commit 8da6d9d75cf7f16d05c760900ab8d4aee2520220
author David Barker <david.barker@argondesign.com> Mon Nov 28 11:13:52 2016 +0000
committer Debargha Mukherjee <debargha@google.com> Mon Nov 28 22:43:38 2016 +0000
tree f4f8fd219dc9eaa4b177bb48ae6fe786ce64c8a7
parent 9e218747c4202bb903423e9dae91b853180e52af

Fix a bug with global-motion + ref-mv

av1_find_mv_refs sets the ALL_ZERO flag when either (a) we don't have
enough candidate MVs, or (b) all candidate MVs are zero. With global
motion enabled, case (b) does not work as intended and causes two
problems: a significant quality decrease for foreman_cif.y4m, and
test failures in *CpuSpeedTest*Screencast*.

This patch skips check (b) when global motion is enabled, fixing
the above bugs.

Change-Id: I7461588cb02733563c1439f430b89190299a1b5d

av1/common/mvref_common.c

diff --git a/av1/common/mvref_common.c b/av1/common/mvref_common.c
index ebe6260..31568de 100644
--- a/av1/common/mvref_common.c
+++ b/av1/common/mvref_common.c
@@ -743,7 +743,10 @@
                       find_mv_refs_sync sync, void *const data,
                       int16_t *mode_context) {
 #if CONFIG_REF_MV
-  int idx, all_zero = 1;
+#if !CONFIG_GLOBAL_MOTION
+  int idx;
+#endif
+  int all_zero = 1;
 #endif
 #if CONFIG_EXT_INTER
   av1_update_mv_context(xd, mi, ref_frame, mv_ref_list, -1, mi_row, mi_col,
@@ -766,6 +769,9 @@
   setup_ref_mv_list(cm, xd, ref_frame, ref_mv_count, ref_mv_stack, mv_ref_list,
                     -1, mi_row, mi_col, mode_context);
 
+#if CONFIG_GLOBAL_MOTION
+  if ((*ref_mv_count >= 2) || (ref_frame <= ALTREF_FRAME)) all_zero = 0;
+#else
   if (*ref_mv_count >= 2) {
     for (idx = 0; idx < AOMMIN(3, *ref_mv_count); ++idx) {
       if (ref_mv_stack[idx].this_mv.as_int != 0) all_zero = 0;
@@ -776,6 +782,7 @@
     for (idx = 0; idx < MAX_MV_REF_CANDIDATES; ++idx)
       if (mv_ref_list[idx].as_int != 0) all_zero = 0;
   }
+#endif
 
   if (all_zero) mode_context[ref_frame] |= (1 << ALL_ZERO_FLAG_OFFSET);
 #endif

av1/encoder/rdopt.c

diff --git a/av1/encoder/rdopt.c b/av1/encoder/rdopt.c
index b765d8c..5132271 100644
--- a/av1/encoder/rdopt.c
+++ b/av1/encoder/rdopt.c
@@ -9899,10 +9899,6 @@
           ) {
     int8_t ref_frame_type = av1_ref_frame_type(best_mbmode.ref_frame);
     int16_t mode_ctx = mbmi_ext->mode_context[ref_frame_type];
-#if !CONFIG_EXT_INTER
-    if (best_mbmode.ref_frame[1] > NONE)
-      mode_ctx &= (mbmi_ext->mode_context[best_mbmode.ref_frame[1]] | 0x00ff);
-#endif  // !CONFIG_EXT_INTER
 
     if (mode_ctx & (1 << ALL_ZERO_FLAG_OFFSET)) {
       best_mbmode.mode = ZEROMV;