vp9-denoiser: Adjust usage of skin and consec_zeromv.

Change-Id: I250258fc70ec0fcf1b501708c5d4b84685cf882e

vp9/encoder/vp9_denoiser.c

@@ -195,7 +195,8 @@ static VP9_DENOISER_DECISION perform_motion_compensation(VP9_DENOISER *denoiser,
                                                          PICK_MODE_CONTEXT *ctx,
                                                          int motion_magnitude,
                                                          int is_skin,
-                                                         int *zeromv_filter) {
+                                                         int *zeromv_filter,
+                                                         int consec_zeromv) {
   int mv_col, mv_row;
   int sse_diff = ctx->zeromv_sse - ctx->newmv_sse;
   MV_REFERENCE_FRAME frame;
@@ -212,7 +213,7 @@ static VP9_DENOISER_DECISION perform_motion_compensation(VP9_DENOISER *denoiser,
 
   saved_mi = *mi;
 
-  if (is_skin && motion_magnitude > 0)
+  if (is_skin && (motion_magnitude > 0 || consec_zeromv < 4))
     return COPY_BLOCK;
 
   // If the best reference frame uses inter-prediction and there is enough of a
@@ -332,6 +333,7 @@ void vp9_denoiser_denoise(VP9_COMP *cpi, MACROBLOCK *mb,
                                           mi_row, mi_col);
   struct buf_2d src = mb->plane[0].src;
   int is_skin = 0;
+  int consec_zeromv = 0;
   mv_col = ctx->best_sse_mv.as_mv.col;
   mv_row = ctx->best_sse_mv.as_mv.row;
   motion_magnitude = mv_row * mv_row + mv_col * mv_col;
@@ -343,7 +345,7 @@ void vp9_denoiser_denoise(VP9_COMP *cpi, MACROBLOCK *mb,
     // If motion for current block is small/zero, compute consec_zeromv for
     // skin detection (early exit in skin detection is done for large
     // consec_zeromv when current block has small/zero motion).
-    int consec_zeromv = 0;
+    consec_zeromv = 0;
     if (motion_level == 0) {
       CYCLIC_REFRESH *const cr = cpi->cyclic_refresh;
       VP9_COMMON * const cm = &cpi->common;
@@ -361,8 +363,8 @@ void vp9_denoiser_denoise(VP9_COMP *cpi, MACROBLOCK *mb,
           consec_zeromv = VPXMIN(cr->consec_zero_mv[bl_index], consec_zeromv);
           // No need to keep checking 8x8 blocks if any of the sub-blocks
           // has small consec_zeromv (since threshold for no_skin based on
-          // zero/small motion in skin detection is high, i.e, > 5).
-          if (consec_zeromv < 5) {
+          // zero/small motion in skin detection is high, i.e, > 4).
+          if (consec_zeromv < 4) {
             i = ymis;
             j = xmis;
           }
@@ -393,7 +395,8 @@ void vp9_denoiser_denoise(VP9_COMP *cpi, MACROBLOCK *mb,
                                            mi_row, mi_col, ctx,
                                            motion_magnitude,
                                            is_skin,
-                                           &zeromv_filter);
+                                           &zeromv_filter,
+                                           consec_zeromv);
 
   if (decision == FILTER_BLOCK) {
     decision = vp9_denoiser_filter(src.buf, src.stride,