Save a few bits in slice headers

Don't override the maximum ref index in the slice header if it's the same as the default.
Also update the naming of the relevant variables in the PPS.

diff --git a/common/set.h b/common/set.h
index f55e6e347fb8232af5ec9d6ec1c9a8e1042edad6..978311873ac649486afdcedc72c71e83b8a34689 100644 (file)
--- a/common/set.h
+++ b/common/set.h
@@ -163,8 +163,8 @@ typedef struct
     int b_pic_order;
     int i_num_slice_groups;
 
-    int i_num_ref_idx_l0_active;
-    int i_num_ref_idx_l1_active;
+    int i_num_ref_idx_l0_default_active;
+    int i_num_ref_idx_l1_default_active;
 
     int b_weighted_pred;
     int b_weighted_bipred;

diff --git a/encoder/encoder.c b/encoder/encoder.c
index 2f192915c2d166bd7ff5515fe1ed2d0424cd754e..61a0c75d10180769767b60585ab0228a07bf1418 100644 (file)
--- a/encoder/encoder.c
+++ b/encoder/encoder.c
@@ -1732,10 +1732,13 @@ static inline void x264_slice_init( x264_t *h, int i_nal_type, int i_global_qp )
     {
         x264_slice_header_init( h, &h->sh, h->sps, h->pps, -1, h->i_frame_num, i_global_qp );
 
-        /* always set the real higher num of ref frame used */
-        h->sh.b_num_ref_idx_override = 1;
         h->sh.i_num_ref_idx_l0_active = h->i_ref0 <= 0 ? 1 : h->i_ref0;
         h->sh.i_num_ref_idx_l1_active = h->i_ref1 <= 0 ? 1 : h->i_ref1;
+        if( h->sh.i_num_ref_idx_l0_active != h->pps->i_num_ref_idx_l0_default_active ||
+            (h->sh.i_type == SLICE_TYPE_B && h->sh.i_num_ref_idx_l1_active != h->pps->i_num_ref_idx_l1_default_active) )
+        {
+            h->sh.b_num_ref_idx_override = 1;
+        }
     }
 
     h->fdec->i_frame_num = h->sh.i_frame_num;

diff --git a/encoder/set.c b/encoder/set.c
index 974fb53de72177d1cca60be820440b2718e9ec04..41d5ae25374a6e4ebf157543b8a80823e6297b3c 100644 (file)
--- a/encoder/set.c
+++ b/encoder/set.c
@@ -426,8 +426,8 @@ void x264_pps_init( x264_pps_t *pps, int i_id, x264_param_t *param, x264_sps_t *
     pps->b_pic_order = param->b_interlaced;
     pps->i_num_slice_groups = 1;
 
-    pps->i_num_ref_idx_l0_active = 1;
-    pps->i_num_ref_idx_l1_active = 1;
+    pps->i_num_ref_idx_l0_default_active = param->i_frame_reference;
+    pps->i_num_ref_idx_l1_default_active = 1;
 
     pps->b_weighted_pred = param->analyse.i_weighted_pred > 0;
     pps->b_weighted_bipred = param->analyse.b_weighted_bipred ? 2 : 0;
@@ -485,8 +485,8 @@ void x264_pps_write( bs_t *s, x264_pps_t *pps )
     bs_write( s, 1, pps->b_pic_order );
     bs_write_ue( s, pps->i_num_slice_groups - 1 );
 
-    bs_write_ue( s, pps->i_num_ref_idx_l0_active - 1 );
-    bs_write_ue( s, pps->i_num_ref_idx_l1_active - 1 );
+    bs_write_ue( s, pps->i_num_ref_idx_l0_default_active - 1 );
+    bs_write_ue( s, pps->i_num_ref_idx_l1_default_active - 1 );
     bs_write( s, 1, pps->b_weighted_pred );
     bs_write( s, 2, pps->b_weighted_bipred );