Add normalization over frame level Wiener variance

Normalize the block level Wiener variance based decision according
to the frame level Wiener variance.

Change-Id: Ic2bdf1b322a65661775541dd6c174ba71579461a

diff --git a/vp9/encoder/vp9_encoder.c b/vp9/encoder/vp9_encoder.c
index 08d9e29..868ec3a 100644 (file)
--- a/vp9/encoder/vp9_encoder.c
+++ b/vp9/encoder/vp9_encoder.c
@@ -4732,7 +4732,7 @@ static void set_mb_wiener_variance(VP9_COMP *cpi) {
   DECLARE_ALIGNED(16, int16_t, src_diff[32 * 32]);
   DECLARE_ALIGNED(16, tran_low_t, coeff[32 * 32]);
 
-  int mb_row, mb_col;
+  int mb_row, mb_col, count = 0;
   // Hard coded operating block size
   const int block_size = 16;
   const int coeff_count = block_size * block_size;
@@ -4749,6 +4749,8 @@ static void set_mb_wiener_variance(VP9_COMP *cpi) {
 
   memset(zero_pred, 0, sizeof(*zero_pred) * coeff_count);
 
+  cpi->norm_wiener_variance = 0;
+
   for (mb_row = 0; mb_row < cm->mb_rows; ++mb_row) {
     for (mb_col = 0; mb_col < cm->mb_cols; ++mb_col) {
       int idx, hist_count = 0;
@@ -4789,18 +4791,21 @@ static void set_mb_wiener_variance(VP9_COMP *cpi) {
 
       // Wiener filter
       for (idx = 1; idx < coeff_count; ++idx) {
-        int sign = coeff[idx] < 0;
         int64_t sqr_coeff = (int64_t)coeff[idx] * coeff[idx];
         coeff[idx] = (int16_t)((sqr_coeff * coeff[idx]) /
                                (sqr_coeff + (int64_t)median_val * median_val));
-        if (sign) coeff[idx] = -coeff[idx];
-
         wiener_variance += (int64_t)coeff[idx] * coeff[idx];
       }
       cpi->mb_wiener_variance[mb_row * cm->mb_cols + mb_col] =
           wiener_variance / coeff_count;
+      cpi->norm_wiener_variance +=
+          cpi->mb_wiener_variance[mb_row * cm->mb_cols + mb_col];
+      ++count;
     }
   }
+
+  if (count) cpi->norm_wiener_variance /= count;
+  cpi->norm_wiener_variance = VPXMAX(1, cpi->norm_wiener_variance);
 }
 
 static void encode_frame_to_data_rate(VP9_COMP *cpi, size_t *size,

diff --git a/vp9/encoder/vp9_encoder.h b/vp9/encoder/vp9_encoder.h
index 8472905..e578646 100644 (file)
--- a/vp9/encoder/vp9_encoder.h
+++ b/vp9/encoder/vp9_encoder.h
@@ -628,6 +628,7 @@ typedef struct VP9_COMP {
   int ext_refresh_frame_context_pending;
   int ext_refresh_frame_context;
 
+  int64_t norm_wiener_variance;
   int64_t *mb_wiener_variance;
   int *stack_rank_buffer;