BITSTREAM - CLARIFICATION OF MV SIZE RANGE

The codec should effectively run with motion vector of range (-2048, 2047)
in full pixels, for sequences of 1080p and below. Add assertions to clarify
this behavior.

Change-Id: Ia0cac28249f587d8f8882205228fa480263ab313

1 files changed, 13 insertions, 1 deletions

diff --git a/vp9/decoder/vp9_decodemv.c b/vp9/decoder/vp9_decodemv.c
index c697d665d..18e6ea0ef 100644
--- a/vp9/decoder/vp9_decodemv.c
+++ b/vp9/decoder/vp9_decodemv.c
@@ -522,8 +522,14 @@ static void read_inter_block_mode_info(VP9D_COMP *pbi, MODE_INFO *mi,
             assert(!"Invalid inter mode value");
         }
         mi->bmi[j].as_mv[0].as_int = block[0].as_int;
-        if (is_compound)
+        assert(block[0].as_mv.row < MV_UPP && block[0].as_mv.row > MV_LOW);
+        assert(block[0].as_mv.col < MV_UPP && block[0].as_mv.col > MV_LOW);
+
+        if (is_compound) {
           mi->bmi[j].as_mv[1].as_int = block[1].as_int;
+          assert(block[1].as_mv.row < MV_UPP && block[1].as_mv.row > MV_LOW);
+          assert(block[1].as_mv.col < MV_UPP && block[1].as_mv.col > MV_LOW);
+        }
 
         if (num_4x4_h == 2)
           mi->bmi[j + 2] = mi->bmi[j];
@@ -564,6 +570,12 @@ static void read_inter_block_mode_info(VP9D_COMP *pbi, MODE_INFO *mi,
       default:
         assert(!"Invalid inter mode value");
     }
+    assert(mv0->as_mv.row < MV_UPP && mv0->as_mv.row > MV_LOW);
+    assert(mv0->as_mv.col < MV_UPP && mv0->as_mv.col > MV_LOW);
+    if (is_compound) {
+      assert(mv1->as_mv.row < MV_UPP && mv1->as_mv.row > MV_LOW);
+      assert(mv1->as_mv.col < MV_UPP && mv1->as_mv.col > MV_LOW);
+    }
   }
 }