Merge "Dual ARF changes: Buffer index selection."

1 files changed, 48 insertions, 32 deletions

diff --git a/vp9/encoder/vp9_firstpass.c b/vp9/encoder/vp9_firstpass.c
index f2e89b819..6fb263fd6 100644
--- a/vp9/encoder/vp9_firstpass.c
+++ b/vp9/encoder/vp9_firstpass.c
@@ -1282,6 +1282,18 @@ static int calculate_boost_bits(int frame_count,
   return MAX((int)(((int64_t)boost * total_group_bits) / allocation_chunks), 0);
 }
 
+// Current limit on maximum number of active arfs in a GF/ARF group.
+#define MAX_ACTIVE_ARFS 2
+#define ARF_SLOT1 2
+#define ARF_SLOT2 3
+// This function indirects the choice of buffers for arfs.
+// At the moment the values are fixed but this may change as part of
+// the integration process with other codec features that swap buffers around.
+static void get_arf_buffer_indices(unsigned char *arf_buffer_indices) {
+  arf_buffer_indices[0] = ARF_SLOT1;
+  arf_buffer_indices[1] = ARF_SLOT2;
+}
+
 static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
                                    double group_error, int gf_arf_bits) {
   RATE_CONTROL *const rc = &cpi->rc;
@@ -1298,10 +1310,13 @@ static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
   double err_fraction;
   int mid_boost_bits = 0;
   int middle_frame_idx;
+  unsigned char arf_buffer_indices[MAX_ACTIVE_ARFS];
 
   key_frame = cpi->common.frame_type == KEY_FRAME ||
               vp9_is_upper_layer_key_frame(cpi);
 
+  get_arf_buffer_indices(arf_buffer_indices);
+
   // For key frames the frame target rate is already set and it
   // is also the golden frame.
   if (!key_frame) {
@@ -1309,14 +1324,14 @@ static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
       twopass->gf_group.update_type[0] = OVERLAY_UPDATE;
       twopass->gf_group.rf_level[0] = INTER_NORMAL;
       twopass->gf_group.bit_allocation[0] = 0;
-      twopass->gf_group.arf_update_idx[0] = 2;
-      twopass->gf_group.arf_ref_idx[0] = 2;
+      twopass->gf_group.arf_update_idx[0] = arf_buffer_indices[0];
+      twopass->gf_group.arf_ref_idx[0] = arf_buffer_indices[0];
     } else {
       twopass->gf_group.update_type[0] = GF_UPDATE;
       twopass->gf_group.rf_level[0] = GF_ARF_STD;
       twopass->gf_group.bit_allocation[0] = gf_arf_bits;
-      twopass->gf_group.arf_update_idx[0] = 2;
-      twopass->gf_group.arf_ref_idx[0] = 2;
+      twopass->gf_group.arf_update_idx[0] = arf_buffer_indices[0];
+      twopass->gf_group.arf_ref_idx[0] = arf_buffer_indices[0];
     }
 
     // Step over the golden frame / overlay frame
@@ -1331,18 +1346,20 @@ static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
 
   // Store the bits to spend on the ARF if there is one.
   if (rc->source_alt_ref_pending) {
-    // A portion of the gf / arf extra bits are set asside for lower level
-    // boosted frames in the middle of the group.
-    mid_boost_bits = gf_arf_bits >> 5;
-    gf_arf_bits -= (gf_arf_bits >> 5);
+    if (cpi->multi_arf_enabled) {
+      // A portion of the gf / arf extra bits are set asside for lower level
+      // boosted frames in the middle of the group.
+      mid_boost_bits += gf_arf_bits >> 5;
+      gf_arf_bits -= (gf_arf_bits >> 5);
+    }
 
     twopass->gf_group.update_type[frame_index] = ARF_UPDATE;
     twopass->gf_group.rf_level[frame_index] = GF_ARF_STD;
     twopass->gf_group.bit_allocation[frame_index] = gf_arf_bits;
     twopass->gf_group.arf_src_offset[frame_index] =
       (unsigned char)(rc->baseline_gf_interval - 1);
-    twopass->gf_group.arf_update_idx[frame_index] = 2;
-    twopass->gf_group.arf_ref_idx[frame_index] = 2;
+    twopass->gf_group.arf_update_idx[frame_index] = arf_buffer_indices[0];
+    twopass->gf_group.arf_ref_idx[frame_index] = arf_buffer_indices[0];
     ++frame_index;
 
     if (cpi->multi_arf_enabled) {
@@ -1351,8 +1368,8 @@ static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
       twopass->gf_group.rf_level[frame_index] = GF_ARF_LOW;
       twopass->gf_group.arf_src_offset[frame_index] =
         (unsigned char)((rc->baseline_gf_interval >> 1) - 1);
-      twopass->gf_group.arf_update_idx[frame_index] = 3;
-      twopass->gf_group.arf_ref_idx[frame_index] = 2;
+      twopass->gf_group.arf_update_idx[frame_index] = arf_buffer_indices[1];
+      twopass->gf_group.arf_ref_idx[frame_index] = arf_buffer_indices[0];
       ++frame_index;
     }
   }
@@ -1362,6 +1379,7 @@ static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
 
   // Allocate bits to the other frames in the group.
   for (i = 0; i < rc->baseline_gf_interval - 1; ++i) {
+    int arf_idx = 0;
     if (EOF == input_stats(twopass, &frame_stats))
       break;
 
@@ -1378,17 +1396,11 @@ static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
       mid_boost_bits += (target_frame_size >> 4);
       target_frame_size -= (target_frame_size >> 4);
 
-      if (frame_index <= middle_frame_idx) {
-        twopass->gf_group.arf_update_idx[frame_index] = 3;
-        twopass->gf_group.arf_ref_idx[frame_index] = 3;
-      } else {
-        twopass->gf_group.arf_update_idx[frame_index] = 2;
-        twopass->gf_group.arf_ref_idx[frame_index] = 2;
-      }
-    } else {
-      twopass->gf_group.arf_update_idx[frame_index] = 2;
-      twopass->gf_group.arf_ref_idx[frame_index] = 2;
+      if (frame_index <= middle_frame_idx)
+        arf_idx = 1;
     }
+    twopass->gf_group.arf_update_idx[frame_index] = arf_buffer_indices[arf_idx];
+    twopass->gf_group.arf_ref_idx[frame_index] = arf_buffer_indices[arf_idx];
 
     target_frame_size = clamp(target_frame_size, 0,
                               MIN(max_bits, (int)total_group_bits));
@@ -1400,23 +1412,27 @@ static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
     ++frame_index;
   }
 
+  // Note:
+  // We need to configure the frame at the end of the sequence + 1 that will be
+  // the start frame for the next group. Otherwise prior to the call to
+  // vp9_rc_get_second_pass_params() the data will be undefined.
+  twopass->gf_group.arf_update_idx[frame_index] = arf_buffer_indices[0];
+  twopass->gf_group.arf_ref_idx[frame_index] = arf_buffer_indices[0];
+
   if (rc->source_alt_ref_pending) {
+    twopass->gf_group.update_type[frame_index] = OVERLAY_UPDATE;
+    twopass->gf_group.rf_level[frame_index] = INTER_NORMAL;
+
+    // Final setup for second arf and its overlay.
     if (cpi->multi_arf_enabled) {
       twopass->gf_group.bit_allocation[2] =
         twopass->gf_group.bit_allocation[middle_frame_idx] + mid_boost_bits;
       twopass->gf_group.update_type[middle_frame_idx] = OVERLAY_UPDATE;
       twopass->gf_group.bit_allocation[middle_frame_idx] = 0;
     }
-
-    // Configure the overlay frame at the end of the sequence that will also
-    // be the start frame of the next group. The reason for doing this here
-    // is that on entry to vp9_get_compressed_data() for the overlay
-    // frame, but before the call to vp9_rc_get_second_pass_params() the
-    // data will otherwise be undefined.
-    twopass->gf_group.update_type[frame_index] = OVERLAY_UPDATE;
-    twopass->gf_group.rf_level[frame_index] = INTER_NORMAL;
-    twopass->gf_group.arf_update_idx[frame_index] = 2;
-    twopass->gf_group.arf_ref_idx[frame_index] = 2;
+  } else {
+    twopass->gf_group.update_type[frame_index] = GF_UPDATE;
+    twopass->gf_group.rf_level[frame_index] = GF_ARF_STD;
   }
 }