx];
  if (rsi->frame_restoration_type == RESTORE_NONE) return;

  assert(!cm->all_lossless);

  const int wiener_win = (plane > 0) ? WIENER_WIN_CHROMA : WIENER_WIN;
  WienerInfo *wiener_info = xd->wiener_info + plane;
  SgrprojInfo *sgrproj_info = xd->sgrproj_info + plane;

  if (rsi->frame_restoration_type == RESTORE_SWITCHABLE) {
    rui->restoration_type =
        aom_read_symbol(r, xd->tile_ctx->switchable_restore_cdf,
                        RESTORE_SWITCHABLE_TYPES, ACCT_STR);
    switch (rui->restoration_type) {
      case RESTORE_WIENER:
        read_wiener_filter(wiener_win, &rui->wiener_info, wiener_info, r);
        break;
      case RESTORE_SGRPROJ:
        read_sgrproj_filter(&rui->sgrproj_info, sgrproj_info, r);
        break;
      default: assert(rui->restoration_type == RESTORE_NONE); break;
    }
  } else if (rsi->frame_restoration_type == RESTORE_WIENER) {
    if (aom_read_symbol(r, xd->tile_ctx->wiener_restore_cdf, 2, ACCT_STR)) {
      rui->restoration_type = RESTORE_WIENER;
      read_wiener_filter(wiener_win, &rui->wiener_info, wiener_info, r);
    } else {
      rui->restoration_type = RESTORE_NONE;
    }
  } else if (rsi->frame_restoration_type == RESTORE_SGRPROJ) {
    if (aom_read_symbol(r, xd->tile_ctx->sgrproj_restore_cdf, 2, ACCT_STR)) {
      rui->restoration_type = RESTORE_SGRPROJ;
      read_sgrproj_filter(&rui->sgrproj_info, sgrproj_info, r);
    } else {
      rui->restoration_type = RESTORE_NONE;
    }
  }
}

static void setup_loopfilter(AV1_COMMON *cm, struct aom_read_bit_buffer *rb) {
  assert(!cm->all_lossless);
  const int num_planes = av1_num_planes(cm);
  if (cm->allow_intrabc && NO_FILTER_FOR_IBC) return;
  struct loopfilter *lf = &cm->lf;
  lf->filter_level[0] = aom_rb_read_literal(rb, 6);
  lf->filter_level[1] = aom_rb_read_literal(rb, 6);
  if (num_planes > 1) {
    if (lf->filter_level[0] || lf->filter_level[1]) {
      lf->filter_level_u = aom_rb_read_literal(rb, 6);
      lf->filter_level_v = aom_rb_read_literal(rb, 6);
    }
  }
  lf->sharpness_level = aom_rb_read_literal(rb, 3);

  // Read in loop filter deltas applied at the MB level based on mode or ref
  // frame.
  lf->mode_ref_delta_update = 0;

  lf->mode_ref_delta_enabled = aom_rb_read_bit(rb);
  if (lf->mode_ref_delta_enabled) {
    lf->mode_ref_delta_update = aom_rb_read_bit(rb);
    if (lf->mode_ref_delta_update) {
      for (int i = 0; i < TOTAL_REFS_PER_FRAME; i++)
        if (aom_rb_read_bit(rb))
          lf->ref_deltas[i] = aom_rb_read_inv_signed_literal(rb, 6);

      for (int i = 0; i < MAX_MODE_LF_DELTAS; i++)
        if (aom_rb_read_bit(rb))
          lf->mode_deltas[i] = aom_rb_read_inv_signed_literal(rb, 6);
    }
  }
}

static void setup_cdef(AV1_COMMON *cm, struct aom_read_bit_buffer *rb) {
  const int num_planes = av1_num_planes(cm);
  if (cm->allow_intrabc && NO_FILTER_FOR_IBC) return;
  cm->cdef_pri_damping = cm->cdef_sec_damping = aom_rb_read_literal(rb, 2) + 3;
  cm->cdef_bits = aom_rb_read_literal(rb, 2);
  cm->nb_cdef_strengths = 1 << cm->cdef_bits;
  for (int i = 0; i < cm->nb_cdef_strengths; i++) {
    cm->cdef_strengths[i] = aom_rb_read_literal(rb, CDEF_STRENGTH_BITS);
    cm->cdef_uv_strengths[i] =
        num_planes > 1 ? aom_rb_read_literal(rb, CDEF_STRENGTH_BITS) : 0;
  }
}

static INLINE int read_delta_q(struct aom_read_bit_buffer *rb) {
  return aom_rb_read_bit(rb) ? aom_rb_read_inv_signed_literal(rb, 6) : 0;
}

static void setup_quantization(AV1_COMMON *const cm,
                               struct aom_read_bit_buffer *rb) {
  const int num_planes = av1_num_planes(cm);
  cm->base_qindex = aom_rb_read_literal(rb, QINDEX_BITS);
  cm->y_dc_delta_q = read_delta_q(rb);
  if (num_planes > 1) {
    int diff_uv_delta = 0;
    if (cm->separate_uv_delta_q) diff_uv_delta = aom_rb_read_bit(rb);
    cm->u_dc_delta_q = read_delta_q(rb);
    cm->u_ac_delta_q = read_delta_q(rb);
    if (diff_uv_delta) {
      cm->v_dc_delta_q = read_delta_q(rb);
      cm->v_ac_delta_q = read_delta_q(rb);
    } else {
      cm->v_dc_delta_q = cm->u_dc_delta_q;
      cm->v_ac_delta_q = cm->u_ac_delta_q;
    }
  }
  cm->dequant_bit_depth = cm->bit_depth;
  cm->using_qmatrix = aom_rb_read_bit(rb);
  if (cm->using_qmatrix) {
#if CONFIG_AOM_QM_EXT
    cm->qm_y = aom_rb_read_literal(rb, QM_LEVEL_BITS);
    cm->qm_u = aom_rb_read_literal(rb, QM_LEVEL_BITS);
    if (!cm->separate_uv_delta_q)
      cm->qm_v = cm->qm_u;
    else
      cm->qm_v = aom_rb_read_literal(rb, QM_LEVEL_BITS);
#else
    cm->min_qmlevel = aom_rb_read_literal(rb, QM_LEVEL_BITS);
    cm->max_qmlevel = aom_rb_read_literal(rb, QM_LEVEL_BITS);
#endif
  } else {
#if CONFIG_AOM_QM_EXT
    cm->qm_y = 0;
    cm->qm_u = 0;
    cm->qm_v = 0;
#else
    cm->min_qmlevel = 0;
    cm->max_qmlevel = 0;
#endif
  }
}

// Build y/uv dequant values based on segmentation.
static void setup_segmentation_dequant(AV1_COMMON *const cm) {
  const int using_qm = cm->using_qmatrix;
#if !CONFIG_AOM_QM_EXT
  const int minqm = cm->min_qmlevel;
  const int maxqm = cm->max_qmlevel;
#endif  // !CONFIG_AOM_QM_EXT
  // When segmentation is disabled, only the first value is used.  The
  // remaining are don't cares.
  const int max_segments = cm->seg.enabled ? MAX_SEGMENTS : 1;
  for (int i = 0; i < max_segments; ++i) {
    const int qindex = av1_get_qindex(&cm->seg, i, cm->base_qindex);
    cm->y_dequant_QTX[i][0] =
        av1_dc_quant_QTX(qindex, cm->y_dc_delta_q, cm->bit_depth);
    cm->y_dequant_QTX[i][1] = av1_ac_quant_QTX(qindex, 0, cm->bit_depth);
    cm->u_dequant_QTX[i][0] =
        av1_dc_quant_QTX(qindex, cm->u_dc_delta_q, cm->bit_depth);
    cm->u_dequant_QTX[i][1] =
        av1_ac_quant_QTX(qindex, cm->u_ac_delta_q, cm->bit_depth);
    cm->v_dequant_QTX[i][0] =
        av1_dc_quant_QTX(qindex, cm->v_dc_delta_q, cm->bit_depth);
    cm->v_dequant_QTX[i][1] =
        av1_ac_quant_QTX(qindex, cm->v_ac_delta_q, cm->bit_depth);
    const int lossless = qindex == 0 && cm->y_dc_delta_q == 0 &&
                         cm->u_dc_delta_q == 0 && cm->u_ac_delta_q == 0 &&
                         cm->v_dc_delta_q == 0 && cm->v_ac_delta_q == 0;
// NB: depends on base index so there is only 1 set per frame
// No quant weighting when lossless or signalled not using QM
#if CONFIG_AOM_QM_EXT
    int qmlevel = (lossless || using_qm == 0) ? NUM_QM_LEVELS - 1 : cm->qm_y;
#else
    const int qmlevel = (lossless || using_qm == 0)
                            ? NUM_QM_LEVELS - 1
                            : aom_get_qmlevel(cm->base_qindex, minqm, maxqm);
#endif
    for (int j = 0; j < TX_SIZES_ALL; ++j) {
      cm->y_iqmatrix[i][j] = av1_iqmatrix(cm, qmlevel, AOM_PLANE_Y, j);
    }
#if CONFIG_AOM_QM_EXT
    qmlevel = (lossless || using_qm == 0) ? NUM_QM_LEVELS - 1 : cm->qm_u;
#endif
    for (int j = 0; j < TX_SIZES_ALL; ++j) {
      cm->u_iqmatrix[i][j] = av1_iqmatrix(cm, qmlevel, AOM_PLANE_U, j);
    }
#if CONFIG_AOM_QM_EXT
    qmlevel = (lossless || using_qm == 0) ? NUM_QM_LEVELS - 1 : cm->qm_v;
#endif
    for (int j = 0; j < TX_SIZES_ALL; ++j) {
      cm->v_iqmatrix[i][j] = av1_iqmatrix(cm, qmlevel, AOM_PLANE_V, j);
    }
  }
}

static InterpFilter read_frame_interp_filter(struct aom_read_bit_buffer *rb) {
  return aom_rb_read_bit(rb) ? SWITCHABLE
                             : aom_rb_read_literal(rb, LOG_SWITCHABLE_FILTERS);
}

static void setup_render_size(AV1_COMMON *cm, struct aom_read_bit_buffer *rb) {
  cm->render_width = cm->superres_upscaled_width;
  cm->render_height = cm->superres_upscaled_height;
  if (aom_rb_read_bit(rb))
    av1_read_frame_size(rb, 16, 16, &cm->render_width, &cm->render_height);
}

// TODO(afergs): make "struct aom_read_bit_buffer *const rb"?
static void setup_superres(AV1_COMMON *const cm, struct aom_read_bit_buffer *rb,
                           int *width, int *height) {
  cm->superres_upscaled_width = *width;
  cm->superres_upscaled_height = *height;
  if (aom_rb_read_bit(rb)) {
    cm->superres_scale_denominator =
        (uint8_t)aom_rb_read_literal(rb, SUPERRES_SCALE_BITS);
    cm->superres_scale_denominator += SUPERRES_SCALE_DENOMINATOR_MIN;
    // Don't edit cm->width or cm->height directly, or the buffers won't get
    // resized correctly
    av1_calculate_scaled_superres_size(width, height,
                                       cm->superres_scale_denominator);
  } else {
    // 1:1 scaling - ie. no scaling, scale not provided
    cm->superres_scale_denominator = SCALE_NUMERATOR;
  }
}

static void resize_context_buffers(AV1_COMMON *cm, int width, int height) {
#if CONFIG_SIZE_LIMIT
  if (width > DECODE_WIDTH_LIMIT || height > DECODE_HEIGHT_LIMIT)
    aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                       "Dimensions of %dx%d beyond allowed size of %dx%d.",
                       width, height, DECODE_WIDTH_LIMIT, DECODE_HEIGHT_LIMIT);
#endif
  if (cm->width != width || cm->height != height) {
    const int new_mi_rows =
        ALIGN_POWER_OF_TWO(height, MI_SIZE_LOG2) >> MI_SIZE_LOG2;
    const int new_mi_cols =
        ALIGN_POWER_OF_TWO(width, MI_SIZE_LOG2) >> MI_SIZE_LOG2;

    // Allocations in av1_alloc_context_buffers() depend on individual
    // dimensions as well as the overall size.
    if (new_mi_cols > cm->mi_cols || new_mi_rows > cm->mi_rows) {
      if (av1_alloc_context_buffers(cm, width, height))
        aom_internal_error(&cm->error, AOM_CODEC_MEM_ERROR,
                           "Failed to allocate context buffers");
    } else {
      av1_set_mb_mi(cm, width, height);
    }
    av1_init_context_buffers(cm);
    cm->width = width;
    cm->height = height;
  }

  ensure_mv_buffer(cm->cur_frame, cm);
  cm->cur_frame->width = cm->width;
  cm->cur_frame->height = cm->height;
}

static void setup_frame_size(AV1_COMMON *cm, int frame_size_override_flag,
                             struct aom_read_bit_buffer *rb) {
  int width, height;
  BufferPool *const pool = cm->buffer_pool;

  if (frame_size_override_flag) {
    int num_bits_width = cm->seq_params.num_bits_width;
    int num_bits_height = cm->seq_params.num_bits_height;
    av1_read_frame_size(rb, num_bits_width, num_bits_height, &width, &height);
    if (width > cm->seq_params.max_frame_width ||
        height > cm->seq_params.max_frame_height) {
      aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                         "Frame dimensions are larger than the maximum values");
    }
  } else {
    width = cm->seq_params.max_frame_width;
    height = cm->seq_params.max_frame_height;
  }

  setup_superres(cm, rb, &width, &height);
  resize_context_buffers(cm, width, height);
  setup_render_size(cm, rb);

  lock_buffer_pool(pool);
  if (aom_realloc_frame_buffer(
          get_frame_new_buffer(cm), cm->width, cm->height, cm->subsampling_x,
          cm->subsampling_y, cm->use_highbitdepth, AOM_BORDER_IN_PIXELS,
          cm->byte_alignment,
          &pool->frame_bufs[cm->new_fb_idx].raw_frame_buffer, pool->get_fb_cb,
          pool->cb_priv)) {
    unlock_buffer_pool(pool);
    aom_internal_error(&cm->error, AOM_CODEC_MEM_ERROR,
                       "Failed to allocate frame buffer");
  }
  unlock_buffer_pool(pool);

  pool->frame_bufs[cm->new_fb_idx].buf.subsampling_x = cm->subsampling_x;
  pool->frame_bufs[cm->new_fb_idx].buf.subsampling_y = cm->subsampling_y;
  pool->frame_bufs[cm->new_fb_idx].buf.bit_depth = (unsigned int)cm->bit_depth;
  pool->frame_bufs[cm->new_fb_idx].buf.color_primaries = cm->color_primaries;
  pool->frame_bufs[cm->new_fb_idx].buf.transfer_characteristics =
      cm->transfer_characteristics;
  pool->frame_bufs[cm->new_fb_idx].buf.matrix_coefficients =
      cm->matrix_coefficients;
  pool->frame_bufs[cm->new_fb_idx].buf.monochrome = cm->seq_params.monochrome;
  pool->frame_bufs[cm->new_fb_idx].buf.chroma_sample_position =
      cm->chroma_sample_position;
  pool->frame_bufs[cm->new_fb_idx].buf.color_range = cm->color_range;
  pool->frame_bufs[cm->new_fb_idx].buf.render_width = cm->render_width;
  pool->frame_bufs[cm->new_fb_idx].buf.render_height = cm->render_height;
}

static void setup_sb_size(SequenceHeader *seq_params,
                          struct aom_read_bit_buffer *rb) {
  (void)rb;
  set_sb_size(seq_params, aom_rb_read_bit(rb) ? BLOCK_128X128 : BLOCK_64X64);
}

static INLINE int valid_ref_frame_img_fmt(aom_bit_depth_t ref_bit_depth,
                                          int ref_xss, int ref_yss,
                                          aom_bit_depth_t this_bit_depth,
                                          int this_xss, int this_yss) {
  return ref_bit_depth == this_bit_depth && ref_xss == this_xss &&
         ref_yss == this_yss;
}

static void setup_frame_size_with_refs(AV1_COMMON *cm,
                                       struct aom_read_bit_buffer *rb) {
  int width, height;
  int found = 0;
  int has_valid_ref_frame = 0;
  BufferPool *const pool = cm->buffer_pool;
  for (int i = 0; i < INTER_REFS_PER_FRAME; ++i) {
    if (aom_rb_read_bit(rb)) {
      YV12_BUFFER_CONFIG *const buf = cm->frame_refs[i].buf;
      width = buf->y_crop_width;
      height = buf->y_crop_height;
      cm->render_width = buf->render_width;
      cm->render_height = buf->render_height;
      setup_superres(cm, rb, &width, &height);
      resize_context_buffers(cm, width, height);
      found = 1;
      break;
    }
  }

  if (!found) {
    int num_bits_width = cm->seq_params.num_bits_width;
    int num_bits_height = cm->seq_params.num_bits_height;

    av1_read_frame_size(rb, num_bits_width, num_bits_height, &width, &height);
    setup_superres(cm, rb, &width, &height);
    resize_context_buffers(cm, width, height);
    setup_render_size(cm, rb);
  }

  if (width <= 0 || height <= 0)
    aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                       "Invalid frame size");

  // Check to make sure at least one of frames that this frame references
  // has valid dimensions.
  for (int i = 0; i < INTER_REFS_PER_FRAME; ++i) {
    RefBuffer *const ref_frame = &cm->frame_refs[i];
    has_valid_ref_frame |=
        valid_ref_frame_size(ref_frame->buf->y_crop_width,
                             ref_frame->buf->y_crop_height, width, height);
  }
  if (!has_valid_ref_frame)
    aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                       "Referenced frame has invalid size");
  for (int i = 0; i < INTER_REFS_PER_FRAME; ++i) {
    RefBuffer *const ref_frame = &cm->frame_refs[i];
    if (!valid_ref_frame_img_fmt(ref_frame->buf->bit_depth,
                                 ref_frame->buf->subsampling_x,
                                 ref_frame->buf->subsampling_y, cm->bit_depth,
                                 cm->subsampling_x, cm->subsampling_y))
      aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                         "Referenced frame has incompatible color format");
  }

  lock_buffer_pool(pool);
  if (aom_realloc_frame_buffer(
          get_frame_new_buffer(cm), cm->width, cm->height, cm->subsampling_x,
          cm->subsampling_y, cm->use_highbitdepth, AOM_BORDER_IN_PIXELS,
          cm->byte_alignment,
          &pool->frame_bufs[cm->new_fb_idx].raw_frame_buffer, pool->get_fb_cb,
          pool->cb_priv)) {
    unlock_buffer_pool(pool);
    aom_internal_error(&cm->error, AOM_CODEC_MEM_ERROR,
                       "Failed to allocate frame buffer");
  }
  unlock_buffer_pool(pool);

  pool->frame_bufs[cm->new_fb_idx].buf.subsampling_x = cm->subsampling_x;
  pool->frame_bufs[cm->new_fb_idx].buf.subsampling_y = cm->subsampling_y;
  pool->frame_bufs[cm->new_fb_idx].buf.bit_depth = (unsigned int)cm->bit_depth;
  pool->frame_bufs[cm->new_fb_idx].buf.color_primaries = cm->color_primaries;
  pool->frame_bufs[cm->new_fb_idx].buf.transfer_characteristics =
      cm->transfer_characteristics;
  pool->frame_bufs[cm->new_fb_idx].buf.matrix_coefficients =
      cm->matrix_coefficients;
  pool->frame_bufs[cm->new_fb_idx].buf.monochrome = cm->seq_params.monochrome;
  pool->frame_bufs[cm->new_fb_idx].buf.chroma_sample_position =
      cm->chroma_sample_position;
  pool->frame_bufs[cm->new_fb_idx].buf.color_range = cm->color_range;
  pool->frame_bufs[cm->new_fb_idx].buf.render_width = cm->render_width;
  pool->frame_bufs[cm->new_fb_idx].buf.render_height = cm->render_height;
}

#if CONFIG_MAX_TILE

// Same function as av1_read_uniform but reading from uncompresses header wb
static int rb_read_uniform(struct aom_read_bit_buffer *const rb, int n) {
  const int l = get_unsigned_bits(n);
  const int m = (1 << l) - n;
  const int v = aom_rb_read_literal(rb, l - 1);
  assert(l != 0);
  if (v < m)
    return v;
  else
    return (v << 1) - m + aom_rb_read_literal(rb, 1);
}

static void read_tile_info_max_tile(AV1_COMMON *const cm,
                                    struct aom_read_bit_buffer *const rb) {
  int width_mi = ALIGN_POWER_OF_TWO(cm->mi_cols, cm->seq_params.mib_size_log2);
  int height_mi = ALIGN_POWER_OF_TWO(cm->mi_rows, cm->seq_params.mib_size_log2);
  int width_sb = width_mi >> cm->seq_params.mib_size_log2;
  int height_sb = height_mi >> cm->seq_params.mib_size_log2;

  av1_get_tile_limits(cm);
  cm->uniform_tile_spacing_flag = aom_rb_read_bit(rb);

  // Read tile columns
  if (cm->uniform_tile_spacing_flag) {
    cm->log2_tile_cols = cm->min_log2_tile_cols;
    while (cm->log2_tile_cols < cm->max_log2_tile_cols) {
      if (!aom_rb_read_bit(rb)) {
        break;
      }
      cm->log2_tile_cols++;
    }
  } else {
    int i;
    int start_sb;
    for (i = 0, start_sb = 0; width_sb > 0 && i < MAX_TILE_COLS; i++) {
      const int size_sb =
          1 + rb_read_uniform(rb, AOMMIN(width_sb, cm->max_tile_width_sb));
      cm->tile_col_start_sb[i] = start_sb;
      start_sb += size_sb;
      width_sb -= size_sb;
    }
    cm->tile_cols = i;
    cm->tile_col_start_sb[i] = start_sb + width_sb;
  }
  av1_calculate_tile_cols(cm);

  // Read tile rows
  if (cm->uniform_tile_spacing_flag) {
    cm->log2_tile_rows = cm->min_log2_tile_rows;
    while (cm->log2_tile_rows < cm->max_log2_tile_rows) {
      if (!aom_rb_read_bit(rb)) {
        break;
      }
      cm->log2_tile_rows++;
    }
  } else {
    int i;
    int start_sb;
    for (i = 0, start_sb = 0; height_sb > 0 && i < MAX_TILE_ROWS; i++) {
      const int size_sb =
          1 + rb_read_uniform(rb, AOMMIN(height_sb, cm->max_tile_height_sb));
      cm->tile_row_start_sb[i] = start_sb;
      start_sb += size_sb;
      height_sb -= size_sb;
    }
    cm->tile_rows = i;
    cm->tile_row_start_sb[i] = start_sb + height_sb;
  }
  av1_calculate_tile_rows(cm);
}
#endif

static void read_tile_info(AV1Decoder *const pbi,
                           struct aom_read_bit_buffer *const rb) {
  AV1_COMMON *const cm = &pbi->common;
  cm->single_tile_decoding = 0;
  if (cm->large_scale_tile) {
    struct loopfilter *lf = &cm->lf;

    // Figure out single_tile_decoding by loopfilter_level.
    const int no_loopfilter = !(lf->filter_level[0] || lf->filter_level[1]);
    const int no_cdef = cm->cdef_bits == 0 && cm->cdef_strengths[0] == 0 &&
                        cm->cdef_uv_strengths[0] == 0;
    const int no_restoration =
        cm->rst_info[0].frame_restoration_type == RESTORE_NONE &&
        cm->rst_info[1].frame_restoration_type == RESTORE_NONE &&
        cm->rst_info[2].frame_restoration_type == RESTORE_NONE;
    assert(
        IMPLIES(cm->all_lossless, no_loopfilter && no_cdef && no_restoration));
    cm->single_tile_decoding = no_loopfilter && no_cdef && no_restoration;
    // Read the tile width/height
    if (cm->seq_params.sb_size == BLOCK_128X128) {
      cm->tile_width = aom_rb_read_literal(rb, 5) + 1;
      cm->tile_height = aom_rb_read_literal(rb, 5) + 1;
    } else {
      cm->tile_width = aom_rb_read_literal(rb, 6) + 1;
      cm->tile_height = aom_rb_read_literal(rb, 6) + 1;
    }

    cm->tile_width <<= cm->seq_params.mib_size_log2;
    cm->tile_height <<= cm->seq_params.mib_size_log2;

    cm->tile_width = AOMMIN(cm->tile_width, cm->mi_cols);
    cm->tile_height = AOMMIN(cm->tile_height, cm->mi_rows);

    // Get the number of tiles
    cm->tile_cols = 1;
    while (cm->tile_cols * cm->tile_width < cm->mi_cols) ++cm->tile_cols;

    cm->tile_rows = 1;
    while (cm->tile_rows * cm->tile_height < cm->mi_rows) ++cm->tile_rows;

#if CONFIG_DEPENDENT_HORZTILES
    cm->dependent_horz_tiles = 0;
#endif
#if CONFIG_LOOPFILTERING_ACROSS_TILES
#if CONFIG_LOOPFILTERING_ACROSS_TILES_EXT
    if (cm->tile_cols > 1) {
      cm->loop_filter_across_tiles_v_enabled = aom_rb_read_bit(rb);
    } else {
      cm->loop_filter_across_tiles_v_enabled = 1;
    }
    if (cm->tile_rows > 1) {
      cm->loop_filter_across_tiles_h_enabled = aom_rb_read_bit(rb);
    } else {
      cm->loop_filter_across_tiles_h_enabled = 1;
    }
#else
    if (cm->tile_cols * cm->tile_rows > 1)
      cm->loop_filter_across_tiles_enabled = aom_rb_read_bit(rb);
    else
      cm->loop_filter_across_tiles_enabled = 1;
#endif  // CONFIG_LOOPFILTERING_ACROSS_TILES_EXT
#endif  // CONFIG_LOOPFILTERING_ACROSS_TILES

    if (cm->tile_cols * cm->tile_rows > 1) {
      // Read the number of bytes used to store tile size
      pbi->tile_col_size_bytes = aom_rb_read_literal(rb, 2) + 1;
      pbi->tile_size_bytes = aom_rb_read_literal(rb, 2) + 1;
    }
#if CONFIG_MAX_TILE
    for (int i = 0; i <= cm->tile_cols; i++) {
      cm->tile_col_start_sb[i] =
          ((i * cm->tile_width - 1) >> cm->seq_params.mib_size_log2) + 1;
    }
    for (int i = 0; i <= cm->tile_rows; i++) {
      cm->tile_row_start_sb[i] =
          ((i * cm->tile_height - 1) >> cm->seq_params.mib_size_log2) + 1;
    }
#endif  // CONFIG_MAX_TILE
    return;
  }

#if CONFIG_MAX_TILE
  read_tile_info_max_tile(cm, rb);
#else
  int min_log2_tile_cols, max_log2_tile_cols, max_ones;
  av1_get_tile_n_bits(cm->mi_cols, &min_log2_tile_cols, &max_log2_tile_cols);

  // columns
  max_ones = max_log2_tile_cols - min_log2_tile_cols;
  cm->log2_tile_cols = min_log2_tile_cols;
  while (max_ones-- && aom_rb_read_bit(rb)) cm->log2_tile_cols++;

  if (cm->log2_tile_cols > 6)
    aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                       "Invalid number of tile columns");

  // rows
  cm->log2_tile_rows = aom_rb_read_bit(rb);
  if (cm->log2_tile_rows) cm->log2_tile_rows += aom_rb_read_bit(rb);

  cm->tile_width =
      get_tile_size(cm->mi_cols, cm->log2_tile_cols, &cm->tile_cols);
  cm->tile_height =
      get_tile_size(cm->mi_rows, cm->log2_tile_rows, &cm->tile_rows);

#endif  // CONFIG_MAX_TILE
#if CONFIG_DEPENDENT_HORZTILES
  if (cm->tile_rows > 1)
    cm->dependent_horz_tiles = aom_rb_read_bit(rb);
  else
    cm->dependent_horz_tiles = 0;
#endif
#if CONFIG_LOOPFILTERING_ACROSS_TILES
#if CONFIG_LOOPFILTERING_ACROSS_TILES_EXT
  if (cm->tile_cols > 1) {
    cm->loop_filter_across_tiles_v_enabled = aom_rb_read_bit(rb);
  } else {
    cm->loop_filter_across_tiles_v_enabled = 1;
  }
  if (cm->tile_rows > 1) {
    cm->loop_filter_across_tiles_h_enabled = aom_rb_read_bit(rb);
  } else {
    cm->loop_filter_across_tiles_h_enabled = 1;
  }
#else
  if (cm->tile_cols * cm->tile_rows > 1)
    cm->loop_filter_across_tiles_enabled = aom_rb_read_bit(rb);
  else
    cm->loop_filter_across_tiles_enabled = 1;
#endif  // CONFIG_LOOPFILTERING_ACROSS_TILES_EXT
#endif  // CONFIG_LOOPFILTERING_ACROSS_TILES

  if (cm->tile_rows * cm->tile_cols > 1) {
    // tile size magnitude
    pbi->tile_size_bytes = aom_rb_read_literal(rb, 2) + 1;
  }
}

static int mem_get_varsize(const uint8_t *src, int sz) {
  switch (sz) {
    case 1: return src[0];
    case 2: return mem_get_le16(src);
    case 3: return mem_get_le24(src);
    case 4: return mem_get_le32(src);
    default: assert(0 && "Invalid size"); return -1;
  }
}

// Reads the next tile returning its size and adjusting '*data' accordingly
// based on 'is_last'.
static void get_ls_tile_buffer(
    const uint8_t *const data_end, struct aom_internal_error_info *error_info,
    const uint8_t **data, TileBufferDec (*const tile_buffers)[MAX_TILE_COLS],
    int tile_size_bytes, int col, int row, int tile_copy_mode) {
  size_t size;

  size_t copy_size = 0;
  const uint8_t *copy_data = NULL;

  if (!read_is_valid(*data, tile_size_bytes, data_end))
    aom_internal_error(error_info, AOM_CODEC_CORRUPT_FRAME,
                       "Truncated packet or corrupt tile length");
  size = mem_get_varsize(*data, tile_size_bytes);

  // If tile_copy_mode = 1, then the top bit of the tile header indicates copy
  // mode.
  if (tile_copy_mode && (size >> (tile_size_bytes * 8 - 1)) == 1) {
    // The remaining bits in the top byte signal the row offset
    int offset = (size >> (tile_size_bytes - 1) * 8) & 0x7f;

    // Currently, only use tiles in same column as reference tiles.
    copy_data = tile_buffers[row - offset][col].data;
    copy_size = tile_buffers[row - offset][col].size;
    size = 0;
  }

  *data += tile_size_bytes;

  if (size > (size_t)(data_end - *data))
    aom_internal_error(error_info, AOM_CODEC_CORRUPT_FRAME,
                       "Truncated packet or corrupt tile size");

  if (size > 0) {
    tile_buffers[row][col].data = *data;
    tile_buffers[row][col].size = size;
  } else {
    tile_buffers[row][col].data = copy_data;
    tile_buffers[row][col].size = copy_size;
  }

  *data += size;

  tile_buffers[row][col].raw_data_end = *data;
}

static void get_ls_tile_buffers(
    AV1Decoder *pbi, const uint8_t *data, const uint8_t *data_end,
    TileBufferDec (*const tile_buffers)[MAX_TILE_COLS]) {
  AV1_COMMON *const cm = &pbi->common;
  const int tile_cols = cm->tile_cols;
  const int tile_rows = cm->tile_rows;
  const int have_tiles = tile_cols * tile_rows > 1;

  if (!have_tiles) {
    const size_t tile_size = data_end - data;
    tile_buffers[0][0].data = data;
    tile_buffers[0][0].size = tile_size;
    tile_buffers[0][0].raw_data_end = NULL;
  } else {
    // We locate only the tile buffers that are required, which are the ones
    // specified by pbi->dec_tile_col and pbi->dec_tile_row. Also, we always
    // need the last (bottom right) tile buffer, as we need to know where the
    // end of the compressed frame buffer is for proper superframe decoding.

    const uint8_t *tile_col_data_end[MAX_TILE_COLS] = { NULL };
    const uint8_t *const data_start = data;

    const int dec_tile_row = AOMMIN(pbi->dec_tile_row, tile_rows);
    const int single_row = pbi->dec_tile_row >= 0;
    const int tile_rows_start = single_row ? dec_tile_row : 0;
    const int tile_rows_end = single_row ? tile_rows_start + 1 : tile_rows;
    const int dec_tile_col = AOMMIN(pbi->dec_tile_col, tile_cols);
    const int single_col = pbi->dec_tile_col >= 0;
    const int tile_cols_start = single_col ? dec_tile_col : 0;
    const int tile_cols_end = single_col ? tile_cols_start + 1 : tile_cols;

    const int tile_col_size_bytes = pbi->tile_col_size_bytes;
    const int tile_size_bytes = pbi->tile_size_bytes;
    const int tile_copy_mode =
        ((AOMMAX(cm->tile_width, cm->tile_height) << MI_SIZE_LOG2) <= 256) ? 1
                                                                           : 0;
    // Read tile column sizes for all columns (we need the last tile buffer)
    for (int c = 0; c < tile_cols; ++c) {
      const int is_last = c == tile_cols - 1;
      size_t tile_col_size;

      if (!is_last) {
        tile_col_size = mem_get_varsize(data, tile_col_size_bytes);
        data += tile_col_size_bytes;
        tile_col_data_end[c] = data + tile_col_size;
      } else {
        tile_col_size = data_end - data;
        tile_col_data_end[c] = data_end;
      }
      data += tile_col_size;
    }

    data = data_start;

    // Read the required tile sizes.
    for (int c = tile_cols_start; c < tile_cols_end; ++c) {
      const int is_last = c == tile_cols - 1;

      if (c > 0) data = tile_col_data_end[c - 1];

      if (!is_last) data += tile_col_size_bytes;

      // Get the whole of the last column, otherwise stop at the required tile.
      for (int r = 0; r < (is_last ? tile_rows : tile_rows_end); ++r) {
        tile_buffers[r][c].col = c;

        get_ls_tile_buffer(tile_col_data_end[c], &pbi->common.error, &data,
                           tile_buffers, tile_size_bytes, c, r, tile_copy_mode);
      }
    }

    // If we have not read the last column, then read it to get the last tile.
    if (tile_cols_end != tile_cols) {
      int c = tile_cols - 1;

      data = tile_col_data_end[c - 1];

      for (int r = 0; r < tile_rows; ++r) {
        tile_buffers[r][c].col = c;

        get_ls_tile_buffer(tile_col_data_end[c], &pbi->common.error, &data,
                           tile_buffers, tile_size_bytes, c, r, tile_copy_mode);
      }
    }
  }
}

// Reads the next tile returning its size and adjusting '*data' accordingly
// based on 'is_last'.
static void get_tile_buffer(const uint8_t *const data_end,
                            const int tile_size_bytes, int is_last,
                            struct aom_internal_error_info *error_info,
                            const uint8_t **data, TileBufferDec *const buf) {
  size_t size;

  if (!is_last) {
    if (!read_is_valid(*data, tile_size_bytes, data_end))
      aom_internal_error(error_info, AOM_CODEC_CORRUPT_FRAME,
                         "Truncated packet or corrupt tile length");

    size = mem_get_varsize(*data, tile_size_bytes);
    *data += tile_size_bytes;

    if (size > (size_t)(data_end - *data))
      aom_internal_error(error_info, AOM_CODEC_CORRUPT_FRAME,
                         "Truncated packet or corrupt tile size");
  } else {
    size = data_end - *data;
  }

  buf->data = *data;
  buf->size = size;

  *data += size;
}

static void get_tile_buffers(AV1Decoder *pbi, const uint8_t *data,
                             const uint8_t *data_end,
                             TileBufferDec (*const tile_buffers)[MAX_TILE_COLS],
                             int startTile, int endTile) {
  AV1_COMMON *const cm = &pbi->common;
  const int tile_cols = cm->tile_cols;
  const int tile_rows = cm->tile_rows;
  int tc = 0;
  int first_tile_in_tg = 0;

#if CONFIG_DEPENDENT_HORZTILES
  int tile_group_start_col = 0;
  int tile_group_start_row = 0;
#endif

  if (startTile == 0) {
    cm->largest_tile_size = 0;
    cm->largest_tile_id = 0;
  }

  for (int r = 0; r < tile_rows; ++r) {
    for (int c = 0; c < tile_cols; ++c, ++tc) {
      TileBufferDec *const buf = &tile_buffers[r][c];

      const int is_last = (tc == endTile);
      const size_t hdr_offset = 0;

      if (tc < startTile || tc > endTile) continue;

      if (data + hdr_offset >= data_end)
        aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                           "Data ended before all tiles were read.");
      buf->col = c;
#if CONFIG_DEPENDENT_HORZTILES
      if (tc == startTile) {
        tile_group_start_row = r;
        tile_group_start_col = c;
      }
#endif  // CONFIG_DEPENDENT_HORZTILES
      first_tile_in_tg += tc == first_tile_in_tg ? pbi->tg_size : 0;
      data += hdr_offset;
      get_tile_buffer(data_end, pbi->tile_size_bytes, is_last,
                      &pbi->common.error, &data, buf);
#if CONFIG_DEPENDENT_HORZTILES
      cm->tile_group_start_row[r][c] = tile_group_start_row;
      cm->tile_group_start_col[r][c] = tile_group_start_col;
#endif
      if (buf->size > cm->largest_tile_size) {
        cm->largest_tile_size = buf->size;
        cm->largest_tile_id = r * tile_cols + c;
      }
    }
  }
}

#if CONFIG_LOOPFILTERING_ACROSS_TILES || CONFIG_LOOPFILTERING_ACROSS_TILES_EXT
static void dec_setup_across_tile_boundary_info(
    const AV1_COMMON *const cm, const TileInfo *const tile_info) {
  if (tile_info->mi_row_start >= tile_info->mi_row_end ||
      tile_info->mi_col_start >= tile_info->mi_col_end)
    return;
#if CONFIG_LOOPFILTERING_ACROSS_TILES_EXT
  if (!cm->loop_filter_across_tiles_v_enabled ||
      !cm->loop_filter_across_tiles_h_enabled) {
#else
  if (!cm->loop_filter_across_tiles_enabled) {
#endif
    av1_setup_across_tile_boundary_info(cm, tile_info);
  }
}
#endif  // CONFIG_LOOPFILTERING_ACROSS_TILES

static const uint8_t *decode_tiles(AV1Decoder *pbi, const uint8_t *data,
                                   const uint8_t *data_end, int startTile,
                                   int endTile) {
  AV1_COMMON *const cm = &pbi->common;
  const int num_planes = av1_num_planes(cm);
  const int tile_cols = cm->tile_cols;
  const int tile_rows = cm->tile_rows;
  const int n_tiles = tile_cols * tile_rows;
  TileBufferDec(*const tile_buffers)[MAX_TILE_COLS] = pbi->tile_buffers;
  const int dec_tile_row = AOMMIN(pbi->dec_tile_row, tile_rows);
  const int single_row = pbi->dec_tile_row >= 0;
  const int dec_tile_col = AOMMIN(pbi->dec_tile_col, tile_cols);
  const int single_col = pbi->dec_tile_col >= 0;
  int tile_rows_start;
  int tile_rows_end;
  int tile_cols_start;
  int tile_cols_end;
  int inv_col_order;
  int inv_row_order;
  int tile_row, tile_col;
  uint8_t allow_update_cdf;

  if (cm->large_scale_tile) {
    tile_rows_start = single_row ? dec_tile_row : 0;
    tile_rows_end = single_row ? dec_tile_row + 1 : tile_rows;
    tile_cols_start = single_col ? dec_tile_col : 0;
    tile_cols_end = single_col ? tile_cols_start + 1 : tile_cols;
    inv_col_order = pbi->inv_tile_order && !single_col;
    inv_row_order = pbi->inv_tile_order && !single_row;
    allow_update_cdf = 0;
  } else {
    tile_rows_start = 0;
    tile_rows_end = tile_rows;
    tile_cols_start = 0;
    tile_cols_end = tile_cols;
    inv_col_order = pbi->inv_tile_order;
    inv_row_order = pbi->inv_tile_order;
    allow_update_cdf = 1;
  }

  // No tiles to decode.
  if (tile_rows_end <= tile_rows_start || tile_cols_end <= tile_cols_start)
    return data;

#if CONFIG_CDF_UPDATE_MODE
  allow_update_cdf = allow_update_cdf && !cm->disable_cdf_update;
#endif  // CONFIG_CDF_UPDATE_MODE

  assert(tile_rows <= MAX_TILE_ROWS);
  assert(tile_cols <= MAX_TILE_COLS);

  if (cm->large_scale_tile)
    get_ls_tile_buffers(pbi, data, data_end, tile_buffers);
  else
    get_tile_buffers(pbi, data, data_end, tile_buffers, startTile, endTile);

  if (pbi->tile_data == NULL || n_tiles != pbi->allocated_tiles) {
    aom_free(pbi->tile_data);
    CHECK_MEM_ERROR(cm, pbi->tile_data,
                    aom_memalign(32, n_tiles * (sizeof(*pbi->tile_data))));
    pbi->allocated_tiles = n_tiles;
  }
#if CONFIG_ACCOUNTING
  if (pbi->acct_enabled) {
    aom_accounting_reset(&pbi->accounting);
  }
#endif
  // Load all tile information into tile_data.
  for (tile_row = tile_rows_start; tile_row < tile_rows_end; ++tile_row) {
    for (tile_col = tile_cols_start; tile_col < tile_cols_end; ++tile_col) {
      const TileBufferDec *const buf = &tile_buffers[tile_row][tile_col];
      TileData *const td = pbi->tile_data + tile_cols * tile_row + tile_col;

      if (tile_row * cm->tile_cols + tile_col < startTile ||
          tile_row * cm->tile_cols + tile_col > endTile)
        continue;

      td->cm = cm;
      td->xd = pbi->mb;
      td->xd.corrupted = 0;
      td->xd.counts = NULL;
      av1_zero(td->dqcoeff);
      av1_tile_init(&td->xd.tile, td->cm, tile_row, tile_col);
      setup_bool_decoder(buf->data, data_end, buf->size, &cm->error,
                         &td->bit_reader, allow_update_cdf);
#if CONFIG_ACCOUNTING
      if (pbi->acct_enabled) {
        td->bit_reader.accounting = &pbi->accounting;
      } else {
        td->bit_reader.accounting = NULL;
      }
#endif
      av1_init_macroblockd(cm, &td->xd, td->dqcoeff);

      // Initialise the tile context from the frame context
      td->tctx = *cm->fc;
      td->xd.tile_ctx = &td->tctx;
      td->xd.plane[0].color_index_map = td->color_index_map[0];
      td->xd.plane[1].color_index_map = td->color_index_map[1];
    }
  }

  for (tile_row = tile_rows_start; tile_row < tile_rows_end; ++tile_row) {
    const int row = inv_row_order ? tile_rows - 1 - tile_row : tile_row;
    int mi_row = 0;
    TileInfo tile_info;

    av1_tile_set_row(&tile_info, cm, row);

    for (tile_col = tile_cols_start; tile_col < tile_cols_end; ++tile_col) {
      const int col = inv_col_order ? tile_cols - 1 - tile_col : tile_col;
      TileData *const td = pbi->tile_data + tile_cols * row + col;

      if (tile_row * cm->tile_cols + tile_col < startTile ||
          tile_row * cm->tile_cols + tile_col > endTile)
        continue;

#if CONFIG_ACCOUNTING
      if (pbi->acct_enabled) {
        td->bit_reader.accounting->last_tell_frac =
            aom_reader_tell_frac(&td->bit_reader);
      }
#endif

      av1_tile_set_col(&tile_info, cm, col);

#if CONFIG_DEPENDENT_HORZTILES
      av1_tile_set_tg_boundary(&tile_info, cm, tile_row, tile_col);
      if (!cm->dependent_horz_tiles || tile_row == 0 ||
          tile_info.tg_horz_boundary) {
        av1_zero_above_context(cm, tile_info.mi_col_start,
                               tile_info.mi_col_end);
      }
#else
      av1_zero_above_context(cm, tile_info.mi_col_start, tile_info.mi_col_end);
#endif
      av1_reset_loop_restoration(&td->xd, num_planes);

#if CONFIG_LOOPFILTERING_ACROSS_TILES || CONFIG_LOOPFILTERING_ACROSS_TILES_EXT
      dec_setup_across_tile_boundary_info(cm, &tile_info);
#endif  // CONFIG_LOOPFILTERING_ACROSS_TILES

      for (mi_row = tile_info.mi_row_start; mi_row < tile_info.mi_row_end;
           mi_row += cm->seq_params.mib_size) {
        av1_zero_left_context(&td->xd);

        for (int mi_col = tile_info.mi_col_start; mi_col < tile_info.mi_col_end;
             mi_col += cm->seq_params.mib_size) {
          decode_partition(pbi, &td->xd, mi_row, mi_col, &td->bit_reader,
                           cm->seq_params.sb_size);
        }
        aom_merge_corrupted_flag(&pbi->mb.corrupted, td->xd.corrupted);
        if (pbi->mb.corrupted)
          aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                             "Failed to decode tile data");
      }
    }
  }

  if (!(cm->allow_intrabc && NO_FILTER_FOR_IBC)) {
    // Loopfilter the whole frame.
    if (endTile == cm->tile_rows * cm->tile_cols - 1)
      if (cm->lf.filter_level[0] || cm->lf.filter_level[1]) {
        av1_loop_filter_frame(get_frame_new_buffer(cm), cm, &pbi->mb,
                              cm->lf.filter_level[0], cm->lf.filter_level[1], 0,
                              0);
        if (num_planes > 1) {
          av1_loop_filter_frame(get_frame_new_buffer(cm), cm, &pbi->mb,
                                cm->lf.filter_level_u, cm->lf.filter_level_u, 1,
                                0);
          av1_loop_filter_frame(get_frame_new_buffer(cm), cm, &pbi->mb,
                                cm->lf.filter_level_v, cm->lf.filter_level_v, 2,
                                0);
        }
      }
  }

  if (cm->large_scale_tile) {
    if (n_tiles == 1) {
      // Find the end of the single tile buffer
      return aom_reader_find_end(&pbi->tile_data->bit_reader);
    }
    // Return the end of the last tile buffer
    return tile_buffers[tile_rows - 1][tile_cols - 1].raw_data_end;
  }

  TileData *const td = pbi->tile_data + endTile;

  return aom_reader_find_end(&td->bit_reader);
}

static void error_handler(void *data) {
  AV1_COMMON *const cm = (AV1_COMMON *)data;
  aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME, "Truncated packet");
}

void av1_read_bitdepth(AV1_COMMON *cm, struct aom_read_bit_buffer *rb) {
  cm->bit_depth = aom_rb_read_bit(rb) ? AOM_BITS_10 : AOM_BITS_8;
  if (cm->profile < PROFILE_2 || cm->bit_depth == AOM_BITS_8) {
    return;
  }
  cm->bit_depth = aom_rb_read_bit(rb) ? AOM_BITS_12 : AOM_BITS_10;
  return;
}

#if CONFIG_FILM_GRAIN
void av1_read_film_grain_params(AV1_COMMON *cm,
                                struct aom_read_bit_buffer *rb) {
  aom_film_grain_t *pars = &cm->film_grain_params;

  pars->apply_grain = aom_rb_read_bit(rb);
  if (!pars->apply_grain) {
    memset(pars, 0, sizeof(*pars));
    return;
  }

  pars->random_seed = aom_rb_read_literal(rb, 16);
  if (cm->frame_type == INTER_FRAME)
    pars->update_parameters = aom_rb_read_bit(rb);
  else
    pars->update_parameters = 1;

#if CONFIG_FILM_GRAIN_SHOWEX
  if (!pars->update_parameters) {
    // inherit parameters from a previous reference frame
    RefCntBuffer *const frame_bufs = cm->buffer_pool->frame_bufs;
    int film_grain_params_ref_idx = aom_rb_read_literal(rb, 3);
    int buf_idx = cm->ref_frame_map[film_grain_params_ref_idx];
    if (!frame_bufs[buf_idx].film_grain_params_present) {
      aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM,
                         "Film grain reference parameters not available");
    }
    uint16_t random_seed = pars->random_seed;
    *pars = frame_bufs[buf_idx].film_grain_params;  // inherit paramaters
    pars->random_seed = random_seed;                // with new random seed
    return;
  }
#else
  if (!pars->update_parameters) return;
#endif

  // Scaling functions parameters

  pars->num_y_points = aom_rb_read_literal(rb, 4);  // max 14
  if (pars->num_y_points > 14)
    aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM,
                       "Number of points for film grain luma scaling function "
                       "exceeds the maximum value.");
  for (int i = 0; i < pars->num_y_points; i++) {
    pars->scaling_points_y[i][0] = aom_rb_read_literal(rb, 8);
    if (i && pars->scaling_points_y[i - 1][0] >= pars->scaling_points_y[i][0])
      aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM,
                         "First coordinateg of the scaling function points "
                         "shall be increasing.");
    pars->scaling_points_y[i][1] = aom_rb_read_literal(rb, 8);
  }

  if (!cm->seq_params.monochrome)
    pars->chroma_scaling_from_luma = aom_rb_read_bit(rb);

  if (cm->seq_params.monochrome || pars->chroma_scaling_from_luma) {
    pars->num_cb_points = 0;
    pars->num_cr_points = 0;
  } else {
    pars->num_cb_points = aom_rb_read_literal(rb, 4);  // max 10
    if (pars->num_cb_points > 10)
      aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM,
                         "Number of points for film grain cb scaling function "
                         "exceeds the maximum value.");
    for (int i = 0; i < pars->num_cb_points; i++) {
      pars->scaling_points_cb[i][0] = aom_rb_read_literal(rb, 8);
      if (i &&
          pars->scaling_points_cb[i - 1][0] >= pars->scaling_points_cb[i][0])
        aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM,
                           "First coordinate of the scaling function points "
                           "shall be increasing.");
      pars->scaling_points_cb[i][1] = aom_rb_read_literal(rb, 8);
    }

    pars->num_cr_points = aom_rb_read_literal(rb, 4);  // max 10
    if (pars->num_cr_points > 10)
      aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM,
                         "Number of points for film grain cr scaling function "
                         "exceeds the maximum value.");
    for (int i = 0; i < pars->num_cr_points; i++) {
      pars->scaling_points_cr[i][0] = aom_rb_read_literal(rb, 8);
      if (i &&
          pars->scaling_points_cr[i - 1][0] >= pars->scaling_points_cr[i][0])
        aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM,
                           "First coordinate of the scaling function points "
                           "shall be increasing.");
      pars->scaling_points_cr[i][1] = aom_rb_read_literal(rb, 8);
    }
  }

  pars->scaling_shift = aom_rb_read_literal(rb, 2) + 8;  // 8 + value

  // AR coefficients
  // Only sent if the corresponsing scaling function has
  // more than 0 points

  pars->ar_coeff_lag = aom_rb_read_literal(rb, 2);

  int num_pos_luma = 2 * pars->ar_coeff_lag * (pars->ar_coeff_lag + 1);
  int num_pos_chroma = num_pos_luma;
  if (pars->num_y_points > 0) ++num_pos_chroma;

  if (pars->num_y_points)
    for (int i = 0; i < num_pos_luma; i++)
      pars->ar_coeffs_y[i] = aom_rb_read_literal(rb, 8) - 128;

  if (pars->num_cb_points || pars->chroma_scaling_from_luma)
    for (int i = 0; i < num_pos_chroma; i++)
      pars->ar_coeffs_cb[i] = aom_rb_read_literal(rb, 8) - 128;

  if (pars->num_cr_points || pars->chroma_scaling_from_luma)
    for (int i = 0; i < num_pos_chroma; i++)
      pars->ar_coeffs_cr[i] = aom_rb_read_literal(rb, 8) - 128;

  pars->ar_coeff_shift = aom_rb_read_literal(rb, 2) + 6;  // 6 + value

  pars->grain_scale_shift = aom_rb_read_literal(rb, 2);

  if (pars->num_cb_points) {
    pars->cb_mult = aom_rb_read_literal(rb, 8);
    pars->cb_luma_mult = aom_rb_read_literal(rb, 8);
    pars->cb_offset = aom_rb_read_literal(rb, 9);
  }

  if (pars->num_cr_points) {
    pars->cr_mult = aom_rb_read_literal(rb, 8);
    pars->cr_luma_mult = aom_rb_read_literal(rb, 8);
    pars->cr_offset = aom_rb_read_literal(rb, 9);
  }

  pars->overlap_flag = aom_rb_read_bit(rb);

  pars->clip_to_restricted_range = aom_rb_read_bit(rb);
}

static void read_film_grain(AV1_COMMON *cm, struct aom_read_bit_buffer *rb) {
  if (cm->film_grain_params_present) {
    av1_read_film_grain_params(cm, rb);
  } else {
    memset(&cm->film_grain_params, 0, sizeof(cm->film_grain_params));
  }
  cm->film_grain_params.bit_depth = cm->bit_depth;
  memcpy(&cm->cur_frame->film_grain_params, &cm->film_grain_params,
         sizeof(aom_film_grain_t));
}
#endif

void av1_read_bitdepth_colorspace_sampling(AV1_COMMON *cm,
                                           struct aom_read_bit_buffer *rb,
                                           int allow_lowbitdepth) {
  av1_read_bitdepth(cm, rb);

  cm->use_highbitdepth = cm->bit_depth > AOM_BITS_8 || !allow_lowbitdepth;
  // monochrome bit (not needed for PROFILE_1)
  const int is_monochrome = cm->profile != PROFILE_1 ? aom_rb_read_bit(rb) : 0;
  cm->seq_params.monochrome = is_monochrome;
  int color_description_present_flag = aom_rb_read_bit(rb);
  if (color_description_present_flag) {
    cm->color_primaries = aom_rb_read_literal(rb, 8);
    cm->transfer_characteristics = aom_rb_read_literal(rb, 8);
    cm->matrix_coefficients = aom_rb_read_literal(rb, 8);
  } else {
    cm->color_primaries = AOM_CICP_CP_UNSPECIFIED;
    cm->transfer_characteristics = AOM_CICP_TC_UNSPECIFIED;
    cm->matrix_coefficients = AOM_CICP_MC_UNSPECIFIED;
  }
  if (is_monochrome) {
    cm->color_range = AOM_CR_FULL_RANGE;
    cm->subsampling_y = cm->subsampling_x = 1;
    cm->chroma_sample_position = AOM_CSP_UNKNOWN;
    cm->separate_uv_delta_q = 0;
    return;
  }
  if (cm->color_primaries == AOM_CICP_CP_BT_709 &&
      cm->transfer_characteristics == AOM_CICP_TC_SRGB &&
      cm->matrix_coefficients == AOM_CICP_MC_IDENTITY) {  // it would be better
                                                          // to remove this
                                                          // dependency too
    cm->subsampling_y = cm->subsampling_x = 0;
    if (!(cm->profile == PROFILE_1 ||
          (cm->profile == PROFILE_2 && cm->bit_depth == AOM_BITS_12))) {
      aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM,
                         "SRGB colorspace not copatible with profile");
    }
  } else {
    // [16,235] (including xvycc) vs [0,255] range
    cm->color_range = aom_rb_read_bit(rb);
    if (cm->profile == PROFILE_0) {
      // 420 only
      cm->subsampling_x = cm->subsampling_y = 1;
    } else if (cm->profile == PROFILE_1) {
      // 444 only
      cm->subsampling_x = cm->subsampling_y = 0;
    } else if (cm->profile == PROFILE_2) {
      if (cm->bit_depth == AOM_BITS_12) {
        cm->subsampling_x = aom_rb_read_bit(rb);
        if (cm->subsampling_x == 0)
          cm->subsampling_y = 0;  // 444
        else
          cm->subsampling_y = aom_rb_read_bit(rb);  // 422 or 420
      } else {
        // 422
        cm->subsampling_x = 1;
        cm->subsampling_y = 0;
      }
    }
    if (cm->subsampling_x == 1 && cm->subsampling_y == 1) {
      cm->chroma_sample_position = aom_rb_read_literal(rb, 2);
    }
  }
  cm->separate_uv_delta_q = aom_rb_read_bit(rb);
}

void av1_read_timing_info_header(AV1_COMMON *cm,
                                 struct aom_read_bit_buffer *rb) {
  cm->timing_info_present = aom_rb_read_bit(rb);  // timing info present flag

  if (cm->timing_info_present) {
    cm->num_units_in_tick =
        aom_rb_read_unsigned_literal(rb, 32);  // Number of units in tick
    cm->time_scale = aom_rb_read_unsigned_literal(rb, 32);  // Time scale
    cm->equal_picture_interval =
        aom_rb_read_bit(rb);  // Equal picture interval bit
    if (cm->equal_picture_interval) {
      cm->num_ticks_per_picture =
          aom_rb_read_uvlc(rb) + 1;  // ticks per picture
    }
  }
}

void read_sequence_header(SequenceHeader *seq_params,
                          struct aom_read_bit_buffer *rb) {
  int num_bits_width = aom_rb_read_literal(rb, 4) + 1;
  int num_bits_height = aom_rb_read_literal(rb, 4) + 1;
  int max_frame_width = aom_rb_read_literal(rb, num_bits_width) + 1;
  int max_frame_height = aom_rb_read_literal(rb, num_bits_height) + 1;

  seq_params->num_bits_width = num_bits_width;
  seq_params->num_bits_height = num_bits_height;
  seq_params->max_frame_width = max_frame_width;
  seq_params->max_frame_height = max_frame_height;

  seq_params->frame_id_numbers_present_flag = aom_rb_read_bit(rb);
  if (seq_params->frame_id_numbers_present_flag) {
    // We must always have delta_frame_id_length < frame_id_length,
    // in order for a frame to be referenced with a unique delta.
    // Avoid wasting bits by using a coding that enforces this restriction.
    seq_params->delta_frame_id_length = aom_rb_read_literal(rb, 4) + 2;
    seq_params->frame_id_length =
        aom_rb_read_literal(rb, 3) + seq_params->delta_frame_id_length + 1;
  }

  setup_sb_size(seq_params, rb);

  seq_params->enable_dual_filter = aom_rb_read_bit(rb);

  seq_params->enable_order_hint = aom_rb_read_bit(rb);

  seq_params->enable_jnt_comp =
      seq_params->enable_order_hint ? aom_rb_read_bit(rb) : 0;

  if (aom_rb_read_bit(rb)) {
    seq_params->force_screen_content_tools = 2;
  } else {
    seq_params->force_screen_content_tools = aom_rb_read_bit(rb);
  }

#if CONFIG_AMVR
  if (seq_params->force_screen_content_tools > 0) {
    if (aom_rb_read_bit(rb)) {
      seq_params->force_integer_mv = 2;
    } else {
      seq_params->force_integer_mv = aom_rb_read_bit(rb);
    }
  } else {
    seq_params->force_integer_mv = 2;
  }
#endif

#if CONFIG_EXPLICIT_ORDER_HINT
  seq_params->order_hint_bits = aom_rb_read_literal(rb, 3);
#endif
}

static void read_compound_tools(AV1_COMMON *cm,
                                struct aom_read_bit_buffer *rb) {
  cm->allow_interintra_compound =
      !frame_is_intra_only(cm) ? aom_rb_read_bit(rb) : 0;

  if (!frame_is_intra_only(cm) && cm->reference_mode != SINGLE_REFERENCE) {
    cm->allow_masked_compound = aom_rb_read_bit(rb);
  } else {
    cm->allow_masked_compound = 0;
  }
}

static int read_global_motion_params(WarpedMotionParams *params,
                                     const WarpedMotionParams *ref_params,
                                     struct aom_read_bit_buffer *rb,
                                     int allow_hp) {
  TransformationType type = aom_rb_read_bit(rb);
  if (type != IDENTITY) {
#if GLOBAL_TRANS_TYPES > 4
    type += aom_rb_read_literal(rb, GLOBAL_TYPE_BITS);
#else
    if (aom_rb_read_bit(rb))
      type = ROTZOOM;
    else
      type = aom_rb_read_bit(rb) ? TRANSLATION : AFFINE;
#endif  // GLOBAL_TRANS_TYPES > 4
  }

  *params = default_warp_params;
  params->wmtype = type;

  if (type >= ROTZOOM) {
    params->wmmat[2] = aom_rb_read_signed_primitive_refsubexpfin(
                           rb, GM_ALPHA_MAX + 1, SUBEXPFIN_K,
                           (ref_params->wmmat[2] >> GM_ALPHA_PREC_DIFF) -
                               (1 << GM_ALPHA_PREC_BITS)) *
                           GM_ALPHA_DECODE_FACTOR +
                       (1 << WARPEDMODEL_PREC_BITS);
    params->wmmat[3] = aom_rb_read_signed_primitive_refsubexpfin(
                           rb, GM_ALPHA_MAX + 1, SUBEXPFIN_K,
                           (ref_params->wmmat[3] >> GM_ALPHA_PREC_DIFF)) *
                       GM_ALPHA_DECODE_FACTOR;
  }

  if (type >= AFFINE) {
    params->wmmat[4] = aom_rb_read_signed_primitive_refsubexpfin(
                           rb, GM_ALPHA_MAX + 1, SUBEXPFIN_K,
                           (ref_params->wmmat[4] >> GM_ALPHA_PREC_DIFF)) *
                       GM_ALPHA_DECODE_FACTOR;
    params->wmmat[5] = aom_rb_read_signed_primitive_refsubexpfin(
                           rb, GM_ALPHA_MAX + 1, SUBEXPFIN_K,
                           (ref_params->wmmat[5] >> GM_ALPHA_PREC_DIFF) -
                               (1 << GM_ALPHA_PREC_BITS)) *
                           GM_ALPHA_DECODE_FACTOR +
                       (1 << WARPEDMODEL_PREC_BITS);
  } else {
    params->wmmat[4] = -params->wmmat[3];
    params->wmmat[5] = params->wmmat[2];
  }

  if (type >= TRANSLATION) {
    const int trans_bits = (type == TRANSLATION)
                               ? GM_ABS_TRANS_ONLY_BITS - !allow_hp
                               : GM_ABS_TRANS_BITS;
    const int trans_dec_factor =
        (type == TRANSLATION) ? GM_TRANS_ONLY_DECODE_FACTOR * (1 << !allow_hp)
                              : GM_TRANS_DECODE_FACTOR;
    const int trans_prec_diff = (type == TRANSLATION)
                                    ? GM_TRANS_ONLY_PREC_DIFF + !allow_hp
                                    : GM_TRANS_PREC_DIFF;
    params->wmmat[0] = aom_rb_read_signed_primitive_refsubexpfin(
                           rb, (1 << trans_bits) + 1, SUBEXPFIN_K,
                           (ref_params->wmmat[0] >> trans_prec_diff)) *
                       trans_dec_factor;
    params->wmmat[1] = aom_rb_read_signed_primitive_refsubexpfin(
                           rb, (1 << trans_bits) + 1, SUBEXPFIN_K,
                           (ref_params->wmmat[1] >> trans_prec_diff)) *
                       trans_dec_factor;
  }

  if (params->wmtype <= AFFINE) {
    int good_shear_params = get_shear_params(params);
    if (!good_shear_params) return 0;
  }

  return 1;
}

static void read_global_motion(AV1_COMMON *cm, struct aom_read_bit_buffer *rb) {
  for (int frame = LAST_FRAME; frame <= ALTREF_FRAME; ++frame) {
    const WarpedMotionParams *ref_params =
        cm->error_resilient_mode ? &default_warp_params
                                 : &cm->prev_frame->global_motion[frame];
    int good_params = read_global_motion_params(
        &cm->global_motion[frame], ref_params, rb, cm->allow_high_precision_mv);
    if (!good_params) {
#if WARPED_MOTION_DEBUG
      printf("Warning: unexpected global motion shear params from aomenc\n");
#endif
      cm->global_motion[frame].invalid = 1;
    }

    // TODO(sarahparker, debargha): The logic in the commented out code below
    // does not work currently and causes mismatches when resize is on. Fix it
    // before turning the optimization back on.
    /*
    YV12_BUFFER_CONFIG *ref_buf = get_ref_frame(cm, frame);
    if (cm->width == ref_buf->y_crop_width &&
        cm->height == ref_buf->y_crop_height) {
      read_global_motion_params(&cm->global_motion[frame],
                                &cm->prev_frame->global_motion[frame], rb,
                                cm->allow_high_precision_mv);
    } else {
      cm->global_motion[frame] = default_warp_params;
    }
    */
    /*
    printf("Dec Ref %d [%d/%d]: %d %d %d %d\n",
           frame, cm->current_video_frame, cm->show_frame,
           cm->global_motion[frame].wmmat[0],
           cm->global_motion[frame].wmmat[1],
           cm->global_motion[frame].wmmat[2],
           cm->global_motion[frame].wmmat[3]);
           */
  }
  memcpy(cm->cur_frame->global_motion, cm->global_motion,
         TOTAL_REFS_PER_FRAME * sizeof(WarpedMotionParams));
}

// Copied from av1/encoder/random.h
static INLINE unsigned int lcg_rand16(unsigned int *state) {
  *state = (unsigned int)(*state * 1103515245ULL + 12345);
  return *state / 65536 % 32768;
}

#if !CONFIG_EXPLICIT_ORDER_HINT
// Wrap around to make sure current_video_frame won't surpass a limit
// Such that distance computation could remain correct
static void wrap_around_current_video_frame(AV1Decoder *pbi) {
  AV1_COMMON *const cm = &pbi->common;

  if (cm->current_video_frame >= FRAME_NUM_LIMIT) {
    // Wrap to a random number in range (MAX_FRAME_DISTANCE, 32768)
    static unsigned int seed = 54321;
    int new_frame_offset = lcg_rand16(&seed);
    new_frame_offset += (MAX_FRAME_DISTANCE + 1);

    // Wrap around for current frame
    cm->current_video_frame = new_frame_offset;
    cm->frame_offset = new_frame_offset;
    cm->cur_frame->cur_frame_offset = cm->frame_offset;
  }
}
#endif

#if CONFIG_FWD_KF
static void show_existing_frame_reset(AV1Decoder *const pbi,
                                      int existing_frame_idx) {
  AV1_COMMON *const cm = &pbi->common;
  BufferPool *const pool = cm->buffer_pool;
  RefCntBuffer *const frame_bufs = pool->frame_bufs;

  assert(cm->show_existing_frame);

#if !CONFIG_EXPLICIT_ORDER_HINT
  wrap_around_current_video_frame(pbi);
#endif
  cm->frame_type = KEY_FRAME;
#if !CONFIG_EXPLICIT_ORDER_HINT
  cm->frame_offset = cm->current_video_frame;
#endif

  pbi->refresh_frame_flags = (1 << REF_FRAMES) - 1;

  for (int i = 0; i < INTER_REFS_PER_FRAME; ++i) {
    cm->frame_refs[i].idx = INVALID_IDX;
    cm->frame_refs[i].buf = NULL;
  }

  if (pbi->need_resync) {
    memset(&cm->ref_frame_map, -1, sizeof(cm->ref_frame_map));
    pbi->need_resync = 0;
  }

#if !CONFIG_NO_FRAME_CONTEXT_SIGNALING
  cm->reset_frame_context = RESET_FRAME_CONTEXT_ALL;
#endif  // !CONFIG_NO_FRAME_CONTEXT_SIGNALING

  cm->cur_frame->intra_only = 1;

  if (cm->seq_params.frame_id_numbers_present_flag) {
    /* If bitmask is set, update reference frame id values and
       mark frames as valid for reference */
    int refresh_frame_flags = pbi->refresh_frame_flags;
    for (int i = 0; i < REF_FRAMES; i++) {
      if ((refresh_frame_flags >> i) & 1) {
        cm->ref_frame_id[i] = cm->current_frame_id;
        cm->valid_for_referencing[i] = 1;
      }
    }
  }

  cm->refresh_frame_context = REFRESH_FRAME_CONTEXT_DISABLED;

  // Generate next_ref_frame_map.
  lock_buffer_pool(pool);
  int ref_index = 0;
  for (int mask = pbi->refresh_frame_flags; mask; mask >>= 1) {
    if (mask & 1) {
      cm->next_ref_frame_map[ref_index] = cm->new_fb_idx;
      ++frame_bufs[cm->new_fb_idx].ref_count;
    } else {
      cm->next_ref_frame_map[ref_index] = cm->ref_frame_map[ref_index];
    }
    // Current thread holds the reference frame.
    if (cm->ref_frame_map[ref_index] >= 0)
      ++frame_bufs[cm->ref_frame_map[ref_index]].ref_count;
    ++ref_index;
  }

  for (; ref_index < REF_FRAMES; ++ref_index) {
    cm->next_ref_frame_map[ref_index] = cm->ref_frame_map[ref_index];

    // Current thread holds the reference frame.
    if (cm->ref_frame_map[ref_index] >= 0)
      ++frame_bufs[cm->ref_frame_map[ref_index]].ref_count;
  }
  unlock_buffer_pool(pool);
  pbi->hold_ref_buf = 1;

  // Reload the adapted CDFs from when we originally coded this keyframe
  *cm->fc = cm->frame_contexts[existing_frame_idx];
}
#endif  // CONFIG_FWD_KF

static int read_uncompressed_header(AV1Decoder *pbi,
                                    struct aom_read_bit_buffer *rb) {
  AV1_COMMON *const cm = &pbi->common;
  MACROBLOCKD *const xd = &pbi->mb;
  BufferPool *const pool = cm->buffer_pool;
  RefCntBuffer *const frame_bufs = pool->frame_bufs;

  cm->last_frame_type = cm->frame_type;
  cm->last_intra_only = cm->intra_only;

  // NOTE: By default all coded frames to be used as a reference
  cm->is_reference_frame = 1;

  cm->show_existing_frame = aom_rb_read_bit(rb);
#if CONFIG_FWD_KF
  cm->reset_decoder_state = 0;
#endif  // CONFIG_FWD_KF

  if (cm->show_existing_frame) {
    // Show an existing frame directly.
    const int existing_frame_idx = aom_rb_read_literal(rb, 3);
    const int frame_to_show = cm->ref_frame_map[existing_frame_idx];
    if (cm->seq_params.frame_id_numbers_present_flag) {
      int frame_id_length = cm->seq_params.frame_id_length;
      int display_frame_id = aom_rb_read_literal(rb, frame_id_length);
      /* Compare display_frame_id with ref_frame_id and check valid for
       * referencing */
      if (display_frame_id != cm->ref_frame_id[existing_frame_idx] ||
          cm->valid_for_referencing[existing_frame_idx] == 0)
        aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                           "Reference buffer frame ID mismatch");
#if CONFIG_FWD_KF
      cm->current_frame_id = display_frame_id;
#endif  // CONFIG_FWD_KF
    }
    lock_buffer_pool(pool);
    if (frame_to_show < 0 || frame_bufs[frame_to_show].ref_count < 1) {
      unlock_buffer_pool(pool);
      aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM,
                         "Buffer %d does not contain a decoded frame",
                         frame_to_show);
    }
    ref_cnt_fb(frame_bufs, &cm->new_fb_idx, frame_to_show);
#if CONFIG_FWD_KF
    cm->reset_decoder_state = frame_bufs[frame_to_show].frame_type == KEY_FRAME;
#endif  // CONFIG_FWD_KF
    unlock_buffer_pool(pool);

    cm->lf.filter_level[0] = 0;
    cm->lf.filter_level[1] = 0;
    cm->show_frame = 1;

#if CONFIG_FILM_GRAIN_SHOWEX
    if (!frame_bufs[frame_to_show].showable_frame) {
      aom_merge_corrupted_flag(&xd->corrupted, 1);
    }
    frame_bufs[frame_to_show].showable_frame = 0;
#endif
#if CONFIG_FILM_GRAIN
#if CONFIG_FILM_GRAIN_SHOWEX
    cm->film_grain_params = frame_bufs[frame_to_show].film_grain_params;
#else
    read_film_grain(cm, rb);
#endif
#endif

#if CONFIG_FWD_KF
    if (cm->reset_decoder_state) {
      show_existing_frame_reset(pbi, existing_frame_idx);
    } else {
#endif  // CONFIG_FWD_KF
      pbi->refresh_frame_flags = 0;
#if CONFIG_FWD_KF
    }
#endif  // CONFIG_FWD_KF

    return 0;
  }

  cm->frame_type = (FRAME_TYPE)aom_rb_read_literal(rb, 2);  // 2 bits
  cm->show_frame = aom_rb_read_bit(rb);
  cm->intra_only = cm->frame_type == INTRA_ONLY_FRAME;
  cm->error_resilient_mode = aom_rb_read_bit(rb);
  cm->enable_intra_edge_filter = aom_rb_read_bit(rb);
  cm->allow_filter_intra = aom_rb_read_bit(rb);

#if CONFIG_CDF_UPDATE_MODE
  cm->disable_cdf_update = aom_rb_read_bit(rb);
#endif  // CONFIG_CDF_UPDATE_MODE

  if (cm->seq_params.force_screen_content_tools == 2) {
    cm->allow_screen_content_tools = aom_rb_read_bit(rb);
  } else {
    cm->allow_screen_content_tools = cm->seq_params.force_screen_content_tools;
  }

#if CONFIG_AMVR
  if (cm->allow_screen_content_tools) {
    if (cm->seq_params.force_integer_mv == 2) {
      cm->cur_frame_force_integer_mv = aom_rb_read_bit(rb);
    } else {
      cm->cur_frame_force_integer_mv = cm->seq_params.force_integer_mv;
    }
  } else {
    cm->cur_frame_force_integer_mv = 0;
  }
#endif  // CONFIG_AMVR

  if (cm->seq_params.frame_id_numbers_present_flag) {
    int frame_id_length = cm->seq_params.frame_id_length;
    int diff_len = cm->seq_params.delta_frame_id_length;
    int prev_frame_id = 0;
    if (cm->frame_type != KEY_FRAME) {
      prev_frame_id = cm->current_frame_id;
    }
    cm->current_frame_id = aom_rb_read_literal(rb, frame_id_length);

    if (cm->frame_type != KEY_FRAME) {
      int diff_frame_id;
      if (cm->current_frame_id > prev_frame_id) {
        diff_frame_id = cm->current_frame_id - prev_frame_id;
      } else {
        diff_frame_id =
            (1 << frame_id_length) + cm->current_frame_id - prev_frame_id;
      }
      /* Check current_frame_id for conformance */
      if (prev_frame_id == cm->current_frame_id ||
          diff_frame_id >= (1 << (frame_id_length - 1))) {
        aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                           "Invalid value of current_frame_id");
      }
    }
    /* Check if some frames need to be marked as not valid for referencing */
    for (int i = 0; i < REF_FRAMES; i++) {
      if (cm->frame_type == KEY_FRAME) {
        cm->valid_for_referencing[i] = 0;
      } else if (cm->current_frame_id - (1 << diff_len) > 0) {
        if (cm->ref_frame_id[i] > cm->current_frame_id ||
            cm->ref_frame_id[i] < cm->current_frame_id - (1 << diff_len))
          cm->valid_for_referencing[i] = 0;
      } else {
        if (cm->ref_frame_id[i] > cm->current_frame_id &&
            cm->ref_frame_id[i] <
                (1 << frame_id_length) + cm->current_frame_id - (1 << diff_len))
          cm->valid_for_referencing[i] = 0;
      }
    }
  }

  int frame_size_override_flag = aom_rb_read_literal(rb, 1);
  cm->allow_intrabc = 0;

#if CONFIG_FRAME_REFS_SIGNALING
  cm->frame_refs_short_signaling = 0;
#endif  // CONFIG_FRAME_REFS_SIGNALING
#if CONFIG_NO_FRAME_CONTEXT_SIGNALING
  cm->primary_ref_frame = PRIMARY_REF_NONE;
#endif  // CONFIG_NO_FRAME_CONTEXT_SIGNALING

#if CONFIG_EXPLICIT_ORDER_HINT
  cm->frame_offset = aom_rb_read_literal(rb, cm->seq_params.order_hint_bits);
  cm->current_video_frame = cm->frame_offset;
#else
  if (cm->show_frame == 0) {
    cm->frame_offset =
        cm->current_video_frame + aom_rb_read_literal(rb, FRAME_OFFSET_BITS);
  } else {
    cm->frame_offset = cm->current_video_frame;
  }
#endif

  if (cm->frame_type == KEY_FRAME) {
#if !CONFIG_EXPLICIT_ORDER_HINT
    wrap_around_current_video_frame(pbi);
#endif  // !CONFIG_EXPLICIT_ORDER_HINT
#if CONFIG_FWD_KF
    if (!cm->show_frame)  // unshown keyframe (forward keyframe)
      pbi->refresh_frame_flags = aom_rb_read_literal(rb, REF_FRAMES);
    else  // shown keyframe
#endif    // CONFIG_FWD_KF
      pbi->refresh_frame_flags = (1 << REF_FRAMES) - 1;

    for (int i = 0; i < INTER_REFS_PER_FRAME; ++i) {
      cm->frame_refs[i].idx = INVALID_IDX;
      cm->frame_refs[i].buf = NULL;
    }

    setup_frame_size(cm, frame_size_override_flag, rb);

    if (pbi->need_resync) {
      memset(&cm->ref_frame_map, -1, sizeof(cm->ref_frame_map));
      pbi->need_resync = 0;
    }
    if (cm->allow_screen_content_tools &&
        (av1_superres_unscaled(cm) || !NO_FILTER_FOR_IBC))
      cm->allow_intrabc = aom_rb_read_bit(rb);
    cm->use_prev_frame_mvs = 0;
  } else {
    if (cm->intra_only || cm->error_resilient_mode) cm->use_prev_frame_mvs = 0;
#if CONFIG_NO_FRAME_CONTEXT_SIGNALING
// The only way to reset all frame contexts to their default values is with a
// keyframe.
#else
    if (cm->error_resilient_mode) {
      cm->reset_frame_context = RESET_FRAME_CONTEXT_ALL;
    } else {
      if (cm->intra_only) {
        cm->reset_frame_context = aom_rb_read_bit(rb)
                                      ? RESET_FRAME_CONTEXT_ALL
                                      : RESET_FRAME_CONTEXT_CURRENT;
      } else {
        cm->reset_frame_context = aom_rb_read_bit(rb)
                                      ? RESET_FRAME_CONTEXT_CURRENT
                                      : RESET_FRAME_CONTEXT_NONE;
        if (cm->reset_frame_context == RESET_FRAME_CONTEXT_CURRENT)
          cm->reset_frame_context = aom_rb_read_bit(rb)
                                        ? RESET_FRAME_CONTEXT_ALL
                                        : RESET_FRAME_CONTEXT_CURRENT;
      }
    }
#endif

    if (cm->intra_only) {
#if CONFIG_FILM_GRAIN
      cm->cur_frame->film_grain_params_present = cm->film_grain_params_present;
#endif
      pbi->refresh_frame_flags = aom_rb_read_literal(rb, REF_FRAMES);
      setup_frame_size(cm, frame_size_override_flag, rb);
      if (pbi->need_resync) {
        memset(&cm->ref_frame_map, -1, sizeof(cm->ref_frame_map));
        pbi->need_resync = 0;
      }
      if (cm->allow_screen_content_tools &&
          (av1_superres_unscaled(cm) || !NO_FILTER_FOR_IBC))
        cm->allow_intrabc = aom_rb_read_bit(rb);
    } else if (pbi->need_resync != 1) { /* Skip if need resync */
      pbi->refresh_frame_flags = (cm->frame_type == S_FRAME)
                                     ? 0xFF
                                     : aom_rb_read_literal(rb, REF_FRAMES);

      if (!pbi->refresh_frame_flags) {
        // NOTE: "pbi->refresh_frame_flags == 0" indicates that the coded frame
        //       will not be used as a reference
        cm->is_reference_frame = 0;
      }

#if CONFIG_FRAME_REFS_SIGNALING
      // Frame refs short signaling is off when error resilient mode is on.
      if (!cm->error_resilient_mode && cm->seq_params.enable_order_hint)
        cm->frame_refs_short_signaling = aom_rb_read_bit(rb);

      if (cm->frame_refs_short_signaling) {
        // == LAST_FRAME ==
        const int lst_ref = aom_rb_read_literal(rb, REF_FRAMES_LOG2);
        const int lst_idx = cm->ref_frame_map[lst_ref];

        // == GOLDEN_FRAME ==
        const int gld_ref = aom_rb_read_literal(rb, REF_FRAMES_LOG2);
        const int gld_idx = cm->ref_frame_map[gld_ref];

        // Most of the time, streams start with a keyframe. In that case,
        // ref_frame_map will have been filled in at that point and will not
        // contain any -1's. However, streams are explicitly allowed to start
        // with an intra-only frame, so long as they don't then signal a
        // reference to a slot that hasn't been set yet. That's what we are
        // checking here.
        if (lst_idx == -1)
          aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                             "Inter frame requests nonexistent reference");
        if (gld_idx == -1)
          aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                             "Inter frame requests nonexistent reference");

        av1_set_frame_refs(cm, lst_ref, gld_ref);
      }
#endif  // CONFIG_FRAME_REFS_SIGNALING

      for (int i = 0; i < INTER_REFS_PER_FRAME; ++i) {
        int ref = 0;
#if CONFIG_FRAME_REFS_SIGNALING
        if (!cm->frame_refs_short_signaling) {
#endif  // CONFIG_FRAME_REFS_SIGNALING
          ref = aom_rb_read_literal(rb, REF_FRAMES_LOG2);
          const int idx = cm->ref_frame_map[ref];

          // Most of the time, streams start with a keyframe. In that case,
          // ref_frame_map will have been filled in at that point and will not
          // contain any -1's. However, streams are explicitly allowed to start
          // with an intra-only frame, so long as they don't then signal a
          // reference to a slot that hasn't been set yet. That's what we are
          // checking here.
          if (idx == -1)
            aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                               "Inter frame requests nonexistent reference");

          RefBuffer *const ref_frame = &cm->frame_refs[i];
          ref_frame->idx = idx;
          ref_frame->buf = &frame_bufs[idx].buf;
#if CONFIG_FRAME_REFS_SIGNALING
          ref_frame->map_idx = ref;
        } else {
          ref = cm->frame_refs[i].map_idx;
        }
#endif  // CONFIG_FRAME_REFS_SIGNALING

        // NOTE: For the scenario of (cm->frame_type != S_FRAME),
        // ref_frame_sign_bias will be reset based on frame offsets.
        cm->ref_frame_sign_bias[LAST_FRAME + i] = 0;

        if (cm->seq_params.frame_id_numbers_present_flag) {
          int frame_id_length = cm->seq_params.frame_id_length;
          int diff_len = cm->seq_params.delta_frame_id_length;
          int delta_frame_id_minus1 = aom_rb_read_literal(rb, diff_len);
          int ref_frame_id =
              ((cm->current_frame_id - (delta_frame_id_minus1 + 1) +
                (1 << frame_id_length)) %
               (1 << frame_id_length));
          // Compare values derived from delta_frame_id_minus1 and
          // refresh_frame_flags. Also, check valid for referencing
          if (ref_frame_id != cm->ref_frame_id[ref] ||
              cm->valid_for_referencing[ref] == 0)
            aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                               "Reference buffer frame ID mismatch");
        }
      }

      if (cm->error_resilient_mode == 0 && frame_size_override_flag) {
        setup_frame_size_with_refs(cm, rb);
      } else {
        setup_frame_size(cm, frame_size_override_flag, rb);
      }

#if CONFIG_AMVR
      if (cm->cur_frame_force_integer_mv) {
        cm->allow_high_precision_mv = 0;
      } else {
        cm->allow_high_precision_mv = aom_rb_read_bit(rb);
      }
#else
      cm->allow_high_precision_mv = aom_rb_read_bit(rb);
#endif
      cm->interp_filter = read_frame_interp_filter(rb);
      cm->switchable_motion_mode = aom_rb_read_bit(rb);
      if (frame_might_use_prev_frame_mvs(cm) &&
          cm->seq_params.enable_order_hint)
        cm->use_ref_frame_mvs = aom_rb_read_bit(rb);
      else
        cm->use_ref_frame_mvs = 0;

      cm->prev_frame =
          cm->frame_refs[LAST_FRAME - LAST_FRAME].idx != INVALID_IDX
              ? &cm->buffer_pool
                     ->frame_bufs[cm->frame_refs[LAST_FRAME - LAST_FRAME].idx]
              : NULL;
      cm->use_prev_frame_mvs =
          cm->use_ref_frame_mvs && frame_can_use_prev_frame_mvs(cm);
      for (int i = 0; i < INTER_REFS_PER_FRAME; ++i) {
        RefBuffer *const ref_buf = &cm->frame_refs[i];
        av1_setup_scale_factors_for_frame(
            &ref_buf->sf, ref_buf->buf->y_crop_width,
            ref_buf->buf->y_crop_height, cm->width, cm->height);
      }
    }
  }

  av1_setup_frame_buf_refs(cm);

  if (cm->frame_type != S_FRAME && !cm->error_resilient_mode)
    av1_setup_frame_sign_bias(cm);

  cm->cur_frame->intra_only = cm->frame_type == KEY_FRAME || cm->intra_only;
  cm->cur_frame->frame_type = cm->frame_type;

  if (cm->seq_params.frame_id_numbers_present_flag) {
    /* If bitmask is set, update reference frame id values and
       mark frames as valid for reference */
    int refresh_frame_flags = pbi->refresh_frame_flags;
    for (int i = 0; i < REF_FRAMES; i++) {
      if ((refresh_frame_flags >> i) & 1) {
        cm->ref_frame_id[i] = cm->current_frame_id;
        cm->valid_for_referencing[i] = 1;
      }
    }
  }

  get_frame_new_buffer(cm)->bit_depth = cm->bit_depth;
  get_frame_new_buffer(cm)->color_primaries = cm->color_primaries;
  get_frame_new_buffer(cm)->transfer_characteristics =
      cm->transfer_characteristics;
  get_frame_new_buffer(cm)->matrix_coefficients = cm->matrix_coefficients;
  get_frame_new_buffer(cm)->monochrome = cm->seq_params.monochrome;
  get_frame_new_buffer(cm)->chroma_sample_position = cm->chroma_sample_position;
  get_frame_new_buffer(cm)->color_range = cm->color_range;
  get_frame_new_buffer(cm)->render_width = cm->render_width;
  get_frame_new_buffer(cm)->render_height = cm->render_height;

  if (pbi->need_resync) {
    aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                       "Keyframe / intra-only frame required to reset decoder"
                       " state");
  }

  const int might_bwd_adapt =
      !(cm->error_resilient_mode || cm->large_scale_tile);
  if (might_bwd_adapt) {
    cm->refresh_frame_context = aom_rb_read_bit(rb)
                                    ? REFRESH_FRAME_CONTEXT_DISABLED
                                    : REFRESH_FRAME_CONTEXT_BACKWARD;
  } else {
    cm->refresh_frame_context = REFRESH_FRAME_CONTEXT_DISABLED;
  }
#if !CONFIG_NO_FRAME_CONTEXT_SIGNALING
  // This flag will be overridden by the call to av1_setup_past_independence
  // below, forcing the use of context 0 for those frame types.
  cm->frame_context_idx = aom_rb_read_literal(rb, FRAME_CONTEXTS_LOG2);
#else
  if (!cm->error_resilient_mode && !frame_is_intra_only(cm)) {
    cm->primary_ref_frame = aom_rb_read_literal(rb, PRIMARY_REF_BITS);
    if (cm->primary_ref_frame != PRIMARY_REF_NONE &&
        cm->frame_refs[cm->primary_ref_frame].idx < 0) {
      aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                         "Reference frame containing this frame's initial "
                         "frame context is unavailable.");
    }
  }
#endif

  // Generate next_ref_frame_map.
  lock_buffer_pool(pool);
  int ref_index = 0;
  for (int mask = pbi->refresh_frame_flags; mask; mask >>= 1) {
    if (mask & 1) {
      cm->next_ref_frame_map[ref_index] = cm->new_fb_idx;
      ++frame_bufs[cm->new_fb_idx].ref_count;
    } else {
      cm->next_ref_frame_map[ref_index] = cm->ref_frame_map[ref_index];
    }
    // Current thread holds the reference frame.
    if (cm->ref_frame_map[ref_index] >= 0)
      ++frame_bufs[cm->ref_frame_map[ref_index]].ref_count;
    ++ref_index;
  }

  for (; ref_index < REF_FRAMES; ++ref_index) {
    cm->next_ref_frame_map[ref_index] = cm->ref_frame_map[ref_index];

    // Current thread holds the reference frame.
    if (cm->ref_frame_map[ref_index] >= 0)
      ++frame_bufs[cm->ref_frame_map[ref_index]].ref_count;
  }
  unlock_buffer_pool(pool);
  pbi->hold_ref_buf = 1;

  if (cm->allow_intrabc && NO_FILTER_FOR_IBC) {
    // Set parameters corresponding to no filtering.
    struct loopfilter *lf = &cm->lf;
    lf->filter_level[0] = 0;
    lf->filter_level[1] = 0;
    cm->cdef_bits = 0;
    cm->cdef_strengths[0] = 0;
    cm->nb_cdef_strengths = 1;
    cm->cdef_uv_strengths[0] = 0;
    cm->rst_info[0].frame_restoration_type = RESTORE_NONE;
    cm->rst_info[1].frame_restoration_type = RESTORE_NONE;
    cm->rst_info[2].frame_restoration_type = RESTORE_NONE;
  }

#if CONFIG_TILE_INFO_FIRST
  read_tile_info(pbi, rb);
#endif

  setup_quantization(cm, rb);
  xd->bd = (int)cm->bit_depth;

  if (frame_is_intra_only(cm) || cm->error_resilient_mode) {
    av1_setup_past_independence(cm);
    av1_setup_frame_contexts(cm);
  }
#if CONFIG_NO_FRAME_CONTEXT_SIGNALING
  else if (cm->primary_ref_frame == PRIMARY_REF_NONE) {
    // The default coefficient CDFs depend on base_qindex. So, in order to
    // ensure that we don't depend on the frame decoding order, we explicitly
    // reset the coefficient CDFs with the value of base_qindex for this frame.
    *cm->fc = cm->frame_contexts[FRAME_CONTEXT_DEFAULTS];
    av1_default_coef_probs(cm);
    cm->frame_contexts[FRAME_CONTEXT_DEFAULTS] = *cm->fc;
  }
#endif  // CONFIG_NO_FRAME_CONTEXT_SIGNALING

  setup_segmentation(cm, rb);

  {
    int delta_q_allowed = 1;
#if !CONFIG_EXT_DELTA_Q
    struct segmentation *const seg = &cm->seg;
    int segment_quantizer_active = 0;
    for (int i = 0; i < MAX_SEGMENTS; i++) {
      if (segfeature_active(seg, i, SEG_LVL_ALT_Q)) {
        segment_quantizer_active = 1;
      }
    }
    delta_q_allowed = !segment_quantizer_active;
#endif

    cm->delta_q_res = 1;
#if CONFIG_EXT_DELTA_Q
    cm->delta_lf_res = 1;
    cm->delta_lf_present_flag = 0;
    cm->delta_lf_multi = 0;
#endif
    if (delta_q_allowed == 1 && cm->base_qindex > 0) {
      cm->delta_q_present_flag = aom_rb_read_bit(rb);
    } else {
      cm->delta_q_present_flag = 0;
    }
    if (cm->delta_q_present_flag) {
      xd->prev_qindex = cm->base_qindex;
      cm->delta_q_res = 1 << aom_rb_read_literal(rb, 2);
#if CONFIG_EXT_DELTA_Q
      if (!cm->allow_intrabc || !NO_FILTER_FOR_IBC)
        cm->delta_lf_present_flag = aom_rb_read_bit(rb);
      if (cm->delta_lf_present_flag) {
        xd->prev_delta_lf_from_base = 0;
        cm->delta_lf_res = 1 << aom_rb_read_literal(rb, 2);
        cm->delta_lf_multi = aom_rb_read_bit(rb);
        const int frame_lf_count =
            av1_num_planes(cm) > 1 ? FRAME_LF_COUNT : FRAME_LF_COUNT - 2;
        for (int lf_id = 0; lf_id < frame_lf_count; ++lf_id)
          xd->prev_delta_lf[lf_id] = 0;
      }
#endif  // CONFIG_EXT_DELTA_Q
    }
  }
#if CONFIG_AMVR
  xd->cur_frame_force_integer_mv = cm->cur_frame_force_integer_mv;
#endif

  for (int i = 0; i < MAX_SEGMENTS; ++i) {
    const int qindex = cm->seg.enabled
                           ? av1_get_qindex(&cm->seg, i, cm->base_qindex)
                           : cm->base_qindex;
    xd->lossless[i] = qindex == 0 && cm->y_dc_delta_q == 0 &&
                      cm->u_dc_delta_q == 0 && cm->u_ac_delta_q == 0 &&
                      cm->v_dc_delta_q == 0 && cm->v_ac_delta_q == 0;
    xd->qindex[i] = qindex;
  }
  cm->all_lossless = all_lossless(cm, xd);
  setup_segmentation_dequant(cm);
  if (cm->all_lossless) {
    cm->lf.filter_level[0] = 0;
    cm->lf.filter_level[1] = 0;
    cm->cdef_bits = 0;
    cm->cdef_strengths[0] = 0;
    cm->cdef_uv_strengths[0] = 0;
    cm->rst_info[0].frame_restoration_type = RESTORE_NONE;
    cm->rst_info[1].frame_restoration_type = RESTORE_NONE;
    cm->rst_info[2].frame_restoration_type = RESTORE_NONE;
  } else {
    setup_loopfilter(cm, rb);
    setup_cdef(cm, rb);
    decode_restoration_mode(cm, rb);
  }

  cm->tx_mode = read_tx_mode(cm, rb);
  cm->reference_mode = read_frame_reference_mode(cm, rb);
  if (cm->reference_mode != SINGLE_REFERENCE) setup_compound_reference_mode(cm);

  av1_setup_skip_mode_allowed(cm);
  assert(cm->error_resilient_mode ? !cm->is_skip_mode_allowed : 1);
  cm->skip_mode_flag = cm->is_skip_mode_allowed ? aom_rb_read_bit(rb) : 0;

  read_compound_tools(cm, rb);

  cm->reduced_tx_set_used = aom_rb_read_bit(rb);

  if (cm->use_prev_frame_mvs && !frame_can_use_prev_frame_mvs(cm)) {
    aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                       "Frame wrongly requests previous frame MVs");
  }

  if (!frame_is_intra_only(cm)) read_global_motion(cm, rb);

#if CONFIG_FILM_GRAIN_SHOWEX
  cm->showable_frame = 0;
  if (!cm->show_frame) {
    // See if this frame can be used as show_existing_frame in future
    cm->showable_frame = aom_rb_read_bit(rb);
  }
  cm->cur_frame->showable_frame = cm->showable_frame;
#endif
#if CONFIG_FILM_GRAIN
  cm->cur_frame->film_grain_params_present = cm->film_grain_params_present;
#if CONFIG_FILM_GRAIN_SHOWEX
  if (cm->show_frame || cm->showable_frame) {
    read_film_grain(cm, rb);
  }
#else
  if (cm->show_frame) {
    read_film_grain(cm, rb);
  }
#endif
#endif

#if !CONFIG_TILE_INFO_FIRST
  read_tile_info(pbi, rb);
#endif

  return 0;
}

#ifdef NDEBUG
#define debug_check_frame_counts(cm) (void)0
#else   // !NDEBUG
static void debug_check_frame_counts(const AV1_COMMON *const cm) {
  FRAME_COUNTS zero_counts;
  av1_zero(zero_counts);
  assert(cm->refresh_frame_context != REFRESH_FRAME_CONTEXT_BACKWARD ||
         cm->error_resilient_mode);
  assert(!memcmp(cm->counts.partition, zero_counts.partition,
                 sizeof(cm->counts.partition)));
  assert(!memcmp(cm->counts.switchable_interp, zero_counts.switchable_interp,
                 sizeof(cm->counts.switchable_interp)));
  assert(!memcmp(cm->counts.inter_compound_mode,
                 zero_counts.inter_compound_mode,
                 sizeof(cm->counts.inter_compound_mode)));
  assert(!memcmp(cm->counts.interintra, zero_counts.interintra,
                 sizeof(cm->counts.interintra)));
  assert(!memcmp(cm->counts.wedge_interintra, zero_counts.wedge_interintra,
                 sizeof(cm->counts.wedge_interintra)));
  assert(!memcmp(cm->counts.compound_interinter,
                 zero_counts.compound_interinter,
                 sizeof(cm->counts.compound_interinter)));
  assert(!memcmp(cm->counts.motion_mode, zero_counts.motion_mode,
                 sizeof(cm->counts.motion_mode)));
  assert(!memcmp(cm->counts.intra_inter, zero_counts.intra_inter,
                 sizeof(cm->counts.intra_inter)));
  assert(!memcmp(cm->counts.skip, zero_counts.skip, sizeof(cm->counts.skip)));
}
#endif  // NDEBUG

struct aom_read_bit_buffer *av1_init_read_bit_buffer(
    AV1Decoder *pbi, struct aom_read_bit_buffer *rb, const uint8_t *data,
    const uint8_t *data_end) {
  rb->bit_offset = 0;
  rb->error_handler = error_handler;
  rb->error_handler_data = &pbi->common;
  rb->bit_buffer = data;
  rb->bit_buffer_end = data_end;
  return rb;
}

void av1_read_frame_size(struct aom_read_bit_buffer *rb, int num_bits_width,
                         int num_bits_height, int *width, int *height) {
  *width = aom_rb_read_literal(rb, num_bits_width) + 1;
  *height = aom_rb_read_literal(rb, num_bits_height) + 1;
}

BITSTREAM_PROFILE av1_read_profile(struct aom_read_bit_buffer *rb) {
  int profile = aom_rb_read_literal(rb, 2);
  return (BITSTREAM_PROFILE)profile;
}

static void make_update_tile_list_dec(AV1Decoder *pbi, int start_tile,
                                      int num_tile, FRAME_CONTEXT *ec_ctxs[]) {
  for (int i = start_tile; i < start_tile + num_tile; ++i)
    ec_ctxs[i - start_tile] = &pbi->tile_data[i].tctx;
}

void superres_post_decode(AV1Decoder *pbi) {
  AV1_COMMON *const cm = &pbi->common;
  BufferPool *const pool = cm->buffer_pool;

  if (av1_superres_unscaled(cm)) return;

  lock_buffer_pool(pool);
  av1_superres_upscale(cm, pool);
  unlock_buffer_pool(pool);
}

static void dec_setup_frame_boundary_info(AV1_COMMON *const cm) {
// Note: When LOOPFILTERING_ACROSS_TILES is enabled, we need to clear the
// boundary information every frame, since the tile boundaries may
// change every frame (particularly when dependent-horztiles is also
// enabled); when it is disabled, the only information stored is the frame
// boundaries, which only depend on the frame size.
#if !CONFIG_LOOPFILTERING_ACROSS_TILES && !CONFIG_LOOPFILTERING_ACROSS_TILES_EXT
  if (cm->width != cm->last_width || cm->height != cm->last_height)
#endif  // CONFIG_LOOPFILTERING_ACROSS_TILES
  {
    int row, col;
    for (row = 0; row < cm->mi_rows; ++row) {
      BOUNDARY_TYPE *bi = cm->boundary_info + row * cm->mi_stride;
      for (col = 0; col < cm->mi_cols; ++col) {
        *bi = 0;
        bi++;
      }
    }
    av1_setup_frame_boundary_info(cm);
  }
}

int av1_decode_frame_headers_and_setup(AV1Decoder *pbi, const uint8_t *data,
                                       const uint8_t *data_end,
                                       const uint8_t **p_data_end) {
  AV1_COMMON *const cm = &pbi->common;
  const int num_planes = av1_num_planes(cm);
  MACROBLOCKD *const xd = &pbi->mb;

#if CONFIG_BITSTREAM_DEBUG
  bitstream_queue_set_frame_read(cm->current_video_frame * 2 + cm->show_frame);
#endif
#if CONFIG_MISMATCH_DEBUG
  mismatch_move_frame_idx_r();
#endif

  for (int i = LAST_FRAME; i <= ALTREF_FRAME; ++i) {
    cm->global_motion[i] = default_warp_params;
    cm->cur_frame->global_motion[i] = default_warp_params;
  }
  xd->global_motion = cm->global_motion;

  struct aom_read_bit_buffer rb;
  read_uncompressed_header(pbi,
                           av1_init_read_bit_buffer(pbi, &rb, data, data_end));

  // If cm->single_tile_decoding = 0, the independent decoding of a single tile
  // or a section of a frame is not allowed.
  if (!cm->single_tile_decoding &&
      (pbi->dec_tile_row >= 0 || pbi->dec_tile_col >= 0)) {
    pbi->dec_tile_row = -1;
    pbi->dec_tile_col = -1;
  }

  pbi->uncomp_hdr_size = aom_rb_bytes_read(&rb);
  YV12_BUFFER_CONFIG *new_fb = get_frame_new_buffer(cm);
  xd->cur_buf = new_fb;
  if (frame_is_intra_only(cm) && av1_allow_intrabc(cm)) {
    av1_setup_scale_factors_for_frame(
        &cm->sf_identity, xd->cur_buf->y_crop_width, xd->cur_buf->y_crop_height,
        xd->cur_buf->y_crop_width, xd->cur_buf->y_crop_height);
  }

  if (cm->show_existing_frame) {
    // showing a frame directly
    *p_data_end = data + aom_rb_bytes_read(&rb);
#if CONFIG_FWD_KF
    if (cm->reset_decoder_state) {
#if CONFIG_NO_FRAME_CONTEXT_SIGNALING
      // Use the default frame context values.
      *cm->fc = cm->frame_contexts[FRAME_CONTEXT_DEFAULTS];
      cm->pre_fc = &cm->frame_contexts[FRAME_CONTEXT_DEFAULTS];
#else
      // NOTE: cm->frame_context_idx has been set to zero in
      //       av1_setup_past_independence().
      assert(cm->frame_context_idx == 0);
      *cm->fc = cm->frame_contexts[cm->frame_context_idx];
      cm->pre_fc = &cm->frame_contexts[cm->frame_context_idx];
#endif  // CONFIG_NO_FRAME_CONTEXT_SIGNALING
      if (!cm->fc->initialized)
        aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                           "Uninitialized entropy context.");
    }
#endif  // CONFIG_FWD_KF
    return 0;
  }

  cm->setup_mi(cm);

#if CONFIG_SEGMENT_PRED_LAST
  cm->current_frame_seg_map = cm->cur_frame->seg_map;
#endif

  av1_setup_motion_field(cm);

  av1_setup_block_planes(xd, cm->subsampling_x, cm->subsampling_y, num_planes);
#if CONFIG_NO_FRAME_CONTEXT_SIGNALING
  if (cm->primary_ref_frame == PRIMARY_REF_NONE) {
    // use the default frame context values
    *cm->fc = cm->frame_contexts[FRAME_CONTEXT_DEFAULTS];
    cm->pre_fc = &cm->frame_contexts[FRAME_CONTEXT_DEFAULTS];
  } else {
    *cm->fc = cm->frame_contexts[cm->frame_refs[cm->primary_ref_frame].idx];
    cm->pre_fc = &cm->frame_contexts[cm->frame_refs[cm->primary_ref_frame].idx];
  }
#else
  *cm->fc = cm->frame_contexts[cm->frame_context_idx];
  cm->pre_fc = &cm->frame_contexts[cm->frame_context_idx];
#endif  // CONFIG_NO_FRAME_CONTEXT_SIGNALING
  if (!cm->fc->initialized)
    aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                       "Uninitialized entropy context.");

  av1_zero(cm->counts);

  xd->corrupted = 0;
  return 0;
}

// Once-per-frame initialization
static void setup_frame_info(AV1Decoder *pbi) {
  AV1_COMMON *const cm = &pbi->common;

  if (cm->rst_info[0].frame_restoration_type != RESTORE_NONE ||
      cm->rst_info[1].frame_restoration_type != RESTORE_NONE ||
      cm->rst_info[2].frame_restoration_type != RESTORE_NONE) {
    av1_alloc_restoration_buffers(cm);
  }
  dec_setup_frame_boundary_info(cm);
}

void av1_decode_tg_tiles_and_wrapup(AV1Decoder *pbi, const uint8_t *data,
                                    const uint8_t *data_end,
                                    const uint8_t **p_data_end, int startTile,
                                    int endTile, int initialize_flag) {
  AV1_COMMON *const cm = &pbi->common;
  MACROBLOCKD *const xd = &pbi->mb;

  if (initialize_flag) setup_frame_info(pbi);

  *p_data_end = decode_tiles(pbi, data, data_end, startTile, endTile);

  const int num_planes = av1_num_planes(cm);
  // If the bit stream is monochrome, set the U and V buffers to a constant.
  if (num_planes < 3) {
    YV12_BUFFER_CONFIG *cur_buf = (YV12_BUFFER_CONFIG *)xd->cur_buf;
    const int val = 1 << (cm->bit_depth - 1);

    for (int buf_idx = 1; buf_idx <= 2; buf_idx++) {
      for (int row_idx = 0; row_idx < cur_buf->crop_heights[1]; row_idx++) {
        if (cm->use_highbitdepth) {
          // TODO(yaowu): replace this with aom_memset16() for speed
          for (int col_idx = 0; col_idx < cur_buf->crop_widths[1]; col_idx++) {
            uint16_t *base = CONVERT_TO_SHORTPTR(cur_buf->buffers[buf_idx]);
            base[row_idx * cur_buf->uv_stride + col_idx] = val;
          }
        } else {
          memset(&cur_buf->buffers[buf_idx][row_idx * cur_buf->uv_stride],
                 1 << 7, cur_buf->crop_widths[1]);
        }
      }
    }
  }

  if (endTile != cm->tile_rows * cm->tile_cols - 1) {
    return;
  }

  if (!(cm->allow_intrabc && NO_FILTER_FOR_IBC)) {
    if (cm->rst_info[0].frame_restoration_type != RESTORE_NONE ||
        cm->rst_info[1].frame_restoration_type != RESTORE_NONE ||
        cm->rst_info[2].frame_restoration_type != RESTORE_NONE) {
      av1_loop_restoration_save_boundary_lines(&pbi->cur_buf->buf, cm, 0);
    }

    if (!cm->skip_loop_filter && !cm->all_lossless &&
        (cm->cdef_bits || cm->cdef_strengths[0] || cm->cdef_uv_strengths[0])) {
      av1_cdef_frame(&pbi->cur_buf->buf, cm, &pbi->mb);
    }

    superres_post_decode(pbi);

    if (cm->rst_info[0].frame_restoration_type != RESTORE_NONE ||
        cm->rst_info[1].frame_restoration_type != RESTORE_NONE ||
        cm->rst_info[2].frame_restoration_type != RESTORE_NONE) {
      av1_loop_restoration_save_boundary_lines(&pbi->cur_buf->buf, cm, 1);
      av1_loop_restoration_filter_frame((YV12_BUFFER_CONFIG *)xd->cur_buf, cm);
    }
  }

  if (!xd->corrupted) {
    if (cm->refresh_frame_context == REFRESH_FRAME_CONTEXT_BACKWARD) {
      const int num_bwd_ctxs = 1;
      FRAME_CONTEXT **tile_ctxs =
          aom_malloc(num_bwd_ctxs * sizeof(&pbi->tile_data[0].tctx));
      aom_cdf_prob **cdf_ptrs = aom_malloc(
          num_bwd_ctxs * sizeof(&pbi->tile_data[0].tctx.partition_cdf[0][0]));
      make_update_tile_list_dec(pbi, cm->largest_tile_id, num_bwd_ctxs,
                                tile_ctxs);
      av1_average_tile_coef_cdfs(pbi->common.fc, tile_ctxs, cdf_ptrs,
                                 num_bwd_ctxs);
      av1_average_tile_intra_cdfs(pbi->common.fc, tile_ctxs, cdf_ptrs,
                                  num_bwd_ctxs);
      av1_average_tile_loopfilter_cdfs(pbi->common.fc, tile_ctxs, cdf_ptrs,
                                       num_bwd_ctxs);

      if (!frame_is_intra_only(cm)) {
        av1_average_tile_inter_cdfs(&pbi->common, pbi->common.fc, tile_ctxs,
                                    cdf_ptrs, num_bwd_ctxs);
        av1_average_tile_mv_cdfs(pbi->common.fc, tile_ctxs, cdf_ptrs,
                                 num_bwd_ctxs);
      }
      aom_free(tile_ctxs);
      aom_free(cdf_ptrs);
    } else {
      debug_check_frame_counts(cm);
    }
  } else {
    aom_internal_error(&cm->error, AOM_CODEC_CORRUPT_FRAME,
                       "Decode failed. Frame data is corrupted.");
  }

#if CONFIG_INSPECTION
  if (pbi->inspect_cb != NULL) {
    (*pbi->inspect_cb)(pbi, pbi->inspect_ctx);
  }
#endif

  // Non frame parallel update frame context here.
  if (!cm->large_scale_tile) {
#if CONFIG_NO_FRAME_CONTEXT_SIGNALING
    cm->frame_contexts[cm->new_fb_idx] = *cm->fc;
#else
    if (!cm->error_resilient_mode)
      cm->frame_contexts[cm->frame_context_idx] = *cm->fc;
#endif
  }
}