commit 74978fcb47e668d3f853d68839f7fca5147d3750
author Jingning Han <jingning@google.com> Thu Jul 27 15:27:55 2017 -0700
committer Jingning Han <jingning@google.com> Mon Aug 07 22:35:04 2017 +0000
tree b6f798b7f45b15b7d95da7b4ca4a300a92dacb9d
parent d37b83d81002c3d0c077194d4841a64b78beaf1e

Use the bottom right 4x4 block for 8x8 unit mv reference

When accessing an 8x8 block for motion vector referencing, always
use the bottom right 4x4 block's motion information.

Change-Id: I95e7235f9645ea3dea83482041b9fbd4e764b13f

av1/common/mvref_common.c

diff --git a/av1/common/mvref_common.c b/av1/common/mvref_common.c
index 698a367..f85b97d 100644
--- a/av1/common/mvref_common.c
+++ b/av1/common/mvref_common.c
@@ -166,11 +166,16 @@
                             ? mi_size_wide[BLOCK_4X4]
                             : mi_size_wide[BLOCK_8X8];
   // TODO(jingning): Revisit this part after cb4x4 is stable.
-  if (abs(row_offset) > 1) row_offset *= 2;
+  if (abs(row_offset) > 1) {
+    row_offset *= 2;
+    row_offset += 1;
 
-  if (bsize < BLOCK_8X8 && abs(row_offset) > 1) {
-    if (mi_row & 0x01) row_offset += 1;
-    if (mi_col & 0x01) col_offset -= 1;
+    col_offset = 1;
+
+    if (bsize < BLOCK_8X8) {
+      if (mi_row & 0x01) row_offset += 1;
+      if (mi_col & 0x01) col_offset -= 1;
+    }
   }
 #else
   const int mi_offset = mi_size_wide[BLOCK_8X8];
@@ -220,11 +225,16 @@
   const int mi_offset = (bsize < BLOCK_8X8) || (abs(col_offset) > 1)
                             ? mi_size_high[BLOCK_4X4]
                             : mi_size_high[BLOCK_8X8];
-  if (abs(col_offset) > 1) col_offset *= 2;
+  if (abs(col_offset) > 1) {
+    col_offset *= 2;
+    col_offset += 1;
 
-  if (bsize < BLOCK_8X8 && abs(col_offset) > 1) {
-    if (mi_row & 0x01) row_offset -= 1;
-    if (mi_col & 0x01) col_offset += 1;
+    row_offset = 1;
+
+    if (bsize < BLOCK_8X8) {
+      if (mi_row & 0x01) row_offset -= 1;
+      if (mi_col & 0x01) col_offset += 1;
+    }
   }
 #else
   const int mi_offset = mi_size_wide[BLOCK_8X8];