falkTX
/
FFmpeg
mirror of https://github.com/falkTX/FFmpeg.git
1
0
Fork 0
Code Issues 0 Releases 338 Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
74465 Commits
32 Branches
290MB
Tree: 1907e19d0c
Branches Tags
${ item.name }
Create branch ${ searchTerm }
from '1907e19d0c'
${ noResults }
FFmpeg/libavcodec/vc1_pred.c

941 lines
37KB
Raw Blame History 

  1. /*

  2.  * VC-1 and WMV3 decoder

  3.  * Copyright (c) 2011 Mashiat Sarker Shakkhar

  4.  * Copyright (c) 2006-2007 Konstantin Shishkov

  5.  * Partly based on vc9.c (c) 2005 Anonymous, Alex Beregszaszi, Michael Niedermayer

  6.  *

  7.  * This file is part of FFmpeg.

  8.  *

  9.  * FFmpeg is free software; you can redistribute it and/or

  10.  * modify it under the terms of the GNU Lesser General Public

  11.  * License as published by the Free Software Foundation; either

  12.  * version 2.1 of the License, or (at your option) any later version.

  13.  *

  14.  * FFmpeg is distributed in the hope that it will be useful,

  15.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  16.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  17.  * Lesser General Public License for more details.

  18.  *

  19.  * You should have received a copy of the GNU Lesser General Public

  20.  * License along with FFmpeg; if not, write to the Free Software

  21.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  22.  */

  23. 

  24. /**

  25.  * @file

  26.  * VC-1 and WMV3 block decoding routines

  27.  */

  28. 

  29. #include "mathops.h"

  30. #include "mpegutils.h"

  31. #include "mpegvideo.h"

  32. #include "vc1.h"

  33. #include "vc1_pred.h"

  34. #include "vc1data.h"

  35. 

  36. static av_always_inline int scaleforsame_x(VC1Context *v, int n /* MV */, int dir)

  37. {

  38.     int scaledvalue, refdist;

  39.     int scalesame1, scalesame2;

  40.     int scalezone1_x, zone1offset_x;

  41.     int table_index = dir ^ v->second_field;

  42. 

  43.     if (v->s.pict_type != AV_PICTURE_TYPE_B)

  44.         refdist = v->refdist;

  45.     else

  46.         refdist = dir ? v->brfd : v->frfd;

  47.     if (refdist > 3)

  48.         refdist = 3;

  49.     scalesame1    = ff_vc1_field_mvpred_scales[table_index][1][refdist];

  50.     scalesame2    = ff_vc1_field_mvpred_scales[table_index][2][refdist];

  51.     scalezone1_x  = ff_vc1_field_mvpred_scales[table_index][3][refdist];

  52.     zone1offset_x = ff_vc1_field_mvpred_scales[table_index][5][refdist];

  53. 

  54.     if (FFABS(n) > 255)

  55.         scaledvalue = n;

  56.     else {

  57.         if (FFABS(n) < scalezone1_x)

  58.             scaledvalue = (n * scalesame1) >> 8;

  59.         else {

  60.             if (n < 0)

  61.                 scaledvalue = ((n * scalesame2) >> 8) - zone1offset_x;

  62.             else

  63.                 scaledvalue = ((n * scalesame2) >> 8) + zone1offset_x;

  64.         }

  65.     }

  66.     return av_clip(scaledvalue, -v->range_x, v->range_x - 1);

  67. }

  68. 

  69. static av_always_inline int scaleforsame_y(VC1Context *v, int i, int n /* MV */, int dir)

  70. {

  71.     int scaledvalue, refdist;

  72.     int scalesame1, scalesame2;

  73.     int scalezone1_y, zone1offset_y;

  74.     int table_index = dir ^ v->second_field;

  75. 

  76.     if (v->s.pict_type != AV_PICTURE_TYPE_B)

  77.         refdist = v->refdist;

  78.     else

  79.         refdist = dir ? v->brfd : v->frfd;

  80.     if (refdist > 3)

  81.         refdist = 3;

  82.     scalesame1    = ff_vc1_field_mvpred_scales[table_index][1][refdist];

  83.     scalesame2    = ff_vc1_field_mvpred_scales[table_index][2][refdist];

  84.     scalezone1_y  = ff_vc1_field_mvpred_scales[table_index][4][refdist];

  85.     zone1offset_y = ff_vc1_field_mvpred_scales[table_index][6][refdist];

  86. 

  87.     if (FFABS(n) > 63)

  88.         scaledvalue = n;

  89.     else {

  90.         if (FFABS(n) < scalezone1_y)

  91.             scaledvalue = (n * scalesame1) >> 8;

  92.         else {

  93.             if (n < 0)

  94.                 scaledvalue = ((n * scalesame2) >> 8) - zone1offset_y;

  95.             else

  96.                 scaledvalue = ((n * scalesame2) >> 8) + zone1offset_y;

  97.         }

  98.     }

  99. 

  100.     if (v->cur_field_type && !v->ref_field_type[dir])

  101.         return av_clip(scaledvalue, -v->range_y / 2 + 1, v->range_y / 2);

  102.     else

  103.         return av_clip(scaledvalue, -v->range_y / 2, v->range_y / 2 - 1);

  104. }

  105. 

  106. static av_always_inline int scaleforopp_x(VC1Context *v, int n /* MV */)

  107. {

  108.     int scalezone1_x, zone1offset_x;

  109.     int scaleopp1, scaleopp2, brfd;

  110.     int scaledvalue;

  111. 

  112.     brfd = FFMIN(v->brfd, 3);

  113.     scalezone1_x  = ff_vc1_b_field_mvpred_scales[3][brfd];

  114.     zone1offset_x = ff_vc1_b_field_mvpred_scales[5][brfd];

  115.     scaleopp1     = ff_vc1_b_field_mvpred_scales[1][brfd];

  116.     scaleopp2     = ff_vc1_b_field_mvpred_scales[2][brfd];

  117. 

  118.     if (FFABS(n) > 255)

  119.         scaledvalue = n;

  120.     else {

  121.         if (FFABS(n) < scalezone1_x)

  122.             scaledvalue = (n * scaleopp1) >> 8;

  123.         else {

  124.             if (n < 0)

  125.                 scaledvalue = ((n * scaleopp2) >> 8) - zone1offset_x;

  126.             else

  127.                 scaledvalue = ((n * scaleopp2) >> 8) + zone1offset_x;

  128.         }

  129.     }

  130.     return av_clip(scaledvalue, -v->range_x, v->range_x - 1);

  131. }

  132. 

  133. static av_always_inline int scaleforopp_y(VC1Context *v, int n /* MV */, int dir)

  134. {

  135.     int scalezone1_y, zone1offset_y;

  136.     int scaleopp1, scaleopp2, brfd;

  137.     int scaledvalue;

  138. 

  139.     brfd = FFMIN(v->brfd, 3);

  140.     scalezone1_y  = ff_vc1_b_field_mvpred_scales[4][brfd];

  141.     zone1offset_y = ff_vc1_b_field_mvpred_scales[6][brfd];

  142.     scaleopp1     = ff_vc1_b_field_mvpred_scales[1][brfd];

  143.     scaleopp2     = ff_vc1_b_field_mvpred_scales[2][brfd];

  144. 

  145.     if (FFABS(n) > 63)

  146.         scaledvalue = n;

  147.     else {

  148.         if (FFABS(n) < scalezone1_y)

  149.             scaledvalue = (n * scaleopp1) >> 8;

  150.         else {

  151.             if (n < 0)

  152.                 scaledvalue = ((n * scaleopp2) >> 8) - zone1offset_y;

  153.             else

  154.                 scaledvalue = ((n * scaleopp2) >> 8) + zone1offset_y;

  155.         }

  156.     }

  157.     if (v->cur_field_type && !v->ref_field_type[dir]) {

  158.         return av_clip(scaledvalue, -v->range_y / 2 + 1, v->range_y / 2);

  159.     } else {

  160.         return av_clip(scaledvalue, -v->range_y / 2, v->range_y / 2 - 1);

  161.     }

  162. }

  163. 

  164. static av_always_inline int scaleforsame(VC1Context *v, int i, int n /* MV */,

  165.                                          int dim, int dir)

  166. {

  167.     int brfd, scalesame;

  168.     int hpel = 1 - v->s.quarter_sample;

  169. 

  170.     n >>= hpel;

  171.     if (v->s.pict_type != AV_PICTURE_TYPE_B || v->second_field || !dir) {

  172.         if (dim)

  173.             n = scaleforsame_y(v, i, n, dir) * (1 << hpel);

  174.         else

  175.             n = scaleforsame_x(v, n, dir) * (1 << hpel);

  176.         return n;

  177.     }

  178.     brfd      = FFMIN(v->brfd, 3);

  179.     scalesame = ff_vc1_b_field_mvpred_scales[0][brfd];

  180. 

  181.     n = (n * scalesame >> 8) << hpel;

  182.     return n;

  183. }

  184. 

  185. static av_always_inline int scaleforopp(VC1Context *v, int n /* MV */,

  186.                                         int dim, int dir)

  187. {

  188.     int refdist, scaleopp;

  189.     int hpel = 1 - v->s.quarter_sample;

  190. 

  191.     n >>= hpel;

  192.     if (v->s.pict_type == AV_PICTURE_TYPE_B && !v->second_field && dir == 1) {

  193.         if (dim)

  194.             n = scaleforopp_y(v, n, dir) << hpel;

  195.         else

  196.             n = scaleforopp_x(v, n) << hpel;

  197.         return n;

  198.     }

  199.     if (v->s.pict_type != AV_PICTURE_TYPE_B)

  200.         refdist = FFMIN(v->refdist, 3);

  201.     else

  202.         refdist = dir ? v->brfd : v->frfd;

  203.     scaleopp = ff_vc1_field_mvpred_scales[dir ^ v->second_field][0][refdist];

  204. 

  205.     n = (n * scaleopp >> 8) * (1 << hpel);

  206.     return n;

  207. }

  208. 

  209. /** Predict and set motion vector

  210.  */

  211. void ff_vc1_pred_mv(VC1Context *v, int n, int dmv_x, int dmv_y,

  212.                     int mv1, int r_x, int r_y, uint8_t* is_intra,

  213.                     int pred_flag, int dir)

  214. {

  215.     MpegEncContext *s = &v->s;

  216.     int xy, wrap, off = 0;

  217.     int16_t *A, *B, *C;

  218.     int px, py;

  219.     int sum;

  220.     int mixedmv_pic, num_samefield = 0, num_oppfield = 0;

  221.     int opposite, a_f, b_f, c_f;

  222.     int16_t field_predA[2];

  223.     int16_t field_predB[2];

  224.     int16_t field_predC[2];

  225.     int a_valid, b_valid, c_valid;

  226.     int hybridmv_thresh, y_bias = 0;

  227. 

  228.     if (v->mv_mode == MV_PMODE_MIXED_MV ||

  229.         ((v->mv_mode == MV_PMODE_INTENSITY_COMP) && (v->mv_mode2 == MV_PMODE_MIXED_MV)))

  230.         mixedmv_pic = 1;

  231.     else

  232.         mixedmv_pic = 0;

  233.     /* scale MV difference to be quad-pel */

  234.     if (!s->quarter_sample) {

  235.         dmv_x *= 2;

  236.         dmv_y *= 2;

  237.     }

  238. 

  239.     wrap = s->b8_stride;

  240.     xy   = s->block_index[n];

  241. 

  242.     if (s->mb_intra) {

  243.         s->mv[0][n][0] = s->current_picture.motion_val[0][xy + v->blocks_off][0] = 0;

  244.         s->mv[0][n][1] = s->current_picture.motion_val[0][xy + v->blocks_off][1] = 0;

  245.         s->current_picture.motion_val[1][xy + v->blocks_off][0] = 0;

  246.         s->current_picture.motion_val[1][xy + v->blocks_off][1] = 0;

  247.         if (mv1) { /* duplicate motion data for 1-MV block */

  248.             s->current_picture.motion_val[0][xy + 1 + v->blocks_off][0]        = 0;

  249.             s->current_picture.motion_val[0][xy + 1 + v->blocks_off][1]        = 0;

  250.             s->current_picture.motion_val[0][xy + wrap + v->blocks_off][0]     = 0;

  251.             s->current_picture.motion_val[0][xy + wrap + v->blocks_off][1]     = 0;

  252.             s->current_picture.motion_val[0][xy + wrap + 1 + v->blocks_off][0] = 0;

  253.             s->current_picture.motion_val[0][xy + wrap + 1 + v->blocks_off][1] = 0;

  254.             v->luma_mv[s->mb_x][0] = v->luma_mv[s->mb_x][1] = 0;

  255.             s->current_picture.motion_val[1][xy + 1 + v->blocks_off][0]        = 0;

  256.             s->current_picture.motion_val[1][xy + 1 + v->blocks_off][1]        = 0;

  257.             s->current_picture.motion_val[1][xy + wrap][0]                     = 0;

  258.             s->current_picture.motion_val[1][xy + wrap + v->blocks_off][1]     = 0;

  259.             s->current_picture.motion_val[1][xy + wrap + 1 + v->blocks_off][0] = 0;

  260.             s->current_picture.motion_val[1][xy + wrap + 1 + v->blocks_off][1] = 0;

  261.         }

  262.         return;

  263.     }

  264. 

  265.     C = s->current_picture.motion_val[dir][xy -    1 + v->blocks_off];

  266.     A = s->current_picture.motion_val[dir][xy - wrap + v->blocks_off];

  267.     if (mv1) {

  268.         if (v->field_mode && mixedmv_pic)

  269.             off = (s->mb_x == (s->mb_width - 1)) ? -2 : 2;

  270.         else

  271.             off = (s->mb_x == (s->mb_width - 1)) ? -1 : 2;

  272.     } else {

  273.         //in 4-MV mode different blocks have different B predictor position

  274.         switch (n) {

  275.         case 0:

  276.             off = (s->mb_x > 0) ? -1 : 1;

  277.             break;

  278.         case 1:

  279.             off = (s->mb_x == (s->mb_width - 1)) ? -1 : 1;

  280.             break;

  281.         case 2:

  282.             off = 1;

  283.             break;

  284.         case 3:

  285.             off = -1;

  286.         }

  287.     }

  288.     B = s->current_picture.motion_val[dir][xy - wrap + off + v->blocks_off];

  289. 

  290.     a_valid = !s->first_slice_line || (n == 2 || n == 3);

  291.     b_valid = a_valid && (s->mb_width > 1);

  292.     c_valid = s->mb_x || (n == 1 || n == 3);

  293.     if (v->field_mode) {

  294.         a_valid = a_valid && !is_intra[xy - wrap];

  295.         b_valid = b_valid && !is_intra[xy - wrap + off];

  296.         c_valid = c_valid && !is_intra[xy - 1];

  297.     }

  298. 

  299.     if (a_valid) {

  300.         a_f = v->mv_f[dir][xy - wrap + v->blocks_off];

  301.         num_oppfield  += a_f;

  302.         num_samefield += 1 - a_f;

  303.         field_predA[0] = A[0];

  304.         field_predA[1] = A[1];

  305.     } else {

  306.         field_predA[0] = field_predA[1] = 0;

  307.         a_f = 0;

  308.     }

  309.     if (b_valid) {

  310.         b_f = v->mv_f[dir][xy - wrap + off + v->blocks_off];

  311.         num_oppfield  += b_f;

  312.         num_samefield += 1 - b_f;

  313.         field_predB[0] = B[0];

  314.         field_predB[1] = B[1];

  315.     } else {

  316.         field_predB[0] = field_predB[1] = 0;

  317.         b_f = 0;

  318.     }

  319.     if (c_valid) {

  320.         c_f = v->mv_f[dir][xy - 1 + v->blocks_off];

  321.         num_oppfield  += c_f;

  322.         num_samefield += 1 - c_f;

  323.         field_predC[0] = C[0];

  324.         field_predC[1] = C[1];

  325.     } else {

  326.         field_predC[0] = field_predC[1] = 0;

  327.         c_f = 0;

  328.     }

  329. 

  330.     if (v->field_mode) {

  331.         if (!v->numref)

  332.             // REFFIELD determines if the last field or the second-last field is

  333.             // to be used as reference

  334.             opposite = 1 - v->reffield;

  335.         else {

  336.             if (num_samefield <= num_oppfield)

  337.                 opposite = 1 - pred_flag;

  338.             else

  339.                 opposite = pred_flag;

  340.         }

  341.     } else

  342.         opposite = 0;

  343.     if (opposite) {

  344.         if (a_valid && !a_f) {

  345.             field_predA[0] = scaleforopp(v, field_predA[0], 0, dir);

  346.             field_predA[1] = scaleforopp(v, field_predA[1], 1, dir);

  347.         }

  348.         if (b_valid && !b_f) {

  349.             field_predB[0] = scaleforopp(v, field_predB[0], 0, dir);

  350.             field_predB[1] = scaleforopp(v, field_predB[1], 1, dir);

  351.         }

  352.         if (c_valid && !c_f) {

  353.             field_predC[0] = scaleforopp(v, field_predC[0], 0, dir);

  354.             field_predC[1] = scaleforopp(v, field_predC[1], 1, dir);

  355.         }

  356.         v->mv_f[dir][xy + v->blocks_off] = 1;

  357.         v->ref_field_type[dir] = !v->cur_field_type;

  358.     } else {

  359.         if (a_valid && a_f) {

  360.             field_predA[0] = scaleforsame(v, n, field_predA[0], 0, dir);

  361.             field_predA[1] = scaleforsame(v, n, field_predA[1], 1, dir);

  362.         }

  363.         if (b_valid && b_f) {

  364.             field_predB[0] = scaleforsame(v, n, field_predB[0], 0, dir);

  365.             field_predB[1] = scaleforsame(v, n, field_predB[1], 1, dir);

  366.         }

  367.         if (c_valid && c_f) {

  368.             field_predC[0] = scaleforsame(v, n, field_predC[0], 0, dir);

  369.             field_predC[1] = scaleforsame(v, n, field_predC[1], 1, dir);

  370.         }

  371.         v->mv_f[dir][xy + v->blocks_off] = 0;

  372.         v->ref_field_type[dir] = v->cur_field_type;

  373.     }

  374. 

  375.     if (a_valid) {

  376.         px = field_predA[0];

  377.         py = field_predA[1];

  378.     } else if (c_valid) {

  379.         px = field_predC[0];

  380.         py = field_predC[1];

  381.     } else if (b_valid) {

  382.         px = field_predB[0];

  383.         py = field_predB[1];

  384.     } else {

  385.         px = 0;

  386.         py = 0;

  387.     }

  388. 

  389.     if (num_samefield + num_oppfield > 1) {

  390.         px = mid_pred(field_predA[0], field_predB[0], field_predC[0]);

  391.         py = mid_pred(field_predA[1], field_predB[1], field_predC[1]);

  392.     }

  393. 

  394.     /* Pullback MV as specified in 8.3.5.3.4 */

  395.     if (!v->field_mode) {

  396.         int qx, qy, X, Y;

  397.         int MV = mv1 ? -60 : -28;

  398.         qx = (s->mb_x << 6) + ((n == 1 || n == 3) ? 32 : 0);

  399.         qy = (s->mb_y << 6) + ((n == 2 || n == 3) ? 32 : 0);

  400.         X  = (s->mb_width  << 6) - 4;

  401.         Y  = (s->mb_height << 6) - 4;

  402.         if (qx + px < MV) px = MV - qx;

  403.         if (qy + py < MV) py = MV - qy;

  404.         if (qx + px > X) px = X - qx;

  405.         if (qy + py > Y) py = Y - qy;

  406.     }

  407. 

  408.     if (!v->field_mode || s->pict_type != AV_PICTURE_TYPE_B) {

  409.         /* Calculate hybrid prediction as specified in 8.3.5.3.5 (also 10.3.5.4.3.5) */

  410.         hybridmv_thresh = 32;

  411.         if (a_valid && c_valid) {

  412.             if (is_intra[xy - wrap])

  413.                 sum = FFABS(px) + FFABS(py);

  414.             else

  415.                 sum = FFABS(px - field_predA[0]) + FFABS(py - field_predA[1]);

  416.             if (sum > hybridmv_thresh) {

  417.                 if (get_bits1(&s->gb)) {     // read HYBRIDPRED bit

  418.                     px = field_predA[0];

  419.                     py = field_predA[1];

  420.                 } else {

  421.                     px = field_predC[0];

  422.                     py = field_predC[1];

  423.                 }

  424.             } else {

  425.                 if (is_intra[xy - 1])

  426.                     sum = FFABS(px) + FFABS(py);

  427.                 else

  428.                     sum = FFABS(px - field_predC[0]) + FFABS(py - field_predC[1]);

  429.                 if (sum > hybridmv_thresh) {

  430.                     if (get_bits1(&s->gb)) {

  431.                         px = field_predA[0];

  432.                         py = field_predA[1];

  433.                     } else {

  434.                         px = field_predC[0];

  435.                         py = field_predC[1];

  436.                     }

  437.                 }

  438.             }

  439.         }

  440.     }

  441. 

  442.     if (v->field_mode && v->numref)

  443.         r_y >>= 1;

  444.     if (v->field_mode && v->cur_field_type && v->ref_field_type[dir] == 0)

  445.         y_bias = 1;

  446.     /* store MV using signed modulus of MV range defined in 4.11 */

  447.     s->mv[dir][n][0] = s->current_picture.motion_val[dir][xy + v->blocks_off][0] = ((px + dmv_x + r_x) & ((r_x << 1) - 1)) - r_x;

  448.     s->mv[dir][n][1] = s->current_picture.motion_val[dir][xy + v->blocks_off][1] = ((py + dmv_y + r_y - y_bias) & ((r_y << 1) - 1)) - r_y + y_bias;

  449.     if (mv1) { /* duplicate motion data for 1-MV block */

  450.         s->current_picture.motion_val[dir][xy +    1 +     v->blocks_off][0] = s->current_picture.motion_val[dir][xy + v->blocks_off][0];

  451.         s->current_picture.motion_val[dir][xy +    1 +     v->blocks_off][1] = s->current_picture.motion_val[dir][xy + v->blocks_off][1];

  452.         s->current_picture.motion_val[dir][xy + wrap +     v->blocks_off][0] = s->current_picture.motion_val[dir][xy + v->blocks_off][0];

  453.         s->current_picture.motion_val[dir][xy + wrap +     v->blocks_off][1] = s->current_picture.motion_val[dir][xy + v->blocks_off][1];

  454.         s->current_picture.motion_val[dir][xy + wrap + 1 + v->blocks_off][0] = s->current_picture.motion_val[dir][xy + v->blocks_off][0];

  455.         s->current_picture.motion_val[dir][xy + wrap + 1 + v->blocks_off][1] = s->current_picture.motion_val[dir][xy + v->blocks_off][1];

  456.         v->mv_f[dir][xy +    1 + v->blocks_off] = v->mv_f[dir][xy +            v->blocks_off];

  457.         v->mv_f[dir][xy + wrap + v->blocks_off] = v->mv_f[dir][xy + wrap + 1 + v->blocks_off] = v->mv_f[dir][xy + v->blocks_off];

  458.     }

  459. }

  460. 

  461. /** Predict and set motion vector for interlaced frame picture MBs

  462.  */

  463. void ff_vc1_pred_mv_intfr(VC1Context *v, int n, int dmv_x, int dmv_y,

  464.                           int mvn, int r_x, int r_y, uint8_t* is_intra, int dir)

  465. {

  466.     MpegEncContext *s = &v->s;

  467.     int xy, wrap, off = 0;

  468.     int A[2], B[2], C[2];

  469.     int px = 0, py = 0;

  470.     int a_valid = 0, b_valid = 0, c_valid = 0;

  471.     int field_a, field_b, field_c; // 0: same, 1: opposit

  472.     int total_valid, num_samefield, num_oppfield;

  473.     int pos_c, pos_b, n_adj;

  474. 

  475.     wrap = s->b8_stride;

  476.     xy = s->block_index[n];

  477. 

  478.     if (s->mb_intra) {

  479.         s->mv[0][n][0] = s->current_picture.motion_val[0][xy][0] = 0;

  480.         s->mv[0][n][1] = s->current_picture.motion_val[0][xy][1] = 0;

  481.         s->current_picture.motion_val[1][xy][0] = 0;

  482.         s->current_picture.motion_val[1][xy][1] = 0;

  483.         if (mvn == 1) { /* duplicate motion data for 1-MV block */

  484.             s->current_picture.motion_val[0][xy + 1][0]        = 0;

  485.             s->current_picture.motion_val[0][xy + 1][1]        = 0;

  486.             s->current_picture.motion_val[0][xy + wrap][0]     = 0;

  487.             s->current_picture.motion_val[0][xy + wrap][1]     = 0;

  488.             s->current_picture.motion_val[0][xy + wrap + 1][0] = 0;

  489.             s->current_picture.motion_val[0][xy + wrap + 1][1] = 0;

  490.             v->luma_mv[s->mb_x][0] = v->luma_mv[s->mb_x][1] = 0;

  491.             s->current_picture.motion_val[1][xy + 1][0]        = 0;

  492.             s->current_picture.motion_val[1][xy + 1][1]        = 0;

  493.             s->current_picture.motion_val[1][xy + wrap][0]     = 0;

  494.             s->current_picture.motion_val[1][xy + wrap][1]     = 0;

  495.             s->current_picture.motion_val[1][xy + wrap + 1][0] = 0;

  496.             s->current_picture.motion_val[1][xy + wrap + 1][1] = 0;

  497.         }

  498.         return;

  499.     }

  500. 

  501.     off = ((n == 0) || (n == 1)) ? 1 : -1;

  502.     /* predict A */

  503.     if (s->mb_x || (n == 1) || (n == 3)) {

  504.         if ((v->blk_mv_type[xy]) // current block (MB) has a field MV

  505.             || (!v->blk_mv_type[xy] && !v->blk_mv_type[xy - 1])) { // or both have frame MV

  506.             A[0] = s->current_picture.motion_val[dir][xy - 1][0];

  507.             A[1] = s->current_picture.motion_val[dir][xy - 1][1];

  508.             a_valid = 1;

  509.         } else { // current block has frame mv and cand. has field MV (so average)

  510.             A[0] = (s->current_picture.motion_val[dir][xy - 1][0]

  511.                     + s->current_picture.motion_val[dir][xy - 1 + off * wrap][0] + 1) >> 1;

  512.             A[1] = (s->current_picture.motion_val[dir][xy - 1][1]

  513.                     + s->current_picture.motion_val[dir][xy - 1 + off * wrap][1] + 1) >> 1;

  514.             a_valid = 1;

  515.         }

  516.         if (!(n & 1) && v->is_intra[s->mb_x - 1]) {

  517.             a_valid = 0;

  518.             A[0] = A[1] = 0;

  519.         }

  520.     } else

  521.         A[0] = A[1] = 0;

  522.     /* Predict B and C */

  523.     B[0] = B[1] = C[0] = C[1] = 0;

  524.     if (n == 0 || n == 1 || v->blk_mv_type[xy]) {

  525.         if (!s->first_slice_line) {

  526.             if (!v->is_intra[s->mb_x - s->mb_stride]) {

  527.                 b_valid = 1;

  528.                 n_adj   = n | 2;

  529.                 pos_b   = s->block_index[n_adj] - 2 * wrap;

  530.                 if (v->blk_mv_type[pos_b] && v->blk_mv_type[xy]) {

  531.                     n_adj = (n & 2) | (n & 1);

  532.                 }

  533.                 B[0] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap][0];

  534.                 B[1] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap][1];

  535.                 if (v->blk_mv_type[pos_b] && !v->blk_mv_type[xy]) {

  536.                     B[0] = (B[0] + s->current_picture.motion_val[dir][s->block_index[n_adj ^ 2] - 2 * wrap][0] + 1) >> 1;

  537.                     B[1] = (B[1] + s->current_picture.motion_val[dir][s->block_index[n_adj ^ 2] - 2 * wrap][1] + 1) >> 1;

  538.                 }

  539.             }

  540.             if (s->mb_width > 1) {

  541.                 if (!v->is_intra[s->mb_x - s->mb_stride + 1]) {

  542.                     c_valid = 1;

  543.                     n_adj   = 2;

  544.                     pos_c   = s->block_index[2] - 2 * wrap + 2;

  545.                     if (v->blk_mv_type[pos_c] && v->blk_mv_type[xy]) {

  546.                         n_adj = n & 2;

  547.                     }

  548.                     C[0] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap + 2][0];

  549.                     C[1] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap + 2][1];

  550.                     if (v->blk_mv_type[pos_c] && !v->blk_mv_type[xy]) {

  551.                         C[0] = (1 + C[0] + (s->current_picture.motion_val[dir][s->block_index[n_adj ^ 2] - 2 * wrap + 2][0])) >> 1;

  552.                         C[1] = (1 + C[1] + (s->current_picture.motion_val[dir][s->block_index[n_adj ^ 2] - 2 * wrap + 2][1])) >> 1;

  553.                     }

  554.                     if (s->mb_x == s->mb_width - 1) {

  555.                         if (!v->is_intra[s->mb_x - s->mb_stride - 1]) {

  556.                             c_valid = 1;

  557.                             n_adj   = 3;

  558.                             pos_c   = s->block_index[3] - 2 * wrap - 2;

  559.                             if (v->blk_mv_type[pos_c] && v->blk_mv_type[xy]) {

  560.                                 n_adj = n | 1;

  561.                             }

  562.                             C[0] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap - 2][0];

  563.                             C[1] = s->current_picture.motion_val[dir][s->block_index[n_adj] - 2 * wrap - 2][1];

  564.                             if (v->blk_mv_type[pos_c] && !v->blk_mv_type[xy]) {

  565.                                 C[0] = (1 + C[0] + s->current_picture.motion_val[dir][s->block_index[1] - 2 * wrap - 2][0]) >> 1;

  566.                                 C[1] = (1 + C[1] + s->current_picture.motion_val[dir][s->block_index[1] - 2 * wrap - 2][1]) >> 1;

  567.                             }

  568.                         } else

  569.                             c_valid = 0;

  570.                     }

  571.                 }

  572.             }

  573.         }

  574.     } else {

  575.         pos_b   = s->block_index[1];

  576.         b_valid = 1;

  577.         B[0]    = s->current_picture.motion_val[dir][pos_b][0];

  578.         B[1]    = s->current_picture.motion_val[dir][pos_b][1];

  579.         pos_c   = s->block_index[0];

  580.         c_valid = 1;

  581.         C[0]    = s->current_picture.motion_val[dir][pos_c][0];

  582.         C[1]    = s->current_picture.motion_val[dir][pos_c][1];

  583.     }

  584. 

  585.     total_valid = a_valid + b_valid + c_valid;

  586.     // check if predictor A is out of bounds

  587.     if (!s->mb_x && !(n == 1 || n == 3)) {

  588.         A[0] = A[1] = 0;

  589.     }

  590.     // check if predictor B is out of bounds

  591.     if ((s->first_slice_line && v->blk_mv_type[xy]) || (s->first_slice_line && !(n & 2))) {

  592.         B[0] = B[1] = C[0] = C[1] = 0;

  593.     }

  594.     if (!v->blk_mv_type[xy]) {

  595.         if (s->mb_width == 1) {

  596.             px = B[0];

  597.             py = B[1];

  598.         } else {

  599.             if (total_valid >= 2) {

  600.                 px = mid_pred(A[0], B[0], C[0]);

  601.                 py = mid_pred(A[1], B[1], C[1]);

  602.             } else if (total_valid) {

  603.                 if      (a_valid) { px = A[0]; py = A[1]; }

  604.                 else if (b_valid) { px = B[0]; py = B[1]; }

  605.                 else              { px = C[0]; py = C[1]; }

  606.             }

  607.         }

  608.     } else {

  609.         if (a_valid)

  610.             field_a = (A[1] & 4) ? 1 : 0;

  611.         else

  612.             field_a = 0;

  613.         if (b_valid)

  614.             field_b = (B[1] & 4) ? 1 : 0;

  615.         else

  616.             field_b = 0;

  617.         if (c_valid)

  618.             field_c = (C[1] & 4) ? 1 : 0;

  619.         else

  620.             field_c = 0;

  621. 

  622.         num_oppfield  = field_a + field_b + field_c;

  623.         num_samefield = total_valid - num_oppfield;

  624.         if (total_valid == 3) {

  625.             if ((num_samefield == 3) || (num_oppfield == 3)) {

  626.                 px = mid_pred(A[0], B[0], C[0]);

  627.                 py = mid_pred(A[1], B[1], C[1]);

  628.             } else if (num_samefield >= num_oppfield) {

  629.                 /* take one MV from same field set depending on priority

  630.                 the check for B may not be necessary */

  631.                 px = !field_a ? A[0] : B[0];

  632.                 py = !field_a ? A[1] : B[1];

  633.             } else {

  634.                 px =  field_a ? A[0] : B[0];

  635.                 py =  field_a ? A[1] : B[1];

  636.             }

  637.         } else if (total_valid == 2) {

  638.             if (num_samefield >= num_oppfield) {

  639.                 if (!field_a && a_valid) {

  640.                     px = A[0];

  641.                     py = A[1];

  642.                 } else if (!field_b && b_valid) {

  643.                     px = B[0];

  644.                     py = B[1];

  645.                 } else /*if (c_valid)*/ {

  646.                     av_assert1(c_valid);

  647.                     px = C[0];

  648.                     py = C[1];

  649.                 }

  650.             } else {

  651.                 if (field_a && a_valid) {

  652.                     px = A[0];

  653.                     py = A[1];

  654.                 } else /*if (field_b && b_valid)*/ {

  655.                     av_assert1(field_b && b_valid);

  656.                     px = B[0];

  657.                     py = B[1];

  658.                 }

  659.             }

  660.         } else if (total_valid == 1) {

  661.             px = (a_valid) ? A[0] : ((b_valid) ? B[0] : C[0]);

  662.             py = (a_valid) ? A[1] : ((b_valid) ? B[1] : C[1]);

  663.         }

  664.     }

  665. 

  666.     /* store MV using signed modulus of MV range defined in 4.11 */

  667.     s->mv[dir][n][0] = s->current_picture.motion_val[dir][xy][0] = ((px + dmv_x + r_x) & ((r_x << 1) - 1)) - r_x;

  668.     s->mv[dir][n][1] = s->current_picture.motion_val[dir][xy][1] = ((py + dmv_y + r_y) & ((r_y << 1) - 1)) - r_y;

  669.     if (mvn == 1) { /* duplicate motion data for 1-MV block */

  670.         s->current_picture.motion_val[dir][xy +    1    ][0] = s->current_picture.motion_val[dir][xy][0];

  671.         s->current_picture.motion_val[dir][xy +    1    ][1] = s->current_picture.motion_val[dir][xy][1];

  672.         s->current_picture.motion_val[dir][xy + wrap    ][0] = s->current_picture.motion_val[dir][xy][0];

  673.         s->current_picture.motion_val[dir][xy + wrap    ][1] = s->current_picture.motion_val[dir][xy][1];

  674.         s->current_picture.motion_val[dir][xy + wrap + 1][0] = s->current_picture.motion_val[dir][xy][0];

  675.         s->current_picture.motion_val[dir][xy + wrap + 1][1] = s->current_picture.motion_val[dir][xy][1];

  676.     } else if (mvn == 2) { /* duplicate motion data for 2-Field MV block */

  677.         s->current_picture.motion_val[dir][xy + 1][0] = s->current_picture.motion_val[dir][xy][0];

  678.         s->current_picture.motion_val[dir][xy + 1][1] = s->current_picture.motion_val[dir][xy][1];

  679.         s->mv[dir][n + 1][0] = s->mv[dir][n][0];

  680.         s->mv[dir][n + 1][1] = s->mv[dir][n][1];

  681.     }

  682. }

  683. 

  684. void ff_vc1_pred_b_mv(VC1Context *v, int dmv_x[2], int dmv_y[2],

  685.                       int direct, int mvtype)

  686. {

  687.     MpegEncContext *s = &v->s;

  688.     int xy, wrap, off = 0;

  689.     int16_t *A, *B, *C;

  690.     int px, py;

  691.     int sum;

  692.     int r_x, r_y;

  693.     const uint8_t *is_intra = v->mb_type[0];

  694. 

  695.     av_assert0(!v->field_mode);

  696. 

  697.     r_x = v->range_x;

  698.     r_y = v->range_y;

  699.     /* scale MV difference to be quad-pel */

  700.     if (!s->quarter_sample) {

  701.         dmv_x[0] *= 2;

  702.         dmv_y[0] *= 2;

  703.         dmv_x[1] *= 2;

  704.         dmv_y[1] *= 2;

  705.     }

  706. 

  707.     wrap = s->b8_stride;

  708.     xy = s->block_index[0];

  709. 

  710.     if (s->mb_intra) {

  711.         s->current_picture.motion_val[0][xy][0] =

  712.         s->current_picture.motion_val[0][xy][1] =

  713.         s->current_picture.motion_val[1][xy][0] =

  714.         s->current_picture.motion_val[1][xy][1] = 0;

  715.         return;

  716.     }

  717.         if (direct && s->next_picture_ptr->field_picture)

  718.             av_log(s->avctx, AV_LOG_WARNING, "Mixed frame/field direct mode not supported\n");

  719. 

  720.         s->mv[0][0][0] = scale_mv(s->next_picture.motion_val[1][xy][0], v->bfraction, 0, s->quarter_sample);

  721.         s->mv[0][0][1] = scale_mv(s->next_picture.motion_val[1][xy][1], v->bfraction, 0, s->quarter_sample);

  722.         s->mv[1][0][0] = scale_mv(s->next_picture.motion_val[1][xy][0], v->bfraction, 1, s->quarter_sample);

  723.         s->mv[1][0][1] = scale_mv(s->next_picture.motion_val[1][xy][1], v->bfraction, 1, s->quarter_sample);

  724. 

  725.         /* Pullback predicted motion vectors as specified in 8.4.5.4 */

  726.         s->mv[0][0][0] = av_clip(s->mv[0][0][0], -60 - (s->mb_x << 6), (s->mb_width  << 6) - 4 - (s->mb_x << 6));

  727.         s->mv[0][0][1] = av_clip(s->mv[0][0][1], -60 - (s->mb_y << 6), (s->mb_height << 6) - 4 - (s->mb_y << 6));

  728.         s->mv[1][0][0] = av_clip(s->mv[1][0][0], -60 - (s->mb_x << 6), (s->mb_width  << 6) - 4 - (s->mb_x << 6));

  729.         s->mv[1][0][1] = av_clip(s->mv[1][0][1], -60 - (s->mb_y << 6), (s->mb_height << 6) - 4 - (s->mb_y << 6));

  730.     if (direct) {

  731.         s->current_picture.motion_val[0][xy][0] = s->mv[0][0][0];

  732.         s->current_picture.motion_val[0][xy][1] = s->mv[0][0][1];

  733.         s->current_picture.motion_val[1][xy][0] = s->mv[1][0][0];

  734.         s->current_picture.motion_val[1][xy][1] = s->mv[1][0][1];

  735.         return;

  736.     }

  737. 

  738.     if ((mvtype == BMV_TYPE_FORWARD) || (mvtype == BMV_TYPE_INTERPOLATED)) {

  739.         C   = s->current_picture.motion_val[0][xy - 2];

  740.         A   = s->current_picture.motion_val[0][xy - wrap * 2];

  741.         off = (s->mb_x == (s->mb_width - 1)) ? -2 : 2;

  742.         B   = s->current_picture.motion_val[0][xy - wrap * 2 + off];

  743. 

  744.         if (!s->mb_x) C[0] = C[1] = 0;

  745.         if (!s->first_slice_line) { // predictor A is not out of bounds

  746.             if (s->mb_width == 1) {

  747.                 px = A[0];

  748.                 py = A[1];

  749.             } else {

  750.                 px = mid_pred(A[0], B[0], C[0]);

  751.                 py = mid_pred(A[1], B[1], C[1]);

  752.             }

  753.         } else if (s->mb_x) { // predictor C is not out of bounds

  754.             px = C[0];

  755.             py = C[1];

  756.         } else {

  757.             px = py = 0;

  758.         }

  759.         /* Pullback MV as specified in 8.3.5.3.4 */

  760.         {

  761.             int qx, qy, X, Y;

  762.             int sh = v->profile < PROFILE_ADVANCED ? 5 : 6;

  763.             int MV = 4 - (1 << sh);

  764.             qx = (s->mb_x << sh);

  765.             qy = (s->mb_y << sh);

  766.             X  = (s->mb_width  << sh) - 4;

  767.             Y  = (s->mb_height << sh) - 4;

  768.             if (qx + px < MV) px = MV - qx;

  769.             if (qy + py < MV) py = MV - qy;

  770.             if (qx + px > X) px = X - qx;

  771.             if (qy + py > Y) py = Y - qy;

  772.         }

  773.         /* Calculate hybrid prediction as specified in 8.3.5.3.5 */

  774.         if (0 && !s->first_slice_line && s->mb_x) {

  775.             if (is_intra[xy - wrap])

  776.                 sum = FFABS(px) + FFABS(py);

  777.             else

  778.                 sum = FFABS(px - A[0]) + FFABS(py - A[1]);

  779.             if (sum > 32) {

  780.                 if (get_bits1(&s->gb)) {

  781.                     px = A[0];

  782.                     py = A[1];

  783.                 } else {

  784.                     px = C[0];

  785.                     py = C[1];

  786.                 }

  787.             } else {

  788.                 if (is_intra[xy - 2])

  789.                     sum = FFABS(px) + FFABS(py);

  790.                 else

  791.                     sum = FFABS(px - C[0]) + FFABS(py - C[1]);

  792.                 if (sum > 32) {

  793.                     if (get_bits1(&s->gb)) {

  794.                         px = A[0];

  795.                         py = A[1];

  796.                     } else {

  797.                         px = C[0];

  798.                         py = C[1];

  799.                     }

  800.                 }

  801.             }

  802.         }

  803.         /* store MV using signed modulus of MV range defined in 4.11 */

  804.         s->mv[0][0][0] = ((px + dmv_x[0] + r_x) & ((r_x << 1) - 1)) - r_x;

  805.         s->mv[0][0][1] = ((py + dmv_y[0] + r_y) & ((r_y << 1) - 1)) - r_y;

  806.     }

  807.     if ((mvtype == BMV_TYPE_BACKWARD) || (mvtype == BMV_TYPE_INTERPOLATED)) {

  808.         C   = s->current_picture.motion_val[1][xy - 2];

  809.         A   = s->current_picture.motion_val[1][xy - wrap * 2];

  810.         off = (s->mb_x == (s->mb_width - 1)) ? -2 : 2;

  811.         B   = s->current_picture.motion_val[1][xy - wrap * 2 + off];

  812. 

  813.         if (!s->mb_x)

  814.             C[0] = C[1] = 0;

  815.         if (!s->first_slice_line) { // predictor A is not out of bounds

  816.             if (s->mb_width == 1) {

  817.                 px = A[0];

  818.                 py = A[1];

  819.             } else {

  820.                 px = mid_pred(A[0], B[0], C[0]);

  821.                 py = mid_pred(A[1], B[1], C[1]);

  822.             }

  823.         } else if (s->mb_x) { // predictor C is not out of bounds

  824.             px = C[0];

  825.             py = C[1];

  826.         } else {

  827.             px = py = 0;

  828.         }

  829.         /* Pullback MV as specified in 8.3.5.3.4 */

  830.         {

  831.             int qx, qy, X, Y;

  832.             int sh = v->profile < PROFILE_ADVANCED ? 5 : 6;

  833.             int MV = 4 - (1 << sh);

  834.             qx = (s->mb_x << sh);

  835.             qy = (s->mb_y << sh);

  836.             X  = (s->mb_width  << sh) - 4;

  837.             Y  = (s->mb_height << sh) - 4;

  838.             if (qx + px < MV) px = MV - qx;

  839.             if (qy + py < MV) py = MV - qy;

  840.             if (qx + px > X) px = X - qx;

  841.             if (qy + py > Y) py = Y - qy;

  842.         }

  843.         /* Calculate hybrid prediction as specified in 8.3.5.3.5 */

  844.         if (0 && !s->first_slice_line && s->mb_x) {

  845.             if (is_intra[xy - wrap])

  846.                 sum = FFABS(px) + FFABS(py);

  847.             else

  848.                 sum = FFABS(px - A[0]) + FFABS(py - A[1]);

  849.             if (sum > 32) {

  850.                 if (get_bits1(&s->gb)) {

  851.                     px = A[0];

  852.                     py = A[1];

  853.                 } else {

  854.                     px = C[0];

  855.                     py = C[1];

  856.                 }

  857.             } else {

  858.                 if (is_intra[xy - 2])

  859.                     sum = FFABS(px) + FFABS(py);

  860.                 else

  861.                     sum = FFABS(px - C[0]) + FFABS(py - C[1]);

  862.                 if (sum > 32) {

  863.                     if (get_bits1(&s->gb)) {

  864.                         px = A[0];

  865.                         py = A[1];

  866.                     } else {

  867.                         px = C[0];

  868.                         py = C[1];

  869.                     }

  870.                 }

  871.             }

  872.         }

  873.         /* store MV using signed modulus of MV range defined in 4.11 */

  874. 

  875.         s->mv[1][0][0] = ((px + dmv_x[1] + r_x) & ((r_x << 1) - 1)) - r_x;

  876.         s->mv[1][0][1] = ((py + dmv_y[1] + r_y) & ((r_y << 1) - 1)) - r_y;

  877.     }

  878.     s->current_picture.motion_val[0][xy][0] = s->mv[0][0][0];

  879.     s->current_picture.motion_val[0][xy][1] = s->mv[0][0][1];

  880.     s->current_picture.motion_val[1][xy][0] = s->mv[1][0][0];

  881.     s->current_picture.motion_val[1][xy][1] = s->mv[1][0][1];

  882. }

  883. 

  884. void ff_vc1_pred_b_mv_intfi(VC1Context *v, int n, int *dmv_x, int *dmv_y,

  885.                             int mv1, int *pred_flag)

  886. {

  887.     int dir = (v->bmvtype == BMV_TYPE_BACKWARD) ? 1 : 0;

  888.     MpegEncContext *s = &v->s;

  889.     int mb_pos = s->mb_x + s->mb_y * s->mb_stride;

  890. 

  891.     if (v->bmvtype == BMV_TYPE_DIRECT) {

  892.         int total_opp, k, f;

  893.         if (s->next_picture.mb_type[mb_pos + v->mb_off] != MB_TYPE_INTRA) {

  894.             s->mv[0][0][0] = scale_mv(s->next_picture.motion_val[1][s->block_index[0] + v->blocks_off][0],

  895.                                       v->bfraction, 0, s->quarter_sample);

  896.             s->mv[0][0][1] = scale_mv(s->next_picture.motion_val[1][s->block_index[0] + v->blocks_off][1],

  897.                                       v->bfraction, 0, s->quarter_sample);

  898.             s->mv[1][0][0] = scale_mv(s->next_picture.motion_val[1][s->block_index[0] + v->blocks_off][0],

  899.                                       v->bfraction, 1, s->quarter_sample);

  900.             s->mv[1][0][1] = scale_mv(s->next_picture.motion_val[1][s->block_index[0] + v->blocks_off][1],

  901.                                       v->bfraction, 1, s->quarter_sample);

  902. 

  903.             total_opp = v->mv_f_next[0][s->block_index[0] + v->blocks_off]

  904.                       + v->mv_f_next[0][s->block_index[1] + v->blocks_off]

  905.                       + v->mv_f_next[0][s->block_index[2] + v->blocks_off]

  906.                       + v->mv_f_next[0][s->block_index[3] + v->blocks_off];

  907.             f = (total_opp > 2) ? 1 : 0;

  908.         } else {

  909.             s->mv[0][0][0] = s->mv[0][0][1] = 0;

  910.             s->mv[1][0][0] = s->mv[1][0][1] = 0;

  911.             f = 0;

  912.         }

  913.         v->ref_field_type[0] = v->ref_field_type[1] = v->cur_field_type ^ f;

  914.         for (k = 0; k < 4; k++) {

  915.             s->current_picture.motion_val[0][s->block_index[k] + v->blocks_off][0] = s->mv[0][0][0];

  916.             s->current_picture.motion_val[0][s->block_index[k] + v->blocks_off][1] = s->mv[0][0][1];

  917.             s->current_picture.motion_val[1][s->block_index[k] + v->blocks_off][0] = s->mv[1][0][0];

  918.             s->current_picture.motion_val[1][s->block_index[k] + v->blocks_off][1] = s->mv[1][0][1];

  919.             v->mv_f[0][s->block_index[k] + v->blocks_off] = f;

  920.             v->mv_f[1][s->block_index[k] + v->blocks_off] = f;

  921.         }

  922.         return;

  923.     }

  924.     if (v->bmvtype == BMV_TYPE_INTERPOLATED) {

  925.         ff_vc1_pred_mv(v, 0, dmv_x[0], dmv_y[0],   1, v->range_x, v->range_y, v->mb_type[0], pred_flag[0], 0);

  926.         ff_vc1_pred_mv(v, 0, dmv_x[1], dmv_y[1],   1, v->range_x, v->range_y, v->mb_type[0], pred_flag[1], 1);

  927.         return;

  928.     }

  929.     if (dir) { // backward

  930.         ff_vc1_pred_mv(v, n, dmv_x[1], dmv_y[1], mv1, v->range_x, v->range_y, v->mb_type[0], pred_flag[1], 1);

  931.         if (n == 3 || mv1) {

  932.             ff_vc1_pred_mv(v, 0, dmv_x[0], dmv_y[0],   1, v->range_x, v->range_y, v->mb_type[0], 0, 0);

  933.         }

  934.     } else { // forward

  935.         ff_vc1_pred_mv(v, n, dmv_x[0], dmv_y[0], mv1, v->range_x, v->range_y, v->mb_type[0], pred_flag[0], 0);

  936.         if (n == 3 || mv1) {

  937.             ff_vc1_pred_mv(v, 0, dmv_x[1], dmv_y[1],   1, v->range_x, v->range_y, v->mb_type[0], 0, 1);

  938.         }

  939.     }

  940. }