commit a1ec3eb3263dfc265961cc6d5c13dd7be788798e
author Yaowu Xu <yaowu@google.com> Mon Aug 24 19:09:03 2015 -0700
committer Yaowu Xu <yaowu@google.com> Tue Aug 25 10:00:34 2015 -0700
tree eaf62de71d32077e2feeb27135cfbf0d7e965dd8
parent d88ca3c3354aa58e487683cd8736322a4e814d1c

Limit new motion vector size

This commit adds clamp of new vectors similar to the logic in RD loop.
Such clamp is not necessary from the perspective of VP8 bitstream, but
is added to improve ChromeCast mirroring's robustness.

Change-Id: I42f6adbc60ffce283b994869364230858632d6fa

vp8/encoder/pickinter.c

diff --git a/vp8/encoder/pickinter.c b/vp8/encoder/pickinter.c
index f3443db..5ce98ad 100644
--- a/vp8/encoder/pickinter.c
+++ b/vp8/encoder/pickinter.c
@@ -1240,7 +1240,10 @@
             }
 
             mode_mv[NEWMV].as_int = d->bmi.mv.as_int;
-
+            // The clamp below is not necessary from the perspective
+            // of VP8 bitstream, but is added to improve ChromeCast
+            // mirroring's robustness. Please do not remove.
+            vp8_clamp_mv2(&mode_mv[this_mode], xd);
             /* mv cost; */
             rate2 += vp8_mv_bit_cost(&mode_mv[NEWMV], &best_ref_mv,
                                      cpi->mb.mvcost, 128);
@@ -1248,7 +1251,6 @@
 
         case NEARESTMV:
         case NEARMV:
-
             if (mode_mv[this_mode].as_int == 0)
                 continue;