avcodec/snowenc: Fix used reference MV in fullpel iterative ME

This very very slightly improves quality, no measurable speed change
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/snowenc.c

@@ -1112,13 +1112,15 @@ static void iterative_me(SnowContext *s){
                     /* fullpel ME */
                     //FIXME avoid subpel interpolation / round to nearest integer
                     do{
+                        int newx = block->mx;
+                        int newy = block->my;
                         dia_change=0;
                         for(i=0; i<FFMAX(s->avctx->dia_size, 1); i++){
                             for(j=0; j<i; j++){
-                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx+4*(i-j), block->my+(4*j), obmc_edged, &best_rd);
-                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx-4*(i-j), block->my-(4*j), obmc_edged, &best_rd);
-                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx+4*(i-j), block->my-(4*j), obmc_edged, &best_rd);
-                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx-4*(i-j), block->my+(4*j), obmc_edged, &best_rd);
+                                dia_change |= check_block_inter(s, mb_x, mb_y, newx+4*(i-j), newy+(4*j), obmc_edged, &best_rd);
+                                dia_change |= check_block_inter(s, mb_x, mb_y, newx-4*(i-j), newy-(4*j), obmc_edged, &best_rd);
+                                dia_change |= check_block_inter(s, mb_x, mb_y, newx+4*(i-j), newy-(4*j), obmc_edged, &best_rd);
+                                dia_change |= check_block_inter(s, mb_x, mb_y, newx-4*(i-j), newy+(4*j), obmc_edged, &best_rd);
                             }
                         }
                     }while(dia_change);

tests/ref/vsynth/vsynth1-snow

-e4de85f539ef50b08d2a1dc7e57c7f49 *tests/data/fate/vsynth1-snow.avi
-136080 tests/data/fate/vsynth1-snow.avi
-91021b7d6d7908648fe78cc1975af8c4 *tests/data/fate/vsynth1-snow.out.rawvideo
+61915927233f94db766dd968e750d6a8 *tests/data/fate/vsynth1-snow.avi
+136324 tests/data/fate/vsynth1-snow.avi
+443a1fbdfea490453e790b7e99c0c8df *tests/data/fate/vsynth1-snow.out.rawvideo
 stddev:   22.77 PSNR: 20.98 MAXDIFF:  172 bytes:  7603200/  7603200

tests/ref/vsynth/vsynth1-snow-hpel

-a9e99877f757a99816fd82461d047812 *tests/data/fate/vsynth1-snow-hpel.avi
-138704 tests/data/fate/vsynth1-snow-hpel.avi
-d6845c8f1310e041afdcebc6bbfc449b *tests/data/fate/vsynth1-snow-hpel.out.rawvideo
+a49202654daa09408565be55b2a18010 *tests/data/fate/vsynth1-snow-hpel.avi
+138684 tests/data/fate/vsynth1-snow-hpel.avi
+00a7d96a4829e4babbe496bb0d1a1cdc *tests/data/fate/vsynth1-snow-hpel.out.rawvideo
 stddev:   22.74 PSNR: 20.99 MAXDIFF:  171 bytes:  7603200/  7603200