a new way of determining reference motion vector

Using surrounding reconstructed pixels from left and above to select
best matching mv to use as reference motion vector for mv encoding.

Test results:
       AVGPSNR  GLBPSNR VPXSSIM
Derf:  1.107%   1.062%  0.992%
Std-hd:1.209%   1.176%  1.029%

Change-Id: I8f10e09ee6538c05df2fb9f069abcaf1edb3fca6

1 files changed, 26 insertions, 21 deletions

diff --git a/vp8/common/findnearmv.h b/vp8/common/findnearmv.h
index d4769e608..3bb2024c2 100644
--- a/vp8/common/findnearmv.h
+++ b/vp8/common/findnearmv.h
@@ -33,20 +33,14 @@ static void mv_bias(int refmb_ref_frame_sign_bias, int refframe, int_mv *mvp, co
 
 #define LEFT_TOP_MARGIN (16 << 3)
 #define RIGHT_BOTTOM_MARGIN (16 << 3)
-static void vp8_clamp_mv2(int_mv *mv, const MACROBLOCKD *xd) {
-  if (mv->as_mv.col < (xd->mb_to_left_edge - LEFT_TOP_MARGIN))
-    mv->as_mv.col = xd->mb_to_left_edge - LEFT_TOP_MARGIN;
-  else if (mv->as_mv.col > xd->mb_to_right_edge + RIGHT_BOTTOM_MARGIN)
-    mv->as_mv.col = xd->mb_to_right_edge + RIGHT_BOTTOM_MARGIN;
-
-  if (mv->as_mv.row < (xd->mb_to_top_edge - LEFT_TOP_MARGIN))
-    mv->as_mv.row = xd->mb_to_top_edge - LEFT_TOP_MARGIN;
-  else if (mv->as_mv.row > xd->mb_to_bottom_edge + RIGHT_BOTTOM_MARGIN)
-    mv->as_mv.row = xd->mb_to_bottom_edge + RIGHT_BOTTOM_MARGIN;
-}
 
-static void vp8_clamp_mv(int_mv *mv, int mb_to_left_edge, int mb_to_right_edge,
-                         int mb_to_top_edge, int mb_to_bottom_edge) {
+
+
+static void vp8_clamp_mv(int_mv *mv,
+                         int mb_to_left_edge,
+                         int mb_to_right_edge,
+                         int mb_to_top_edge,
+                         int mb_to_bottom_edge) {
   mv->as_mv.col = (mv->as_mv.col < mb_to_left_edge) ?
                   mb_to_left_edge : mv->as_mv.col;
   mv->as_mv.col = (mv->as_mv.col > mb_to_right_edge) ?
@@ -56,15 +50,26 @@ static void vp8_clamp_mv(int_mv *mv, int mb_to_left_edge, int mb_to_right_edge,
   mv->as_mv.row = (mv->as_mv.row > mb_to_bottom_edge) ?
                   mb_to_bottom_edge : mv->as_mv.row;
 }
-static unsigned int vp8_check_mv_bounds(int_mv *mv, int mb_to_left_edge,
-                                        int mb_to_right_edge, int mb_to_top_edge,
+
+static void vp8_clamp_mv2(int_mv *mv, const MACROBLOCKD *xd) {
+  vp8_clamp_mv(mv,
+              xd->mb_to_left_edge - LEFT_TOP_MARGIN,
+              xd->mb_to_right_edge + RIGHT_BOTTOM_MARGIN,
+              xd->mb_to_top_edge - LEFT_TOP_MARGIN,
+              xd->mb_to_bottom_edge + RIGHT_BOTTOM_MARGIN);
+}
+
+
+
+static unsigned int vp8_check_mv_bounds(int_mv *mv,
+                                        int mb_to_left_edge,
+                                        int mb_to_right_edge,
+                                        int mb_to_top_edge,
                                         int mb_to_bottom_edge) {
-  unsigned int need_to_clamp;
-  need_to_clamp = (mv->as_mv.col < mb_to_left_edge) ? 1 : 0;
-  need_to_clamp |= (mv->as_mv.col > mb_to_right_edge) ? 1 : 0;
-  need_to_clamp |= (mv->as_mv.row < mb_to_top_edge) ? 1 : 0;
-  need_to_clamp |= (mv->as_mv.row > mb_to_bottom_edge) ? 1 : 0;
-  return need_to_clamp;
+  return (mv->as_mv.col < mb_to_left_edge) ||
+         (mv->as_mv.col > mb_to_right_edge) ||
+         (mv->as_mv.row < mb_to_top_edge) ||
+         (mv->as_mv.row > mb_to_bottom_edge);
 }
 
 void vp8_find_near_mvs