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 /*

  *  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 <limits.h>

 #include <math.h>

 #include <stdio.h>

 #include "./vp9_rtcd.h"

 #include "./vpx_config.h"

 #include "vpx_ports/vpx_timer.h"

 #include "vp9/common/vp9_common.h"

 #include "vp9/common/vp9_entropy.h"

 #include "vp9/common/vp9_entropymode.h"

 #include "vp9/common/vp9_extend.h"

 #include "vp9/common/vp9_findnearmv.h"

 #include "vp9/common/vp9_idct.h"

 #include "vp9/common/vp9_mvref_common.h"

 #include "vp9/common/vp9_pred_common.h"

 #include "vp9/common/vp9_quant_common.h"

 #include "vp9/common/vp9_reconintra.h"

 #include "vp9/common/vp9_reconinter.h"

 #include "vp9/common/vp9_seg_common.h"

 #include "vp9/common/vp9_tile_common.h"

 #include "vp9/encoder/vp9_encodeframe.h"

 #include "vp9/encoder/vp9_encodeintra.h"

 #include "vp9/encoder/vp9_encodemb.h"

 #include "vp9/encoder/vp9_encodemv.h"

 #include "vp9/encoder/vp9_onyx_int.h"

 #include "vp9/encoder/vp9_rdopt.h"

 #include "vp9/encoder/vp9_segmentation.h"

 #include "vp9/common/vp9_systemdependent.h"

 #include "vp9/encoder/vp9_tokenize.h"

 #include "vp9/encoder/vp9_vaq.h"

 #define DBG_PRNT_SEGMAP 0

 // #define ENC_DEBUG

 #ifdef ENC_DEBUG

 int enc_debug = 0;

 #endif

 static INLINE uint8_t *get_sb_index(MACROBLOCK *x, BLOCK_SIZE subsize) {

   switch (subsize) {

     case BLOCK_64X64:

     case BLOCK_64X32:

     case BLOCK_32X64:

     case BLOCK_32X32:

       return &x->sb_index;

     case BLOCK_32X16:

     case BLOCK_16X32:

     case BLOCK_16X16:

       return &x->mb_index;

     case BLOCK_16X8:

     case BLOCK_8X16:

     case BLOCK_8X8:

       return &x->b_index;

     case BLOCK_8X4:

     case BLOCK_4X8:

     case BLOCK_4X4:

       return &x->ab_index;

     default:

       assert(0);

       return NULL;

   }

 }

 static void encode_superblock(VP9_COMP *cpi, TOKENEXTRA **t, int output_enabled,

                               int mi_row, int mi_col, BLOCK_SIZE bsize);

 static void adjust_act_zbin(VP9_COMP *cpi, MACROBLOCK *x);

 /* activity_avg must be positive, or flat regions could get a zero weight

  *  (infinite lambda), which confounds analysis.

  * This also avoids the need for divide by zero checks in

  *  vp9_activity_masking().

  */

 #define ACTIVITY_AVG_MIN (64)

 /* Motion vector component magnitude threshold for defining fast motion. */

 #define FAST_MOTION_MV_THRESH (24)

 /* This is used as a reference when computing the source variance for the

  *  purposes of activity masking.

  * Eventually this should be replaced by custom no-reference routines,

  *  which will be faster.

  */

 static const uint8_t VP9_VAR_OFFS[64] = {

   128, 128, 128, 128, 128, 128, 128, 128,

   128, 128, 128, 128, 128, 128, 128, 128,

   128, 128, 128, 128, 128, 128, 128, 128,

   128, 128, 128, 128, 128, 128, 128, 128,

   128, 128, 128, 128, 128, 128, 128, 128,

   128, 128, 128, 128, 128, 128, 128, 128,

   128, 128, 128, 128, 128, 128, 128, 128,

   128, 128, 128, 128, 128, 128, 128, 128

 };

 static unsigned int get_sby_perpixel_variance(VP9_COMP *cpi, MACROBLOCK *x,

                                               BLOCK_SIZE bs) {

   unsigned int var, sse;

   var = cpi->fn_ptr[bs].vf(x->plane[0].src.buf,

                            x->plane[0].src.stride,

                            VP9_VAR_OFFS, 0, &sse);

   return (var + (1 << (num_pels_log2_lookup[bs] - 1))) >>

       num_pels_log2_lookup[bs];

 }

 // Original activity measure from Tim T's code.

 static unsigned int tt_activity_measure(MACROBLOCK *x) {

   unsigned int act;

   unsigned int sse;

   /* TODO: This could also be done over smaller areas (8x8), but that would

    *  require extensive changes elsewhere, as lambda is assumed to be fixed

    *  over an entire MB in most of the code.

    * Another option is to compute four 8x8 variances, and pick a single

    *  lambda using a non-linear combination (e.g., the smallest, or second

    *  smallest, etc.).

    */

   act = vp9_variance16x16(x->plane[0].src.buf, x->plane[0].src.stride,

                           VP9_VAR_OFFS, 0, &sse);

   act <<= 4;

   /* If the region is flat, lower the activity some more. */

   if (act < 8 << 12)

     act = act < 5 << 12 ? act : 5 << 12;

   return act;

 }

 // Stub for alternative experimental activity measures.

 static unsigned int alt_activity_measure(MACROBLOCK *x, int use_dc_pred) {

   return vp9_encode_intra(x, use_dc_pred);

 }

 // Measure the activity of the current macroblock

 // What we measure here is TBD so abstracted to this function

 #define ALT_ACT_MEASURE 1

 static unsigned int mb_activity_measure(MACROBLOCK *x, int mb_row, int mb_col) {

   unsigned int mb_activity;

   if (ALT_ACT_MEASURE) {

     int use_dc_pred = (mb_col || mb_row) && (!mb_col || !mb_row);

     // Or use and alternative.

     mb_activity = alt_activity_measure(x, use_dc_pred);

   } else {

     // Original activity measure from Tim T's code.

     mb_activity = tt_activity_measure(x);

   }

   if (mb_activity < ACTIVITY_AVG_MIN)

     mb_activity = ACTIVITY_AVG_MIN;

   return mb_activity;

 }

 // Calculate an "average" mb activity value for the frame

 #define ACT_MEDIAN 0

 static void calc_av_activity(VP9_COMP *cpi, int64_t activity_sum) {

 #if ACT_MEDIAN

   // Find median: Simple n^2 algorithm for experimentation

   {

     unsigned int median;

     unsigned int i, j;

     unsigned int *sortlist;

     unsigned int tmp;

     // Create a list to sort to

     CHECK_MEM_ERROR(&cpi->common, sortlist, vpx_calloc(sizeof(unsigned int),

                     cpi->common.MBs));

     // Copy map to sort list

     vpx_memcpy(sortlist, cpi->mb_activity_map,

         sizeof(unsigned int) * cpi->common.MBs);

     // Ripple each value down to its correct position

     for (i = 1; i < cpi->common.MBs; i ++) {

       for (j = i; j > 0; j --) {

         if (sortlist[j] < sortlist[j - 1]) {

           // Swap values

           tmp = sortlist[j - 1];

           sortlist[j - 1] = sortlist[j];

           sortlist[j] = tmp;

         } else {

           break;

         }

       }

     }

     // Even number MBs so estimate median as mean of two either side.

     median = (1 + sortlist[cpi->common.MBs >> 1] +

         sortlist[(cpi->common.MBs >> 1) + 1]) >> 1;

     cpi->activity_avg = median;

     vpx_free(sortlist);

   }

 #else

   // Simple mean for now

   cpi->activity_avg = (unsigned int) (activity_sum / cpi->common.MBs);

 #endif  // ACT_MEDIAN

   if (cpi->activity_avg < ACTIVITY_AVG_MIN)

     cpi->activity_avg = ACTIVITY_AVG_MIN;

   // Experimental code: return fixed value normalized for several clips

   if (ALT_ACT_MEASURE)

     cpi->activity_avg = 100000;

 }

 #define USE_ACT_INDEX   0

 #define OUTPUT_NORM_ACT_STATS   0

 #if USE_ACT_INDEX

 // Calculate an activity index for each mb

 static void calc_activity_index(VP9_COMP *cpi, MACROBLOCK *x) {

   VP9_COMMON *const cm = &cpi->common;

   int mb_row, mb_col;

   int64_t act;

   int64_t a;

   int64_t b;

 #if OUTPUT_NORM_ACT_STATS

   FILE *f = fopen("norm_act.stt", "a");

   fprintf(f, "\n%12d\n", cpi->activity_avg);

 #endif

   // Reset pointers to start of activity map

   x->mb_activity_ptr = cpi->mb_activity_map;

   // Calculate normalized mb activity number.

   for (mb_row = 0; mb_row < cm->mb_rows; mb_row++) {

     // for each macroblock col in image

     for (mb_col = 0; mb_col < cm->mb_cols; mb_col++) {

       // Read activity from the map

       act = *(x->mb_activity_ptr);

       // Calculate a normalized activity number

       a = act + 4 * cpi->activity_avg;

       b = 4 * act + cpi->activity_avg;

       if (b >= a)

       *(x->activity_ptr) = (int)((b + (a >> 1)) / a) - 1;

       else

       *(x->activity_ptr) = 1 - (int)((a + (b >> 1)) / b);

 #if OUTPUT_NORM_ACT_STATS

       fprintf(f, " %6d", *(x->mb_activity_ptr));

 #endif

       // Increment activity map pointers

       x->mb_activity_ptr++;

     }

 #if OUTPUT_NORM_ACT_STATS

     fprintf(f, "\n");

 #endif

   }

 #if OUTPUT_NORM_ACT_STATS

   fclose(f);

 #endif

 }

 #endif  // USE_ACT_INDEX

 // Loop through all MBs. Note activity of each, average activity and

 // calculate a normalized activity for each

 static void build_activity_map(VP9_COMP *cpi) {

   MACROBLOCK * const x = &cpi->mb;

   MACROBLOCKD *xd = &x->e_mbd;

   VP9_COMMON * const cm = &cpi->common;

 #if ALT_ACT_MEASURE

   YV12_BUFFER_CONFIG *new_yv12 = get_frame_new_buffer(cm);

   int recon_yoffset;

   int recon_y_stride = new_yv12->y_stride;

 #endif

   int mb_row, mb_col;

   unsigned int mb_activity;

   int64_t activity_sum = 0;

   x->mb_activity_ptr = cpi->mb_activity_map;

   // for each macroblock row in image

   for (mb_row = 0; mb_row < cm->mb_rows; mb_row++) {

 #if ALT_ACT_MEASURE

     // reset above block coeffs

     xd->up_available = (mb_row != 0);

     recon_yoffset = (mb_row * recon_y_stride * 16);

 #endif

     // for each macroblock col in image

     for (mb_col = 0; mb_col < cm->mb_cols; mb_col++) {

 #if ALT_ACT_MEASURE

       xd->plane[0].dst.buf = new_yv12->y_buffer + recon_yoffset;

       xd->left_available = (mb_col != 0);

       recon_yoffset += 16;

 #endif

       // measure activity

       mb_activity = mb_activity_measure(x, mb_row, mb_col);

       // Keep frame sum

       activity_sum += mb_activity;

       // Store MB level activity details.

       *x->mb_activity_ptr = mb_activity;

       // Increment activity map pointer

       x->mb_activity_ptr++;

       // adjust to the next column of source macroblocks

       x->plane[0].src.buf += 16;

     }

     // adjust to the next row of mbs

     x->plane[0].src.buf += 16 * x->plane[0].src.stride - 16 * cm->mb_cols;

   }

   // Calculate an "average" MB activity

   calc_av_activity(cpi, activity_sum);

 #if USE_ACT_INDEX

   // Calculate an activity index number of each mb

   calc_activity_index(cpi, x);

 #endif

 }

 // Macroblock activity masking

 void vp9_activity_masking(VP9_COMP *cpi, MACROBLOCK *x) {

 #if USE_ACT_INDEX

   x->rdmult += *(x->mb_activity_ptr) * (x->rdmult >> 2);

   x->errorperbit = x->rdmult * 100 / (110 * x->rddiv);

   x->errorperbit += (x->errorperbit == 0);

 #else

   int64_t a;

   int64_t b;

   int64_t act = *(x->mb_activity_ptr);

   // Apply the masking to the RD multiplier.

   a = act + (2 * cpi->activity_avg);

   b = (2 * act) + cpi->activity_avg;

   x->rdmult = (unsigned int) (((int64_t) x->rdmult * b + (a >> 1)) / a);

   x->errorperbit = x->rdmult * 100 / (110 * x->rddiv);

   x->errorperbit += (x->errorperbit == 0);

 #endif

   // Activity based Zbin adjustment

   adjust_act_zbin(cpi, x);

 }

 static void update_state(VP9_COMP *cpi, PICK_MODE_CONTEXT *ctx,

                          BLOCK_SIZE bsize, int output_enabled) {

   int i, x_idx, y;

   VP9_COMMON *const cm = &cpi->common;

   MACROBLOCK *const x = &cpi->mb;

   MACROBLOCKD *const xd = &x->e_mbd;

   struct macroblock_plane *const p = x->plane;

   struct macroblockd_plane *const pd = xd->plane;

   MODE_INFO *mi = &ctx->mic;

   MB_MODE_INFO *const mbmi = &xd->mi_8x8[0]->mbmi;

   MODE_INFO *mi_addr = xd->mi_8x8[0];

   int mb_mode_index = ctx->best_mode_index;

   const int mis = cm->mode_info_stride;

   const int mi_width = num_8x8_blocks_wide_lookup[bsize];

   const int mi_height = num_8x8_blocks_high_lookup[bsize];

   int max_plane;

   assert(mi->mbmi.mode < MB_MODE_COUNT);

   assert(mi->mbmi.ref_frame[0] < MAX_REF_FRAMES);

   assert(mi->mbmi.ref_frame[1] < MAX_REF_FRAMES);

   assert(mi->mbmi.sb_type == bsize);

   *mi_addr = *mi;

   max_plane = is_inter_block(mbmi) ? MAX_MB_PLANE : 1;

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

     p[i].coeff = ctx->coeff_pbuf[i][1];

     pd[i].qcoeff = ctx->qcoeff_pbuf[i][1];

     pd[i].dqcoeff = ctx->dqcoeff_pbuf[i][1];

     pd[i].eobs = ctx->eobs_pbuf[i][1];

   }

   for (i = max_plane; i < MAX_MB_PLANE; ++i) {

     p[i].coeff = ctx->coeff_pbuf[i][2];

     pd[i].qcoeff = ctx->qcoeff_pbuf[i][2];

     pd[i].dqcoeff = ctx->dqcoeff_pbuf[i][2];

     pd[i].eobs = ctx->eobs_pbuf[i][2];

   }

   // Restore the coding context of the MB to that that was in place

   // when the mode was picked for it

   for (y = 0; y < mi_height; y++)

     for (x_idx = 0; x_idx < mi_width; x_idx++)

       if ((xd->mb_to_right_edge >> (3 + MI_SIZE_LOG2)) + mi_width > x_idx

           && (xd->mb_to_bottom_edge >> (3 + MI_SIZE_LOG2)) + mi_height > y)

         xd->mi_8x8[x_idx + y * mis] = mi_addr;

   if (cpi->oxcf.aq_mode == VARIANCE_AQ) {

     vp9_mb_init_quantizer(cpi, x);

   }

   // FIXME(rbultje) I'm pretty sure this should go to the end of this block

   // (i.e. after the output_enabled)

   if (bsize < BLOCK_32X32) {

     if (bsize < BLOCK_16X16)

       ctx->tx_rd_diff[ALLOW_16X16] = ctx->tx_rd_diff[ALLOW_8X8];

     ctx->tx_rd_diff[ALLOW_32X32] = ctx->tx_rd_diff[ALLOW_16X16];

   }

   if (is_inter_block(mbmi) && mbmi->sb_type < BLOCK_8X8) {

     mbmi->mv[0].as_int = mi->bmi[3].as_mv[0].as_int;

     mbmi->mv[1].as_int = mi->bmi[3].as_mv[1].as_int;

   }

   x->skip = ctx->skip;

   vpx_memcpy(x->zcoeff_blk[mbmi->tx_size], ctx->zcoeff_blk,

              sizeof(uint8_t) * ctx->num_4x4_blk);

   if (!output_enabled)

     return;

   if (!vp9_segfeature_active(&cm->seg, mbmi->segment_id, SEG_LVL_SKIP)) {

     for (i = 0; i < TX_MODES; i++)

       cpi->rd_tx_select_diff[i] += ctx->tx_rd_diff[i];

   }

   if (frame_is_intra_only(cm)) {

 #if CONFIG_INTERNAL_STATS

     static const int kf_mode_index[] = {

       THR_DC /*DC_PRED*/,

       THR_V_PRED /*V_PRED*/,

       THR_H_PRED /*H_PRED*/,

       THR_D45_PRED /*D45_PRED*/,

       THR_D135_PRED /*D135_PRED*/,

       THR_D117_PRED /*D117_PRED*/,

       THR_D153_PRED /*D153_PRED*/,

       THR_D207_PRED /*D207_PRED*/,

       THR_D63_PRED /*D63_PRED*/,

       THR_TM /*TM_PRED*/,

     };

     cpi->mode_chosen_counts[kf_mode_index[mi->mbmi.mode]]++;

 #endif

   } else {

     // Note how often each mode chosen as best

     cpi->mode_chosen_counts[mb_mode_index]++;

     if (is_inter_block(mbmi)

         && (mbmi->sb_type < BLOCK_8X8 || mbmi->mode == NEWMV)) {

       int_mv best_mv[2];

       const MV_REFERENCE_FRAME rf1 = mbmi->ref_frame[0];

       const MV_REFERENCE_FRAME rf2 = mbmi->ref_frame[1];

       best_mv[0].as_int = ctx->best_ref_mv.as_int;

       best_mv[1].as_int = ctx->second_best_ref_mv.as_int;

       if (mbmi->mode == NEWMV) {

         best_mv[0].as_int = mbmi->ref_mvs[rf1][0].as_int;

         if (rf2 > 0)

           best_mv[1].as_int = mbmi->ref_mvs[rf2][0].as_int;

       }

       mbmi->best_mv[0].as_int = best_mv[0].as_int;

       mbmi->best_mv[1].as_int = best_mv[1].as_int;

       vp9_update_mv_count(cpi, x, best_mv);

     }

     if (cm->mcomp_filter_type == SWITCHABLE && is_inter_mode(mbmi->mode)) {

       const int ctx = vp9_get_pred_context_switchable_interp(xd);

       ++cm->counts.switchable_interp[ctx][mbmi->interp_filter];

     }

     cpi->rd_comp_pred_diff[SINGLE_PREDICTION_ONLY] += ctx->single_pred_diff;

     cpi->rd_comp_pred_diff[COMP_PREDICTION_ONLY] += ctx->comp_pred_diff;

     cpi->rd_comp_pred_diff[HYBRID_PREDICTION] += ctx->hybrid_pred_diff;

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

       cpi->rd_filter_diff[i] += ctx->best_filter_diff[i];

   }

 }

 void vp9_setup_src_planes(MACROBLOCK *x, const YV12_BUFFER_CONFIG *src,

                           int mi_row, int mi_col) {

   uint8_t *const buffers[4] = {src->y_buffer, src->u_buffer, src->v_buffer,

                                src->alpha_buffer};

   const int strides[4] = {src->y_stride, src->uv_stride, src->uv_stride,

                           src->alpha_stride};

   int i;

   for (i = 0; i < MAX_MB_PLANE; i++)

     setup_pred_plane(&x->plane[i].src, buffers[i], strides[i], mi_row, mi_col,

                      NULL, x->e_mbd.plane[i].subsampling_x,

                      x->e_mbd.plane[i].subsampling_y);

 }

 static void set_offsets(VP9_COMP *cpi, const TileInfo *const tile,

                         int mi_row, int mi_col, BLOCK_SIZE bsize) {

   MACROBLOCK *const x = &cpi->mb;

   VP9_COMMON *const cm = &cpi->common;

   MACROBLOCKD *const xd = &x->e_mbd;

   MB_MODE_INFO *mbmi;

   const int dst_fb_idx = cm->new_fb_idx;

   const int idx_str = xd->mode_info_stride * mi_row + mi_col;

   const int mi_width = num_8x8_blocks_wide_lookup[bsize];

   const int mi_height = num_8x8_blocks_high_lookup[bsize];

   const int mb_row = mi_row >> 1;

   const int mb_col = mi_col >> 1;

   const int idx_map = mb_row * cm->mb_cols + mb_col;

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

   set_skip_context(xd, cpi->above_context, cpi->left_context, mi_row, mi_col);

   // Activity map pointer

   x->mb_activity_ptr = &cpi->mb_activity_map[idx_map];

   x->active_ptr = cpi->active_map + idx_map;

   xd->mi_8x8 = cm->mi_grid_visible + idx_str;

   xd->prev_mi_8x8 = cm->prev_mi_grid_visible + idx_str;

   // Special case: if prev_mi is NULL, the previous mode info context

   // cannot be used.

   xd->last_mi = cm->prev_mi ? xd->prev_mi_8x8[0] : NULL;

   xd->mi_8x8[0] = cm->mi + idx_str;

   mbmi = &xd->mi_8x8[0]->mbmi;

   // Set up destination pointers

   setup_dst_planes(xd, &cm->yv12_fb[dst_fb_idx], mi_row, mi_col);

   // Set up limit values for MV components

   // mv beyond the range do not produce new/different prediction block

   x->mv_row_min = -(((mi_row + mi_height) * MI_SIZE) + VP9_INTERP_EXTEND);

   x->mv_col_min = -(((mi_col + mi_width) * MI_SIZE) + VP9_INTERP_EXTEND);

   x->mv_row_max = (cm->mi_rows - mi_row) * MI_SIZE + VP9_INTERP_EXTEND;

   x->mv_col_max = (cm->mi_cols - mi_col) * MI_SIZE + VP9_INTERP_EXTEND;

   // Set up distance of MB to edge of frame in 1/8th pel units

   assert(!(mi_col & (mi_width - 1)) && !(mi_row & (mi_height - 1)));

   set_mi_row_col(xd, tile, mi_row, mi_height, mi_col, mi_width,

                  cm->mi_rows, cm->mi_cols);

   /* set up source buffers */

   vp9_setup_src_planes(x, cpi->Source, mi_row, mi_col);

   /* R/D setup */

   x->rddiv = cpi->RDDIV;

   x->rdmult = cpi->RDMULT;

   /* segment ID */

   if (seg->enabled) {

     if (!cpi->oxcf.aq_mode == VARIANCE_AQ) {

       uint8_t *map = seg->update_map ? cpi->segmentation_map

           : cm->last_frame_seg_map;

       mbmi->segment_id = vp9_get_segment_id(cm, map, bsize, mi_row, mi_col);

     }

     vp9_mb_init_quantizer(cpi, x);

     if (seg->enabled && cpi->seg0_cnt > 0

         && !vp9_segfeature_active(seg, 0, SEG_LVL_REF_FRAME)

         && vp9_segfeature_active(seg, 1, SEG_LVL_REF_FRAME)) {

       cpi->seg0_progress = (cpi->seg0_idx << 16) / cpi->seg0_cnt;

     } else {

       const int y = mb_row & ~3;

       const int x = mb_col & ~3;

       const int p16 = ((mb_row & 1) << 1) + (mb_col & 1);

       const int p32 = ((mb_row & 2) << 2) + ((mb_col & 2) << 1);

       const int tile_progress = tile->mi_col_start * cm->mb_rows >> 1;

       const int mb_cols = (tile->mi_col_end - tile->mi_col_start) >> 1;

       cpi->seg0_progress = ((y * mb_cols + x * 4 + p32 + p16 + tile_progress)

           << 16) / cm->MBs;

     }

     x->encode_breakout = cpi->segment_encode_breakout[mbmi->segment_id];

   } else {

     mbmi->segment_id = 0;

     x->encode_breakout = cpi->oxcf.encode_breakout;

   }

 }

 static void pick_sb_modes(VP9_COMP *cpi, const TileInfo *const tile,

                           int mi_row, int mi_col,

                           int *totalrate, int64_t *totaldist,

                           BLOCK_SIZE bsize, PICK_MODE_CONTEXT *ctx,

                           int64_t best_rd) {

   VP9_COMMON *const cm = &cpi->common;

   MACROBLOCK *const x = &cpi->mb;

   MACROBLOCKD *const xd = &x->e_mbd;

   struct macroblock_plane *const p = x->plane;

   struct macroblockd_plane *const pd = xd->plane;

   int i;

   int orig_rdmult = x->rdmult;

   double rdmult_ratio;

   vp9_clear_system_state();  // __asm emms;

   rdmult_ratio = 1.0;  // avoid uninitialized warnings

   // Use the lower precision, but faster, 32x32 fdct for mode selection.

   x->use_lp32x32fdct = 1;

   if (bsize < BLOCK_8X8) {

     // When ab_index = 0 all sub-blocks are handled, so for ab_index != 0

     // there is nothing to be done.

     if (x->ab_index != 0) {

       *totalrate = 0;

       *totaldist = 0;

       return;

     }

   }

   set_offsets(cpi, tile, mi_row, mi_col, bsize);

   xd->mi_8x8[0]->mbmi.sb_type = bsize;

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

     p[i].coeff = ctx->coeff_pbuf[i][0];

     pd[i].qcoeff = ctx->qcoeff_pbuf[i][0];

     pd[i].dqcoeff = ctx->dqcoeff_pbuf[i][0];

     pd[i].eobs = ctx->eobs_pbuf[i][0];

   }

   ctx->is_coded = 0;

   x->skip_recode = 0;

   // Set to zero to make sure we do not use the previous encoded frame stats

   xd->mi_8x8[0]->mbmi.skip_coeff = 0;

   x->source_variance = get_sby_perpixel_variance(cpi, x, bsize);

   if (cpi->oxcf.aq_mode == VARIANCE_AQ) {

     int energy;

     if (bsize <= BLOCK_16X16) {

       energy = x->mb_energy;

     } else {

       energy = vp9_block_energy(cpi, x, bsize);

     }

     xd->mi_8x8[0]->mbmi.segment_id = vp9_vaq_segment_id(energy);

     rdmult_ratio = vp9_vaq_rdmult_ratio(energy);

     vp9_mb_init_quantizer(cpi, x);

   }

   if (cpi->oxcf.tuning == VP8_TUNE_SSIM)

     vp9_activity_masking(cpi, x);

   if (cpi->oxcf.aq_mode == VARIANCE_AQ) {

     vp9_clear_system_state();  // __asm emms;

     x->rdmult = round(x->rdmult * rdmult_ratio);

   }

   // Find best coding mode & reconstruct the MB so it is available

   // as a predictor for MBs that follow in the SB

   if (frame_is_intra_only(cm)) {

     vp9_rd_pick_intra_mode_sb(cpi, x, totalrate, totaldist, bsize, ctx,

                               best_rd);

   } else {

     if (bsize >= BLOCK_8X8)

       vp9_rd_pick_inter_mode_sb(cpi, x, tile, mi_row, mi_col,

                                 totalrate, totaldist, bsize, ctx, best_rd);

     else

       vp9_rd_pick_inter_mode_sub8x8(cpi, x, tile, mi_row, mi_col, totalrate,

                                     totaldist, bsize, ctx, best_rd);

   }

   if (cpi->oxcf.aq_mode == VARIANCE_AQ) {

     x->rdmult = orig_rdmult;

     if (*totalrate != INT_MAX) {

       vp9_clear_system_state();  // __asm emms;

       *totalrate = round(*totalrate * rdmult_ratio);

     }

   }

 }

 static void update_stats(VP9_COMP *cpi) {

   VP9_COMMON *const cm = &cpi->common;

   MACROBLOCK *const x = &cpi->mb;

   MACROBLOCKD *const xd = &x->e_mbd;

   MODE_INFO *mi = xd->mi_8x8[0];

   MB_MODE_INFO *const mbmi = &mi->mbmi;

   if (!frame_is_intra_only(cm)) {

     const int seg_ref_active = vp9_segfeature_active(&cm->seg, mbmi->segment_id,

                                                      SEG_LVL_REF_FRAME);

     if (!seg_ref_active)

       cpi->intra_inter_count[vp9_get_pred_context_intra_inter(xd)]

                             [is_inter_block(mbmi)]++;

     // If the segment reference feature is enabled we have only a single

     // reference frame allowed for the segment so exclude it from

     // the reference frame counts used to work out probabilities.

     if (is_inter_block(mbmi) && !seg_ref_active) {

       if (cm->comp_pred_mode == HYBRID_PREDICTION)

         cpi->comp_inter_count[vp9_get_pred_context_comp_inter_inter(cm, xd)]

                              [has_second_ref(mbmi)]++;

       if (has_second_ref(mbmi)) {

         cpi->comp_ref_count[vp9_get_pred_context_comp_ref_p(cm, xd)]

                            [mbmi->ref_frame[0] == GOLDEN_FRAME]++;

       } else {

         cpi->single_ref_count[vp9_get_pred_context_single_ref_p1(xd)][0]

                              [mbmi->ref_frame[0] != LAST_FRAME]++;

         if (mbmi->ref_frame[0] != LAST_FRAME)

           cpi->single_ref_count[vp9_get_pred_context_single_ref_p2(xd)][1]

                                [mbmi->ref_frame[0] != GOLDEN_FRAME]++;

       }

     }

   }

 }

 static BLOCK_SIZE *get_sb_partitioning(MACROBLOCK *x, BLOCK_SIZE bsize) {

   switch (bsize) {

     case BLOCK_64X64:

       return &x->sb64_partitioning;

     case BLOCK_32X32:

       return &x->sb_partitioning[x->sb_index];

     case BLOCK_16X16:

       return &x->mb_partitioning[x->sb_index][x->mb_index];

     case BLOCK_8X8:

       return &x->b_partitioning[x->sb_index][x->mb_index][x->b_index];

     default:

       assert(0);

       return NULL;

   }

 }

 static void restore_context(VP9_COMP *cpi, int mi_row, int mi_col,

                             ENTROPY_CONTEXT a[16 * MAX_MB_PLANE],

                             ENTROPY_CONTEXT l[16 * MAX_MB_PLANE],

                             PARTITION_CONTEXT sa[8], PARTITION_CONTEXT sl[8],

                             BLOCK_SIZE bsize) {

   MACROBLOCK *const x = &cpi->mb;

   MACROBLOCKD *const xd = &x->e_mbd;

   int p;

   const int num_4x4_blocks_wide = num_4x4_blocks_wide_lookup[bsize];

   const int num_4x4_blocks_high = num_4x4_blocks_high_lookup[bsize];

   int mi_width = num_8x8_blocks_wide_lookup[bsize];

   int mi_height = num_8x8_blocks_high_lookup[bsize];

   for (p = 0; p < MAX_MB_PLANE; p++) {

     vpx_memcpy(

         cpi->above_context[p] + ((mi_col * 2) >> xd->plane[p].subsampling_x),

         a + num_4x4_blocks_wide * p,

         (sizeof(ENTROPY_CONTEXT) * num_4x4_blocks_wide) >>

         xd->plane[p].subsampling_x);

     vpx_memcpy(

         cpi->left_context[p]

             + ((mi_row & MI_MASK) * 2 >> xd->plane[p].subsampling_y),

         l + num_4x4_blocks_high * p,

         (sizeof(ENTROPY_CONTEXT) * num_4x4_blocks_high) >>

         xd->plane[p].subsampling_y);

   }

   vpx_memcpy(cpi->above_seg_context + mi_col, sa,

              sizeof(*cpi->above_seg_context) * mi_width);

   vpx_memcpy(cpi->left_seg_context + (mi_row & MI_MASK), sl,

              sizeof(cpi->left_seg_context[0]) * mi_height);

 }

 static void save_context(VP9_COMP *cpi, int mi_row, int mi_col,

                          ENTROPY_CONTEXT a[16 * MAX_MB_PLANE],

                          ENTROPY_CONTEXT l[16 * MAX_MB_PLANE],

                          PARTITION_CONTEXT sa[8], PARTITION_CONTEXT sl[8],

                          BLOCK_SIZE bsize) {

   const MACROBLOCK *const x = &cpi->mb;

   const MACROBLOCKD *const xd = &x->e_mbd;

   int p;

   const int num_4x4_blocks_wide = num_4x4_blocks_wide_lookup[bsize];

   const int num_4x4_blocks_high = num_4x4_blocks_high_lookup[bsize];

   int mi_width = num_8x8_blocks_wide_lookup[bsize];

   int mi_height = num_8x8_blocks_high_lookup[bsize];

   // buffer the above/left context information of the block in search.

   for (p = 0; p < MAX_MB_PLANE; ++p) {

     vpx_memcpy(

         a + num_4x4_blocks_wide * p,

         cpi->above_context[p] + (mi_col * 2 >> xd->plane[p].subsampling_x),

         (sizeof(ENTROPY_CONTEXT) * num_4x4_blocks_wide) >>

         xd->plane[p].subsampling_x);

     vpx_memcpy(

         l + num_4x4_blocks_high * p,

         cpi->left_context[p]

             + ((mi_row & MI_MASK) * 2 >> xd->plane[p].subsampling_y),

         (sizeof(ENTROPY_CONTEXT) * num_4x4_blocks_high) >>

         xd->plane[p].subsampling_y);

   }

   vpx_memcpy(sa, cpi->above_seg_context + mi_col,

              sizeof(*cpi->above_seg_context) * mi_width);

   vpx_memcpy(sl, cpi->left_seg_context + (mi_row & MI_MASK),

              sizeof(cpi->left_seg_context[0]) * mi_height);

 }

 static void encode_b(VP9_COMP *cpi, const TileInfo *const tile,

                      TOKENEXTRA **tp, int mi_row, int mi_col,

                      int output_enabled, BLOCK_SIZE bsize, int sub_index) {

   VP9_COMMON *const cm = &cpi->common;

   MACROBLOCK *const x = &cpi->mb;

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

     return;

   if (sub_index != -1)

     *get_sb_index(x, bsize) = sub_index;

   if (bsize < BLOCK_8X8) {

     // When ab_index = 0 all sub-blocks are handled, so for ab_index != 0

     // there is nothing to be done.

     if (x->ab_index > 0)

       return;

   }

   set_offsets(cpi, tile, mi_row, mi_col, bsize);

   update_state(cpi, get_block_context(x, bsize), bsize, output_enabled);

   encode_superblock(cpi, tp, output_enabled, mi_row, mi_col, bsize);

   if (output_enabled) {

     update_stats(cpi);

     (*tp)->token = EOSB_TOKEN;

     (*tp)++;

   }

 }

 static void encode_sb(VP9_COMP *cpi, const TileInfo *const tile,

                       TOKENEXTRA **tp, int mi_row, int mi_col,

                       int output_enabled, BLOCK_SIZE bsize) {

   VP9_COMMON *const cm = &cpi->common;

   MACROBLOCK *const x = &cpi->mb;

   BLOCK_SIZE c1 = BLOCK_8X8;

   const int bsl = b_width_log2(bsize), bs = (1 << bsl) / 4;

   int pl = 0;

   PARTITION_TYPE partition;

   BLOCK_SIZE subsize;

   int i;

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

     return;

   c1 = BLOCK_4X4;

   if (bsize >= BLOCK_8X8) {

     pl = partition_plane_context(cpi->above_seg_context, cpi->left_seg_context,

                                  mi_row, mi_col, bsize);

     c1 = *(get_sb_partitioning(x, bsize));

   }

   partition = partition_lookup[bsl][c1];

   switch (partition) {

     case PARTITION_NONE:

       if (output_enabled && bsize >= BLOCK_8X8)

         cpi->partition_count[pl][PARTITION_NONE]++;

       encode_b(cpi, tile, tp, mi_row, mi_col, output_enabled, c1, -1);

       break;

     case PARTITION_VERT:

       if (output_enabled)

         cpi->partition_count[pl][PARTITION_VERT]++;

       encode_b(cpi, tile, tp, mi_row, mi_col, output_enabled, c1, 0);

       encode_b(cpi, tile, tp, mi_row, mi_col + bs, output_enabled, c1, 1);

       break;

     case PARTITION_HORZ:

       if (output_enabled)

         cpi->partition_count[pl][PARTITION_HORZ]++;

       encode_b(cpi, tile, tp, mi_row, mi_col, output_enabled, c1, 0);

       encode_b(cpi, tile, tp, mi_row + bs, mi_col, output_enabled, c1, 1);

       break;

     case PARTITION_SPLIT:

       subsize = get_subsize(bsize, PARTITION_SPLIT);

       if (output_enabled)

         cpi->partition_count[pl][PARTITION_SPLIT]++;

       for (i = 0; i < 4; i++) {

         const int x_idx = i & 1, y_idx = i >> 1;

         *get_sb_index(x, subsize) = i;

         encode_sb(cpi, tile, tp, mi_row + y_idx * bs, mi_col + x_idx * bs,

                   output_enabled, subsize);

       }

       break;

     default:

       assert(0);

       break;

   }

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

     update_partition_context(cpi->above_seg_context, cpi->left_seg_context,

                              mi_row, mi_col, c1, bsize);

 }

 // Check to see if the given partition size is allowed for a specified number

 // of 8x8 block rows and columns remaining in the image.

 // If not then return the largest allowed partition size

 static BLOCK_SIZE find_partition_size(BLOCK_SIZE bsize,

                                       int rows_left, int cols_left,

                                       int *bh, int *bw) {

   if ((rows_left <= 0) || (cols_left <= 0)) {

     return MIN(bsize, BLOCK_8X8);

   } else {

     for (; bsize > 0; --bsize) {

       *bh = num_8x8_blocks_high_lookup[bsize];

       *bw = num_8x8_blocks_wide_lookup[bsize];

       if ((*bh <= rows_left) && (*bw <= cols_left)) {

         break;

       }

     }

   }

   return bsize;

 }

 // This function attempts to set all mode info entries in a given SB64

 // to the same block partition size.

 // However, at the bottom and right borders of the image the requested size

 // may not be allowed in which case this code attempts to choose the largest

 // allowable partition.

 static void set_partitioning(VP9_COMP *cpi, const TileInfo *const tile,

                              MODE_INFO **mi_8x8, int mi_row, int mi_col) {

   VP9_COMMON *const cm = &cpi->common;

   BLOCK_SIZE bsize = cpi->sf.always_this_block_size;

   const int mis = cm->mode_info_stride;

   int row8x8_remaining = tile->mi_row_end - mi_row;

   int col8x8_remaining = tile->mi_col_end - mi_col;

   int block_row, block_col;

   MODE_INFO * mi_upper_left = cm->mi + mi_row * mis + mi_col;

   int bh = num_8x8_blocks_high_lookup[bsize];

   int bw = num_8x8_blocks_wide_lookup[bsize];

   assert((row8x8_remaining > 0) && (col8x8_remaining > 0));

   // Apply the requested partition size to the SB64 if it is all "in image"

   if ((col8x8_remaining >= MI_BLOCK_SIZE) &&

       (row8x8_remaining >= MI_BLOCK_SIZE)) {

     for (block_row = 0; block_row < MI_BLOCK_SIZE; block_row += bh) {

       for (block_col = 0; block_col < MI_BLOCK_SIZE; block_col += bw) {

         int index = block_row * mis + block_col;

         mi_8x8[index] = mi_upper_left + index;

         mi_8x8[index]->mbmi.sb_type = bsize;

       }

     }

   } else {

     // Else this is a partial SB64.

     for (block_row = 0; block_row < MI_BLOCK_SIZE; block_row += bh) {

       for (block_col = 0; block_col < MI_BLOCK_SIZE; block_col += bw) {

         int index = block_row * mis + block_col;

         // Find a partition size that fits

         bsize = find_partition_size(cpi->sf.always_this_block_size,

                                     (row8x8_remaining - block_row),

                                     (col8x8_remaining - block_col), &bh, &bw);

         mi_8x8[index] = mi_upper_left + index;

         mi_8x8[index]->mbmi.sb_type = bsize;

       }

     }

   }

 }

 static void copy_partitioning(VP9_COMP *cpi, MODE_INFO **mi_8x8,

                               MODE_INFO **prev_mi_8x8) {

   VP9_COMMON *const cm = &cpi->common;

   const int mis = cm->mode_info_stride;

   int block_row, block_col;

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

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

       MODE_INFO * prev_mi = prev_mi_8x8[block_row * mis + block_col];

       BLOCK_SIZE sb_type = prev_mi ? prev_mi->mbmi.sb_type : 0;

       ptrdiff_t offset;

       if (prev_mi) {

         offset = prev_mi - cm->prev_mi;

         mi_8x8[block_row * mis + block_col] = cm->mi + offset;

         mi_8x8[block_row * mis + block_col]->mbmi.sb_type = sb_type;

       }

     }

   }

 }

 static int sb_has_motion(VP9_COMP *cpi, MODE_INFO **prev_mi_8x8) {

   VP9_COMMON *const cm = &cpi->common;

   const int mis = cm->mode_info_stride;

   int block_row, block_col;

   if (cm->prev_mi) {

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

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

         MODE_INFO * prev_mi = prev_mi_8x8[block_row * mis + block_col];

         if (prev_mi) {

           if (abs(prev_mi->mbmi.mv[0].as_mv.row) >= 8 ||

               abs(prev_mi->mbmi.mv[0].as_mv.col) >= 8)

             return 1;

         }

       }

     }

   }

   return 0;

 }

 static void rd_use_partition(VP9_COMP *cpi,

                              const TileInfo *const tile,

                              MODE_INFO **mi_8x8,

                              TOKENEXTRA **tp, int mi_row, int mi_col,

                              BLOCK_SIZE bsize, int *rate, int64_t *dist,

                              int do_recon) {

   VP9_COMMON *const cm = &cpi->common;

   MACROBLOCK *const x = &cpi->mb;

   const int mis = cm->mode_info_stride;

   int bsl = b_width_log2(bsize);

   const int num_4x4_blocks_wide = num_4x4_blocks_wide_lookup[bsize];

   const int num_4x4_blocks_high = num_4x4_blocks_high_lookup[bsize];

   int ms = num_4x4_blocks_wide / 2;

   int mh = num_4x4_blocks_high / 2;

   int bss = (1 << bsl) / 4;

   int i, pl;

   PARTITION_TYPE partition = PARTITION_NONE;

   BLOCK_SIZE subsize;

   ENTROPY_CONTEXT l[16 * MAX_MB_PLANE], a[16 * MAX_MB_PLANE];

   PARTITION_CONTEXT sl[8], sa[8];

   int last_part_rate = INT_MAX;

   int64_t last_part_dist = INT_MAX;

   int split_rate = INT_MAX;

   int64_t split_dist = INT_MAX;

   int none_rate = INT_MAX;

   int64_t none_dist = INT_MAX;

   int chosen_rate = INT_MAX;

   int64_t chosen_dist = INT_MAX;

   BLOCK_SIZE sub_subsize = BLOCK_4X4;

   int splits_below = 0;

   BLOCK_SIZE bs_type = mi_8x8[0]->mbmi.sb_type;

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

     return;

   partition = partition_lookup[bsl][bs_type];

   subsize = get_subsize(bsize, partition);

   if (bsize < BLOCK_8X8) {

     // When ab_index = 0 all sub-blocks are handled, so for ab_index != 0

     // there is nothing to be done.

     if (x->ab_index != 0) {

       *rate = 0;

       *dist = 0;

       return;

     }

   } else {

     *(get_sb_partitioning(x, bsize)) = subsize;

   }

   save_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

   if (bsize == BLOCK_16X16) {

     set_offsets(cpi, tile, mi_row, mi_col, bsize);

     x->mb_energy = vp9_block_energy(cpi, x, bsize);

   }

   x->fast_ms = 0;

   x->subblock_ref = 0;

   if (cpi->sf.adjust_partitioning_from_last_frame) {

     // Check if any of the sub blocks are further split.

     if (partition == PARTITION_SPLIT && subsize > BLOCK_8X8) {

       sub_subsize = get_subsize(subsize, PARTITION_SPLIT);

       splits_below = 1;

       for (i = 0; i < 4; i++) {

         int jj = i >> 1, ii = i & 0x01;

         MODE_INFO * this_mi = mi_8x8[jj * bss * mis + ii * bss];

         if (this_mi && this_mi->mbmi.sb_type >= sub_subsize) {

           splits_below = 0;

         }

       }

     }

     // If partition is not none try none unless each of the 4 splits are split

     // even further..

     if (partition != PARTITION_NONE && !splits_below &&

         mi_row + (ms >> 1) < cm->mi_rows &&

         mi_col + (ms >> 1) < cm->mi_cols) {

       *(get_sb_partitioning(x, bsize)) = bsize;

       pick_sb_modes(cpi, tile, mi_row, mi_col, &none_rate, &none_dist, bsize,

                     get_block_context(x, bsize), INT64_MAX);

       pl = partition_plane_context(cpi->above_seg_context,

                                    cpi->left_seg_context,

                                    mi_row, mi_col, bsize);

       none_rate += x->partition_cost[pl][PARTITION_NONE];

       restore_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

       mi_8x8[0]->mbmi.sb_type = bs_type;

       *(get_sb_partitioning(x, bsize)) = subsize;

     }

   }

   switch (partition) {

     case PARTITION_NONE:

       pick_sb_modes(cpi, tile, mi_row, mi_col, &last_part_rate, &last_part_dist,

                     bsize, get_block_context(x, bsize), INT64_MAX);

       break;

     case PARTITION_HORZ:

       *get_sb_index(x, subsize) = 0;

       pick_sb_modes(cpi, tile, mi_row, mi_col, &last_part_rate, &last_part_dist,

                     subsize, get_block_context(x, subsize), INT64_MAX);

       if (last_part_rate != INT_MAX &&

           bsize >= BLOCK_8X8 && mi_row + (mh >> 1) < cm->mi_rows) {

         int rt = 0;

         int64_t dt = 0;

         update_state(cpi, get_block_context(x, subsize), subsize, 0);

         encode_superblock(cpi, tp, 0, mi_row, mi_col, subsize);

         *get_sb_index(x, subsize) = 1;

         pick_sb_modes(cpi, tile, mi_row + (ms >> 1), mi_col, &rt, &dt, subsize,

                       get_block_context(x, subsize), INT64_MAX);

         if (rt == INT_MAX || dt == INT_MAX) {

           last_part_rate = INT_MAX;

           last_part_dist = INT_MAX;

           break;

         }

         last_part_rate += rt;

         last_part_dist += dt;

       }

       break;

     case PARTITION_VERT:

       *get_sb_index(x, subsize) = 0;

       pick_sb_modes(cpi, tile, mi_row, mi_col, &last_part_rate, &last_part_dist,

                     subsize, get_block_context(x, subsize), INT64_MAX);

       if (last_part_rate != INT_MAX &&

           bsize >= BLOCK_8X8 && mi_col + (ms >> 1) < cm->mi_cols) {

         int rt = 0;

         int64_t dt = 0;

         update_state(cpi, get_block_context(x, subsize), subsize, 0);

         encode_superblock(cpi, tp, 0, mi_row, mi_col, subsize);

         *get_sb_index(x, subsize) = 1;

         pick_sb_modes(cpi, tile, mi_row, mi_col + (ms >> 1), &rt, &dt, subsize,

                       get_block_context(x, subsize), INT64_MAX);

         if (rt == INT_MAX || dt == INT_MAX) {

           last_part_rate = INT_MAX;

           last_part_dist = INT_MAX;

           break;

         }

         last_part_rate += rt;

         last_part_dist += dt;

       }

       break;

     case PARTITION_SPLIT:

       // Split partition.

       last_part_rate = 0;

       last_part_dist = 0;

       for (i = 0; i < 4; i++) {

         int x_idx = (i & 1) * (ms >> 1);

         int y_idx = (i >> 1) * (ms >> 1);

         int jj = i >> 1, ii = i & 0x01;

         int rt;

         int64_t dt;

         if ((mi_row + y_idx >= cm->mi_rows) || (mi_col + x_idx >= cm->mi_cols))

           continue;

         *get_sb_index(x, subsize) = i;

         rd_use_partition(cpi, tile, mi_8x8 + jj * bss * mis + ii * bss, tp,

                          mi_row + y_idx, mi_col + x_idx, subsize, &rt, &dt,

                          i != 3);

         if (rt == INT_MAX || dt == INT_MAX) {

           last_part_rate = INT_MAX;

           last_part_dist = INT_MAX;

           break;

         }

         last_part_rate += rt;

         last_part_dist += dt;

       }

       break;

     default:

       assert(0);

   }

   pl = partition_plane_context(cpi->above_seg_context, cpi->left_seg_context,

                                mi_row, mi_col, bsize);

   if (last_part_rate < INT_MAX)

     last_part_rate += x->partition_cost[pl][partition];

   if (cpi->sf.adjust_partitioning_from_last_frame

       && partition != PARTITION_SPLIT && bsize > BLOCK_8X8

       && (mi_row + ms < cm->mi_rows || mi_row + (ms >> 1) == cm->mi_rows)

       && (mi_col + ms < cm->mi_cols || mi_col + (ms >> 1) == cm->mi_cols)) {

     BLOCK_SIZE split_subsize = get_subsize(bsize, PARTITION_SPLIT);

     split_rate = 0;

     split_dist = 0;

     restore_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

     // Split partition.

     for (i = 0; i < 4; i++) {

       int x_idx = (i & 1) * (num_4x4_blocks_wide >> 2);

       int y_idx = (i >> 1) * (num_4x4_blocks_wide >> 2);

       int rt = 0;

       int64_t dt = 0;

       ENTROPY_CONTEXT l[16 * MAX_MB_PLANE], a[16 * MAX_MB_PLANE];

       PARTITION_CONTEXT sl[8], sa[8];

       if ((mi_row + y_idx >= cm->mi_rows) || (mi_col + x_idx >= cm->mi_cols))

         continue;

       *get_sb_index(x, split_subsize) = i;

       *get_sb_partitioning(x, bsize) = split_subsize;

       *get_sb_partitioning(x, split_subsize) = split_subsize;

       save_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

       pick_sb_modes(cpi, tile, mi_row + y_idx, mi_col + x_idx, &rt, &dt,

                     split_subsize, get_block_context(x, split_subsize),

                     INT64_MAX);

       restore_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

       if (rt == INT_MAX || dt == INT_MAX) {

         split_rate = INT_MAX;

         split_dist = INT_MAX;

         break;

       }

       if (i != 3)

         encode_sb(cpi, tile, tp,  mi_row + y_idx, mi_col + x_idx, 0,

                   split_subsize);

       split_rate += rt;

       split_dist += dt;

       pl = partition_plane_context(cpi->above_seg_context,

                                    cpi->left_seg_context,

                                    mi_row + y_idx, mi_col + x_idx, bsize);

       split_rate += x->partition_cost[pl][PARTITION_NONE];

     }

     pl = partition_plane_context(cpi->above_seg_context, cpi->left_seg_context,

                                  mi_row, mi_col, bsize);

     if (split_rate < INT_MAX) {

       split_rate += x->partition_cost[pl][PARTITION_SPLIT];

       chosen_rate = split_rate;

       chosen_dist = split_dist;

     }

   }

   // If last_part is better set the partitioning to that...

   if (RDCOST(x->rdmult, x->rddiv, last_part_rate, last_part_dist)

       < RDCOST(x->rdmult, x->rddiv, chosen_rate, chosen_dist)) {

     mi_8x8[0]->mbmi.sb_type = bsize;

     if (bsize >= BLOCK_8X8)

       *(get_sb_partitioning(x, bsize)) = subsize;

     chosen_rate = last_part_rate;

     chosen_dist = last_part_dist;

   }

   // If none was better set the partitioning to that...

   if (RDCOST(x->rdmult, x->rddiv, chosen_rate, chosen_dist)

       > RDCOST(x->rdmult, x->rddiv, none_rate, none_dist)) {

     if (bsize >= BLOCK_8X8)

       *(get_sb_partitioning(x, bsize)) = bsize;

     chosen_rate = none_rate;

     chosen_dist = none_dist;

   }

   restore_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

   // We must have chosen a partitioning and encoding or we'll fail later on.

   // No other opportunities for success.

   if ( bsize == BLOCK_64X64)

     assert(chosen_rate < INT_MAX && chosen_dist < INT_MAX);

   if (do_recon)

     encode_sb(cpi, tile, tp, mi_row, mi_col, bsize == BLOCK_64X64, bsize);

   *rate = chosen_rate;

   *dist = chosen_dist;

 }

 static const BLOCK_SIZE min_partition_size[BLOCK_SIZES] = {

   BLOCK_4X4, BLOCK_4X4, BLOCK_4X4, BLOCK_4X4,

   BLOCK_4X4, BLOCK_4X4, BLOCK_8X8, BLOCK_8X8,

   BLOCK_8X8, BLOCK_16X16, BLOCK_16X16, BLOCK_16X16, BLOCK_16X16

 };

 static const BLOCK_SIZE max_partition_size[BLOCK_SIZES] = {

   BLOCK_8X8, BLOCK_16X16, BLOCK_16X16, BLOCK_16X16,

   BLOCK_32X32, BLOCK_32X32, BLOCK_32X32, BLOCK_64X64,

   BLOCK_64X64, BLOCK_64X64, BLOCK_64X64, BLOCK_64X64, BLOCK_64X64

 };

 // Look at all the mode_info entries for blocks that are part of this

 // partition and find the min and max values for sb_type.

 // At the moment this is designed to work on a 64x64 SB but could be

 // adjusted to use a size parameter.

 //

 // The min and max are assumed to have been initialized prior to calling this

 // function so repeat calls can accumulate a min and max of more than one sb64.

 static void get_sb_partition_size_range(VP9_COMP *cpi, MODE_INFO ** mi_8x8,

                                         BLOCK_SIZE * min_block_size,

                                         BLOCK_SIZE * max_block_size ) {

   MACROBLOCKD *const xd = &cpi->mb.e_mbd;

   int sb_width_in_blocks = MI_BLOCK_SIZE;

   int sb_height_in_blocks  = MI_BLOCK_SIZE;

   int i, j;

   int index = 0;

   // Check the sb_type for each block that belongs to this region.

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

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

       MODE_INFO * mi = mi_8x8[index+j];

       BLOCK_SIZE sb_type = mi ? mi->mbmi.sb_type : 0;

       *min_block_size = MIN(*min_block_size, sb_type);

       *max_block_size = MAX(*max_block_size, sb_type);

     }

     index += xd->mode_info_stride;

   }

 }

 // Look at neighboring blocks and set a min and max partition size based on

 // what they chose.

 static void rd_auto_partition_range(VP9_COMP *cpi, const TileInfo *const tile,

                                     int row, int col,

                                     BLOCK_SIZE *min_block_size,

                                     BLOCK_SIZE *max_block_size) {

   VP9_COMMON * const cm = &cpi->common;

   MACROBLOCKD *const xd = &cpi->mb.e_mbd;

   MODE_INFO ** mi_8x8 = xd->mi_8x8;

   MODE_INFO ** prev_mi_8x8 = xd->prev_mi_8x8;

   const int left_in_image = xd->left_available && mi_8x8[-1];

   const int above_in_image = xd->up_available &&

                              mi_8x8[-xd->mode_info_stride];

   MODE_INFO ** above_sb64_mi_8x8;

   MODE_INFO ** left_sb64_mi_8x8;

   int row8x8_remaining = tile->mi_row_end - row;

   int col8x8_remaining = tile->mi_col_end - col;

   int bh, bw;

   // Trap case where we do not have a prediction.

   if (!left_in_image && !above_in_image &&

       ((cm->frame_type == KEY_FRAME) || !cm->prev_mi)) {

     *min_block_size = BLOCK_4X4;

     *max_block_size = BLOCK_64X64;

   } else {

     // Default "min to max" and "max to min"

     *min_block_size = BLOCK_64X64;

     *max_block_size = BLOCK_4X4;

     // NOTE: each call to get_sb_partition_size_range() uses the previous

     // passed in values for min and max as a starting point.

     //

     // Find the min and max partition used in previous frame at this location

     if (cm->prev_mi && (cm->frame_type != KEY_FRAME)) {

       get_sb_partition_size_range(cpi, prev_mi_8x8,

                                   min_block_size, max_block_size);

     }

     // Find the min and max partition sizes used in the left SB64

     if (left_in_image) {

       left_sb64_mi_8x8 = &mi_8x8[-MI_BLOCK_SIZE];

       get_sb_partition_size_range(cpi, left_sb64_mi_8x8,

                                   min_block_size, max_block_size);

     }

     // Find the min and max partition sizes used in the above SB64.

     if (above_in_image) {

       above_sb64_mi_8x8 = &mi_8x8[-xd->mode_info_stride * MI_BLOCK_SIZE];

       get_sb_partition_size_range(cpi, above_sb64_mi_8x8,

                                   min_block_size, max_block_size);

     }

   }

   // Give a bit of leaway either side of the observed min and max

   *min_block_size = min_partition_size[*min_block_size];

   *max_block_size = max_partition_size[*max_block_size];

   // Check border cases where max and min from neighbours may not be legal.

   *max_block_size = find_partition_size(*max_block_size,

                                         row8x8_remaining, col8x8_remaining,

                                         &bh, &bw);

   *min_block_size = MIN(*min_block_size, *max_block_size);

 }

 static void compute_fast_motion_search_level(VP9_COMP *cpi, BLOCK_SIZE bsize) {

   VP9_COMMON *const cm = &cpi->common;

   MACROBLOCK *const x = &cpi->mb;

   // Only use 8x8 result for non HD videos.

   // int use_8x8 = (MIN(cpi->common.width, cpi->common.height) < 720) ? 1 : 0;

   int use_8x8 = 1;

   if (cm->frame_type && !cpi->is_src_frame_alt_ref &&

       ((use_8x8 && bsize == BLOCK_16X16) ||

       bsize == BLOCK_32X32 || bsize == BLOCK_64X64)) {

     int ref0 = 0, ref1 = 0, ref2 = 0, ref3 = 0;

     PICK_MODE_CONTEXT *block_context = NULL;

     if (bsize == BLOCK_16X16) {

       block_context = x->sb8x8_context[x->sb_index][x->mb_index];

     } else if (bsize == BLOCK_32X32) {

       block_context = x->mb_context[x->sb_index];

     } else if (bsize == BLOCK_64X64) {

       block_context = x->sb32_context;

     }

     if (block_context) {

       ref0 = block_context[0].mic.mbmi.ref_frame[0];

       ref1 = block_context[1].mic.mbmi.ref_frame[0];

       ref2 = block_context[2].mic.mbmi.ref_frame[0];

       ref3 = block_context[3].mic.mbmi.ref_frame[0];

     }

     // Currently, only consider 4 inter reference frames.

     if (ref0 && ref1 && ref2 && ref3) {

       int d01, d23, d02, d13;

       // Motion vectors for the four subblocks.

       int16_t mvr0 = block_context[0].mic.mbmi.mv[0].as_mv.row;

       int16_t mvc0 = block_context[0].mic.mbmi.mv[0].as_mv.col;

       int16_t mvr1 = block_context[1].mic.mbmi.mv[0].as_mv.row;

       int16_t mvc1 = block_context[1].mic.mbmi.mv[0].as_mv.col;

       int16_t mvr2 = block_context[2].mic.mbmi.mv[0].as_mv.row;

       int16_t mvc2 = block_context[2].mic.mbmi.mv[0].as_mv.col;

       int16_t mvr3 = block_context[3].mic.mbmi.mv[0].as_mv.row;

       int16_t mvc3 = block_context[3].mic.mbmi.mv[0].as_mv.col;

       // Adjust sign if ref is alt_ref.

       if (cm->ref_frame_sign_bias[ref0]) {

         mvr0 *= -1;

         mvc0 *= -1;

       }

       if (cm->ref_frame_sign_bias[ref1]) {

         mvr1 *= -1;

         mvc1 *= -1;

       }

       if (cm->ref_frame_sign_bias[ref2]) {

         mvr2 *= -1;

         mvc2 *= -1;

       }

       if (cm->ref_frame_sign_bias[ref3]) {

         mvr3 *= -1;

         mvc3 *= -1;

       }

       // Calculate mv distances.

       d01 = MAX(abs(mvr0 - mvr1), abs(mvc0 - mvc1));

       d23 = MAX(abs(mvr2 - mvr3), abs(mvc2 - mvc3));

       d02 = MAX(abs(mvr0 - mvr2), abs(mvc0 - mvc2));

       d13 = MAX(abs(mvr1 - mvr3), abs(mvc1 - mvc3));

       if (d01 < FAST_MOTION_MV_THRESH && d23 < FAST_MOTION_MV_THRESH &&

           d02 < FAST_MOTION_MV_THRESH && d13 < FAST_MOTION_MV_THRESH) {

         // Set fast motion search level.

         x->fast_ms = 1;

         if (ref0 == ref1 && ref1 == ref2 && ref2 == ref3 &&

             d01 < 2 && d23 < 2 && d02 < 2 && d13 < 2) {

           // Set fast motion search level.

           x->fast_ms = 2;

           if (!d01 && !d23 && !d02 && !d13) {

             x->fast_ms = 3;

             x->subblock_ref = ref0;

           }

         }

       }

     }

   }

 }

 static INLINE void store_pred_mv(MACROBLOCK *x, PICK_MODE_CONTEXT *ctx) {

   vpx_memcpy(ctx->pred_mv, x->pred_mv, sizeof(x->pred_mv));

 }

 static INLINE void load_pred_mv(MACROBLOCK *x, PICK_MODE_CONTEXT *ctx) {

   vpx_memcpy(x->pred_mv, ctx->pred_mv, sizeof(x->pred_mv));

 }

 // TODO(jingning,jimbankoski,rbultje): properly skip partition types that are

 // unlikely to be selected depending on previous rate-distortion optimization

 // results, for encoding speed-up.

 static void rd_pick_partition(VP9_COMP *cpi, const TileInfo *const tile,

                               TOKENEXTRA **tp, int mi_row,

                               int mi_col, BLOCK_SIZE bsize, int *rate,

                               int64_t *dist, int do_recon, int64_t best_rd) {

   VP9_COMMON *const cm = &cpi->common;

   MACROBLOCK *const x = &cpi->mb;

   const int ms = num_8x8_blocks_wide_lookup[bsize] / 2;

   ENTROPY_CONTEXT l[16 * MAX_MB_PLANE], a[16 * MAX_MB_PLANE];

   PARTITION_CONTEXT sl[8], sa[8];

   TOKENEXTRA *tp_orig = *tp;

   int i, pl;

   BLOCK_SIZE subsize;

   int this_rate, sum_rate = 0, best_rate = INT_MAX;

   int64_t this_dist, sum_dist = 0, best_dist = INT64_MAX;

   int64_t sum_rd = 0;

   int do_split = bsize >= BLOCK_8X8;

   int do_rect = 1;

   // Override skipping rectangular partition operations for edge blocks

   const int force_horz_split = (mi_row + ms >= cm->mi_rows);

   const int force_vert_split = (mi_col + ms >= cm->mi_cols);

   int partition_none_allowed = !force_horz_split && !force_vert_split;

   int partition_horz_allowed = !force_vert_split && bsize >= BLOCK_8X8;

   int partition_vert_allowed = !force_horz_split && bsize >= BLOCK_8X8;

   int partition_split_done = 0;

   (void) *tp_orig;

   if (bsize < BLOCK_8X8) {

     // When ab_index = 0 all sub-blocks are handled, so for ab_index != 0

     // there is nothing to be done.

     if (x->ab_index != 0) {

       *rate = 0;

       *dist = 0;

       return;

     }

   }

   assert(num_8x8_blocks_wide_lookup[bsize] ==

              num_8x8_blocks_high_lookup[bsize]);

   if (bsize == BLOCK_16X16) {

     set_offsets(cpi, tile, mi_row, mi_col, bsize);

     x->mb_energy = vp9_block_energy(cpi, x, bsize);

   }

   // Determine partition types in search according to the speed features.

   // The threshold set here has to be of square block size.

   if (cpi->sf.auto_min_max_partition_size) {

     partition_none_allowed &= (bsize <= cpi->sf.max_partition_size &&

                                bsize >= cpi->sf.min_partition_size);

     partition_horz_allowed &= ((bsize <= cpi->sf.max_partition_size &&

                                 bsize >  cpi->sf.min_partition_size) ||

                                 force_horz_split);

     partition_vert_allowed &= ((bsize <= cpi->sf.max_partition_size &&

                                 bsize >  cpi->sf.min_partition_size) ||

                                 force_vert_split);

     do_split &= bsize > cpi->sf.min_partition_size;

   }

   if (cpi->sf.use_square_partition_only) {

     partition_horz_allowed &= force_horz_split;

     partition_vert_allowed &= force_vert_split;

   }

   save_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

   if (cpi->sf.disable_split_var_thresh && partition_none_allowed) {

     unsigned int source_variancey;

     vp9_setup_src_planes(x, cpi->Source, mi_row, mi_col);

     source_variancey = get_sby_perpixel_variance(cpi, x, bsize);

     if (source_variancey < cpi->sf.disable_split_var_thresh) {

       do_split = 0;

       if (source_variancey < cpi->sf.disable_split_var_thresh / 2)

         do_rect = 0;

     }

   }

   // PARTITION_NONE

   if (partition_none_allowed) {

     pick_sb_modes(cpi, tile, mi_row, mi_col, &this_rate, &this_dist, bsize,

                   get_block_context(x, bsize), best_rd);

     if (this_rate != INT_MAX) {

       if (bsize >= BLOCK_8X8) {

         pl = partition_plane_context(cpi->above_seg_context,

                                      cpi->left_seg_context,

                                      mi_row, mi_col, bsize);

         this_rate += x->partition_cost[pl][PARTITION_NONE];

       }

       sum_rd = RDCOST(x->rdmult, x->rddiv, this_rate, this_dist);

       if (sum_rd < best_rd) {

         int64_t stop_thresh = 2048;

         best_rate = this_rate;

         best_dist = this_dist;

         best_rd = sum_rd;

         if (bsize >= BLOCK_8X8)

           *(get_sb_partitioning(x, bsize)) = bsize;

         // Adjust threshold according to partition size.

         stop_thresh >>= 8 - (b_width_log2_lookup[bsize] +

             b_height_log2_lookup[bsize]);

         // If obtained distortion is very small, choose current partition

         // and stop splitting.

         if (this_dist < stop_thresh) {

           do_split = 0;

           do_rect = 0;

         }

       }

     }

     restore_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

   }

   // store estimated motion vector

   if (cpi->sf.adaptive_motion_search)

     store_pred_mv(x, get_block_context(x, bsize));

   // PARTITION_SPLIT

   sum_rd = 0;

   // TODO(jingning): use the motion vectors given by the above search as

   // the starting point of motion search in the following partition type check.

   if (do_split) {

     subsize = get_subsize(bsize, PARTITION_SPLIT);

     for (i = 0; i < 4 && sum_rd < best_rd; ++i) {

       const int x_idx = (i & 1) * ms;

       const int y_idx = (i >> 1) * ms;

       if (mi_row + y_idx >= cm->mi_rows || mi_col + x_idx >= cm->mi_cols)

         continue;

       *get_sb_index(x, subsize) = i;

       if (cpi->sf.adaptive_motion_search)

         load_pred_mv(x, get_block_context(x, bsize));

       rd_pick_partition(cpi, tile, tp, mi_row + y_idx, mi_col + x_idx, subsize,

                         &this_rate, &this_dist, i != 3, best_rd - sum_rd);

       if (this_rate == INT_MAX) {

         sum_rd = INT64_MAX;

       } else {

         sum_rate += this_rate;

         sum_dist += this_dist;

         sum_rd = RDCOST(x->rdmult, x->rddiv, sum_rate, sum_dist);

       }

     }

     if (sum_rd < best_rd && i == 4) {

       pl = partition_plane_context(cpi->above_seg_context,

                                    cpi->left_seg_context,

                                    mi_row, mi_col, bsize);

       sum_rate += x->partition_cost[pl][PARTITION_SPLIT];

       sum_rd = RDCOST(x->rdmult, x->rddiv, sum_rate, sum_dist);

       if (sum_rd < best_rd) {

         best_rate = sum_rate;

         best_dist = sum_dist;

         best_rd = sum_rd;

         *(get_sb_partitioning(x, bsize)) = subsize;

       }

     } else {

       // skip rectangular partition test when larger block size

       // gives better rd cost

       if (cpi->sf.less_rectangular_check)

         do_rect &= !partition_none_allowed;

     }

     partition_split_done = 1;

     restore_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

   }

   x->fast_ms = 0;

   x->subblock_ref = 0;

   if (partition_split_done &&

       cpi->sf.using_small_partition_info) {

     compute_fast_motion_search_level(cpi, bsize);

   }

   // PARTITION_HORZ

   if (partition_horz_allowed && do_rect) {

     subsize = get_subsize(bsize, PARTITION_HORZ);

     *get_sb_index(x, subsize) = 0;

     if (cpi->sf.adaptive_motion_search)

       load_pred_mv(x, get_block_context(x, bsize));

     pick_sb_modes(cpi, tile, mi_row, mi_col, &sum_rate, &sum_dist, subsize,

                   get_block_context(x, subsize), best_rd);

     sum_rd = RDCOST(x->rdmult, x->rddiv, sum_rate, sum_dist);

     if (sum_rd < best_rd && mi_row + ms < cm->mi_rows) {

       update_state(cpi, get_block_context(x, subsize), subsize, 0);

       encode_superblock(cpi, tp, 0, mi_row, mi_col, subsize);

       *get_sb_index(x, subsize) = 1;

       if (cpi->sf.adaptive_motion_search)

         load_pred_mv(x, get_block_context(x, bsize));

       pick_sb_modes(cpi, tile, mi_row + ms, mi_col, &this_rate,

                     &this_dist, subsize, get_block_context(x, subsize),

                     best_rd - sum_rd);

       if (this_rate == INT_MAX) {

         sum_rd = INT64_MAX;

       } else {

         sum_rate += this_rate;

         sum_dist += this_dist;

         sum_rd = RDCOST(x->rdmult, x->rddiv, sum_rate, sum_dist);

       }

     }

     if (sum_rd < best_rd) {

       pl = partition_plane_context(cpi->above_seg_context,

                                    cpi->left_seg_context,

                                    mi_row, mi_col, bsize);

       sum_rate += x->partition_cost[pl][PARTITION_HORZ];

       sum_rd = RDCOST(x->rdmult, x->rddiv, sum_rate, sum_dist);

       if (sum_rd < best_rd) {

         best_rd = sum_rd;

         best_rate = sum_rate;

         best_dist = sum_dist;

         *(get_sb_partitioning(x, bsize)) = subsize;

       }

     }

     restore_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

   }

   // PARTITION_VERT

   if (partition_vert_allowed && do_rect) {

     subsize = get_subsize(bsize, PARTITION_VERT);

     *get_sb_index(x, subsize) = 0;

     if (cpi->sf.adaptive_motion_search)

       load_pred_mv(x, get_block_context(x, bsize));

     pick_sb_modes(cpi, tile, mi_row, mi_col, &sum_rate, &sum_dist, subsize,

                   get_block_context(x, subsize), best_rd);

     sum_rd = RDCOST(x->rdmult, x->rddiv, sum_rate, sum_dist);

     if (sum_rd < best_rd && mi_col + ms < cm->mi_cols) {

       update_state(cpi, get_block_context(x, subsize), subsize, 0);

       encode_superblock(cpi, tp, 0, mi_row, mi_col, subsize);

       *get_sb_index(x, subsize) = 1;

       if (cpi->sf.adaptive_motion_search)

         load_pred_mv(x, get_block_context(x, bsize));

       pick_sb_modes(cpi, tile, mi_row, mi_col + ms, &this_rate,

                     &this_dist, subsize, get_block_context(x, subsize),

                     best_rd - sum_rd);

       if (this_rate == INT_MAX) {

         sum_rd = INT64_MAX;

       } else {

         sum_rate += this_rate;

         sum_dist += this_dist;

         sum_rd = RDCOST(x->rdmult, x->rddiv, sum_rate, sum_dist);

       }

     }

     if (sum_rd < best_rd) {

       pl = partition_plane_context(cpi->above_seg_context,

                                    cpi->left_seg_context,

                                    mi_row, mi_col, bsize);

       sum_rate += x->partition_cost[pl][PARTITION_VERT];

       sum_rd = RDCOST(x->rdmult, x->rddiv, sum_rate, sum_dist);

       if (sum_rd < best_rd) {

         best_rate = sum_rate;

         best_dist = sum_dist;

         best_rd = sum_rd;

         *(get_sb_partitioning(x, bsize)) = subsize;

       }

     }

     restore_context(cpi, mi_row, mi_col, a, l, sa, sl, bsize);

   }

   *rate = best_rate;

   *dist = best_dist;

   if (best_rate < INT_MAX && best_dist < INT64_MAX && do_recon)

     encode_sb(cpi, tile, tp, mi_row, mi_col, bsize == BLOCK_64X64, bsize);

   if (bsize == BLOCK_64X64) {

     assert(tp_orig < *tp);

     assert(best_rate < INT_MAX);

     assert(best_dist < INT_MAX);

   } else {

     assert(tp_orig == *tp);

   }

 }

 // Examines 64x64 block and chooses a best reference frame

 static void rd_pick_reference_frame(VP9_COMP *cpi, const TileInfo *const tile,

                                     int mi_row, int mi_col) {

   VP9_COMMON * const cm = &cpi->common;

   MACROBLOCK * const x = &cpi->mb;

   int bsl = b_width_log2(BLOCK_64X64), bs = 1 << bsl;

   int ms = bs / 2;

   ENTROPY_CONTEXT l[16 * MAX_MB_PLANE], a[16 * MAX_MB_PLANE];

   PARTITION_CONTEXT sl[8], sa[8];

   int pl;

   int r;

   int64_t d;

   save_context(cpi, mi_row, mi_col, a, l, sa, sl, BLOCK_64X64);

   // Default is non mask (all reference frames allowed.

   cpi->ref_frame_mask = 0;

   // Do RD search for 64x64.

   if ((mi_row + (ms >> 1) < cm->mi_rows) &&

       (mi_col + (ms >> 1) < cm->mi_cols)) {

     cpi->set_ref_frame_mask = 1;

     pick_sb_modes(cpi, tile, mi_row, mi_col, &r, &d, BLOCK_64X64,

                   get_block_context(x, BLOCK_64X64), INT64_MAX);

     pl = partition_plane_context(cpi->above_seg_context, cpi->left_seg_context,

                                  mi_row, mi_col, BLOCK_64X64);

     r += x->partition_cost[pl][PARTITION_NONE];

     *(get_sb_partitioning(x, BLOCK_64X64)) = BLOCK_64X64;

     cpi->set_ref_frame_mask = 0;

   }

   restore_context(cpi, mi_row, mi_col, a, l, sa, sl, BLOCK_64X64);

 }

 static void encode_sb_row(VP9_COMP *cpi, const TileInfo *const tile,

                           int mi_row, TOKENEXTRA **tp) {

   VP9_COMMON * const cm = &cpi->common;

   int mi_col;

   // Initialize the left context for the new SB row

   vpx_memset(&cpi->left_context, 0, sizeof(cpi->left_context));

   vpx_memset(cpi->left_seg_context, 0, sizeof(cpi->left_seg_context));

   // Code each SB in the row

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

        mi_col += MI_BLOCK_SIZE) {

     int dummy_rate;

     int64_t dummy_dist;

     vp9_zero(cpi->mb.pred_mv);

     if (cpi->sf.reference_masking)

       rd_pick_reference_frame(cpi, tile, mi_row, mi_col);

     if (cpi->sf.use_lastframe_partitioning ||

         cpi->sf.use_one_partition_size_always ) {

       const int idx_str = cm->mode_info_stride * mi_row + mi_col;

       MODE_INFO **mi_8x8 = cm->mi_grid_visible + idx_str;

       MODE_INFO **prev_mi_8x8 = cm->prev_mi_grid_visible + idx_str;

       cpi->mb.source_variance = UINT_MAX;

       if (cpi->sf.use_one_partition_size_always) {

         set_offsets(cpi, tile, mi_row, mi_col, BLOCK_64X64);

         set_partitioning(cpi, tile, mi_8x8, mi_row, mi_col);

         rd_use_partition(cpi, tile, mi_8x8, tp, mi_row, mi_col, BLOCK_64X64,

                          &dummy_rate, &dummy_dist, 1);

       } else {

         if ((cpi->common.current_video_frame

             % cpi->sf.last_partitioning_redo_frequency) == 0

             || cm->prev_mi == 0

             || cpi->common.show_frame == 0

             || cpi->common.frame_type == KEY_FRAME

             || cpi->is_src_frame_alt_ref

             || ((cpi->sf.use_lastframe_partitioning ==

                  LAST_FRAME_PARTITION_LOW_MOTION) &&

                  sb_has_motion(cpi, prev_mi_8x8))) {

           // If required set upper and lower partition size limits

           if (cpi->sf.auto_min_max_partition_size) {

             set_offsets(cpi, tile, mi_row, mi_col, BLOCK_64X64);

             rd_auto_partition_range(cpi, tile, mi_row, mi_col,

                                     &cpi->sf.min_partition_size,

                                     &cpi->sf.max_partition_size);

           }

           rd_pick_partition(cpi, tile, tp, mi_row, mi_col, BLOCK_64X64,

                             &dummy_rate, &dummy_dist, 1, INT64_MAX);

         } else {

           copy_partitioning(cpi, mi_8x8, prev_mi_8x8);

           rd_use_partition(cpi, tile, mi_8x8, tp, mi_row, mi_col, BLOCK_64X64,

                            &dummy_rate, &dummy_dist, 1);

         }

       }

     } else {

       // If required set upper and lower partition size limits

       if (cpi->sf.auto_min_max_partition_size) {

         set_offsets(cpi, tile, mi_row, mi_col, BLOCK_64X64);

         rd_auto_partition_range(cpi, tile, mi_row, mi_col,

                                 &cpi->sf.min_partition_size,

                                 &cpi->sf.max_partition_size);

       }

       rd_pick_partition(cpi, tile, tp, mi_row, mi_col, BLOCK_64X64,

                         &dummy_rate, &dummy_dist, 1, INT64_MAX);

     }

   }

 }

 static void init_encode_frame_mb_context(VP9_COMP *cpi) {

   MACROBLOCK *const x = &cpi->mb;

   VP9_COMMON *const cm = &cpi->common;

   MACROBLOCKD *const xd = &x->e_mbd;

   const int aligned_mi_cols = mi_cols_aligned_to_sb(cm->mi_cols);

   x->act_zbin_adj = 0;

   cpi->seg0_idx = 0;

   xd->mode_info_stride = cm->mode_info_stride;

   // reset intra mode contexts

   if (frame_is_intra_only(cm))

     vp9_init_mbmode_probs(cm);

   // Copy data over into macro block data structures.

   vp9_setup_src_planes(x, cpi->Source, 0, 0);

   // TODO(jkoleszar): are these initializations required?

   setup_pre_planes(xd, 0, &cm->yv12_fb[cm->ref_frame_map[cpi->lst_fb_idx]],

                    0, 0, NULL);

   setup_dst_planes(xd, get_frame_new_buffer(cm), 0, 0);

   setup_block_dptrs(&x->e_mbd, cm->subsampling_x, cm->subsampling_y);

   xd->mi_8x8[0]->mbmi.mode = DC_PRED;

   xd->mi_8x8[0]->mbmi.uv_mode = DC_PRED;

   vp9_zero(cpi->y_mode_count);

   vp9_zero(cpi->y_uv_mode_count);

   vp9_zero(cm->counts.inter_mode);

   vp9_zero(cpi->partition_count);

   vp9_zero(cpi->intra_inter_count);

   vp9_zero(cpi->comp_inter_count);

   vp9_zero(cpi->single_ref_count);

   vp9_zero(cpi->comp_ref_count);

   vp9_zero(cm->counts.tx);

   vp9_zero(cm->counts.mbskip);

   // Note: this memset assumes above_context[0], [1] and [2]

   // are allocated as part of the same buffer.

   vpx_memset(cpi->above_context[0], 0,

              sizeof(*cpi->above_context[0]) *

              2 * aligned_mi_cols * MAX_MB_PLANE);

   vpx_memset(cpi->above_seg_context, 0,

              sizeof(*cpi->above_seg_context) * aligned_mi_cols);

 }

 static void switch_lossless_mode(VP9_COMP *cpi, int lossless) {

   if (lossless) {

     // printf("Switching to lossless\n");

     cpi->mb.fwd_txm4x4 = vp9_fwht4x4;

     cpi->mb.e_mbd.itxm_add = vp9_iwht4x4_add;

     cpi->mb.optimize = 0;

     cpi->common.lf.filter_level = 0;

     cpi->zbin_mode_boost_enabled = 0;

     cpi->common.tx_mode = ONLY_4X4;

   } else {

     // printf("Not lossless\n");

     cpi->mb.fwd_txm4x4 = vp9_fdct4x4;

     cpi->mb.e_mbd.itxm_add = vp9_idct4x4_add;

   }

 }

 static void switch_tx_mode(VP9_COMP *cpi) {

   if (cpi->sf.tx_size_search_method == USE_LARGESTALL &&

       cpi->common.tx_mode >= ALLOW_32X32)

     cpi->common.tx_mode = ALLOW_32X32;

 }

 static void encode_frame_internal(VP9_COMP *cpi) {

   int mi_row;

   MACROBLOCK * const x = &cpi->mb;

   VP9_COMMON * const cm = &cpi->common;

   MACROBLOCKD * const xd = &x->e_mbd;

 //  fprintf(stderr, "encode_frame_internal frame %d (%d) type %d\n",

 //           cpi->common.current_video_frame, cpi->common.show_frame,

 //           cm->frame_type);

 // debug output

 #if DBG_PRNT_SEGMAP

   {

     FILE *statsfile;

     statsfile = fopen("segmap2.stt", "a");

     fprintf(statsfile, "\n");

     fclose(statsfile);

   }

 #endif

   vp9_zero(cm->counts.switchable_interp);

   vp9_zero(cpi->tx_stepdown_count);

   xd->mi_8x8 = cm->mi_grid_visible;

   // required for vp9_frame_init_quantizer

   xd->mi_8x8[0] = cm->mi;

   xd->last_mi = cm->prev_mi;

   vp9_zero(cpi->NMVcount);

   vp9_zero(cpi->coef_counts);

   vp9_zero(cm->counts.eob_branch);

   cpi->mb.e_mbd.lossless = cm->base_qindex == 0 && cm->y_dc_delta_q == 0

       && cm->uv_dc_delta_q == 0 && cm->uv_ac_delta_q == 0;

   switch_lossless_mode(cpi, cpi->mb.e_mbd.lossless);

   vp9_frame_init_quantizer(cpi);

   vp9_initialize_rd_consts(cpi);

   vp9_initialize_me_consts(cpi, cm->base_qindex);

   switch_tx_mode(cpi);

   if (cpi->oxcf.tuning == VP8_TUNE_SSIM) {

     // Initialize encode frame context.

     init_encode_frame_mb_context(cpi);

     // Build a frame level activity map

     build_activity_map(cpi);

   }

   // Re-initialize encode frame context.

   init_encode_frame_mb_context(cpi);

   vp9_zero(cpi->rd_comp_pred_diff);

   vp9_zero(cpi->rd_filter_diff);

   vp9_zero(cpi->rd_tx_select_diff);

   vp9_zero(cpi->rd_tx_select_threshes);

   set_prev_mi(cm);

   {

     struct vpx_usec_timer emr_timer;

     vpx_usec_timer_start(&emr_timer);

     {

       // Take tiles into account and give start/end MB

       int tile_col, tile_row;

       TOKENEXTRA *tp = cpi->tok;

       const int tile_cols = 1 << cm->log2_tile_cols;

       const int tile_rows = 1 << cm->log2_tile_rows;

       for (tile_row = 0; tile_row < tile_rows; tile_row++) {

         for (tile_col = 0; tile_col < tile_cols; tile_col++) {

           TileInfo tile;

           TOKENEXTRA *tp_old = tp;

           // For each row of SBs in the frame

           vp9_tile_init(&tile, cm, tile_row, tile_col);

           for (mi_row = tile.mi_row_start;

                mi_row < tile.mi_row_end; mi_row += 8)

             encode_sb_row(cpi, &tile, mi_row, &tp);

           cpi->tok_count[tile_row][tile_col] = (unsigned int)(tp - tp_old);

           assert(tp - cpi->tok <= get_token_alloc(cm->mb_rows, cm->mb_cols));

         }

       }

     }

     vpx_usec_timer_mark(&emr_timer);

     cpi->time_encode_sb_row += vpx_usec_timer_elapsed(&emr_timer);

   }

   if (cpi->sf.skip_encode_sb) {

     int j;

     unsigned int intra_count = 0, inter_count = 0;

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

       intra_count += cpi->intra_inter_count[j][0];

       inter_count += cpi->intra_inter_count[j][1];

     }

     cpi->sf.skip_encode_frame = ((intra_count << 2) < inter_count);

     cpi->sf.skip_encode_frame &= (cm->frame_type != KEY_FRAME);

     cpi->sf.skip_encode_frame &= cm->show_frame;

   } else {

     cpi->sf.skip_encode_frame = 0;

   }

 #if 0

   // Keep record of the total distortion this time around for future use

   cpi->last_frame_distortion = cpi->frame_distortion;

 #endif

 }

 static int check_dual_ref_flags(VP9_COMP *cpi) {

   const int ref_flags = cpi->ref_frame_flags;

   if (vp9_segfeature_active(&cpi->common.seg, 1, SEG_LVL_REF_FRAME)) {

     return 0;

   } else {

     return (!!(ref_flags & VP9_GOLD_FLAG) + !!(ref_flags & VP9_LAST_FLAG)

         + !!(ref_flags & VP9_ALT_FLAG)) >= 2;

   }

 }

 static int get_skip_flag(MODE_INFO **mi_8x8, int mis, int ymbs, int xmbs) {

   int x, y;

   for (y = 0; y < ymbs; y++) {

     for (x = 0; x < xmbs; x++) {

       if (!mi_8x8[y * mis + x]->mbmi.skip_coeff)

         return 0;

     }

   }

   return 1;

 }

 static void set_txfm_flag(MODE_INFO **mi_8x8, int mis, int ymbs, int xmbs,

                           TX_SIZE tx_size) {

   int x, y;

   for (y = 0; y < ymbs; y++) {

     for (x = 0; x < xmbs; x++)

       mi_8x8[y * mis + x]->mbmi.tx_size = tx_size;

   }

 }

 static void reset_skip_txfm_size_b(VP9_COMP *cpi, MODE_INFO **mi_8x8,

                                    int mis, TX_SIZE max_tx_size, int bw, int bh,

                                    int mi_row, int mi_col, BLOCK_SIZE bsize) {

   VP9_COMMON * const cm = &cpi->common;

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

     return;

   } else {

     MB_MODE_INFO * const mbmi = &mi_8x8[0]->mbmi;

     if (mbmi->tx_size > max_tx_size) {

       const int ymbs = MIN(bh, cm->mi_rows - mi_row);

       const int xmbs = MIN(bw, cm->mi_cols - mi_col);

       assert(vp9_segfeature_active(&cm->seg, mbmi->segment_id, SEG_LVL_SKIP) ||

              get_skip_flag(mi_8x8, mis, ymbs, xmbs));

       set_txfm_flag(mi_8x8, mis, ymbs, xmbs, max_tx_size);

     }

   }

 }

 static void reset_skip_txfm_size_sb(VP9_COMP *cpi, MODE_INFO **mi_8x8,

                                     TX_SIZE max_tx_size, int mi_row, int mi_col,

                                     BLOCK_SIZE bsize) {

   VP9_COMMON * const cm = &cpi->common;

   const int mis = cm->mode_info_stride;

   int bw, bh;

   const int bs = num_8x8_blocks_wide_lookup[bsize], hbs = bs / 2;

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

     return;

   bw = num_8x8_blocks_wide_lookup[mi_8x8[0]->mbmi.sb_type];

   bh = num_8x8_blocks_high_lookup[mi_8x8[0]->mbmi.sb_type];

   if (bw == bs && bh == bs) {

     reset_skip_txfm_size_b(cpi, mi_8x8, mis, max_tx_size, bs, bs, mi_row,

                            mi_col, bsize);

   } else if (bw == bs && bh < bs) {

     reset_skip_txfm_size_b(cpi, mi_8x8, mis, max_tx_size, bs, hbs, mi_row,

                            mi_col, bsize);

     reset_skip_txfm_size_b(cpi, mi_8x8 + hbs * mis, mis, max_tx_size, bs, hbs,

                            mi_row + hbs, mi_col, bsize);

   } else if (bw < bs && bh == bs) {

     reset_skip_txfm_size_b(cpi, mi_8x8, mis, max_tx_size, hbs, bs, mi_row,

                            mi_col, bsize);

     reset_skip_txfm_size_b(cpi, mi_8x8 + hbs, mis, max_tx_size, hbs, bs, mi_row,

                            mi_col + hbs, bsize);

   } else {

     const BLOCK_SIZE subsize = subsize_lookup[PARTITION_SPLIT][bsize];

     int n;

     assert(bw < bs && bh < bs);

     for (n = 0; n < 4; n++) {

       const int mi_dc = hbs * (n & 1);

       const int mi_dr = hbs * (n >> 1);

       reset_skip_txfm_size_sb(cpi, &mi_8x8[mi_dr * mis + mi_dc], max_tx_size,

                               mi_row + mi_dr, mi_col + mi_dc, subsize);

     }

   }

 }

 static void reset_skip_txfm_size(VP9_COMP *cpi, TX_SIZE txfm_max) {

   VP9_COMMON * const cm = &cpi->common;

   int mi_row, mi_col;

   const int mis = cm->mode_info_stride;

 //  MODE_INFO *mi, *mi_ptr = cm->mi;

   MODE_INFO **mi_8x8, **mi_ptr = cm->mi_grid_visible;

   for (mi_row = 0; mi_row < cm->mi_rows; mi_row += 8, mi_ptr += 8 * mis) {

     mi_8x8 = mi_ptr;

     for (mi_col = 0; mi_col < cm->mi_cols; mi_col += 8, mi_8x8 += 8) {

       reset_skip_txfm_size_sb(cpi, mi_8x8, txfm_max, mi_row, mi_col,

                               BLOCK_64X64);

     }

   }

 }

 static int get_frame_type(VP9_COMP *cpi) {

   int frame_type;

   if (frame_is_intra_only(&cpi->common))

     frame_type = 0;

   else if (cpi->is_src_frame_alt_ref && cpi->refresh_golden_frame)

     frame_type = 3;

   else if (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)

     frame_type = 1;

   else

     frame_type = 2;

   return frame_type;

 }

 static void select_tx_mode(VP9_COMP *cpi) {

   if (cpi->oxcf.lossless) {

     cpi->common.tx_mode = ONLY_4X4;

   } else if (cpi->common.current_video_frame == 0) {

     cpi->common.tx_mode = TX_MODE_SELECT;

   } else {

     if (cpi->sf.tx_size_search_method == USE_LARGESTALL) {

       cpi->common.tx_mode = ALLOW_32X32;

     } else if (cpi->sf.tx_size_search_method == USE_FULL_RD) {

       int frame_type = get_frame_type(cpi);

       cpi->common.tx_mode =

           cpi->rd_tx_select_threshes[frame_type][ALLOW_32X32]

           > cpi->rd_tx_select_threshes[frame_type][TX_MODE_SELECT] ?

           ALLOW_32X32 : TX_MODE_SELECT;

     } else {

       unsigned int total = 0;

       int i;

       for (i = 0; i < TX_SIZES; ++i)

         total += cpi->tx_stepdown_count[i];

       if (total) {

         double fraction = (double)cpi->tx_stepdown_count[0] / total;

         cpi->common.tx_mode = fraction > 0.90 ? ALLOW_32X32 : TX_MODE_SELECT;

         // printf("fraction = %f\n", fraction);

       }  // else keep unchanged

     }

   }

 }

 void vp9_encode_frame(VP9_COMP *cpi) {

   VP9_COMMON * const cm = &cpi->common;

   // In the longer term the encoder should be generalized to match the

   // decoder such that we allow compound where one of the 3 buffers has a

   // different sign bias and that buffer is then the fixed ref. However, this

   // requires further work in the rd loop. For now the only supported encoder

   // side behavior is where the ALT ref buffer has opposite sign bias to

   // the other two.

   if (!frame_is_intra_only(cm)) {

     if ((cm->ref_frame_sign_bias[ALTREF_FRAME]

          == cm->ref_frame_sign_bias[GOLDEN_FRAME])

         || (cm->ref_frame_sign_bias[ALTREF_FRAME]

             == cm->ref_frame_sign_bias[LAST_FRAME])) {

       cm->allow_comp_inter_inter = 0;

     } else {

       cm->allow_comp_inter_inter = 1;

       cm->comp_fixed_ref = ALTREF_FRAME;

       cm->comp_var_ref[0] = LAST_FRAME;

       cm->comp_var_ref[1] = GOLDEN_FRAME;

     }

   }

   if (cpi->sf.RD) {

     int i, pred_type;

     INTERPOLATION_TYPE filter_type;

     /*

      * This code does a single RD pass over the whole frame assuming

      * either compound, single or hybrid prediction as per whatever has

      * worked best for that type of frame in the past.

      * It also predicts whether another coding mode would have worked

      * better that this coding mode. If that is the case, it remembers

      * that for subsequent frames.

      * It does the same analysis for transform size selection also.

      */

     int frame_type = get_frame_type(cpi);

     /* prediction (compound, single or hybrid) mode selection */

     if (frame_type == 3 || !cm->allow_comp_inter_inter)

       pred_type = SINGLE_PREDICTION_ONLY;

     else if (cpi->rd_prediction_type_threshes[frame_type][1]

              > cpi->rd_prediction_type_threshes[frame_type][0]

              && cpi->rd_prediction_type_threshes[frame_type][1]

              > cpi->rd_prediction_type_threshes[frame_type][2]

              && check_dual_ref_flags(cpi) && cpi->static_mb_pct == 100)

       pred_type = COMP_PREDICTION_ONLY;

     else if (cpi->rd_prediction_type_threshes[frame_type][0]

              > cpi->rd_prediction_type_threshes[frame_type][2])

       pred_type = SINGLE_PREDICTION_ONLY;

     else

       pred_type = HYBRID_PREDICTION;

     /* filter type selection */

     // FIXME(rbultje) for some odd reason, we often select smooth_filter

     // as default filter for ARF overlay frames. This is a REALLY BAD

     // IDEA so we explicitly disable it here.

     if (frame_type != 3 &&

         cpi->rd_filter_threshes[frame_type][1] >

             cpi->rd_filter_threshes[frame_type][0] &&

         cpi->rd_filter_threshes[frame_type][1] >

             cpi->rd_filter_threshes[frame_type][2] &&

         cpi->rd_filter_threshes[frame_type][1] >

             cpi->rd_filter_threshes[frame_type][SWITCHABLE_FILTERS]) {

       filter_type = EIGHTTAP_SMOOTH;

     } else if (cpi->rd_filter_threshes[frame_type][2] >

             cpi->rd_filter_threshes[frame_type][0] &&

         cpi->rd_filter_threshes[frame_type][2] >

             cpi->rd_filter_threshes[frame_type][SWITCHABLE_FILTERS]) {

       filter_type = EIGHTTAP_SHARP;

     } else if (cpi->rd_filter_threshes[frame_type][0] >

                   cpi->rd_filter_threshes[frame_type][SWITCHABLE_FILTERS]) {

       filter_type = EIGHTTAP;

     } else {

       filter_type = SWITCHABLE;

     }

     cpi->mb.e_mbd.lossless = 0;

     if (cpi->oxcf.lossless) {

       cpi->mb.e_mbd.lossless = 1;

     }

     /* transform size selection (4x4, 8x8, 16x16 or select-per-mb) */

     select_tx_mode(cpi);

     cpi->common.comp_pred_mode = pred_type;

     cpi->common.mcomp_filter_type = filter_type;

     encode_frame_internal(cpi);

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

       const int diff = (int) (cpi->rd_comp_pred_diff[i] / cpi->common.MBs);

       cpi->rd_prediction_type_threshes[frame_type][i] += diff;

       cpi->rd_prediction_type_threshes[frame_type][i] >>= 1;

     }

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

       const int64_t diff = cpi->rd_filter_diff[i] / cpi->common.MBs;

       cpi->rd_filter_threshes[frame_type][i] =

           (cpi->rd_filter_threshes[frame_type][i] + diff) / 2;

     }

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

       int64_t pd = cpi->rd_tx_select_diff[i];

       int diff;

       if (i == TX_MODE_SELECT)

         pd -= RDCOST(cpi->mb.rdmult, cpi->mb.rddiv,

                      2048 * (TX_SIZES - 1), 0);

       diff = (int) (pd / cpi->common.MBs);

       cpi->rd_tx_select_threshes[frame_type][i] += diff;

       cpi->rd_tx_select_threshes[frame_type][i] /= 2;

     }

     if (cpi->common.comp_pred_mode == HYBRID_PREDICTION) {

       int single_count_zero = 0;

       int comp_count_zero = 0;

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

         single_count_zero += cpi->comp_inter_count[i][0];

         comp_count_zero += cpi->comp_inter_count[i][1];

       }

       if (comp_count_zero == 0) {

         cpi->common.comp_pred_mode = SINGLE_PREDICTION_ONLY;

         vp9_zero(cpi->comp_inter_count);

       } else if (single_count_zero == 0) {

         cpi->common.comp_pred_mode = COMP_PREDICTION_ONLY;

         vp9_zero(cpi->comp_inter_count);

       }

     }

     if (cpi->common.tx_mode == TX_MODE_SELECT) {

       int count4x4 = 0;

       int count8x8_lp = 0, count8x8_8x8p = 0;

       int count16x16_16x16p = 0, count16x16_lp = 0;

       int count32x32 = 0;

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

         count4x4 += cm->counts.tx.p32x32[i][TX_4X4];

         count4x4 += cm->counts.tx.p16x16[i][TX_4X4];

         count4x4 += cm->counts.tx.p8x8[i][TX_4X4];

         count8x8_lp += cm->counts.tx.p32x32[i][TX_8X8];

         count8x8_lp += cm->counts.tx.p16x16[i][TX_8X8];

         count8x8_8x8p += cm->counts.tx.p8x8[i][TX_8X8];

         count16x16_16x16p += cm->counts.tx.p16x16[i][TX_16X16];

         count16x16_lp += cm->counts.tx.p32x32[i][TX_16X16];

         count32x32 += cm->counts.tx.p32x32[i][TX_32X32];

       }

       if (count4x4 == 0 && count16x16_lp == 0 && count16x16_16x16p == 0

           && count32x32 == 0) {

         cpi->common.tx_mode = ALLOW_8X8;

         reset_skip_txfm_size(cpi, TX_8X8);

       } else if (count8x8_8x8p == 0 && count16x16_16x16p == 0

                  && count8x8_lp == 0 && count16x16_lp == 0 && count32x32 == 0) {

         cpi->common.tx_mode = ONLY_4X4;

         reset_skip_txfm_size(cpi, TX_4X4);

       } else if (count8x8_lp == 0 && count16x16_lp == 0 && count4x4 == 0) {

         cpi->common.tx_mode = ALLOW_32X32;

       } else if (count32x32 == 0 && count8x8_lp == 0 && count4x4 == 0) {

         cpi->common.tx_mode = ALLOW_16X16;

         reset_skip_txfm_size(cpi, TX_16X16);

       }

     }

   } else {

     encode_frame_internal(cpi);

   }

 }

 static void sum_intra_stats(VP9_COMP *cpi, const MODE_INFO *mi) {

   const MB_PREDICTION_MODE y_mode = mi->mbmi.mode;

   const MB_PREDICTION_MODE uv_mode = mi->mbmi.uv_mode;

   const BLOCK_SIZE bsize = mi->mbmi.sb_type;

   ++cpi->y_uv_mode_count[y_mode][uv_mode];

   if (bsize < BLOCK_8X8) {

     int idx, idy;

     const int num_4x4_blocks_wide = num_4x4_blocks_wide_lookup[bsize];

     const int num_4x4_blocks_high = num_4x4_blocks_high_lookup[bsize];

     for (idy = 0; idy < 2; idy += num_4x4_blocks_high)

       for (idx = 0; idx < 2; idx += num_4x4_blocks_wide)

         ++cpi->y_mode_count[0][mi->bmi[idy * 2 + idx].as_mode];

   } else {

     ++cpi->y_mode_count[size_group_lookup[bsize]][y_mode];

   }

 }

 // Experimental stub function to create a per MB zbin adjustment based on

 // some previously calculated measure of MB activity.

 static void adjust_act_zbin(VP9_COMP *cpi, MACROBLOCK *x) {

 #if USE_ACT_INDEX

   x->act_zbin_adj = *(x->mb_activity_ptr);

 #else

   int64_t a;

   int64_t b;

   int64_t act = *(x->mb_activity_ptr);

   // Apply the masking to the RD multiplier.

   a = act + 4 * cpi->activity_avg;

   b = 4 * act + cpi->activity_avg;

   if (act > cpi->activity_avg)

     x->act_zbin_adj = (int) (((int64_t) b + (a >> 1)) / a) - 1;

   else

     x->act_zbin_adj = 1 - (int) (((int64_t) a + (b >> 1)) / b);

 #endif

 }

 static void encode_superblock(VP9_COMP *cpi, TOKENEXTRA **t, int output_enabled,

                               int mi_row, int mi_col, BLOCK_SIZE bsize) {

   VP9_COMMON * const cm = &cpi->common;

   MACROBLOCK * const x = &cpi->mb;

   MACROBLOCKD * const xd = &x->e_mbd;

   MODE_INFO **mi_8x8 = xd->mi_8x8;

   MODE_INFO *mi = mi_8x8[0];

   MB_MODE_INFO *mbmi = &mi->mbmi;

   PICK_MODE_CONTEXT *ctx = get_block_context(x, bsize);

   unsigned int segment_id = mbmi->segment_id;

   const int mis = cm->mode_info_stride;

   const int mi_width = num_8x8_blocks_wide_lookup[bsize];

   const int mi_height = num_8x8_blocks_high_lookup[bsize];

   x->skip_recode = !x->select_txfm_size && mbmi->sb_type >= BLOCK_8X8;

   x->skip_optimize = ctx->is_coded;

   ctx->is_coded = 1;

   x->use_lp32x32fdct = cpi->sf.use_lp32x32fdct;

   x->skip_encode = (!output_enabled && cpi->sf.skip_encode_frame &&

                     x->q_index < QIDX_SKIP_THRESH);

   if (x->skip_encode)

     return;

   if (cm->frame_type == KEY_FRAME) {

     if (cpi->oxcf.tuning == VP8_TUNE_SSIM) {

       adjust_act_zbin(cpi, x);

       vp9_update_zbin_extra(cpi, x);

     }

   } else {

     vp9_setup_interp_filters(xd, mbmi->interp_filter, cm);

     if (cpi->oxcf.tuning == VP8_TUNE_SSIM) {

       // Adjust the zbin based on this MB rate.

       adjust_act_zbin(cpi, x);

     }

     // Experimental code. Special case for gf and arf zeromv modes.

     // Increase zbin size to suppress noise

     cpi->zbin_mode_boost = 0;

     if (cpi->zbin_mode_boost_enabled) {

       if (is_inter_block(mbmi)) {

         if (mbmi->mode == ZEROMV) {

           if (mbmi->ref_frame[0] != LAST_FRAME)

             cpi->zbin_mode_boost = GF_ZEROMV_ZBIN_BOOST;

           else

             cpi->zbin_mode_boost = LF_ZEROMV_ZBIN_BOOST;

         } else if (mbmi->sb_type < BLOCK_8X8) {

           cpi->zbin_mode_boost = SPLIT_MV_ZBIN_BOOST;

         } else {

           cpi->zbin_mode_boost = MV_ZBIN_BOOST;

         }

       } else {

         cpi->zbin_mode_boost = INTRA_ZBIN_BOOST;

       }

     }

     vp9_update_zbin_extra(cpi, x);

   }

   if (!is_inter_block(mbmi)) {

     vp9_encode_intra_block_y(x, MAX(bsize, BLOCK_8X8));

     vp9_encode_intra_block_uv(x, MAX(bsize, BLOCK_8X8));

     if (output_enabled)

       sum_intra_stats(cpi, mi);

   } else {

     int idx = cm->ref_frame_map[get_ref_frame_idx(cpi, mbmi->ref_frame[0])];

     YV12_BUFFER_CONFIG *ref_fb = &cm->yv12_fb[idx];

     YV12_BUFFER_CONFIG *second_ref_fb = NULL;

     if (has_second_ref(mbmi)) {

       idx = cm->ref_frame_map[get_ref_frame_idx(cpi, mbmi->ref_frame[1])];

       second_ref_fb = &cm->yv12_fb[idx];

     }

     assert(cm->frame_type != KEY_FRAME);

     setup_pre_planes(xd, 0, ref_fb, mi_row, mi_col,

                      &xd->scale_factor[0]);

     setup_pre_planes(xd, 1, second_ref_fb, mi_row, mi_col,

                      &xd->scale_factor[1]);

     vp9_build_inter_predictors_sb(xd, mi_row, mi_col, MAX(bsize, BLOCK_8X8));

   }

   if (!is_inter_block(mbmi)) {

     vp9_tokenize_sb(cpi, t, !output_enabled, MAX(bsize, BLOCK_8X8));

   } else if (!x->skip) {

     vp9_encode_sb(x, MAX(bsize, BLOCK_8X8));

     vp9_tokenize_sb(cpi, t, !output_enabled, MAX(bsize, BLOCK_8X8));

   } else {

     int mb_skip_context = xd->left_available ? mi_8x8[-1]->mbmi.skip_coeff : 0;

     mb_skip_context += mi_8x8[-mis] ? mi_8x8[-mis]->mbmi.skip_coeff : 0;

     mbmi->skip_coeff = 1;

     if (output_enabled)

       cm->counts.mbskip[mb_skip_context][1]++;

     reset_skip_context(xd, MAX(bsize, BLOCK_8X8));

   }

   if (output_enabled) {

     if (cm->tx_mode == TX_MODE_SELECT &&

         mbmi->sb_type >= BLOCK_8X8  &&

         !(is_inter_block(mbmi) &&

             (mbmi->skip_coeff ||

              vp9_segfeature_active(&cm->seg, segment_id, SEG_LVL_SKIP)))) {

       const uint8_t context = vp9_get_pred_context_tx_size(xd);

       ++get_tx_counts(max_txsize_lookup[bsize],

                       context, &cm->counts.tx)[mbmi->tx_size];

     } else {

       int x, y;

       TX_SIZE sz = tx_mode_to_biggest_tx_size[cm->tx_mode];

       assert(sizeof(tx_mode_to_biggest_tx_size) /

              sizeof(tx_mode_to_biggest_tx_size[0]) == TX_MODES);

       // The new intra coding scheme requires no change of transform size

       if (is_inter_block(&mi->mbmi)) {

         if (sz == TX_32X32 && bsize < BLOCK_32X32)

           sz = TX_16X16;

         if (sz == TX_16X16 && bsize < BLOCK_16X16)

           sz = TX_8X8;

         if (sz == TX_8X8 && bsize < BLOCK_8X8)

           sz = TX_4X4;

       } else if (bsize >= BLOCK_8X8) {

         sz = mbmi->tx_size;

       } else {

         sz = TX_4X4;

       }

       for (y = 0; y < mi_height; y++)

         for (x = 0; x < mi_width; x++)

           if (mi_col + x < cm->mi_cols && mi_row + y < cm->mi_rows)

             mi_8x8[mis * y + x]->mbmi.tx_size = sz;

     }

   }

 }