/*

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

 *

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

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

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

 *  in the file PATENTS.  All contributing project authors may

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

 */

#include <assert.h>

#include <limits.h>

#include "vpx_config.h"

#include "./vpx_dsp_rtcd.h"

#include "onyx_int.h"

#include "modecosts.h"

#include "encodeintra.h"

#include "vp8/common/common.h"

#include "vp8/common/entropymode.h"

#include "pickinter.h"

#include "vp8/common/findnearmv.h"

#include "encodemb.h"

#include "vp8/common/reconinter.h"

#include "vp8/common/reconintra.h"

#include "vp8/common/reconintra4x4.h"

#include "vpx_dsp/variance.h"

#include "mcomp.h"

#include "vp8/common/vp8_skin_detection.h"

#include "rdopt.h"

#include "vpx_dsp/vpx_dsp_common.h"

#include "vpx_mem/vpx_mem.h"

#if CONFIG_TEMPORAL_DENOISING

#include "denoising.h"

#endif

#ifdef SPEEDSTATS

extern unsigned int cnt_pm;

#endif

extern const int vp8_ref_frame_order[MAX_MODES];

extern const MB_PREDICTION_MODE vp8_mode_order[MAX_MODES];

static int macroblock_corner_grad(unsigned char *signal, int stride,

                                  int offsetx, int offsety, int sgnx,

                                  int sgny) {

  int y1 = signal[offsetx * stride + offsety];

  int y2 = signal[offsetx * stride + offsety + sgny];

  int y3 = signal[(offsetx + sgnx) * stride + offsety];

  int y4 = signal[(offsetx + sgnx) * stride + offsety + sgny];

  return VPXMAX(VPXMAX(abs(y1 - y2), abs(y1 - y3)), abs(y1 - y4));

}

static int check_dot_artifact_candidate(VP8_COMP *cpi, MACROBLOCK *x,

                                        unsigned char *target_last, int stride,

                                        unsigned char *last_ref, int mb_row,

                                        int mb_col, int channel) {

  int threshold1 = 6;

  int threshold2 = 3;

  unsigned int max_num = (cpi->common.MBs) / 10;

  int grad_last = 0;

  int grad_source = 0;

  int index = mb_row * cpi->common.mb_cols + mb_col;

  // Threshold for #consecutive (base layer) frames using zero_last mode.

  int num_frames = 30;

  int shift = 15;

  if (channel > 0) {

    shift = 7;

  }

  if (cpi->oxcf.number_of_layers > 1) {

    num_frames = 20;

  }

  x->zero_last_dot_suppress = 0;

  // Blocks on base layer frames that have been using ZEROMV_LAST repeatedly

  // (i.e, at least |x| consecutive frames are candidates for increasing the

  // rd adjustment for zero_last mode.

  // Only allow this for at most |max_num| blocks per frame.

  // Don't allow this for screen content input.

  if (cpi->current_layer == 0 &&

      cpi->consec_zero_last_mvbias[index] > num_frames &&

      x->mbs_zero_last_dot_suppress < max_num &&

      !cpi->oxcf.screen_content_mode) {

    // If this block is checked here, label it so we don't check it again until

    // ~|x| framaes later.

    x->zero_last_dot_suppress = 1;

    // Dot artifact is noticeable as strong gradient at corners of macroblock,

    // for flat areas. As a simple detector for now, we look for a high

    // corner gradient on last ref, and a smaller gradient on source.

    // Check 4 corners, return if any satisfy condition.

    // Top-left:

    grad_last = macroblock_corner_grad(last_ref, stride, 0, 0, 1, 1);

    grad_source = macroblock_corner_grad(target_last, stride, 0, 0, 1, 1);

    if (grad_last >= threshold1 && grad_source <= threshold2) {

      x->mbs_zero_last_dot_suppress++;

      return 1;

    }

    // Top-right:

    grad_last = macroblock_corner_grad(last_ref, stride, 0, shift, 1, -1);

    grad_source = macroblock_corner_grad(target_last, stride, 0, shift, 1, -1);

    if (grad_last >= threshold1 && grad_source <= threshold2) {

      x->mbs_zero_last_dot_suppress++;

      return 1;

    }

    // Bottom-left:

    grad_last = macroblock_corner_grad(last_ref, stride, shift, 0, -1, 1);

    grad_source = macroblock_corner_grad(target_last, stride, shift, 0, -1, 1);

    if (grad_last >= threshold1 && grad_source <= threshold2) {

      x->mbs_zero_last_dot_suppress++;

      return 1;

    }

    // Bottom-right:

    grad_last = macroblock_corner_grad(last_ref, stride, shift, shift, -1, -1);

    grad_source =

        macroblock_corner_grad(target_last, stride, shift, shift, -1, -1);

    if (grad_last >= threshold1 && grad_source <= threshold2) {

      x->mbs_zero_last_dot_suppress++;

      return 1;

    }

    return 0;

  }

  return 0;

}

int vp8_skip_fractional_mv_step(MACROBLOCK *mb, BLOCK *b, BLOCKD *d,

                                int_mv *bestmv, int_mv *ref_mv,

                                int error_per_bit,

                                const vp8_variance_fn_ptr_t *vfp,

                                int *mvcost[2], int *distortion,

                                unsigned int *sse) {

  (void)b;

  (void)d;

  (void)ref_mv;

  (void)error_per_bit;

  (void)vfp;

  (void)mb;

  (void)mvcost;

  (void)distortion;

  (void)sse;

  bestmv->as_mv.row *= 8;

  bestmv->as_mv.col *= 8;

  return 0;

}

int vp8_get_inter_mbpred_error(MACROBLOCK *mb, const vp8_variance_fn_ptr_t *vfp,

                               unsigned int *sse, int_mv this_mv) {

  BLOCK *b = &mb->block[0];

  BLOCKD *d = &mb->e_mbd.block[0];

  unsigned char *what = (*(b->base_src) + b->src);

  int what_stride = b->src_stride;

  int pre_stride = mb->e_mbd.pre.y_stride;

  unsigned char *in_what = mb->e_mbd.pre.y_buffer + d->offset;

  int in_what_stride = pre_stride;

  int xoffset = this_mv.as_mv.col & 7;

  int yoffset = this_mv.as_mv.row & 7;

  in_what += (this_mv.as_mv.row >> 3) * pre_stride + (this_mv.as_mv.col >> 3);

  if (xoffset | yoffset) {

    return vfp->svf(in_what, in_what_stride, xoffset, yoffset, what,

                    what_stride, sse);

  } else {

    return vfp->vf(what, what_stride, in_what, in_what_stride, sse);

  }

}

static int get_prediction_error(BLOCK *be, BLOCKD *b) {

  unsigned char *sptr;

  unsigned char *dptr;

  sptr = (*(be->base_src) + be->src);

  dptr = b->predictor;

  return vpx_get4x4sse_cs(sptr, be->src_stride, dptr, 16);

}

static int pick_intra4x4block(MACROBLOCK *x, int ib,

                              B_PREDICTION_MODE *best_mode,

                              const int *mode_costs,

                              int *bestrate, int *bestdistortion) {

  BLOCKD *b = &x->e_mbd.block[ib];

  BLOCK *be = &x->block[ib];

  int dst_stride = x->e_mbd.dst.y_stride;

  unsigned char *dst = x->e_mbd.dst.y_buffer + b->offset;

  B_PREDICTION_MODE mode;

  int best_rd = INT_MAX;

  int rate;

  int distortion;

  unsigned char *Above = dst - dst_stride;

  unsigned char *yleft = dst - 1;

  unsigned char top_left = Above[-1];

  for (mode = B_DC_PRED; mode <= B_HE_PRED; ++mode) {

    int this_rd;

    rate = mode_costs[mode];

    vp8_intra4x4_predict(Above, yleft, dst_stride, mode, b->predictor, 16,

                         top_left);

    distortion = get_prediction_error(be, b);

    this_rd = RDCOST(x->rdmult, x->rddiv, rate, distortion);

    if (this_rd < best_rd) {

      *bestrate = rate;

      *bestdistortion = distortion;

      best_rd = this_rd;

      *best_mode = mode;

    }

  }

  b->bmi.as_mode = *best_mode;

  vp8_encode_intra4x4block(x, ib);

  return best_rd;

}

static int pick_intra4x4mby_modes(MACROBLOCK *mb, int *Rate, int *best_dist) {

  MACROBLOCKD *const xd = &mb->e_mbd;

  int i;

  int cost = mb->mbmode_cost[xd->frame_type][B_PRED];

  int error;

  int distortion = 0;

  const int *bmode_costs;

  intra_prediction_down_copy(xd, xd->dst.y_buffer - xd->dst.y_stride + 16);

  bmode_costs = mb->inter_bmode_costs;

  for (i = 0; i < 16; ++i) {

    MODE_INFO *const mic = xd->mode_info_context;

    const int mis = xd->mode_info_stride;

    B_PREDICTION_MODE best_mode = B_MODE_COUNT;

    int r = 0, d = 0;

    if (mb->e_mbd.frame_type == KEY_FRAME) {

      const B_PREDICTION_MODE A = above_block_mode(mic, i, mis);

      const B_PREDICTION_MODE L = left_block_mode(mic, i);

      bmode_costs = mb->bmode_costs[A][L];

    }

    pick_intra4x4block(mb, i, &best_mode, bmode_costs, &r, &d);

    cost += r;

    distortion += d;

    assert(best_mode != B_MODE_COUNT);

    mic->bmi[i].as_mode = best_mode;

    /* Break out case where we have already exceeded best so far value

     * that was passed in

     */

    if (distortion > *best_dist) break;

  }

  *Rate = cost;

  if (i == 16) {

    *best_dist = distortion;

    error = RDCOST(mb->rdmult, mb->rddiv, cost, distortion);

  } else {

    *best_dist = INT_MAX;

    error = INT_MAX;

  }

  return error;

}

static void pick_intra_mbuv_mode(MACROBLOCK *mb) {

  MACROBLOCKD *x = &mb->e_mbd;

  unsigned char *uabove_row = x->dst.u_buffer - x->dst.uv_stride;

  unsigned char *vabove_row = x->dst.v_buffer - x->dst.uv_stride;

  unsigned char *usrc_ptr = (mb->block[16].src + *mb->block[16].base_src);

  unsigned char *vsrc_ptr = (mb->block[20].src + *mb->block[20].base_src);

  int uvsrc_stride = mb->block[16].src_stride;

  unsigned char uleft_col[8];

  unsigned char vleft_col[8];

  unsigned char utop_left = uabove_row[-1];

  unsigned char vtop_left = vabove_row[-1];

  int i, j;

  int expected_udc;

  int expected_vdc;

  int shift;

  int Uaverage = 0;

  int Vaverage = 0;

  int diff;

  int pred_error[4] = { 0, 0, 0, 0 }, best_error = INT_MAX;

  MB_PREDICTION_MODE best_mode = MB_MODE_COUNT;

  for (i = 0; i < 8; ++i) {

    uleft_col[i] = x->dst.u_buffer[i * x->dst.uv_stride - 1];

    vleft_col[i] = x->dst.v_buffer[i * x->dst.uv_stride - 1];

  }

  if (!x->up_available && !x->left_available) {

    expected_udc = 128;

    expected_vdc = 128;

  } else {

    shift = 2;

    if (x->up_available) {

      for (i = 0; i < 8; ++i) {

        Uaverage += uabove_row[i];

        Vaverage += vabove_row[i];

      }

      shift++;

    }

    if (x->left_available) {

      for (i = 0; i < 8; ++i) {

        Uaverage += uleft_col[i];

        Vaverage += vleft_col[i];

      }

      shift++;

    }

    expected_udc = (Uaverage + (1 << (shift - 1))) >> shift;

    expected_vdc = (Vaverage + (1 << (shift - 1))) >> shift;

  }

  for (i = 0; i < 8; ++i) {

    for (j = 0; j < 8; ++j) {

      int predu = uleft_col[i] + uabove_row[j] - utop_left;

      int predv = vleft_col[i] + vabove_row[j] - vtop_left;

      int u_p, v_p;

      u_p = usrc_ptr[j];

      v_p = vsrc_ptr[j];

      if (predu < 0) predu = 0;

      if (predu > 255) predu = 255;

      if (predv < 0) predv = 0;

      if (predv > 255) predv = 255;

      diff = u_p - expected_udc;

      pred_error[DC_PRED] += diff * diff;

      diff = v_p - expected_vdc;

      pred_error[DC_PRED] += diff * diff;

      diff = u_p - uabove_row[j];

      pred_error[V_PRED] += diff * diff;

      diff = v_p - vabove_row[j];

      pred_error[V_PRED] += diff * diff;

      diff = u_p - uleft_col[i];

      pred_error[H_PRED] += diff * diff;

      diff = v_p - vleft_col[i];

      pred_error[H_PRED] += diff * diff;

      diff = u_p - predu;

      pred_error[TM_PRED] += diff * diff;

      diff = v_p - predv;

      pred_error[TM_PRED] += diff * diff;

    }

    usrc_ptr += uvsrc_stride;

    vsrc_ptr += uvsrc_stride;

    if (i == 3) {

      usrc_ptr = (mb->block[18].src + *mb->block[18].base_src);

      vsrc_ptr = (mb->block[22].src + *mb->block[22].base_src);

    }

  }

  for (i = DC_PRED; i <= TM_PRED; ++i) {

    if (best_error > pred_error[i]) {

      best_error = pred_error[i];

      best_mode = (MB_PREDICTION_MODE)i;

    }

  }

  assert(best_mode != MB_MODE_COUNT);

  mb->e_mbd.mode_info_context->mbmi.uv_mode = best_mode;

}

static void update_mvcount(MACROBLOCK *x, int_mv *best_ref_mv) {

  MACROBLOCKD *xd = &x->e_mbd;

  /* Split MV modes currently not supported when RD is nopt enabled,

   * therefore, only need to modify MVcount in NEWMV mode. */

  if (xd->mode_info_context->mbmi.mode == NEWMV) {

    x->MVcount[0][mv_max + ((xd->mode_info_context->mbmi.mv.as_mv.row -

                             best_ref_mv->as_mv.row) >>

                            1)]++;

    x->MVcount[1][mv_max + ((xd->mode_info_context->mbmi.mv.as_mv.col -

                             best_ref_mv->as_mv.col) >>

                            1)]++;

  }

}

#if CONFIG_MULTI_RES_ENCODING

static void get_lower_res_motion_info(VP8_COMP *cpi, MACROBLOCKD *xd,

                                      int *dissim, int *parent_ref_frame,

                                      MB_PREDICTION_MODE *parent_mode,

                                      int_mv *parent_ref_mv, int mb_row,

                                      int mb_col) {

  LOWER_RES_MB_INFO *store_mode_info =

      ((LOWER_RES_FRAME_INFO *)cpi->oxcf.mr_low_res_mode_info)->mb_info;

  unsigned int parent_mb_index;

  /* Consider different down_sampling_factor.  */

  {

    /* TODO: Removed the loop that supports special down_sampling_factor

     * such as 2, 4, 8. Will revisit it if needed.

     * Should also try using a look-up table to see if it helps

     * performance. */

    int parent_mb_row, parent_mb_col;

    parent_mb_row = mb_row * cpi->oxcf.mr_down_sampling_factor.den /

                    cpi->oxcf.mr_down_sampling_factor.num;

    parent_mb_col = mb_col * cpi->oxcf.mr_down_sampling_factor.den /

                    cpi->oxcf.mr_down_sampling_factor.num;

    parent_mb_index = parent_mb_row * cpi->mr_low_res_mb_cols + parent_mb_col;

  }

  /* Read lower-resolution mode & motion result from memory.*/

  *parent_ref_frame = store_mode_info[parent_mb_index].ref_frame;

  *parent_mode = store_mode_info[parent_mb_index].mode;

  *dissim = store_mode_info[parent_mb_index].dissim;

  /* For highest-resolution encoder, adjust dissim value. Lower its quality

   * for good performance. */

  if (cpi->oxcf.mr_encoder_id == (cpi->oxcf.mr_total_resolutions - 1))

    *dissim >>= 1;

  if (*parent_ref_frame != INTRA_FRAME) {

    /* Consider different down_sampling_factor.

     * The result can be rounded to be more precise, but it takes more time.

     */

    (*parent_ref_mv).as_mv.row = store_mode_info[parent_mb_index].mv.as_mv.row *

                                 cpi->oxcf.mr_down_sampling_factor.num /

                                 cpi->oxcf.mr_down_sampling_factor.den;

    (*parent_ref_mv).as_mv.col = store_mode_info[parent_mb_index].mv.as_mv.col *

                                 cpi->oxcf.mr_down_sampling_factor.num /

                                 cpi->oxcf.mr_down_sampling_factor.den;

    vp8_clamp_mv2(parent_ref_mv, xd);

  }

}

#endif

static void check_for_encode_breakout(unsigned int sse, MACROBLOCK *x) {

  MACROBLOCKD *xd = &x->e_mbd;

  unsigned int threshold =

      (xd->block[0].dequant[1] * xd->block[0].dequant[1] >> 4);

  if (threshold < x->encode_breakout) threshold = x->encode_breakout;

  if (sse < threshold) {

    /* Check u and v to make sure skip is ok */

    unsigned int sse2 = 0;

    sse2 = VP8_UVSSE(x);

    if (sse2 * 2 < x->encode_breakout) {

      x->skip = 1;

    } else {

      x->skip = 0;

    }

  }

}

static int evaluate_inter_mode(unsigned int *sse, int rate2, int *distortion2,

                               VP8_COMP *cpi, MACROBLOCK *x, int rd_adj) {

  MB_PREDICTION_MODE this_mode = x->e_mbd.mode_info_context->mbmi.mode;

  int_mv mv = x->e_mbd.mode_info_context->mbmi.mv;

  int this_rd;

  int denoise_aggressive = 0;

  /* Exit early and don't compute the distortion if this macroblock

   * is marked inactive. */

  if (cpi->active_map_enabled && x->active_ptr[0] == 0) {

    *sse = 0;

    *distortion2 = 0;

    x->skip = 1;

    return INT_MAX;

  }

  if ((this_mode != NEWMV) || !(cpi->sf.half_pixel_search) ||

      cpi->common.full_pixel == 1) {

    *distortion2 =

        vp8_get_inter_mbpred_error(x, &cpi->fn_ptr[BLOCK_16X16], sse, mv);

  }

  this_rd = RDCOST(x->rdmult, x->rddiv, rate2, *distortion2);

#if CONFIG_TEMPORAL_DENOISING

  if (cpi->oxcf.noise_sensitivity > 0) {

    denoise_aggressive =

        (cpi->denoiser.denoiser_mode == kDenoiserOnYUVAggressive) ? 1 : 0;

  }

#endif

  // Adjust rd for ZEROMV and LAST, if LAST is the closest reference frame.

  // TODO: We should also add condition on distance of closest to current.

  if (!cpi->oxcf.screen_content_mode && this_mode == ZEROMV &&

      x->e_mbd.mode_info_context->mbmi.ref_frame == LAST_FRAME &&

      (denoise_aggressive || (cpi->closest_reference_frame == LAST_FRAME))) {

    // No adjustment if block is considered to be skin area.

    if (x->is_skin) rd_adj = 100;

    this_rd = (int)(((int64_t)this_rd) * rd_adj / 100);

  }

  check_for_encode_breakout(*sse, x);

  return this_rd;

}

static void calculate_zeromv_rd_adjustment(VP8_COMP *cpi, MACROBLOCK *x,

                                           int *rd_adjustment) {

  MODE_INFO *mic = x->e_mbd.mode_info_context;

  int_mv mv_l, mv_a, mv_al;

  int local_motion_check = 0;

  if (cpi->lf_zeromv_pct > 40) {

    /* left mb */

    mic -= 1;

    mv_l = mic->mbmi.mv;

    if (mic->mbmi.ref_frame != INTRA_FRAME) {

      if (abs(mv_l.as_mv.row) < 8 && abs(mv_l.as_mv.col) < 8) {

        local_motion_check++;

      }

    }

    /* above-left mb */

    mic -= x->e_mbd.mode_info_stride;

    mv_al = mic->mbmi.mv;

    if (mic->mbmi.ref_frame != INTRA_FRAME) {

      if (abs(mv_al.as_mv.row) < 8 && abs(mv_al.as_mv.col) < 8) {

        local_motion_check++;

      }

    }

    /* above mb */

    mic += 1;

    mv_a = mic->mbmi.mv;

    if (mic->mbmi.ref_frame != INTRA_FRAME) {

      if (abs(mv_a.as_mv.row) < 8 && abs(mv_a.as_mv.col) < 8) {

        local_motion_check++;

      }

    }

    if (((!x->e_mbd.mb_to_top_edge || !x->e_mbd.mb_to_left_edge) &&

         local_motion_check > 0) ||

        local_motion_check > 2) {

      *rd_adjustment = 80;

    } else if (local_motion_check > 0) {

      *rd_adjustment = 90;

    }

  }

}

void vp8_pick_inter_mode(VP8_COMP *cpi, MACROBLOCK *x, int recon_yoffset,

                         int recon_uvoffset, int *returnrate,

                         int *returndistortion, int *returnintra, int mb_row,

                         int mb_col) {

  BLOCK *b = &x->block[0];

  BLOCKD *d = &x->e_mbd.block[0];

  MACROBLOCKD *xd = &x->e_mbd;

  MB_MODE_INFO best_mbmode;

  int_mv best_ref_mv_sb[2];

  int_mv mode_mv_sb[2][MB_MODE_COUNT];

  int_mv best_ref_mv;

  int_mv *mode_mv;

  MB_PREDICTION_MODE this_mode;

  int num00;

  int mdcounts[4];

  int best_rd = INT_MAX;

  int rd_adjustment = 100;

  int best_intra_rd = INT_MAX;

  int mode_index;

  int rate;

  int rate2;

  int distortion2;

  int bestsme = INT_MAX;

  int best_mode_index = 0;

  unsigned int sse = UINT_MAX, best_rd_sse = UINT_MAX;

#if CONFIG_TEMPORAL_DENOISING

  unsigned int zero_mv_sse = UINT_MAX, best_sse = UINT_MAX;

#endif

  int sf_improved_mv_pred = cpi->sf.improved_mv_pred;

#if CONFIG_MULTI_RES_ENCODING

  int dissim = INT_MAX;

  int parent_ref_frame = 0;

  int_mv parent_ref_mv;

  MB_PREDICTION_MODE parent_mode = 0;

  int parent_ref_valid = 0;

#endif

  int_mv mvp;

  int near_sadidx[8] = { 0, 1, 2, 3, 4, 5, 6, 7 };

  int saddone = 0;

  /* search range got from mv_pred(). It uses step_param levels. (0-7) */

  int sr = 0;

  unsigned char *plane[4][3];

  int ref_frame_map[4];

  int sign_bias = 0;

  int dot_artifact_candidate = 0;

  get_predictor_pointers(cpi, plane, recon_yoffset, recon_uvoffset);

  // If the current frame is using LAST as a reference, check for

  // biasing the mode selection for dot artifacts.

  if (cpi->ref_frame_flags & VP8_LAST_FRAME) {

    unsigned char *target_y = x->src.y_buffer;

    unsigned char *target_u = x->block[16].src + *x->block[16].base_src;

    unsigned char *target_v = x->block[20].src + *x->block[20].base_src;

    int stride = x->src.y_stride;

    int stride_uv = x->block[16].src_stride;

#if CONFIG_TEMPORAL_DENOISING

    if (cpi->oxcf.noise_sensitivity) {

      const int uv_denoise = (cpi->oxcf.noise_sensitivity >= 2) ? 1 : 0;

      target_y =

          cpi->denoiser.yv12_running_avg[LAST_FRAME].y_buffer + recon_yoffset;

      stride = cpi->denoiser.yv12_running_avg[LAST_FRAME].y_stride;

      if (uv_denoise) {

        target_u = cpi->denoiser.yv12_running_avg[LAST_FRAME].u_buffer +

                   recon_uvoffset;

        target_v = cpi->denoiser.yv12_running_avg[LAST_FRAME].v_buffer +

                   recon_uvoffset;

        stride_uv = cpi->denoiser.yv12_running_avg[LAST_FRAME].uv_stride;

      }

    }

#endif

    dot_artifact_candidate = check_dot_artifact_candidate(

        cpi, x, target_y, stride, plane[LAST_FRAME][0], mb_row, mb_col, 0);

    // If not found in Y channel, check UV channel.

    if (!dot_artifact_candidate) {

      dot_artifact_candidate = check_dot_artifact_candidate(

          cpi, x, target_u, stride_uv, plane[LAST_FRAME][1], mb_row, mb_col, 1);

      if (!dot_artifact_candidate) {

        dot_artifact_candidate = check_dot_artifact_candidate(

            cpi, x, target_v, stride_uv, plane[LAST_FRAME][2], mb_row, mb_col,

            2);

      }

    }

  }

#if CONFIG_MULTI_RES_ENCODING

  // |parent_ref_valid| will be set here if potentially we can do mv resue for

  // this higher resol (|cpi->oxcf.mr_encoder_id| > 0) frame.

  // |parent_ref_valid| may be reset depending on |parent_ref_frame| for

  // the current macroblock below.

  parent_ref_valid = cpi->oxcf.mr_encoder_id && cpi->mr_low_res_mv_avail;

  if (parent_ref_valid) {

    int parent_ref_flag;

    get_lower_res_motion_info(cpi, xd, &dissim, &parent_ref_frame, &parent_mode,

                              &parent_ref_mv, mb_row, mb_col);

    /* TODO(jkoleszar): The references available (ref_frame_flags) to the

     * lower res encoder should match those available to this encoder, but

     * there seems to be a situation where this mismatch can happen in the

     * case of frame dropping and temporal layers. For example,

     * GOLD being disallowed in ref_frame_flags, but being returned as

     * parent_ref_frame.

     *

     * In this event, take the conservative approach of disabling the

     * lower res info for this MB.

     */

    parent_ref_flag = 0;

    // Note availability for mv reuse is only based on last and golden.

    if (parent_ref_frame == LAST_FRAME)

      parent_ref_flag = (cpi->ref_frame_flags & VP8_LAST_FRAME);

    else if (parent_ref_frame == GOLDEN_FRAME)

      parent_ref_flag = (cpi->ref_frame_flags & VP8_GOLD_FRAME);

    // assert(!parent_ref_frame || parent_ref_flag);

    // If |parent_ref_frame| did not match either last or golden then

    // shut off mv reuse.

    if (parent_ref_frame && !parent_ref_flag) parent_ref_valid = 0;

    // Don't do mv reuse since we want to allow for another mode besides

    // ZEROMV_LAST to remove dot artifact.

    if (dot_artifact_candidate) parent_ref_valid = 0;

  }

#endif

  // Check if current macroblock is in skin area.

  x->is_skin = 0;

  if (!cpi->oxcf.screen_content_mode) {

    int block_index = mb_row * cpi->common.mb_cols + mb_col;

    x->is_skin = cpi->skin_map[block_index];

  }

#if CONFIG_TEMPORAL_DENOISING

  if (cpi->oxcf.noise_sensitivity) {

    // Under aggressive denoising mode, should we use skin map to reduce

    // denoiser

    // and ZEROMV bias? Will need to revisit the accuracy of this detection for

    // very noisy input. For now keep this as is (i.e., don't turn it off).

    // if (cpi->denoiser.denoiser_mode == kDenoiserOnYUVAggressive)

    //   x->is_skin = 0;

  }

#endif

  mode_mv = mode_mv_sb[sign_bias];

  best_ref_mv.as_int = 0;

  memset(mode_mv_sb, 0, sizeof(mode_mv_sb));

  memset(&best_mbmode, 0, sizeof(best_mbmode));

/* Setup search priorities */

#if CONFIG_MULTI_RES_ENCODING

  if (parent_ref_valid && parent_ref_frame && dissim < 8) {

    ref_frame_map[0] = -1;

    ref_frame_map[1] = parent_ref_frame;

    ref_frame_map[2] = -1;

    ref_frame_map[3] = -1;

  } else

#endif

    get_reference_search_order(cpi, ref_frame_map);

  /* Check to see if there is at least 1 valid reference frame that we need

   * to calculate near_mvs.

   */

  if (ref_frame_map[1] > 0) {

    sign_bias = vp8_find_near_mvs_bias(

        &x->e_mbd, x->e_mbd.mode_info_context, mode_mv_sb, best_ref_mv_sb,

        mdcounts, ref_frame_map[1], cpi->common.ref_frame_sign_bias);

    mode_mv = mode_mv_sb[sign_bias];

    best_ref_mv.as_int = best_ref_mv_sb[sign_bias].as_int;

  }

  /* Count of the number of MBs tested so far this frame */

  x->mbs_tested_so_far++;

  *returnintra = INT_MAX;

  x->skip = 0;

  x->e_mbd.mode_info_context->mbmi.ref_frame = INTRA_FRAME;

  /* If the frame has big static background and current MB is in low

  *  motion area, its mode decision is biased to ZEROMV mode.

  *  No adjustment if cpu_used is <= -12 (i.e., cpi->Speed >= 12).

  *  At such speed settings, ZEROMV is already heavily favored.

  */

  if (cpi->Speed < 12) {

    calculate_zeromv_rd_adjustment(cpi, x, &rd_adjustment);

  }

#if CONFIG_TEMPORAL_DENOISING

  if (cpi->oxcf.noise_sensitivity) {

    rd_adjustment = (int)(rd_adjustment *

                          cpi->denoiser.denoise_pars.pickmode_mv_bias / 100);

  }

#endif

  if (dot_artifact_candidate) {

    // Bias against ZEROMV_LAST mode.

    rd_adjustment = 150;

  }

  /* if we encode a new mv this is important

   * find the best new motion vector

   */

  for (mode_index = 0; mode_index < MAX_MODES; ++mode_index) {

    int frame_cost;

    int this_rd = INT_MAX;

    int this_ref_frame = ref_frame_map[vp8_ref_frame_order[mode_index]];

    if (best_rd <= x->rd_threshes[mode_index]) continue;

    if (this_ref_frame < 0) continue;

    x->e_mbd.mode_info_context->mbmi.ref_frame = this_ref_frame;

    /* everything but intra */

    if (x->e_mbd.mode_info_context->mbmi.ref_frame) {

      x->e_mbd.pre.y_buffer = plane[this_ref_frame][0];

      x->e_mbd.pre.u_buffer = plane[this_ref_frame][1];

      x->e_mbd.pre.v_buffer = plane[this_ref_frame][2];

      if (sign_bias != cpi->common.ref_frame_sign_bias[this_ref_frame]) {

        sign_bias = cpi->common.ref_frame_sign_bias[this_ref_frame];

        mode_mv = mode_mv_sb[sign_bias];

        best_ref_mv.as_int = best_ref_mv_sb[sign_bias].as_int;

      }

#if CONFIG_MULTI_RES_ENCODING

      if (parent_ref_valid) {

        if (vp8_mode_order[mode_index] == NEARESTMV &&

            mode_mv[NEARESTMV].as_int == 0)

          continue;

        if (vp8_mode_order[mode_index] == NEARMV && mode_mv[NEARMV].as_int == 0)

          continue;

        if (vp8_mode_order[mode_index] == NEWMV && parent_mode == ZEROMV &&

            best_ref_mv.as_int == 0)

          continue;

        else if (vp8_mode_order[mode_index] == NEWMV && dissim == 0 &&

                 best_ref_mv.as_int == parent_ref_mv.as_int)

          continue;

      }

#endif

    }

    /* Check to see if the testing frequency for this mode is at its max

     * If so then prevent it from being tested and increase the threshold

     * for its testing */

    if (x->mode_test_hit_counts[mode_index] &&

        (cpi->mode_check_freq[mode_index] > 1)) {

      if (x->mbs_tested_so_far <= (cpi->mode_check_freq[mode_index] *

                                   x->mode_test_hit_counts[mode_index])) {

        /* Increase the threshold for coding this mode to make it less

         * likely to be chosen */

        x->rd_thresh_mult[mode_index] += 4;

        if (x->rd_thresh_mult[mode_index] > MAX_THRESHMULT) {

          x->rd_thresh_mult[mode_index] = MAX_THRESHMULT;

        }

        x->rd_threshes[mode_index] =

            (cpi->rd_baseline_thresh[mode_index] >> 7) *

            x->rd_thresh_mult[mode_index];

        continue;

      }

    }

    /* We have now reached the point where we are going to test the current

     * mode so increment the counter for the number of times it has been

     * tested */

    x->mode_test_hit_counts[mode_index]++;

    rate2 = 0;

    distortion2 = 0;

    this_mode = vp8_mode_order[mode_index];

    x->e_mbd.mode_info_context->mbmi.mode = this_mode;

    x->e_mbd.mode_info_context->mbmi.uv_mode = DC_PRED;

    /* Work out the cost assosciated with selecting the reference frame */

    frame_cost = x->ref_frame_cost[x->e_mbd.mode_info_context->mbmi.ref_frame];

    rate2 += frame_cost;

    /* Only consider ZEROMV/ALTREF_FRAME for alt ref frame,

     * unless ARNR filtering is enabled in which case we want

     * an unfiltered alternative */

    if (cpi->is_src_frame_alt_ref && (cpi->oxcf.arnr_max_frames == 0)) {

      if (this_mode != ZEROMV ||

          x->e_mbd.mode_info_context->mbmi.ref_frame != ALTREF_FRAME) {

        continue;

      }

    }

    switch (this_mode) {

      case B_PRED:

        /* Pass best so far to pick_intra4x4mby_modes to use as breakout */