Removed MV costing from ARNR filtering

The ARNR filter uses a motion compensated temporal filter,
but the motion estimation implementation accounts for the
cost of the mv in its decision making process. The ARNR
filter uses a dummy cost table initialized to 0 as a way
to ignore the mv costs (which are irrelevant to the filter).

This CL modifies the ARNR filter implementation so that
the mv costing is ignored without the requirement for
dummy tables.

Change-Id: I4196aa5c24da63f858ff54fbaa5fc85ae1f1957f

2 files changed, 30 insertions, 27 deletions

diff --git a/vp8/encoder/mcomp.c b/vp8/encoder/mcomp.c
index 67e4f7ead..dc0edfbc1 100644
--- a/vp8/encoder/mcomp.c
+++ b/vp8/encoder/mcomp.c
@@ -34,17 +34,23 @@ int vp8_mv_bit_cost(int_mv *mv, int_mv *ref, int *mvcost[2], int Weight)
 
 static int mv_err_cost(int_mv *mv, int_mv *ref, int *mvcost[2], int error_per_bit)
 {
-    return ((mvcost[0][(mv->as_mv.row - ref->as_mv.row) >> 1] +
-        mvcost[1][(mv->as_mv.col - ref->as_mv.col) >> 1])
-        * error_per_bit + 128) >> 8;
+    // Ignore mv costing if mvcost is NULL
+    if (mvcost)
+        return ((mvcost[0][(mv->as_mv.row - ref->as_mv.row) >> 1] +
+                 mvcost[1][(mv->as_mv.col - ref->as_mv.col) >> 1])
+                 * error_per_bit + 128) >> 8;
+    return 0;
 }
 
 static int mvsad_err_cost(int_mv *mv, int_mv *ref, int *mvsadcost[2], int error_per_bit)
 {
-    /* Calculate sad error cost on full pixel basis. */
-    return ((mvsadcost[0][(mv->as_mv.row - ref->as_mv.row)] +
-        mvsadcost[1][(mv->as_mv.col - ref->as_mv.col)])
-        * error_per_bit + 128) >> 8;
+    // Calculate sad error cost on full pixel basis.
+    // Ignore mv costing if mvsadcost is NULL
+    if (mvsadcost)
+        return ((mvsadcost[0][(mv->as_mv.row - ref->as_mv.row)] +
+                 mvsadcost[1][(mv->as_mv.col - ref->as_mv.col)])
+                * error_per_bit + 128) >> 8;
+    return 0;
 }
 
 void vp8_init_dsmotion_compensation(MACROBLOCK *x, int stride)
@@ -176,7 +182,7 @@ void vp8_init3smotion_compensation(MACROBLOCK *x, int stride)
  * 32 cols area that is enough for 16x16 macroblock. Later, for SPLITMV, we
  * could reduce the area.
  */
-#define MVC(r,c) (((mvcost[0][(r)-rr] + mvcost[1][(c) - rc]) * error_per_bit + 128 )>>8 ) // estimated cost of a motion vector (r,c)
+#define MVC(r,c) (mvcost ? ((mvcost[0][(r)-rr] + mvcost[1][(c) - rc]) * error_per_bit + 128 )>>8 : 0) // estimated cost of a motion vector (r,c)
 #define PRE(r,c) (y + (((r)>>2) * y_stride + ((c)>>2) -(offset))) // pointer to predictor base of a motionvector
 #define SP(x) (((x)&3)<<1) // convert motion vector component to offset for svf calc
 #define DIST(r,c) vfp->svf( PRE(r,c), y_stride, SP(c),SP(r), z,b->src_stride,&sse) // returns subpixel variance error function.
diff --git a/vp8/encoder/temporal_filter.c b/vp8/encoder/temporal_filter.c
index 20bdf1789..b82ea47cb 100644
--- a/vp8/encoder/temporal_filter.c
+++ b/vp8/encoder/temporal_filter.c
@@ -134,7 +134,6 @@ void vp8_temporal_filter_apply_c
 }
 
 #if ALT_REF_MC_ENABLED
-static int dummy_cost[2*mv_max+1];
 
 static int vp8_temporal_filter_find_matching_mb_c
 (
@@ -156,9 +155,6 @@ static int vp8_temporal_filter_find_matching_mb_c
     int_mv best_ref_mv1;
     int_mv best_ref_mv1_full; /* full-pixel value of best_ref_mv1 */
 
-    int *mvcost[2]    = { &dummy_cost[mv_max+1], &dummy_cost[mv_max+1] };
-    int *mvsadcost[2] = { &dummy_cost[mv_max+1], &dummy_cost[mv_max+1] };
-
     // Save input state
     unsigned char **base_src = b->base_src;
     int src = b->src;
@@ -196,12 +192,11 @@ static int vp8_temporal_filter_find_matching_mb_c
 
     /*cpi->sf.search_method == HEX*/
     // TODO Check that the 16x16 vf & sdf are selected here
-    bestsme = vp8_hex_search(x, b, d,
-        &best_ref_mv1_full, &d->bmi.mv,
-        step_param,
-        sadpb,
-        &cpi->fn_ptr[BLOCK_16X16],
-        mvsadcost, mvcost, &best_ref_mv1);
+    // Ignore mv costing by sending NULL cost arrays
+    bestsme = vp8_hex_search(x, b, d, &best_ref_mv1_full, &d->bmi.mv,
+                             step_param, sadpb,
+                             &cpi->fn_ptr[BLOCK_16X16],
+                             NULL, NULL, &best_ref_mv1);
 
 #if ALT_REF_SUBPEL_ENABLED
     // Try sub-pixel MC?
@@ -209,10 +204,13 @@ static int vp8_temporal_filter_find_matching_mb_c
     {
         int distortion;
         unsigned int sse;
+        // Ignore mv costing by sending NULL cost array
         bestsme = cpi->find_fractional_mv_step(x, b, d,
-                    &d->bmi.mv, &best_ref_mv1,
-                    x->errorperbit, &cpi->fn_ptr[BLOCK_16X16],
-                    mvcost, &distortion, &sse);
+                                               &d->bmi.mv,
+                                               &best_ref_mv1,
+                                               x->errorperbit,
+                                               &cpi->fn_ptr[BLOCK_16X16],
+                                               NULL, &distortion, &sse);
     }
 #endif
 
@@ -304,12 +302,11 @@ static void vp8_temporal_filter_iterate_c
 
                 // Find best match in this frame by MC
                 err = vp8_temporal_filter_find_matching_mb_c
-                      (cpi,
-                       cpi->frames[alt_ref_index],
-                       cpi->frames[frame],
-                       mb_y_offset,
-                       THRESH_LOW);
-
+                          (cpi,
+                           cpi->frames[alt_ref_index],
+                           cpi->frames[frame],
+                           mb_y_offset,
+                           THRESH_LOW);
 #endif
                 // Assign higher weight to matching MB if it's error
                 // score is lower. If not applying MC default behavior