rdopt.c

/*
 * Copyright (c) 2016, Alliance for Open Media. All rights reserved
 *
 * This source code is subject to the terms of the BSD 2 Clause License and
 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
 * was not distributed with this source code in the LICENSE file, you can
 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
 * Media Patent License 1.0 was not distributed with this source code in the
 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
 */

#include <assert.h>
#include <math.h>

#include "./aom_dsp_rtcd.h"
#include "./av1_rtcd.h"

#include "aom_dsp/aom_dsp_common.h"
#include "aom_dsp/blend.h"
#include "aom_mem/aom_mem.h"
#include "aom_ports/mem.h"
#include "aom_ports/system_state.h"

#include "av1/common/common.h"
#include "av1/common/common_data.h"
#include "av1/common/entropy.h"
#include "av1/common/entropymode.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/scan.h"
#include "av1/common/seg_common.h"
#if CONFIG_WARPED_MOTION
#include "av1/common/warped_motion.h"
#endif  // CONFIG_WARPED_MOTION

#include "av1/encoder/aq_variance.h"
#include "av1/encoder/av1_quantize.h"
#include "av1/encoder/cost.h"
#include "av1/encoder/encodemb.h"
#include "av1/encoder/encodemv.h"
#include "av1/encoder/encoder.h"
#include "av1/encoder/hybrid_fwd_txfm.h"
#include "av1/encoder/mcomp.h"
#if CONFIG_PALETTE
#include "av1/encoder/palette.h"
#endif  // CONFIG_PALETTE
#include "av1/encoder/ratectrl.h"
#include "av1/encoder/rd.h"
#include "av1/encoder/rdopt.h"
#include "av1/encoder/tokenize.h"
#if CONFIG_PVQ
#include "av1/encoder/pvq_encoder.h"
#endif  // CONFIG_PVQ
#if CONFIG_PVQ || CONFIG_DAALA_DIST
#include "av1/common/pvq.h"
#endif  // CONFIG_PVQ || CONFIG_DAALA_DIST
#if CONFIG_DUAL_FILTER
#define DUAL_FILTER_SET_SIZE (SWITCHABLE_FILTERS * SWITCHABLE_FILTERS)
static const int filter_sets[DUAL_FILTER_SET_SIZE][2] = {
  { 0, 0 }, { 0, 1 }, { 0, 2 }, { 0, 3 }, { 1, 0 }, { 1, 1 },
  { 1, 2 }, { 1, 3 }, { 2, 0 }, { 2, 1 }, { 2, 2 }, { 2, 3 },
  { 3, 0 }, { 3, 1 }, { 3, 2 }, { 3, 3 },
};
#endif  // CONFIG_DUAL_FILTER

#if CONFIG_EXT_REFS

#define LAST_FRAME_MODE_MASK                                      \
  ((1 << INTRA_FRAME) | (1 << LAST2_FRAME) | (1 << LAST3_FRAME) | \
   (1 << GOLDEN_FRAME) | (1 << BWDREF_FRAME) | (1 << ALTREF_FRAME))
#define LAST2_FRAME_MODE_MASK                                    \
  ((1 << INTRA_FRAME) | (1 << LAST_FRAME) | (1 << LAST3_FRAME) | \
   (1 << GOLDEN_FRAME) | (1 << BWDREF_FRAME) | (1 << ALTREF_FRAME))
#define LAST3_FRAME_MODE_MASK                                    \
  ((1 << INTRA_FRAME) | (1 << LAST_FRAME) | (1 << LAST2_FRAME) | \
   (1 << GOLDEN_FRAME) | (1 << BWDREF_FRAME) | (1 << ALTREF_FRAME))
#define GOLDEN_FRAME_MODE_MASK                                   \
  ((1 << INTRA_FRAME) | (1 << LAST_FRAME) | (1 << LAST2_FRAME) | \
   (1 << LAST3_FRAME) | (1 << BWDREF_FRAME) | (1 << ALTREF_FRAME))
#define BWDREF_FRAME_MODE_MASK                                   \
  ((1 << INTRA_FRAME) | (1 << LAST_FRAME) | (1 << LAST2_FRAME) | \
   (1 << LAST3_FRAME) | (1 << GOLDEN_FRAME) | (1 << ALTREF_FRAME))
#define ALTREF_FRAME_MODE_MASK                                   \
  ((1 << INTRA_FRAME) | (1 << LAST_FRAME) | (1 << LAST2_FRAME) | \
   (1 << LAST3_FRAME) | (1 << GOLDEN_FRAME) | (1 << BWDREF_FRAME))

#else

#define LAST_FRAME_MODE_MASK \
  ((1 << GOLDEN_FRAME) | (1 << ALTREF_FRAME) | (1 << INTRA_FRAME))
#define GOLDEN_FRAME_MODE_MASK \
  ((1 << LAST_FRAME) | (1 << ALTREF_FRAME) | (1 << INTRA_FRAME))
#define ALTREF_FRAME_MODE_MASK \
  ((1 << LAST_FRAME) | (1 << GOLDEN_FRAME) | (1 << INTRA_FRAME))

#endif  // CONFIG_EXT_REFS

#if CONFIG_EXT_REFS
#define SECOND_REF_FRAME_MASK ((1 << ALTREF_FRAME) | (1 << BWDREF_FRAME) | 0x01)
#else
#define SECOND_REF_FRAME_MASK ((1 << ALTREF_FRAME) | 0x01)
#endif  // CONFIG_EXT_REFS

#define MIN_EARLY_TERM_INDEX 3
#define NEW_MV_DISCOUNT_FACTOR 8

#if CONFIG_EXT_INTRA
#define ANGLE_SKIP_THRESH 10
#define FILTER_FAST_SEARCH 1
#endif  // CONFIG_EXT_INTRA

const double ADST_FLIP_SVM[8] = { -6.6623, -2.8062, -3.2531, 3.1671,    // vert
                                  -7.7051, -3.2234, -3.6193, 3.4533 };  // horz

typedef struct {
  PREDICTION_MODE mode;
  MV_REFERENCE_FRAME ref_frame[2];
} MODE_DEFINITION;

typedef struct { MV_REFERENCE_FRAME ref_frame[2]; } REF_DEFINITION;

struct rdcost_block_args {
  const AV1_COMP *cpi;
  MACROBLOCK *x;
  ENTROPY_CONTEXT t_above[2 * MAX_MIB_SIZE];
  ENTROPY_CONTEXT t_left[2 * MAX_MIB_SIZE];
  RD_STATS rd_stats;
  int64_t this_rd;
  int64_t best_rd;
  int exit_early;
  int use_fast_coef_costing;
  const SCAN_ORDER *scan_order;
};

#define LAST_NEW_MV_INDEX 6
static const MODE_DEFINITION av1_mode_order[MAX_MODES] = {
  { NEARESTMV, { LAST_FRAME, NONE_FRAME } },
#if CONFIG_EXT_REFS
  { NEARESTMV, { LAST2_FRAME, NONE_FRAME } },
  { NEARESTMV, { LAST3_FRAME, NONE_FRAME } },
  { NEARESTMV, { BWDREF_FRAME, NONE_FRAME } },
#endif  // CONFIG_EXT_REFS
  { NEARESTMV, { ALTREF_FRAME, NONE_FRAME } },
  { NEARESTMV, { GOLDEN_FRAME, NONE_FRAME } },

  { DC_PRED, { INTRA_FRAME, NONE_FRAME } },

  { NEWMV, { LAST_FRAME, NONE_FRAME } },
#if CONFIG_EXT_REFS
  { NEWMV, { LAST2_FRAME, NONE_FRAME } },
  { NEWMV, { LAST3_FRAME, NONE_FRAME } },
  { NEWMV, { BWDREF_FRAME, NONE_FRAME } },
#endif  // CONFIG_EXT_REFS
  { NEWMV, { ALTREF_FRAME, NONE_FRAME } },
  { NEWMV, { GOLDEN_FRAME, NONE_FRAME } },

  { NEARMV, { LAST_FRAME, NONE_FRAME } },
#if CONFIG_EXT_REFS
  { NEARMV, { LAST2_FRAME, NONE_FRAME } },
  { NEARMV, { LAST3_FRAME, NONE_FRAME } },
  { NEARMV, { BWDREF_FRAME, NONE_FRAME } },
#endif  // CONFIG_EXT_REFS
  { NEARMV, { ALTREF_FRAME, NONE_FRAME } },
  { NEARMV, { GOLDEN_FRAME, NONE_FRAME } },

#if CONFIG_EXT_INTER
  { NEWFROMNEARMV, { LAST_FRAME, NONE_FRAME } },
#if CONFIG_EXT_REFS
  { NEWFROMNEARMV, { LAST2_FRAME, NONE_FRAME } },
  { NEWFROMNEARMV, { LAST3_FRAME, NONE_FRAME } },
  { NEWFROMNEARMV, { BWDREF_FRAME, NONE_FRAME } },
#endif  // CONFIG_EXT_REFS
  { NEWFROMNEARMV, { ALTREF_FRAME, NONE_FRAME } },
  { NEWFROMNEARMV, { GOLDEN_FRAME, NONE_FRAME } },
#endif  // CONFIG_EXT_INTER

  { ZEROMV, { LAST_FRAME, NONE_FRAME } },
#if CONFIG_EXT_REFS
  { ZEROMV, { LAST2_FRAME, NONE_FRAME } },
  { ZEROMV, { LAST3_FRAME, NONE_FRAME } },
  { ZEROMV, { BWDREF_FRAME, NONE_FRAME } },
#endif  // CONFIG_EXT_REFS
  { ZEROMV, { GOLDEN_FRAME, NONE_FRAME } },
  { ZEROMV, { ALTREF_FRAME, NONE_FRAME } },

// TODO(zoeliu): May need to reconsider the order on the modes to check

#if CONFIG_EXT_INTER
  { NEAREST_NEARESTMV, { LAST_FRAME, ALTREF_FRAME } },
#if CONFIG_EXT_REFS
  { NEAREST_NEARESTMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEAREST_NEARESTMV, { LAST3_FRAME, ALTREF_FRAME } },
#endif  // CONFIG_EXT_REFS
  { NEAREST_NEARESTMV, { GOLDEN_FRAME, ALTREF_FRAME } },
#if CONFIG_EXT_REFS
  { NEAREST_NEARESTMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEAREST_NEARESTMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEAREST_NEARESTMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEAREST_NEARESTMV, { GOLDEN_FRAME, BWDREF_FRAME } },
#endif  // CONFIG_EXT_REFS

#else  // CONFIG_EXT_INTER

  { NEARESTMV, { LAST_FRAME, ALTREF_FRAME } },
#if CONFIG_EXT_REFS
  { NEARESTMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEARESTMV, { LAST3_FRAME, ALTREF_FRAME } },
#endif  // CONFIG_EXT_REFS
  { NEARESTMV, { GOLDEN_FRAME, ALTREF_FRAME } },
#if CONFIG_EXT_REFS
  { NEARESTMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEARESTMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEARESTMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEARESTMV, { GOLDEN_FRAME, BWDREF_FRAME } },
#endif  // CONFIG_EXT_REFS
#endif  // CONFIG_EXT_INTER

  { TM_PRED, { INTRA_FRAME, NONE_FRAME } },

#if CONFIG_ALT_INTRA
  { SMOOTH_PRED, { INTRA_FRAME, NONE_FRAME } },
#endif  // CONFIG_ALT_INTRA

#if CONFIG_EXT_INTER
  { NEAR_NEARESTMV, { LAST_FRAME, ALTREF_FRAME } },
  { NEAREST_NEARMV, { LAST_FRAME, ALTREF_FRAME } },
  { NEAR_NEARMV, { LAST_FRAME, ALTREF_FRAME } },
  { NEW_NEARESTMV, { LAST_FRAME, ALTREF_FRAME } },
  { NEAREST_NEWMV, { LAST_FRAME, ALTREF_FRAME } },
  { NEW_NEARMV, { LAST_FRAME, ALTREF_FRAME } },
  { NEAR_NEWMV, { LAST_FRAME, ALTREF_FRAME } },
  { NEW_NEWMV, { LAST_FRAME, ALTREF_FRAME } },
  { ZERO_ZEROMV, { LAST_FRAME, ALTREF_FRAME } },

#if CONFIG_EXT_REFS
  { NEAR_NEARESTMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEAREST_NEARMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEAR_NEARMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEW_NEARESTMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEAREST_NEWMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEW_NEARMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEAR_NEWMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEW_NEWMV, { LAST2_FRAME, ALTREF_FRAME } },
  { ZERO_ZEROMV, { LAST2_FRAME, ALTREF_FRAME } },

  { NEAR_NEARESTMV, { LAST3_FRAME, ALTREF_FRAME } },
  { NEAREST_NEARMV, { LAST3_FRAME, ALTREF_FRAME } },
  { NEAR_NEARMV, { LAST3_FRAME, ALTREF_FRAME } },
  { NEW_NEARESTMV, { LAST3_FRAME, ALTREF_FRAME } },
  { NEAREST_NEWMV, { LAST3_FRAME, ALTREF_FRAME } },
  { NEW_NEARMV, { LAST3_FRAME, ALTREF_FRAME } },
  { NEAR_NEWMV, { LAST3_FRAME, ALTREF_FRAME } },
  { NEW_NEWMV, { LAST3_FRAME, ALTREF_FRAME } },
  { ZERO_ZEROMV, { LAST3_FRAME, ALTREF_FRAME } },
#endif  // CONFIG_EXT_REFS

  { NEAR_NEARESTMV, { GOLDEN_FRAME, ALTREF_FRAME } },
  { NEAREST_NEARMV, { GOLDEN_FRAME, ALTREF_FRAME } },
  { NEAR_NEARMV, { GOLDEN_FRAME, ALTREF_FRAME } },
  { NEW_NEARESTMV, { GOLDEN_FRAME, ALTREF_FRAME } },
  { NEAREST_NEWMV, { GOLDEN_FRAME, ALTREF_FRAME } },
  { NEW_NEARMV, { GOLDEN_FRAME, ALTREF_FRAME } },
  { NEAR_NEWMV, { GOLDEN_FRAME, ALTREF_FRAME } },
  { NEW_NEWMV, { GOLDEN_FRAME, ALTREF_FRAME } },
  { ZERO_ZEROMV, { GOLDEN_FRAME, ALTREF_FRAME } },

#if CONFIG_EXT_REFS
  { NEAR_NEARESTMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEAREST_NEARMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEAR_NEARMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEW_NEARESTMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEAREST_NEWMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEW_NEARMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEAR_NEWMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEW_NEWMV, { LAST_FRAME, BWDREF_FRAME } },
  { ZERO_ZEROMV, { LAST_FRAME, BWDREF_FRAME } },

  { NEAR_NEARESTMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEAREST_NEARMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEAR_NEARMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEW_NEARESTMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEAREST_NEWMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEW_NEARMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEAR_NEWMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEW_NEWMV, { LAST2_FRAME, BWDREF_FRAME } },
  { ZERO_ZEROMV, { LAST2_FRAME, BWDREF_FRAME } },

  { NEAR_NEARESTMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEAREST_NEARMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEAR_NEARMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEW_NEARESTMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEAREST_NEWMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEW_NEARMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEAR_NEWMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEW_NEWMV, { LAST3_FRAME, BWDREF_FRAME } },
  { ZERO_ZEROMV, { LAST3_FRAME, BWDREF_FRAME } },

  { NEAR_NEARESTMV, { GOLDEN_FRAME, BWDREF_FRAME } },
  { NEAREST_NEARMV, { GOLDEN_FRAME, BWDREF_FRAME } },
  { NEAR_NEARMV, { GOLDEN_FRAME, BWDREF_FRAME } },
  { NEW_NEARESTMV, { GOLDEN_FRAME, BWDREF_FRAME } },
  { NEAREST_NEWMV, { GOLDEN_FRAME, BWDREF_FRAME } },
  { NEW_NEARMV, { GOLDEN_FRAME, BWDREF_FRAME } },
  { NEAR_NEWMV, { GOLDEN_FRAME, BWDREF_FRAME } },
  { NEW_NEWMV, { GOLDEN_FRAME, BWDREF_FRAME } },
  { ZERO_ZEROMV, { GOLDEN_FRAME, BWDREF_FRAME } },
#endif  // CONFIG_EXT_REFS

#else  // CONFIG_EXT_INTER

  { NEARMV, { LAST_FRAME, ALTREF_FRAME } },
  { NEWMV, { LAST_FRAME, ALTREF_FRAME } },
#if CONFIG_EXT_REFS
  { NEARMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEWMV, { LAST2_FRAME, ALTREF_FRAME } },
  { NEARMV, { LAST3_FRAME, ALTREF_FRAME } },
  { NEWMV, { LAST3_FRAME, ALTREF_FRAME } },
#endif  // CONFIG_EXT_REFS
  { NEARMV, { GOLDEN_FRAME, ALTREF_FRAME } },
  { NEWMV, { GOLDEN_FRAME, ALTREF_FRAME } },

#if CONFIG_EXT_REFS
  { NEARMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEWMV, { LAST_FRAME, BWDREF_FRAME } },
  { NEARMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEWMV, { LAST2_FRAME, BWDREF_FRAME } },
  { NEARMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEWMV, { LAST3_FRAME, BWDREF_FRAME } },
  { NEARMV, { GOLDEN_FRAME, BWDREF_FRAME } },
  { NEWMV, { GOLDEN_FRAME, BWDREF_FRAME } },
#endif  // CONFIG_EXT_REFS

  { ZEROMV, { LAST_FRAME, ALTREF_FRAME } },
#if CONFIG_EXT_REFS
  { ZEROMV, { LAST2_FRAME, ALTREF_FRAME } },
  { ZEROMV, { LAST3_FRAME, ALTREF_FRAME } },
#endif  // CONFIG_EXT_REFS
  { ZEROMV, { GOLDEN_FRAME, ALTREF_FRAME } },

#if CONFIG_EXT_REFS
  { ZEROMV, { LAST_FRAME, BWDREF_FRAME } },
  { ZEROMV, { LAST2_FRAME, BWDREF_FRAME } },
  { ZEROMV, { LAST3_FRAME, BWDREF_FRAME } },
  { ZEROMV, { GOLDEN_FRAME, BWDREF_FRAME } },
#endif  // CONFIG_EXT_REFS

#endif  // CONFIG_EXT_INTER

  { H_PRED, { INTRA_FRAME, NONE_FRAME } },
  { V_PRED, { INTRA_FRAME, NONE_FRAME } },
  { D135_PRED, { INTRA_FRAME, NONE_FRAME } },
  { D207_PRED, { INTRA_FRAME, NONE_FRAME } },
  { D153_PRED, { INTRA_FRAME, NONE_FRAME } },
  { D63_PRED, { INTRA_FRAME, NONE_FRAME } },
  { D117_PRED, { INTRA_FRAME, NONE_FRAME } },
  { D45_PRED, { INTRA_FRAME, NONE_FRAME } },

#if CONFIG_EXT_INTER
  { ZEROMV, { LAST_FRAME, INTRA_FRAME } },
  { NEARESTMV, { LAST_FRAME, INTRA_FRAME } },
  { NEARMV, { LAST_FRAME, INTRA_FRAME } },
  { NEWMV, { LAST_FRAME, INTRA_FRAME } },

#if CONFIG_EXT_REFS
  { ZEROMV, { LAST2_FRAME, INTRA_FRAME } },
  { NEARESTMV, { LAST2_FRAME, INTRA_FRAME } },
  { NEARMV, { LAST2_FRAME, INTRA_FRAME } },
  { NEWMV, { LAST2_FRAME, INTRA_FRAME } },

  { ZEROMV, { LAST3_FRAME, INTRA_FRAME } },
  { NEARESTMV, { LAST3_FRAME, INTRA_FRAME } },
  { NEARMV, { LAST3_FRAME, INTRA_FRAME } },
  { NEWMV, { LAST3_FRAME, INTRA_FRAME } },
#endif  // CONFIG_EXT_REFS

  { ZEROMV, { GOLDEN_FRAME, INTRA_FRAME } },
  { NEARESTMV, { GOLDEN_FRAME, INTRA_FRAME } },
  { NEARMV, { GOLDEN_FRAME, INTRA_FRAME } },
  { NEWMV, { GOLDEN_FRAME, INTRA_FRAME } },

#if CONFIG_EXT_REFS
  { ZEROMV, { BWDREF_FRAME, INTRA_FRAME } },
  { NEARESTMV, { BWDREF_FRAME, INTRA_FRAME } },
  { NEARMV, { BWDREF_FRAME, INTRA_FRAME } },
  { NEWMV, { BWDREF_FRAME, INTRA_FRAME } },
#endif  // CONFIG_EXT_REFS

  { ZEROMV, { ALTREF_FRAME, INTRA_FRAME } },
  { NEARESTMV, { ALTREF_FRAME, INTRA_FRAME } },
  { NEARMV, { ALTREF_FRAME, INTRA_FRAME } },
  { NEWMV, { ALTREF_FRAME, INTRA_FRAME } },
#endif  // CONFIG_EXT_INTER
};

static const REF_DEFINITION av1_ref_order[MAX_REFS] = {
  { { LAST_FRAME, NONE_FRAME } },
#if CONFIG_EXT_REFS
  { { LAST2_FRAME, NONE_FRAME } },    { { LAST3_FRAME, NONE_FRAME } },
  { { BWDREF_FRAME, NONE_FRAME } },
#endif  // CONFIG_EXT_REFS
  { { GOLDEN_FRAME, NONE_FRAME } },   { { ALTREF_FRAME, NONE_FRAME } },

  { { LAST_FRAME, ALTREF_FRAME } },
#if CONFIG_EXT_REFS
  { { LAST2_FRAME, ALTREF_FRAME } },  { { LAST3_FRAME, ALTREF_FRAME } },
#endif  // CONFIG_EXT_REFS
  { { GOLDEN_FRAME, ALTREF_FRAME } },

#if CONFIG_EXT_REFS
  { { LAST_FRAME, BWDREF_FRAME } },   { { LAST2_FRAME, BWDREF_FRAME } },
  { { LAST3_FRAME, BWDREF_FRAME } },  { { GOLDEN_FRAME, BWDREF_FRAME } },
#endif  // CONFIG_EXT_REFS

  { { INTRA_FRAME, NONE_FRAME } },
};

#if CONFIG_EXT_INTRA || CONFIG_FILTER_INTRA || CONFIG_PALETTE
static INLINE int write_uniform_cost(int n, int v) {
  int l = get_unsigned_bits(n), m = (1 << l) - n;
  if (l == 0) return 0;
  if (v < m)
    return (l - 1) * av1_cost_bit(128, 0);
  else
    return l * av1_cost_bit(128, 0);
}
#endif  // CONFIG_EXT_INTRA || CONFIG_FILTER_INTRA || CONFIG_PALETTE

// constants for prune 1 and prune 2 decision boundaries
#define FAST_EXT_TX_CORR_MID 0.0
#define FAST_EXT_TX_EDST_MID 0.1
#define FAST_EXT_TX_CORR_MARGIN 0.5
#define FAST_EXT_TX_EDST_MARGIN 0.3

static const TX_TYPE_1D vtx_tab[TX_TYPES] = {
  DCT_1D,      ADST_1D, DCT_1D,      ADST_1D,
#if CONFIG_EXT_TX
  FLIPADST_1D, DCT_1D,  FLIPADST_1D, ADST_1D, FLIPADST_1D, IDTX_1D,
  DCT_1D,      IDTX_1D, ADST_1D,     IDTX_1D, FLIPADST_1D, IDTX_1D,
#endif  // CONFIG_EXT_TX
};

static const TX_TYPE_1D htx_tab[TX_TYPES] = {
  DCT_1D,  DCT_1D,      ADST_1D,     ADST_1D,
#if CONFIG_EXT_TX
  DCT_1D,  FLIPADST_1D, FLIPADST_1D, FLIPADST_1D, ADST_1D, IDTX_1D,
  IDTX_1D, DCT_1D,      IDTX_1D,     ADST_1D,     IDTX_1D, FLIPADST_1D,
#endif  // CONFIG_EXT_TX
};

#if CONFIG_DAALA_DIST
static int od_compute_var_4x4(od_coeff *x, int stride) {
  int sum;
  int s2;
  int i;
  sum = 0;
  s2 = 0;
  for (i = 0; i < 4; i++) {
    int j;
    for (j = 0; j < 4; j++) {
      int t;

      t = x[i * stride + j];
      sum += t;
      s2 += t * t;
    }
  }
  // TODO(yushin) : Check wheter any changes are required for high bit depth.
  return (s2 - (sum * sum >> 4)) >> 4;
}

/* OD_DIST_LP_MID controls the frequency weighting filter used for computing
   the distortion. For a value X, the filter is [1 X 1]/(X + 2) and
   is applied both horizontally and vertically. For X=5, the filter is
   a good approximation for the OD_QM8_Q4_HVS quantization matrix. */
#define OD_DIST_LP_MID (5)
#define OD_DIST_LP_NORM (OD_DIST_LP_MID + 2)

static double od_compute_dist_8x8(int qm, int use_activity_masking, od_coeff *x,
                                  od_coeff *y, od_coeff *e_lp, int stride) {
  double sum;
  int min_var;
  double mean_var;
  double var_stat;
  double activity;
  double calibration;
  int i;
  int j;
  double vardist;

  vardist = 0;
  OD_ASSERT(qm != OD_FLAT_QM);
  (void)qm;
#if 1
  min_var = INT_MAX;
  mean_var = 0;
  for (i = 0; i < 3; i++) {
    for (j = 0; j < 3; j++) {
      int varx;
      int vary;
      varx = od_compute_var_4x4(x + 2 * i * stride + 2 * j, stride);
      vary = od_compute_var_4x4(y + 2 * i * stride + 2 * j, stride);
      min_var = OD_MINI(min_var, varx);
      mean_var += 1. / (1 + varx);
      /* The cast to (double) is to avoid an overflow before the sqrt.*/
      vardist += varx - 2 * sqrt(varx * (double)vary) + vary;
    }
  }
  /* We use a different variance statistic depending on whether activity
     masking is used, since the harmonic mean appeared slghtly worse with
     masking off. The calibration constant just ensures that we preserve the
     rate compared to activity=1. */
  if (use_activity_masking) {
    calibration = 1.95;
    var_stat = 9. / mean_var;
  } else {
    calibration = 1.62;
    var_stat = min_var;
  }
  /* 1.62 is a calibration constant, 0.25 is a noise floor and 1/6 is the
     activity masking constant. */
  activity = calibration * pow(.25 + var_stat, -1. / 6);
#else
  activity = 1;
#endif  // 1
  sum = 0;
  for (i = 0; i < 8; i++) {
    for (j = 0; j < 8; j++)
      sum += e_lp[i * stride + j] * (double)e_lp[i * stride + j];
  }
  /* Normalize the filter to unit DC response. */
  sum *= 1. / (OD_DIST_LP_NORM * OD_DIST_LP_NORM * OD_DIST_LP_NORM *
               OD_DIST_LP_NORM);
  return activity * activity * (sum + vardist);
}

// Note : Inputs x and y are in a pixel domain
static double od_compute_dist(int qm, int activity_masking, od_coeff *x,
                              od_coeff *y, int bsize_w, int bsize_h,
                              int qindex) {
  int i;
  double sum;
  sum = 0;

  assert(bsize_w >= 8 && bsize_h >= 8);

  if (qm == OD_FLAT_QM) {
    for (i = 0; i < bsize_w * bsize_h; i++) {
      double tmp;
      tmp = x[i] - y[i];
      sum += tmp * tmp;
    }
  } else {
    int j;
    DECLARE_ALIGNED(16, od_coeff, e[MAX_TX_SQUARE]);
    DECLARE_ALIGNED(16, od_coeff, tmp[MAX_TX_SQUARE]);
    DECLARE_ALIGNED(16, od_coeff, e_lp[MAX_TX_SQUARE]);
    int mid = OD_DIST_LP_MID;
    for (i = 0; i < bsize_h; i++) {
      for (j = 0; j < bsize_w; j++) {
        e[i * bsize_w + j] = x[i * bsize_w + j] - y[i * bsize_w + j];
      }
    }
    for (i = 0; i < bsize_h; i++) {
      tmp[i * bsize_w] = mid * e[i * bsize_w] + 2 * e[i * bsize_w + 1];
      tmp[i * bsize_w + bsize_w - 1] =
          mid * e[i * bsize_w + bsize_w - 1] + 2 * e[i * bsize_w + bsize_w - 2];
      for (j = 1; j < bsize_w - 1; j++) {
        tmp[i * bsize_w + j] = mid * e[i * bsize_w + j] +
                               e[i * bsize_w + j - 1] + e[i * bsize_w + j + 1];
      }
    }
    for (j = 0; j < bsize_w; j++) {
      e_lp[j] = mid * tmp[j] + 2 * tmp[bsize_w + j];
      e_lp[(bsize_h - 1) * bsize_w + j] =
          mid * tmp[(bsize_h - 1) * bsize_w + j] +
          2 * tmp[(bsize_h - 2) * bsize_w + j];
    }
    for (i = 1; i < bsize_h - 1; i++) {
      for (j = 0; j < bsize_w; j++) {
        e_lp[i * bsize_w + j] = mid * tmp[i * bsize_w + j] +
                                tmp[(i - 1) * bsize_w + j] +
                                tmp[(i + 1) * bsize_w + j];
      }
    }
    for (i = 0; i < bsize_h; i += 8) {
      for (j = 0; j < bsize_w; j += 8) {
        sum += od_compute_dist_8x8(qm, activity_masking, &x[i * bsize_w + j],
                                   &y[i * bsize_w + j], &e_lp[i * bsize_w + j],
                                   bsize_w);
      }
    }
    /* Scale according to linear regression against SSE, for 8x8 blocks. */
    if (activity_masking) {
      sum *= 2.2 + (1.7 - 2.2) * (qindex - 99) / (210 - 99) +
             (qindex < 99 ? 2.5 * (qindex - 99) / 99 * (qindex - 99) / 99 : 0);
    } else {
      sum *= qindex >= 128
                 ? 1.4 + (0.9 - 1.4) * (qindex - 128) / (209 - 128)
                 : qindex <= 43
                       ? 1.5 + (2.0 - 1.5) * (qindex - 43) / (16 - 43)
                       : 1.5 + (1.4 - 1.5) * (qindex - 43) / (128 - 43);
    }
  }
  return sum;
}

static int64_t av1_daala_dist(const uint8_t *src, int src_stride,
                              const uint8_t *dst, int dst_stride, int tx_size,
                              int qm, int use_activity_masking, int qindex) {
  int i, j;
  int64_t d;
  const BLOCK_SIZE tx_bsize = txsize_to_bsize[tx_size];
  const int bsw = block_size_wide[tx_bsize];
  const int bsh = block_size_high[tx_bsize];
  DECLARE_ALIGNED(16, od_coeff, orig[MAX_TX_SQUARE]);
  DECLARE_ALIGNED(16, od_coeff, rec[MAX_TX_SQUARE]);

  assert(qm == OD_HVS_QM);

  for (j = 0; j < bsh; j++)
    for (i = 0; i < bsw; i++) orig[j * bsw + i] = src[j * src_stride + i];

  for (j = 0; j < bsh; j++)
    for (i = 0; i < bsw; i++) rec[j * bsw + i] = dst[j * dst_stride + i];

  d = (int64_t)od_compute_dist(qm, use_activity_masking, orig, rec, bsw, bsh,
                               qindex);
  return d;
}
#endif  // CONFIG_DAALA_DIST

static void get_energy_distribution_fine(const AV1_COMP *cpi, BLOCK_SIZE bsize,
                                         uint8_t *src, int src_stride,
                                         uint8_t *dst, int dst_stride,
                                         double *hordist, double *verdist) {
  int bw = block_size_wide[bsize];
  int bh = block_size_high[bsize];
  unsigned int esq[16] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
  unsigned int var[16];
  double total = 0;

  const int f_index = bsize - BLOCK_16X16;
  if (f_index < 0) {
    int i, j, index;
    int w_shift = bw == 8 ? 1 : 2;
    int h_shift = bh == 8 ? 1 : 2;
#if CONFIG_AOM_HIGHBITDEPTH
    if (cpi->common.use_highbitdepth) {
      uint16_t *src16 = CONVERT_TO_SHORTPTR(src);
      uint16_t *dst16 = CONVERT_TO_SHORTPTR(dst);
      for (i = 0; i < bh; ++i)
        for (j = 0; j < bw; ++j) {
          index = (j >> w_shift) + ((i >> h_shift) << 2);
          esq[index] +=
              (src16[j + i * src_stride] - dst16[j + i * dst_stride]) *
              (src16[j + i * src_stride] - dst16[j + i * dst_stride]);
        }
    } else {
#endif  // CONFIG_AOM_HIGHBITDEPTH

      for (i = 0; i < bh; ++i)
        for (j = 0; j < bw; ++j) {
          index = (j >> w_shift) + ((i >> h_shift) << 2);
          esq[index] += (src[j + i * src_stride] - dst[j + i * dst_stride]) *
                        (src[j + i * src_stride] - dst[j + i * dst_stride]);
        }
#if CONFIG_AOM_HIGHBITDEPTH
    }
#endif  // CONFIG_AOM_HIGHBITDEPTH
  } else {
    var[0] = cpi->fn_ptr[f_index].vf(src, src_stride, dst, dst_stride, &esq[0]);
    var[1] = cpi->fn_ptr[f_index].vf(src + bw / 4, src_stride, dst + bw / 4,
                                     dst_stride, &esq[1]);
    var[2] = cpi->fn_ptr[f_index].vf(src + bw / 2, src_stride, dst + bw / 2,
                                     dst_stride, &esq[2]);
    var[3] = cpi->fn_ptr[f_index].vf(src + 3 * bw / 4, src_stride,
                                     dst + 3 * bw / 4, dst_stride, &esq[3]);
    src += bh / 4 * src_stride;
    dst += bh / 4 * dst_stride;

    var[4] = cpi->fn_ptr[f_index].vf(src, src_stride, dst, dst_stride, &esq[4]);
    var[5] = cpi->fn_ptr[f_index].vf(src + bw / 4, src_stride, dst + bw / 4,
                                     dst_stride, &esq[5]);
    var[6] = cpi->fn_ptr[f_index].vf(src + bw / 2, src_stride, dst + bw / 2,
                                     dst_stride, &esq[6]);
    var[7] = cpi->fn_ptr[f_index].vf(src + 3 * bw / 4, src_stride,
                                     dst + 3 * bw / 4, dst_stride, &esq[7]);
    src += bh / 4 * src_stride;
    dst += bh / 4 * dst_stride;

    var[8] = cpi->fn_ptr[f_index].vf(src, src_stride, dst, dst_stride, &esq[8]);
    var[9] = cpi->fn_ptr[f_index].vf(src + bw / 4, src_stride, dst + bw / 4,
                                     dst_stride, &esq[9]);
    var[10] = cpi->fn_ptr[f_index].vf(src + bw / 2, src_stride, dst + bw / 2,
                                      dst_stride, &esq[10]);
    var[11] = cpi->fn_ptr[f_index].vf(src + 3 * bw / 4, src_stride,
                                      dst + 3 * bw / 4, dst_stride, &esq[11]);
    src += bh / 4 * src_stride;
    dst += bh / 4 * dst_stride;

    var[12] =
        cpi->fn_ptr[f_index].vf(src, src_stride, dst, dst_stride, &esq[12]);
    var[13] = cpi->fn_ptr[f_index].vf(src + bw / 4, src_stride, dst + bw / 4,
                                      dst_stride, &esq[13]);
    var[14] = cpi->fn_ptr[f_index].vf(src + bw / 2, src_stride, dst + bw / 2,
                                      dst_stride, &esq[14]);
    var[15] = cpi->fn_ptr[f_index].vf(src + 3 * bw / 4, src_stride,
                                      dst + 3 * bw / 4, dst_stride, &esq[15]);
  }

  total = esq[0] + esq[1] + esq[2] + esq[3] + esq[4] + esq[5] + esq[6] +
          esq[7] + esq[8] + esq[9] + esq[10] + esq[11] + esq[12] + esq[13] +
          esq[14] + esq[15];
  if (total > 0) {
    const double e_recip = 1.0 / total;
    hordist[0] =
        ((double)esq[0] + (double)esq[4] + (double)esq[8] + (double)esq[12]) *
        e_recip;
    hordist[1] =
        ((double)esq[1] + (double)esq[5] + (double)esq[9] + (double)esq[13]) *
        e_recip;
    hordist[2] =
        ((double)esq[2] + (double)esq[6] + (double)esq[10] + (double)esq[14]) *
        e_recip;
    verdist[0] =
        ((double)esq[0] + (double)esq[1] + (double)esq[2] + (double)esq[3]) *
        e_recip;
    verdist[1] =
        ((double)esq[4] + (double)esq[5] + (double)esq[6] + (double)esq[7]) *
        e_recip;
    verdist[2] =
        ((double)esq[8] + (double)esq[9] + (double)esq[10] + (double)esq[11]) *
        e_recip;
  } else {
    hordist[0] = verdist[0] = 0.25;
    hordist[1] = verdist[1] = 0.25;
    hordist[2] = verdist[2] = 0.25;
  }
  (void)var[0];
  (void)var[1];
  (void)var[2];
  (void)var[3];
  (void)var[4];
  (void)var[5];
  (void)var[6];
  (void)var[7];
  (void)var[8];
  (void)var[9];
  (void)var[10];
  (void)var[11];
  (void)var[12];
  (void)var[13];
  (void)var[14];
  (void)var[15];
}

static int adst_vs_flipadst(const AV1_COMP *cpi, BLOCK_SIZE bsize, uint8_t *src,
                            int src_stride, uint8_t *dst, int dst_stride,
                            double *hdist, double *vdist) {
  int prune_bitmask = 0;
  double svm_proj_h = 0, svm_proj_v = 0;
  get_energy_distribution_fine(cpi, bsize, src, src_stride, dst, dst_stride,
                               hdist, vdist);

  svm_proj_v = vdist[0] * ADST_FLIP_SVM[0] + vdist[1] * ADST_FLIP_SVM[1] +
               vdist[2] * ADST_FLIP_SVM[2] + ADST_FLIP_SVM[3];
  svm_proj_h = hdist[0] * ADST_FLIP_SVM[4] + hdist[1] * ADST_FLIP_SVM[5] +
               hdist[2] * ADST_FLIP_SVM[6] + ADST_FLIP_SVM[7];
  if (svm_proj_v > FAST_EXT_TX_EDST_MID + FAST_EXT_TX_EDST_MARGIN)
    prune_bitmask |= 1 << FLIPADST_1D;
  else if (svm_proj_v < FAST_EXT_TX_EDST_MID - FAST_EXT_TX_EDST_MARGIN)
    prune_bitmask |= 1 << ADST_1D;

  if (svm_proj_h > FAST_EXT_TX_EDST_MID + FAST_EXT_TX_EDST_MARGIN)
    prune_bitmask |= 1 << (FLIPADST_1D + 8);
  else if (svm_proj_h < FAST_EXT_TX_EDST_MID - FAST_EXT_TX_EDST_MARGIN)
    prune_bitmask |= 1 << (ADST_1D + 8);

  return prune_bitmask;
}

#if CONFIG_EXT_TX
static void get_horver_correlation(int16_t *diff, int stride, int w, int h,
                                   double *hcorr, double *vcorr) {
  // Returns hor/ver correlation coefficient
  const int num = (h - 1) * (w - 1);
  double num_r;
  int i, j;
  int64_t xy_sum = 0, xz_sum = 0;
  int64_t x_sum = 0, y_sum = 0, z_sum = 0;
  int64_t x2_sum = 0, y2_sum = 0, z2_sum = 0;
  double x_var_n, y_var_n, z_var_n, xy_var_n, xz_var_n;
  *hcorr = *vcorr = 1;

  assert(num > 0);
  num_r = 1.0 / num;
  for (i = 1; i < h; ++i) {
    for (j = 1; j < w; ++j) {
      const int16_t x = diff[i * stride + j];
      const int16_t y = diff[i * stride + j - 1];
      const int16_t z = diff[(i - 1) * stride + j];
      xy_sum += x * y;
      xz_sum += x * z;
      x_sum += x;
      y_sum += y;
      z_sum += z;
      x2_sum += x * x;
      y2_sum += y * y;
      z2_sum += z * z;
    }
  }
  x_var_n = x2_sum - (x_sum * x_sum) * num_r;
  y_var_n = y2_sum - (y_sum * y_sum) * num_r;
  z_var_n = z2_sum - (z_sum * z_sum) * num_r;
  xy_var_n = xy_sum - (x_sum * y_sum) * num_r;
  xz_var_n = xz_sum - (x_sum * z_sum) * num_r;
  if (x_var_n > 0 && y_var_n > 0) {
    *hcorr = xy_var_n / sqrt(x_var_n * y_var_n);
    *hcorr = *hcorr < 0 ? 0 : *hcorr;
  }
  if (x_var_n > 0 && z_var_n > 0) {
    *vcorr = xz_var_n / sqrt(x_var_n * z_var_n);
    *vcorr = *vcorr < 0 ? 0 : *vcorr;
  }
}

int dct_vs_idtx(int16_t *diff, int stride, int w, int h, double *hcorr,
                double *vcorr) {
  int prune_bitmask = 0;
  get_horver_correlation(diff, stride, w, h, hcorr, vcorr);

  if (*vcorr > FAST_EXT_TX_CORR_MID + FAST_EXT_TX_CORR_MARGIN)
    prune_bitmask |= 1 << IDTX_1D;
  else if (*vcorr < FAST_EXT_TX_CORR_MID - FAST_EXT_TX_CORR_MARGIN)
    prune_bitmask |= 1 << DCT_1D;

  if (*hcorr > FAST_EXT_TX_CORR_MID + FAST_EXT_TX_CORR_MARGIN)
    prune_bitmask |= 1 << (IDTX_1D + 8);
  else if (*hcorr < FAST_EXT_TX_CORR_MID - FAST_EXT_TX_CORR_MARGIN)
    prune_bitmask |= 1 << (DCT_1D + 8);
  return prune_bitmask;
}

// Performance drop: 0.5%, Speed improvement: 24%
static int prune_two_for_sby(const AV1_COMP *cpi, BLOCK_SIZE bsize,
                             MACROBLOCK *x, MACROBLOCKD *xd, int adst_flipadst,
                             int dct_idtx) {
  struct macroblock_plane *const p = &x->plane[0];
  struct macroblockd_plane *const pd = &xd->plane[0];
  const BLOCK_SIZE bs = get_plane_block_size(bsize, pd);
  const int bw = 4 << (b_width_log2_lookup[bs]);
  const int bh = 4 << (b_height_log2_lookup[bs]);
  double hdist[3] = { 0, 0, 0 }, vdist[3] = { 0, 0, 0 };
  double hcorr, vcorr;
  int prune = 0;
  av1_subtract_plane(x, bsize, 0);

  if (adst_flipadst)
    prune |= adst_vs_flipadst(cpi, bsize, p->src.buf, p->src.stride,
                              pd->dst.buf, pd->dst.stride, hdist, vdist);
  if (dct_idtx) prune |= dct_vs_idtx(p->src_diff, bw, bw, bh, &hcorr, &vcorr);

  return prune;
}
#endif  // CONFIG_EXT_TX

// Performance drop: 0.3%, Speed improvement: 5%
static int prune_one_for_sby(const AV1_COMP *cpi, BLOCK_SIZE bsize,
                             MACROBLOCK *x, MACROBLOCKD *xd) {
  struct macroblock_plane *const p = &x->plane[0];
  struct macroblockd_plane *const pd = &xd->plane[0];
  double hdist[3] = { 0, 0, 0 }, vdist[3] = { 0, 0, 0 };
  av1_subtract_plane(x, bsize, 0);
  return adst_vs_flipadst(cpi, bsize, p->src.buf, p->src.stride, pd->dst.buf,
                          pd->dst.stride, hdist, vdist);
}

static int prune_tx_types(const AV1_COMP *cpi, BLOCK_SIZE bsize, MACROBLOCK *x,
                          MACROBLOCKD *xd, int tx_set) {
#if CONFIG_EXT_TX
  const int *tx_set_1D = ext_tx_used_inter_1D[tx_set];
#else
  const int tx_set_1D[TX_TYPES_1D] = { 0 };
#endif  // CONFIG_EXT_TX

  switch (cpi->sf.tx_type_search.prune_mode) {
    case NO_PRUNE: return 0; break;
    case PRUNE_ONE:
      if ((tx_set >= 0) && !(tx_set_1D[FLIPADST_1D] & tx_set_1D[ADST_1D]))
        return 0;
      return prune_one_for_sby(cpi, bsize, x, xd);
      break;
#if CONFIG_EXT_TX
    case PRUNE_TWO:
      if ((tx_set >= 0) && !(tx_set_1D[FLIPADST_1D] & tx_set_1D[ADST_1D])) {
        if (!(tx_set_1D[DCT_1D] & tx_set_1D[IDTX_1D])) return 0;
        return prune_two_for_sby(cpi, bsize, x, xd, 0, 1);
      }
      if ((tx_set >= 0) && !(tx_set_1D[DCT_1D] & tx_set_1D[IDTX_1D]))
        return prune_two_for_sby(cpi, bsize, x, xd, 1, 0);
      return prune_two_for_sby(cpi, bsize, x, xd, 1, 1);
      break;
#endif  // CONFIG_EXT_TX
  }
  assert(0);
  return 0;
}

static int do_tx_type_search(TX_TYPE tx_type, int prune) {
// TODO(sarahparker) implement for non ext tx
#if CONFIG_EXT_TX
  return !(((prune >> vtx_tab[tx_type]) & 1) |
           ((prune >> (htx_tab[tx_type] + 8)) & 1));
#else
  // temporary to avoid compiler warnings
  (void)vtx_tab;
  (void)htx_tab;
  (void)tx_type;
  (void)prune;
  return 1;
#endif  // CONFIG_EXT_TX
}

static void model_rd_from_sse(const AV1_COMP *const cpi,
                              const MACROBLOCKD *const xd, BLOCK_SIZE bsize,
                              int plane, int64_t sse, int *rate,
                              int64_t *dist) {
  const struct macroblockd_plane *const pd = &xd->plane[plane];
  const int dequant_shift =
#if CONFIG_AOM_HIGHBITDEPTH
      (xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH) ? xd->bd - 5 :
#endif  // CONFIG_AOM_HIGHBITDEPTH
                                                    3;

  // Fast approximate the modelling function.
  if (cpi->sf.simple_model_rd_from_var) {
    const int64_t square_error = sse;
    int quantizer = (pd->dequant[1] >> dequant_shift);

    if (quantizer < 120)
      *rate = (int)((square_error * (280 - quantizer)) >>
                    (16 - AV1_PROB_COST_SHIFT));
    else
      *rate = 0;
    *dist = (square_error * quantizer) >> 8;
  } else {
    av1_model_rd_from_var_lapndz(sse, num_pels_log2_lookup[bsize],
                                 pd->dequant[1] >> dequant_shift, rate, dist);
  }

  *dist <<= 4;
}

static void model_rd_for_sb(const AV1_COMP *const cpi, BLOCK_SIZE bsize,
                            MACROBLOCK *x, MACROBLOCKD *xd, int plane_from,
                            int plane_to, int *out_rate_sum,
                            int64_t *out_dist_sum, int *skip_txfm_sb,
                            int64_t *skip_sse_sb) {
  // Note our transform coeffs are 8 times an orthogonal transform.
  // Hence quantizer step is also 8 times. To get effective quantizer
  // we need to divide by 8 before sending to modeling function.
  int plane;
  const int ref = xd->mi[0]->mbmi.ref_frame[0];

  int64_t rate_sum = 0;
  int64_t dist_sum = 0;
  int64_t total_sse = 0;

  x->pred_sse[ref] = 0;

  for (plane = plane_from; plane <= plane_to; ++plane) {
    struct macroblock_plane *const p = &x->plane[plane];
    struct macroblockd_plane *const pd = &xd->plane[plane];
#if CONFIG_CB4X4 && !CONFIG_CHROMA_2X2
    const BLOCK_SIZE bs = AOMMAX(BLOCK_4X4, get_plane_block_size(bsize, pd));
#else
    const BLOCK_SIZE bs = get_plane_block_size(bsize, pd);
#endif  // CONFIG_CB4X4 && !CONFIG_CHROMA_2X2

    unsigned int sse;
    int rate;
    int64_t dist;

#if CONFIG_CB4X4
    if (x->skip_chroma_rd && plane) continue;
#endif  // CONFIG_CB4X4

    // TODO(geza): Write direct sse functions that do not compute
    // variance as well.
    cpi->fn_ptr[bs].vf(p->src.buf, p->src.stride, pd->dst.buf, pd->dst.stride,
                       &sse);

    if (plane == 0) x->pred_sse[ref] = sse;

    total_sse += sse;

    model_rd_from_sse(cpi, xd, bs, plane, sse, &rate, &dist);

    rate_sum += rate;
    dist_sum += dist;
  }

  *skip_txfm_sb = total_sse == 0;
  *skip_sse_sb = total_sse << 4;
  *out_rate_sum = (int)rate_sum;
  *out_dist_sum = dist_sum;
}

#if CONFIG_PVQ
// Without PVQ, av1_block_error_c() return two kind of errors,
// 1) reconstruction (i.e. decoded) error and
// 2) Squared sum of transformed residue (i.e. 'coeff')
// However, if PVQ is enabled, coeff does not keep the transformed residue
// but instead a transformed original is kept.
// Hence, new parameter ref vector (i.e. transformed predicted signal)
// is required to derive the residue signal,
// i.e. coeff - ref = residue (all transformed).

// TODO(yushin) : Since 4x4 case does not need ssz, better to refactor into
// a separate function that does not do the extra computations for ssz.
static int64_t av1_block_error2_c(const tran_low_t *coeff,
                                  const tran_low_t *dqcoeff,
                                  const tran_low_t *ref, intptr_t block_size,
                                  int64_t *ssz) {
  int64_t error;

  // Use the existing sse codes for calculating distortion of decoded signal:
  // i.e. (orig - decoded)^2
  error = av1_block_error_fp(coeff, dqcoeff, block_size);
  // prediction residue^2 = (orig - ref)^2
  *ssz = av1_block_error_fp(coeff, ref, block_size);

  return error;
}
#endif  // CONFIG_PVQ

int64_t av1_block_error_c(const tran_low_t *coeff, const tran_low_t *dqcoeff,
                          intptr_t block_size, int64_t *ssz) {
  int i;
  int64_t error = 0, sqcoeff = 0;

  for (i = 0; i < block_size; i++) {
    const int diff = coeff[i] - dqcoeff[i];
    error += diff * diff;
    sqcoeff += coeff[i] * coeff[i];
  }

  *ssz = sqcoeff;
  return error;
}

int64_t av1_block_error_fp_c(const int16_t *coeff, const int16_t *dqcoeff,
                             int block_size) {
  int i;
  int64_t error = 0;

  for (i = 0; i < block_size; i++) {
    const int diff = coeff[i] - dqcoeff[i];
    error += diff * diff;
  }

  return error;
}

#if CONFIG_AOM_HIGHBITDEPTH
int64_t av1_highbd_block_error_c(const tran_low_t *coeff,
                                 const tran_low_t *dqcoeff, intptr_t block_size,
                                 int64_t *ssz, int bd) {
  int i;
  int64_t error = 0, sqcoeff = 0;
  int shift = 2 * (bd - 8);
  int rounding = shift > 0 ? 1 << (shift - 1) : 0;

  for (i = 0; i < block_size; i++) {
    const int64_t diff = coeff[i] - dqcoeff[i];
    error += diff * diff;
    sqcoeff += (int64_t)coeff[i] * (int64_t)coeff[i];
  }
  assert(error >= 0 && sqcoeff >= 0);
  error = (error + rounding) >> shift;
  sqcoeff = (sqcoeff + rounding) >> shift;

  *ssz = sqcoeff;
  return error;
}
#endif  // CONFIG_AOM_HIGHBITDEPTH

#if !CONFIG_PVQ || CONFIG_VAR_TX
/* The trailing '0' is a terminator which is used inside av1_cost_coeffs() to
 * decide whether to include cost of a trailing EOB node or not (i.e. we
 * can skip this if the last coefficient in this transform block, e.g. the
 * 16th coefficient in a 4x4 block or the 64th coefficient in a 8x8 block,
 * were non-zero). */