commit cdcac6d5bfcfdaae2e132949a4ed67bf8c588610
author David Barker <david.barker@argondesign.com> Thu Dec 01 17:04:16 2016 +0000
committer Debargha Mukherjee <debargha@google.com> Thu Dec 01 20:11:31 2016 +0000
tree 01e0f66b281e127bb6b69612b918e3e1f0c8c691
parent deaf05ea3fe84a320b557d95139d5b3553a07582

Make gm_get_motion_vector respect allow_high_precision_mv

This fixes a rare encode/decode mismatch due to inconsistent
rounding of NEARMV/NEARESTMV vs. ZEROMV motion vectors when both
global motion and ref-mv are enabled.

Change-Id: Ia2bbaf63020f5ce7762e027f9bf835fd96797bec

av1/decoder/decodemv.c

diff --git a/av1/decoder/decodemv.c b/av1/decoder/decodemv.c
index 05dc0fa..838c9af 100644
--- a/av1/decoder/decodemv.c
+++ b/av1/decoder/decodemv.c
@@ -1230,11 +1230,13 @@
     }
     case ZEROMV: {
 #if CONFIG_GLOBAL_MOTION
-      mv[0].as_int =
-          gm_get_motion_vector(&cm->global_motion[ref_frame[0]]).as_int;
+      mv[0].as_int = gm_get_motion_vector(&cm->global_motion[ref_frame[0]],
+                                          cm->allow_high_precision_mv)
+                         .as_int;
       if (is_compound)
-        mv[1].as_int =
-            gm_get_motion_vector(&cm->global_motion[ref_frame[1]]).as_int;
+        mv[1].as_int = gm_get_motion_vector(&cm->global_motion[ref_frame[1]],
+                                            cm->allow_high_precision_mv)
+                           .as_int;
 #else
       mv[0].as_int = 0;
       if (is_compound) mv[1].as_int = 0;
@@ -1479,14 +1481,29 @@
 
     if (xd->ref_mv_count[ref_frame] < 2) {
       MV_REFERENCE_FRAME rf[2];
+      int_mv zeromv[2];
       av1_set_ref_frame(rf, ref_frame);
+#if CONFIG_GLOBAL_MOTION
+      zeromv[0].as_int = gm_get_motion_vector(&cm->global_motion[rf[0]],
+                                              cm->allow_high_precision_mv)
+                             .as_int;
+      zeromv[1].as_int = (rf[1] != NONE)
+                             ? gm_get_motion_vector(&cm->global_motion[rf[1]],
+                                                    cm->allow_high_precision_mv)
+                                   .as_int
+                             : 0;
+#else
+      zeromv[0].as_int = zeromv[1].as_int = 0;
+#endif
       for (ref = 0; ref < 2; ++ref) {
         lower_mv_precision(&ref_mvs[rf[ref]][0].as_mv, allow_hp);
         lower_mv_precision(&ref_mvs[rf[ref]][1].as_mv, allow_hp);
       }
 
-      if (ref_mvs[rf[0]][0].as_int != 0 || ref_mvs[rf[0]][1].as_int != 0 ||
-          ref_mvs[rf[1]][0].as_int != 0 || ref_mvs[rf[1]][1].as_int != 0)
+      if (ref_mvs[rf[0]][0].as_int != zeromv[0].as_int ||
+          ref_mvs[rf[0]][1].as_int != zeromv[0].as_int ||
+          ref_mvs[rf[1]][0].as_int != zeromv[1].as_int ||
+          ref_mvs[rf[1]][1].as_int != zeromv[1].as_int)
         inter_mode_ctx[ref_frame] &= ~(1 << ALL_ZERO_FLAG_OFFSET);
     }
   }