Detect spatial direct MBs partitioned smaller than 16x16 that can be partitioned

as 16x16 (except ones changing interlacing relative to the colocated MB).
20 cycles slower during MV generation
175 cycles faster during MC


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@21690 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavcodec/h264_direct.c

@@ -319,6 +319,7 @@ single_col:
             fill_rectangle(&h->mv_cache[0][scan8[0]], 4, 4, 8, a, 4);
             fill_rectangle(&h->mv_cache[1][scan8[0]], 4, 4, 8, b, 4);
         }else{
+            int n=0;
             for(i8=0; i8<4; i8++){
                 const int x8 = i8&1;
                 const int y8 = i8>>1;
@@ -344,6 +345,7 @@ single_col:
                                 fill_rectangle(&h->mv_cache[0][scan8[i8*4]], 2, 2, 8, 0, 4);
                             if(ref[1] == 0)
                                 fill_rectangle(&h->mv_cache[1][scan8[i8*4]], 2, 2, 8, 0, 4);
+                            n+=4;
                         }
                     }else{
                         int m=0;
@@ -359,9 +361,12 @@ single_col:
                     }
                     if(!(m&3))
                         h->sub_mb_type[i8]+= MB_TYPE_16x16 - MB_TYPE_8x8;
+                    n+=m;
                     }
                 }
             }
+            if(!is_b8x8 && !(n&15))
+                *mb_type= (*mb_type & ~(MB_TYPE_8x8|MB_TYPE_16x8|MB_TYPE_8x16|MB_TYPE_P1L0|MB_TYPE_P1L1))|MB_TYPE_16x16|MB_TYPE_DIRECT2;
         }
     }else{ /* direct temporal mv pred */
         const int *map_col_to_list0[2] = {h->map_col_to_list0[0], h->map_col_to_list0[1]};