10l: bidir_refine didn't save the new mvs. also improve speed.

Originally committed as revision 4832 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/motion_est.c

@@ -1636,6 +1636,12 @@ static inline int bidir_refine(MpegEncContext * s, int mb_x, int mb_y)
     const int ymin= c->ymin<<shift;
     const int xmax= c->xmax<<shift;
     const int ymax= c->ymax<<shift;
+    uint8_t map[8][8][8][8];
+
+    memset(map,0,sizeof(map));
+#define BIDIR_MAP(fx,fy,bx,by) \
+    map[(motion_fx+fx)&7][(motion_fy+fy)&7][(motion_bx+bx)&7][(motion_by+by)&7]
+    BIDIR_MAP(0,0,0,0) = 1;
 
     fbmin= check_bidir_mv(s, motion_fx, motion_fy,
                           motion_bx, motion_by,
@@ -1646,8 +1652,10 @@ static inline int bidir_refine(MpegEncContext * s, int mb_x, int mb_y)
     if(s->avctx->bidir_refine){
         int score, end;
 #define CHECK_BIDIR(fx,fy,bx,by)\
-    if(  (fx<=0 || motion_fx+fx<=xmax) && (fy<=0 || motion_fy+fy<=ymax) && (bx<=0 || motion_bx+bx<=xmax) && (by<=0 || motion_by+by<=ymax)\
+    if( !BIDIR_MAP(fx,fy,bx,by)\
+       &&(fx<=0 || motion_fx+fx<=xmax) && (fy<=0 || motion_fy+fy<=ymax) && (bx<=0 || motion_bx+bx<=xmax) && (by<=0 || motion_by+by<=ymax)\
        &&(fx>=0 || motion_fx+fx>=xmin) && (fy>=0 || motion_fy+fy>=ymin) && (bx>=0 || motion_bx+bx>=xmin) && (by>=0 || motion_by+by>=ymin)){\
+        BIDIR_MAP(fx,fy,bx,by) = 1;\
         score= check_bidir_mv(s, motion_fx+fx, motion_fy+fy, motion_bx+bx, motion_by+by, pred_fx, pred_fy, pred_bx, pred_by, 0, 16);\
         if(score < fbmin){\
             fbmin= score;\
@@ -1696,6 +1704,11 @@ CHECK_BIDIR2(d,a,b,c)
         }while(!end);
     }
 
+    s->b_bidir_forw_mv_table[xy][0]= motion_fx;
+    s->b_bidir_forw_mv_table[xy][1]= motion_fy;
+    s->b_bidir_back_mv_table[xy][0]= motion_bx;
+    s->b_bidir_back_mv_table[xy][1]= motion_by;
+
     return fbmin;
 }