The Tor Browser: media/libvpx/vp8/encoder/encodeframe.c@b8a032363ba2 (annotated)

media/libvpx/vp8/encoder/encodeframe.c@b8a032363ba2 (annotated)

media/libvpx/vp8/encoder/encodeframe.c

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /*
  *  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 "vpx_config.h"
 #include "vp8_rtcd.h"
 #include "encodemb.h"
 #include "encodemv.h"
 #include "vp8/common/common.h"
 #include "onyx_int.h"
 #include "vp8/common/extend.h"
 #include "vp8/common/entropymode.h"
 #include "vp8/common/quant_common.h"
 #include "segmentation.h"
 #include "vp8/common/setupintrarecon.h"
 #include "encodeintra.h"
 #include "vp8/common/reconinter.h"
 #include "rdopt.h"
 #include "pickinter.h"
 #include "vp8/common/findnearmv.h"
 #include <stdio.h>
 #include <limits.h>
 #include "vp8/common/invtrans.h"
 #include "vpx_ports/vpx_timer.h"
 #if CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING
 #include "bitstream.h"
 #endif
 #include "encodeframe.h"
 extern void vp8_stuff_mb(VP8_COMP *cpi, MACROBLOCK *x, TOKENEXTRA **t) ;
 extern void vp8_calc_ref_frame_costs(int *ref_frame_cost,
                                      int prob_intra,
                                      int prob_last,
                                      int prob_garf
                                     );
 extern void vp8_convert_rfct_to_prob(VP8_COMP *const cpi);
 extern void vp8cx_initialize_me_consts(VP8_COMP *cpi, int QIndex);
 extern void vp8_auto_select_speed(VP8_COMP *cpi);
 extern void vp8cx_init_mbrthread_data(VP8_COMP *cpi,
                                       MACROBLOCK *x,
                                       MB_ROW_COMP *mbr_ei,
                                       int count);
 static void adjust_act_zbin( VP8_COMP *cpi, MACROBLOCK *x );
 #ifdef MODE_STATS
 unsigned int inter_y_modes[10] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 unsigned int inter_uv_modes[4] = {0, 0, 0, 0};
 unsigned int inter_b_modes[15]  = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 unsigned int y_modes[5]   = {0, 0, 0, 0, 0};
 unsigned int uv_modes[4]  = {0, 0, 0, 0};
 unsigned int b_modes[14]  = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 #endif
 /* 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
  *  vp8_activity_masking().
  */
 #define VP8_ACTIVITY_AVG_MIN (64)
 /* 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 unsigned char VP8_VAR_OFFS[16]=
 {
 ,128,128,128,128,128,128,128,128,128,128,128,128,128,128,128
 };
 /* Original activity measure from Tim T's code. */
 static unsigned int tt_activity_measure( VP8_COMP *cpi, 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 =  vp8_variance16x16(x->src.y_buffer,
                     x->src.y_stride, VP8_VAR_OFFS, 0, &sse);
     act = 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( VP8_COMP *cpi,
                                           MACROBLOCK *x, int use_dc_pred )
 {
     return vp8_encode_intra(cpi,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( VP8_COMP *cpi, 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( cpi, x, use_dc_pred );
     }
     else
     {
         /* Original activity measure from Tim T's code. */
         mb_activity = tt_activity_measure( cpi, x );
     }
     if ( mb_activity < VP8_ACTIVITY_AVG_MIN )
         mb_activity = VP8_ACTIVITY_AVG_MIN;
     return mb_activity;
 }
 /* Calculate an "average" mb activity value for the frame */
 #define ACT_MEDIAN 0
 static void calc_av_activity( VP8_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(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
     if (cpi->activity_avg < VP8_ACTIVITY_AVG_MIN)
         cpi->activity_avg = VP8_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 and activity index for each mb */
 static void calc_activity_index( VP8_COMP *cpi, MACROBLOCK *x )
 {
     VP8_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
 /* Loop through all MBs. Note activity of each, average activity and
  * calculate a normalized activity for each
  */
 static void build_activity_map( VP8_COMP *cpi )
 {
     MACROBLOCK *const x = & cpi->mb;
     MACROBLOCKD *xd = &x->e_mbd;
     VP8_COMMON *const cm = & cpi->common;
 #if ALT_ACT_MEASURE
     YV12_BUFFER_CONFIG *new_yv12 = &cm->yv12_fb[cm->new_fb_idx];
     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;
     /* 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->dst.y_buffer = new_yv12->y_buffer + recon_yoffset;
             xd->left_available = (mb_col != 0);
             recon_yoffset += 16;
 #endif
             /* Copy current mb to a buffer */
             vp8_copy_mem16x16(x->src.y_buffer, x->src.y_stride, x->thismb, 16);
             /* measure activity */
             mb_activity = mb_activity_measure( cpi, 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->src.y_buffer += 16;
         }
         /* adjust to the next row of mbs */
         x->src.y_buffer += 16 * x->src.y_stride - 16 * cm->mb_cols;
 #if ALT_ACT_MEASURE
         /* extend the recon for intra prediction */
         vp8_extend_mb_row(new_yv12, xd->dst.y_buffer + 16,
                           xd->dst.u_buffer + 8, xd->dst.v_buffer + 8);
 #endif
     }
     /* 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 vp8_activity_masking(VP8_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 encode_mb_row(VP8_COMP *cpi,
                    VP8_COMMON *cm,
                    int mb_row,
                    MACROBLOCK  *x,
                    MACROBLOCKD *xd,
                    TOKENEXTRA **tp,
                    int *segment_counts,
                    int *totalrate)
 {
     int recon_yoffset, recon_uvoffset;
     int mb_col;
     int ref_fb_idx = cm->lst_fb_idx;
     int dst_fb_idx = cm->new_fb_idx;
     int recon_y_stride = cm->yv12_fb[ref_fb_idx].y_stride;
     int recon_uv_stride = cm->yv12_fb[ref_fb_idx].uv_stride;
     int map_index = (mb_row * cpi->common.mb_cols);
 #if (CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING)
     const int num_part = (1 << cm->multi_token_partition);
     TOKENEXTRA * tp_start = cpi->tok;
     vp8_writer *w;
 #endif
 #if CONFIG_MULTITHREAD
     const int nsync = cpi->mt_sync_range;
     const int rightmost_col = cm->mb_cols + nsync;
     volatile const int *last_row_current_mb_col;
     volatile int *current_mb_col = &cpi->mt_current_mb_col[mb_row];
     if ((cpi->b_multi_threaded != 0) && (mb_row != 0))
         last_row_current_mb_col = &cpi->mt_current_mb_col[mb_row - 1];
     else
         last_row_current_mb_col = &rightmost_col;
 #endif
 #if (CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING)
     if(num_part > 1)
         w= &cpi->bc[1 + (mb_row % num_part)];
     else
         w = &cpi->bc[1];
 #endif
     /* reset above block coeffs */
     xd->above_context = cm->above_context;
     xd->up_available = (mb_row != 0);
     recon_yoffset = (mb_row * recon_y_stride * 16);
     recon_uvoffset = (mb_row * recon_uv_stride * 8);
     cpi->tplist[mb_row].start = *tp;
     /* printf("Main mb_row = %d\n", mb_row); */
     /* Distance of Mb to the top & bottom edges, specified in 1/8th pel
      * units as they are always compared to values that are in 1/8th pel
      */
     xd->mb_to_top_edge = -((mb_row * 16) << 3);
     xd->mb_to_bottom_edge = ((cm->mb_rows - 1 - mb_row) * 16) << 3;
     /* Set up limit values for vertical motion vector components
      * to prevent them extending beyond the UMV borders
      */
     x->mv_row_min = -((mb_row * 16) + (VP8BORDERINPIXELS - 16));
     x->mv_row_max = ((cm->mb_rows - 1 - mb_row) * 16)
                         + (VP8BORDERINPIXELS - 16);
     /* Set the mb activity pointer to the start of the row. */
     x->mb_activity_ptr = &cpi->mb_activity_map[map_index];
     /* for each macroblock col in image */
     for (mb_col = 0; mb_col < cm->mb_cols; mb_col++)
     {
 #if  (CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING)
         *tp = cpi->tok;
 #endif
         /* Distance of Mb to the left & right edges, specified in
          * 1/8th pel units as they are always compared to values
          * that are in 1/8th pel units
          */
         xd->mb_to_left_edge = -((mb_col * 16) << 3);
         xd->mb_to_right_edge = ((cm->mb_cols - 1 - mb_col) * 16) << 3;
         /* Set up limit values for horizontal motion vector components
          * to prevent them extending beyond the UMV borders
          */
         x->mv_col_min = -((mb_col * 16) + (VP8BORDERINPIXELS - 16));
         x->mv_col_max = ((cm->mb_cols - 1 - mb_col) * 16)
                             + (VP8BORDERINPIXELS - 16);
         xd->dst.y_buffer = cm->yv12_fb[dst_fb_idx].y_buffer + recon_yoffset;
         xd->dst.u_buffer = cm->yv12_fb[dst_fb_idx].u_buffer + recon_uvoffset;
         xd->dst.v_buffer = cm->yv12_fb[dst_fb_idx].v_buffer + recon_uvoffset;
         xd->left_available = (mb_col != 0);
         x->rddiv = cpi->RDDIV;
         x->rdmult = cpi->RDMULT;
         /* Copy current mb to a buffer */
         vp8_copy_mem16x16(x->src.y_buffer, x->src.y_stride, x->thismb, 16);
 #if CONFIG_MULTITHREAD
         if (cpi->b_multi_threaded != 0)
         {
             *current_mb_col = mb_col - 1; /* set previous MB done */
             if ((mb_col & (nsync - 1)) == 0)
             {
                 while (mb_col > (*last_row_current_mb_col - nsync))
                 {
                     x86_pause_hint();
                     thread_sleep(0);
                 }
             }
         }
 #endif
         if(cpi->oxcf.tuning == VP8_TUNE_SSIM)
             vp8_activity_masking(cpi, x);
         /* Is segmentation enabled */
         /* MB level adjustment to quantizer */
         if (xd->segmentation_enabled)
         {
             /* Code to set segment id in xd->mbmi.segment_id for current MB
              * (with range checking)
              */
             if (cpi->segmentation_map[map_index+mb_col] <= 3)
                 xd->mode_info_context->mbmi.segment_id = cpi->segmentation_map[map_index+mb_col];
             else
                 xd->mode_info_context->mbmi.segment_id = 0;
             vp8cx_mb_init_quantizer(cpi, x, 1);
         }
         else
             /* Set to Segment 0 by default */
             xd->mode_info_context->mbmi.segment_id = 0;
         x->active_ptr = cpi->active_map + map_index + mb_col;
         if (cm->frame_type == KEY_FRAME)
         {
             *totalrate += vp8cx_encode_intra_macroblock(cpi, x, tp);
 #ifdef MODE_STATS
             y_modes[xd->mbmi.mode] ++;
 #endif
         }
         else
         {
             *totalrate += vp8cx_encode_inter_macroblock(cpi, x, tp, recon_yoffset, recon_uvoffset, mb_row, mb_col);
 #ifdef MODE_STATS
             inter_y_modes[xd->mbmi.mode] ++;
             if (xd->mbmi.mode == SPLITMV)
             {
                 int b;
                 for (b = 0; b < xd->mbmi.partition_count; b++)
                 {
                     inter_b_modes[x->partition->bmi[b].mode] ++;
                 }
             }
 #endif
             /* Special case code for cyclic refresh
              * If cyclic update enabled then copy xd->mbmi.segment_id; (which
              * may have been updated based on mode during
              * vp8cx_encode_inter_macroblock()) back into the global
              * segmentation map
              */
             if ((cpi->current_layer == 0) &&
                 (cpi->cyclic_refresh_mode_enabled &&
                  xd->segmentation_enabled))
             {
                 cpi->segmentation_map[map_index+mb_col] = xd->mode_info_context->mbmi.segment_id;
                 /* If the block has been refreshed mark it as clean (the
                  * magnitude of the -ve influences how long it will be before
                  * we consider another refresh):
                  * Else if it was coded (last frame 0,0) and has not already
                  * been refreshed then mark it as a candidate for cleanup
                  * next time (marked 0) else mark it as dirty (1).
                  */
                 if (xd->mode_info_context->mbmi.segment_id)
                     cpi->cyclic_refresh_map[map_index+mb_col] = -1;
                 else if ((xd->mode_info_context->mbmi.mode == ZEROMV) && (xd->mode_info_context->mbmi.ref_frame == LAST_FRAME))
                 {
                     if (cpi->cyclic_refresh_map[map_index+mb_col] == 1)
                         cpi->cyclic_refresh_map[map_index+mb_col] = 0;
                 }
                 else
                     cpi->cyclic_refresh_map[map_index+mb_col] = 1;
             }
         }
         cpi->tplist[mb_row].stop = *tp;
 #if CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING
         /* pack tokens for this MB */
         {
             int tok_count = *tp - tp_start;
             pack_tokens(w, tp_start, tok_count);
         }
 #endif
         /* Increment pointer into gf usage flags structure. */
         x->gf_active_ptr++;
         /* Increment the activity mask pointers. */
         x->mb_activity_ptr++;
         /* adjust to the next column of macroblocks */
         x->src.y_buffer += 16;
         x->src.u_buffer += 8;
         x->src.v_buffer += 8;
         recon_yoffset += 16;
         recon_uvoffset += 8;
         /* Keep track of segment usage */
         segment_counts[xd->mode_info_context->mbmi.segment_id] ++;
         /* skip to next mb */
         xd->mode_info_context++;
         x->partition_info++;
         xd->above_context++;
     }
     /* extend the recon for intra prediction */
     vp8_extend_mb_row( &cm->yv12_fb[dst_fb_idx],
                         xd->dst.y_buffer + 16,
                         xd->dst.u_buffer + 8,
                         xd->dst.v_buffer + 8);
 #if CONFIG_MULTITHREAD
     if (cpi->b_multi_threaded != 0)
         *current_mb_col = rightmost_col;
 #endif
     /* this is to account for the border */
     xd->mode_info_context++;
     x->partition_info++;
 }
 static void init_encode_frame_mb_context(VP8_COMP *cpi)
 {
     MACROBLOCK *const x = & cpi->mb;
     VP8_COMMON *const cm = & cpi->common;
     MACROBLOCKD *const xd = & x->e_mbd;
     /* GF active flags data structure */
     x->gf_active_ptr = (signed char *)cpi->gf_active_flags;
     /* Activity map pointer */
     x->mb_activity_ptr = cpi->mb_activity_map;
     x->act_zbin_adj = 0;
     x->partition_info = x->pi;
     xd->mode_info_context = cm->mi;
     xd->mode_info_stride = cm->mode_info_stride;
     xd->frame_type = cm->frame_type;
     /* reset intra mode contexts */
     if (cm->frame_type == KEY_FRAME)
         vp8_init_mbmode_probs(cm);
     /* Copy data over into macro block data structures. */
     x->src = * cpi->Source;
     xd->pre = cm->yv12_fb[cm->lst_fb_idx];
     xd->dst = cm->yv12_fb[cm->new_fb_idx];
     /* set up frame for intra coded blocks */
     vp8_setup_intra_recon(&cm->yv12_fb[cm->new_fb_idx]);
     vp8_build_block_offsets(x);
     xd->mode_info_context->mbmi.mode = DC_PRED;
     xd->mode_info_context->mbmi.uv_mode = DC_PRED;
     xd->left_context = &cm->left_context;
     x->mvc = cm->fc.mvc;
     vpx_memset(cm->above_context, 0,
                sizeof(ENTROPY_CONTEXT_PLANES) * cm->mb_cols);
     /* Special case treatment when GF and ARF are not sensible options
      * for reference
      */
     if (cpi->ref_frame_flags == VP8_LAST_FRAME)
         vp8_calc_ref_frame_costs(x->ref_frame_cost,
                                  cpi->prob_intra_coded,255,128);
     else if ((cpi->oxcf.number_of_layers > 1) &&
                (cpi->ref_frame_flags == VP8_GOLD_FRAME))
         vp8_calc_ref_frame_costs(x->ref_frame_cost,
                                  cpi->prob_intra_coded,1,255);
     else if ((cpi->oxcf.number_of_layers > 1) &&
                 (cpi->ref_frame_flags == VP8_ALTR_FRAME))
         vp8_calc_ref_frame_costs(x->ref_frame_cost,
                                  cpi->prob_intra_coded,1,1);
     else
         vp8_calc_ref_frame_costs(x->ref_frame_cost,
                                  cpi->prob_intra_coded,
                                  cpi->prob_last_coded,
                                  cpi->prob_gf_coded);
     xd->fullpixel_mask = 0xffffffff;
     if(cm->full_pixel)
         xd->fullpixel_mask = 0xfffffff8;
     vp8_zero(x->coef_counts);
     vp8_zero(x->ymode_count);
     vp8_zero(x->uv_mode_count)
     x->prediction_error = 0;
     x->intra_error = 0;
     vp8_zero(x->count_mb_ref_frame_usage);
 }
 static void sum_coef_counts(MACROBLOCK *x, MACROBLOCK *x_thread)
 {
     int i = 0;
     do
     {
         int j = 0;
         do
         {
             int k = 0;
             do
             {
                 /* at every context */
                 /* calc probs and branch cts for this frame only */
                 int t = 0;      /* token/prob index */
                 do
                 {
                     x->coef_counts [i][j][k][t] +=
                         x_thread->coef_counts [i][j][k][t];
                 }
                 while (++t < ENTROPY_NODES);
             }
             while (++k < PREV_COEF_CONTEXTS);
         }
         while (++j < COEF_BANDS);
     }
     while (++i < BLOCK_TYPES);
 }
 void vp8_encode_frame(VP8_COMP *cpi)
 {
     int mb_row;
     MACROBLOCK *const x = & cpi->mb;
     VP8_COMMON *const cm = & cpi->common;
     MACROBLOCKD *const xd = & x->e_mbd;
     TOKENEXTRA *tp = cpi->tok;
     int segment_counts[MAX_MB_SEGMENTS];
     int totalrate;
 #if CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING
     BOOL_CODER * bc = &cpi->bc[1]; /* bc[0] is for control partition */
     const int num_part = (1 << cm->multi_token_partition);
 #endif
     vpx_memset(segment_counts, 0, sizeof(segment_counts));
     totalrate = 0;
     if (cpi->compressor_speed == 2)
     {
         if (cpi->oxcf.cpu_used < 0)
             cpi->Speed = -(cpi->oxcf.cpu_used);
         else
             vp8_auto_select_speed(cpi);
     }
     /* Functions setup for all frame types so we can use MC in AltRef */
     if(!cm->use_bilinear_mc_filter)
     {
         xd->subpixel_predict        = vp8_sixtap_predict4x4;
         xd->subpixel_predict8x4     = vp8_sixtap_predict8x4;
         xd->subpixel_predict8x8     = vp8_sixtap_predict8x8;
         xd->subpixel_predict16x16   = vp8_sixtap_predict16x16;
     }
     else
     {
         xd->subpixel_predict        = vp8_bilinear_predict4x4;
         xd->subpixel_predict8x4     = vp8_bilinear_predict8x4;
         xd->subpixel_predict8x8     = vp8_bilinear_predict8x8;
         xd->subpixel_predict16x16   = vp8_bilinear_predict16x16;
     }
     cpi->mb.skip_true_count = 0;
     cpi->tok_count = 0;
 #if 0
     /* Experimental code */
     cpi->frame_distortion = 0;
     cpi->last_mb_distortion = 0;
 #endif
     xd->mode_info_context = cm->mi;
     vp8_zero(cpi->mb.MVcount);
     vp8cx_frame_init_quantizer(cpi);
     vp8_initialize_rd_consts(cpi, x,
                              vp8_dc_quant(cm->base_qindex, cm->y1dc_delta_q));
     vp8cx_initialize_me_consts(cpi, cm->base_qindex);
     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-init encode frame context. */
     init_encode_frame_mb_context(cpi);
 #if CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING
     {
         int i;
         for(i = 0; i < num_part; i++)
         {
             vp8_start_encode(&bc[i], cpi->partition_d[i + 1],
                     cpi->partition_d_end[i + 1]);
             bc[i].error = &cm->error;
         }
     }
 #endif
     {
         struct vpx_usec_timer  emr_timer;
         vpx_usec_timer_start(&emr_timer);
 #if CONFIG_MULTITHREAD
         if (cpi->b_multi_threaded)
         {
             int i;
             vp8cx_init_mbrthread_data(cpi, x, cpi->mb_row_ei,
                                       cpi->encoding_thread_count);
             for (i = 0; i < cm->mb_rows; i++)
                 cpi->mt_current_mb_col[i] = -1;
             for (i = 0; i < cpi->encoding_thread_count; i++)
             {
                 sem_post(&cpi->h_event_start_encoding[i]);
             }
             for (mb_row = 0; mb_row < cm->mb_rows; mb_row += (cpi->encoding_thread_count + 1))
             {
                 vp8_zero(cm->left_context)
 #if CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING
                 tp = cpi->tok;
 #else
                 tp = cpi->tok + mb_row * (cm->mb_cols * 16 * 24);
 #endif
                 encode_mb_row(cpi, cm, mb_row, x, xd, &tp, segment_counts, &totalrate);
                 /* adjust to the next row of mbs */
                 x->src.y_buffer += 16 * x->src.y_stride * (cpi->encoding_thread_count + 1) - 16 * cm->mb_cols;
                 x->src.u_buffer +=  8 * x->src.uv_stride * (cpi->encoding_thread_count + 1) - 8 * cm->mb_cols;
                 x->src.v_buffer +=  8 * x->src.uv_stride * (cpi->encoding_thread_count + 1) - 8 * cm->mb_cols;
                 xd->mode_info_context += xd->mode_info_stride * cpi->encoding_thread_count;
                 x->partition_info  += xd->mode_info_stride * cpi->encoding_thread_count;
                 x->gf_active_ptr   += cm->mb_cols * cpi->encoding_thread_count;
                 if(mb_row == cm->mb_rows - 1)
                 {
                     sem_post(&cpi->h_event_end_encoding); /* signal frame encoding end */
                 }
             }
             sem_wait(&cpi->h_event_end_encoding); /* wait for other threads to finish */
             for (mb_row = 0; mb_row < cm->mb_rows; mb_row ++)
             {
                 cpi->tok_count += (unsigned int)
                   (cpi->tplist[mb_row].stop - cpi->tplist[mb_row].start);
             }
             if (xd->segmentation_enabled)
             {
                 int j;
                 if (xd->segmentation_enabled)
                 {
                     for (i = 0; i < cpi->encoding_thread_count; i++)
                     {
                         for (j = 0; j < 4; j++)
                             segment_counts[j] += cpi->mb_row_ei[i].segment_counts[j];
                     }
                 }
             }
             for (i = 0; i < cpi->encoding_thread_count; i++)
             {
                 int mode_count;
                 int c_idx;
                 totalrate += cpi->mb_row_ei[i].totalrate;
                 cpi->mb.skip_true_count += cpi->mb_row_ei[i].mb.skip_true_count;
                 for(mode_count = 0; mode_count < VP8_YMODES; mode_count++)
                     cpi->mb.ymode_count[mode_count] +=
                         cpi->mb_row_ei[i].mb.ymode_count[mode_count];
                 for(mode_count = 0; mode_count < VP8_UV_MODES; mode_count++)
                     cpi->mb.uv_mode_count[mode_count] +=
                         cpi->mb_row_ei[i].mb.uv_mode_count[mode_count];
                 for(c_idx = 0; c_idx < MVvals; c_idx++)
                 {
                     cpi->mb.MVcount[0][c_idx] +=
                         cpi->mb_row_ei[i].mb.MVcount[0][c_idx];
                     cpi->mb.MVcount[1][c_idx] +=
                         cpi->mb_row_ei[i].mb.MVcount[1][c_idx];
                 }
                 cpi->mb.prediction_error +=
                     cpi->mb_row_ei[i].mb.prediction_error;
                 cpi->mb.intra_error += cpi->mb_row_ei[i].mb.intra_error;
                 for(c_idx = 0; c_idx < MAX_REF_FRAMES; c_idx++)
                     cpi->mb.count_mb_ref_frame_usage[c_idx] +=
                         cpi->mb_row_ei[i].mb.count_mb_ref_frame_usage[c_idx];
                 for(c_idx = 0; c_idx < MAX_ERROR_BINS; c_idx++)
                     cpi->mb.error_bins[c_idx] +=
                         cpi->mb_row_ei[i].mb.error_bins[c_idx];
                 /* add up counts for each thread */
                 sum_coef_counts(x, &cpi->mb_row_ei[i].mb);
             }
         }
         else
 #endif
         {
             /* for each macroblock row in image */
             for (mb_row = 0; mb_row < cm->mb_rows; mb_row++)
             {
                 vp8_zero(cm->left_context)
 #if CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING
                 tp = cpi->tok;
 #endif
                 encode_mb_row(cpi, cm, mb_row, x, xd, &tp, segment_counts, &totalrate);
                 /* adjust to the next row of mbs */
                 x->src.y_buffer += 16 * x->src.y_stride - 16 * cm->mb_cols;
                 x->src.u_buffer += 8 * x->src.uv_stride - 8 * cm->mb_cols;
                 x->src.v_buffer += 8 * x->src.uv_stride - 8 * cm->mb_cols;
             }
             cpi->tok_count = (unsigned int)(tp - cpi->tok);
         }
 #if CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING
         {
             int i;
             for(i = 0; i < num_part; i++)
             {
                 vp8_stop_encode(&bc[i]);
                 cpi->partition_sz[i+1] = bc[i].pos;
             }
         }
 #endif
         vpx_usec_timer_mark(&emr_timer);
         cpi->time_encode_mb_row += vpx_usec_timer_elapsed(&emr_timer);
     }
     // Work out the segment probabilities if segmentation is enabled
     // and needs to be updated
     if (xd->segmentation_enabled && xd->update_mb_segmentation_map)
     {
         int tot_count;
         int i;
         /* Set to defaults */
         vpx_memset(xd->mb_segment_tree_probs, 255 , sizeof(xd->mb_segment_tree_probs));
         tot_count = segment_counts[0] + segment_counts[1] + segment_counts[2] + segment_counts[3];
         if (tot_count)
         {
             xd->mb_segment_tree_probs[0] = ((segment_counts[0] + segment_counts[1]) * 255) / tot_count;
             tot_count = segment_counts[0] + segment_counts[1];
             if (tot_count > 0)
             {
                 xd->mb_segment_tree_probs[1] = (segment_counts[0] * 255) / tot_count;
             }
             tot_count = segment_counts[2] + segment_counts[3];
             if (tot_count > 0)
                 xd->mb_segment_tree_probs[2] = (segment_counts[2] * 255) / tot_count;
             /* Zero probabilities not allowed */
             for (i = 0; i < MB_FEATURE_TREE_PROBS; i ++)
             {
                 if (xd->mb_segment_tree_probs[i] == 0)
                     xd->mb_segment_tree_probs[i] = 1;
             }
         }
     }
     /* projected_frame_size in units of BYTES */
     cpi->projected_frame_size = totalrate >> 8;
     /* Make a note of the percentage MBs coded Intra. */
     if (cm->frame_type == KEY_FRAME)
     {
         cpi->this_frame_percent_intra = 100;
     }
     else
     {
         int tot_modes;
         tot_modes = cpi->mb.count_mb_ref_frame_usage[INTRA_FRAME]
                     + cpi->mb.count_mb_ref_frame_usage[LAST_FRAME]
                     + cpi->mb.count_mb_ref_frame_usage[GOLDEN_FRAME]
                     + cpi->mb.count_mb_ref_frame_usage[ALTREF_FRAME];
         if (tot_modes)
             cpi->this_frame_percent_intra =
                 cpi->mb.count_mb_ref_frame_usage[INTRA_FRAME] * 100 / tot_modes;
     }
 #if ! CONFIG_REALTIME_ONLY
     /* Adjust the projected reference frame usage probability numbers to
      * reflect what we have just seen. This may be useful when we make
      * multiple iterations of the recode loop rather than continuing to use
      * values from the previous frame.
      */
     if ((cm->frame_type != KEY_FRAME) && ((cpi->oxcf.number_of_layers > 1) ||
         (!cm->refresh_alt_ref_frame && !cm->refresh_golden_frame)))
     {
       vp8_convert_rfct_to_prob(cpi);
     }
 #endif
 }
 void vp8_setup_block_ptrs(MACROBLOCK *x)
 {
     int r, c;
     int i;
     for (r = 0; r < 4; r++)
     {
         for (c = 0; c < 4; c++)
         {
             x->block[r*4+c].src_diff = x->src_diff + r * 4 * 16 + c * 4;
         }
     }
     for (r = 0; r < 2; r++)
     {
         for (c = 0; c < 2; c++)
         {
             x->block[16 + r*2+c].src_diff = x->src_diff + 256 + r * 4 * 8 + c * 4;
         }
     }
     for (r = 0; r < 2; r++)
     {
         for (c = 0; c < 2; c++)
         {
             x->block[20 + r*2+c].src_diff = x->src_diff + 320 + r * 4 * 8 + c * 4;
         }
     }
     x->block[24].src_diff = x->src_diff + 384;
     for (i = 0; i < 25; i++)
     {
         x->block[i].coeff = x->coeff + i * 16;
     }
 }
 void vp8_build_block_offsets(MACROBLOCK *x)
 {
     int block = 0;
     int br, bc;
     vp8_build_block_doffsets(&x->e_mbd);
     /* y blocks */
     x->thismb_ptr = &x->thismb[0];
     for (br = 0; br < 4; br++)
     {
         for (bc = 0; bc < 4; bc++)
         {
             BLOCK *this_block = &x->block[block];
             this_block->base_src = &x->thismb_ptr;
             this_block->src_stride = 16;
             this_block->src = 4 * br * 16 + 4 * bc;
             ++block;
         }
     }
     /* u blocks */
     for (br = 0; br < 2; br++)
     {
         for (bc = 0; bc < 2; bc++)
         {
             BLOCK *this_block = &x->block[block];
             this_block->base_src = &x->src.u_buffer;
             this_block->src_stride = x->src.uv_stride;
             this_block->src = 4 * br * this_block->src_stride + 4 * bc;
             ++block;
         }
     }
     /* v blocks */
     for (br = 0; br < 2; br++)
     {
         for (bc = 0; bc < 2; bc++)
         {
             BLOCK *this_block = &x->block[block];
             this_block->base_src = &x->src.v_buffer;
             this_block->src_stride = x->src.uv_stride;
             this_block->src = 4 * br * this_block->src_stride + 4 * bc;
             ++block;
         }
     }
 }
 static void sum_intra_stats(VP8_COMP *cpi, MACROBLOCK *x)
 {
     const MACROBLOCKD *xd = & x->e_mbd;
     const MB_PREDICTION_MODE m = xd->mode_info_context->mbmi.mode;
     const MB_PREDICTION_MODE uvm = xd->mode_info_context->mbmi.uv_mode;
 #ifdef MODE_STATS
     const int is_key = cpi->common.frame_type == KEY_FRAME;
     ++ (is_key ? uv_modes : inter_uv_modes)[uvm];
     if (m == B_PRED)
     {
         unsigned int *const bct = is_key ? b_modes : inter_b_modes;
         int b = 0;
         do
         {
             ++ bct[xd->block[b].bmi.mode];
         }
         while (++b < 16);
     }
 #endif
     ++x->ymode_count[m];
     ++x->uv_mode_count[uvm];
 }
 /* Experimental stub function to create a per MB zbin adjustment based on
  * some previously calculated measure of MB activity.
  */
 static void adjust_act_zbin( VP8_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
 }
 int vp8cx_encode_intra_macroblock(VP8_COMP *cpi, MACROBLOCK *x,
                                   TOKENEXTRA **t)
 {
     MACROBLOCKD *xd = &x->e_mbd;
     int rate;
     if (cpi->sf.RD && cpi->compressor_speed != 2)
         vp8_rd_pick_intra_mode(x, &rate);
     else
         vp8_pick_intra_mode(x, &rate);
     if(cpi->oxcf.tuning == VP8_TUNE_SSIM)
     {
         adjust_act_zbin( cpi, x );
         vp8_update_zbin_extra(cpi, x);
     }
     if (x->e_mbd.mode_info_context->mbmi.mode == B_PRED)
         vp8_encode_intra4x4mby(x);
     else
         vp8_encode_intra16x16mby(x);
     vp8_encode_intra16x16mbuv(x);
     sum_intra_stats(cpi, x);
     vp8_tokenize_mb(cpi, x, t);
     if (xd->mode_info_context->mbmi.mode != B_PRED)
         vp8_inverse_transform_mby(xd);
     vp8_dequant_idct_add_uv_block
                     (xd->qcoeff+16*16, xd->dequant_uv,
                      xd->dst.u_buffer, xd->dst.v_buffer,
                      xd->dst.uv_stride, xd->eobs+16);
     return rate;
 }
 #ifdef SPEEDSTATS
 extern int cnt_pm;
 #endif
 extern void vp8_fix_contexts(MACROBLOCKD *x);
 int vp8cx_encode_inter_macroblock
 (
     VP8_COMP *cpi, MACROBLOCK *x, TOKENEXTRA **t,
     int recon_yoffset, int recon_uvoffset,
     int mb_row, int mb_col
 )
 {
     MACROBLOCKD *const xd = &x->e_mbd;
     int intra_error = 0;
     int rate;
     int distortion;
     x->skip = 0;
     if (xd->segmentation_enabled)
         x->encode_breakout = cpi->segment_encode_breakout[xd->mode_info_context->mbmi.segment_id];
     else
         x->encode_breakout = cpi->oxcf.encode_breakout;
 #if CONFIG_TEMPORAL_DENOISING
     /* Reset the best sse mode/mv for each macroblock. */
     x->best_reference_frame = INTRA_FRAME;
     x->best_zeromv_reference_frame = INTRA_FRAME;
     x->best_sse_inter_mode = 0;
     x->best_sse_mv.as_int = 0;
     x->need_to_clamp_best_mvs = 0;
 #endif
     if (cpi->sf.RD)
     {
         int zbin_mode_boost_enabled = x->zbin_mode_boost_enabled;
         /* Are we using the fast quantizer for the mode selection? */
         if(cpi->sf.use_fastquant_for_pick)
         {
             x->quantize_b      = vp8_fast_quantize_b;
             x->quantize_b_pair = vp8_fast_quantize_b_pair;
             /* the fast quantizer does not use zbin_extra, so
              * do not recalculate */
             x->zbin_mode_boost_enabled = 0;
         }
         vp8_rd_pick_inter_mode(cpi, x, recon_yoffset, recon_uvoffset, &rate,
                                &distortion, &intra_error);
         /* switch back to the regular quantizer for the encode */
         if (cpi->sf.improved_quant)
         {
             x->quantize_b      = vp8_regular_quantize_b;
             x->quantize_b_pair = vp8_regular_quantize_b_pair;
         }
         /* restore cpi->zbin_mode_boost_enabled */
         x->zbin_mode_boost_enabled = zbin_mode_boost_enabled;
     }
     else
     {
         vp8_pick_inter_mode(cpi, x, recon_yoffset, recon_uvoffset, &rate,
                             &distortion, &intra_error, mb_row, mb_col);
     }
     x->prediction_error += distortion;
     x->intra_error += intra_error;
     if(cpi->oxcf.tuning == VP8_TUNE_SSIM)
     {
         /* Adjust the zbin based on this MB rate. */
         adjust_act_zbin( cpi, x );
     }
 #if 0
     /* Experimental RD code */
     cpi->frame_distortion += distortion;
     cpi->last_mb_distortion = distortion;
 #endif
     /* MB level adjutment to quantizer setup */
     if (xd->segmentation_enabled)
     {
         /* If cyclic update enabled */
         if (cpi->current_layer == 0 && cpi->cyclic_refresh_mode_enabled)
         {
             /* Clear segment_id back to 0 if not coded (last frame 0,0) */
             if ((xd->mode_info_context->mbmi.segment_id == 1) &&
                 ((xd->mode_info_context->mbmi.ref_frame != LAST_FRAME) || (xd->mode_info_context->mbmi.mode != ZEROMV)))
             {
                 xd->mode_info_context->mbmi.segment_id = 0;
                 /* segment_id changed, so update */
                 vp8cx_mb_init_quantizer(cpi, x, 1);
             }
         }
     }
     {
         /* Experimental code.
          * Special case for gf and arf zeromv modes, for 1 temporal layer.
          * Increase zbin size to supress noise.
          */
         x->zbin_mode_boost = 0;
         if (x->zbin_mode_boost_enabled)
         {
             if ( xd->mode_info_context->mbmi.ref_frame != INTRA_FRAME )
             {
                 if (xd->mode_info_context->mbmi.mode == ZEROMV)
                 {
                     if (xd->mode_info_context->mbmi.ref_frame != LAST_FRAME &&
                         cpi->oxcf.number_of_layers == 1)
                         x->zbin_mode_boost = GF_ZEROMV_ZBIN_BOOST;
                     else
                         x->zbin_mode_boost = LF_ZEROMV_ZBIN_BOOST;
                 }
                 else if (xd->mode_info_context->mbmi.mode == SPLITMV)
                     x->zbin_mode_boost = 0;
                 else
                     x->zbin_mode_boost = MV_ZBIN_BOOST;
             }
         }
         /* The fast quantizer doesn't use zbin_extra, only do so with
          * the regular quantizer. */
         if (cpi->sf.improved_quant)
             vp8_update_zbin_extra(cpi, x);
     }
     x->count_mb_ref_frame_usage[xd->mode_info_context->mbmi.ref_frame] ++;
     if (xd->mode_info_context->mbmi.ref_frame == INTRA_FRAME)
     {
         vp8_encode_intra16x16mbuv(x);
         if (xd->mode_info_context->mbmi.mode == B_PRED)
         {
             vp8_encode_intra4x4mby(x);
         }
         else
         {
             vp8_encode_intra16x16mby(x);
         }
         sum_intra_stats(cpi, x);
     }
     else
     {
         int ref_fb_idx;
         if (xd->mode_info_context->mbmi.ref_frame == LAST_FRAME)
             ref_fb_idx = cpi->common.lst_fb_idx;
         else if (xd->mode_info_context->mbmi.ref_frame == GOLDEN_FRAME)
             ref_fb_idx = cpi->common.gld_fb_idx;
         else
             ref_fb_idx = cpi->common.alt_fb_idx;
         xd->pre.y_buffer = cpi->common.yv12_fb[ref_fb_idx].y_buffer + recon_yoffset;
         xd->pre.u_buffer = cpi->common.yv12_fb[ref_fb_idx].u_buffer + recon_uvoffset;
         xd->pre.v_buffer = cpi->common.yv12_fb[ref_fb_idx].v_buffer + recon_uvoffset;
         if (!x->skip)
         {
             vp8_encode_inter16x16(x);
         }
         else
             vp8_build_inter16x16_predictors_mb(xd, xd->dst.y_buffer,
                                            xd->dst.u_buffer, xd->dst.v_buffer,
                                            xd->dst.y_stride, xd->dst.uv_stride);
     }
     if (!x->skip)
     {
         vp8_tokenize_mb(cpi, x, t);
         if (xd->mode_info_context->mbmi.mode != B_PRED)
             vp8_inverse_transform_mby(xd);
         vp8_dequant_idct_add_uv_block
                         (xd->qcoeff+16*16, xd->dequant_uv,
                          xd->dst.u_buffer, xd->dst.v_buffer,
                          xd->dst.uv_stride, xd->eobs+16);
     }
     else
     {
         /* always set mb_skip_coeff as it is needed by the loopfilter */
         xd->mode_info_context->mbmi.mb_skip_coeff = 1;
         if (cpi->common.mb_no_coeff_skip)
         {
             x->skip_true_count ++;
             vp8_fix_contexts(xd);
         }
         else
         {
             vp8_stuff_mb(cpi, x, t);
         }
     }
     return rate;
 }

The Tor Browser / annotate

media/libvpx/vp8/encoder/encodeframe.c@b8a032363ba2 (annotated)

media/libvpx/vp8/encoder/encodeframe.c