Unified approach for backward probability update.

Replacing update_mode_probs() and adapt_probs() with tree_merge_probs().

Change-Id: I50b2c968d67c9265f5216c700cbeba25fb014654

3 files changed, 88 insertions, 80 deletions

diff --git a/vp9/common/vp9_entropymode.c b/vp9/common/vp9_entropymode.c
index c4d7c38d0..a963d55e6 100644
--- a/vp9/common/vp9_entropymode.c
+++ b/vp9/common/vp9_entropymode.c
@@ -350,23 +350,15 @@ void vp9_entropy_mode_init() {
 #define COUNT_SAT 20
 #define MAX_UPDATE_FACTOR 128
 
-static int update_ct(vp9_prob pre_prob, const unsigned int ct[2]) {
+static int adapt_prob(vp9_prob pre_prob, const unsigned int ct[2]) {
   return merge_probs(pre_prob, ct, COUNT_SAT, MAX_UPDATE_FACTOR);
 }
 
-static void update_mode_probs(int n_modes,
-                              const vp9_tree_index *tree,
-                              const unsigned int *cnt,
-                              const vp9_prob *pre_probs, vp9_prob *dst_probs,
-                              unsigned int tok0_offset) {
-#define MAX_PROBS 32
-  unsigned int branch_ct[MAX_PROBS][2];
-  int t;
-
-  assert(n_modes - 1 < MAX_PROBS);
-  vp9_tree_probs_from_distribution(tree, branch_ct, cnt, tok0_offset);
-  for (t = 0; t < n_modes - 1; ++t)
-    dst_probs[t] = update_ct(pre_probs[t], branch_ct[t]);
+static void adapt_probs(const vp9_tree_index *tree,
+                        const vp9_prob *pre_probs, const unsigned int *counts,
+                        unsigned int offset, vp9_prob *probs) {
+  tree_merge_probs(tree, pre_probs, counts, offset,
+                   COUNT_SAT, MAX_UPDATE_FACTOR, probs);
 }
 
 void vp9_adapt_mode_probs(VP9_COMMON *cm) {
@@ -376,44 +368,40 @@ void vp9_adapt_mode_probs(VP9_COMMON *cm) {
   const FRAME_COUNTS *counts = &cm->counts;
 
   for (i = 0; i < INTRA_INTER_CONTEXTS; i++)
-    fc->intra_inter_prob[i] = update_ct(pre_fc->intra_inter_prob[i],
-                                        counts->intra_inter[i]);
+    fc->intra_inter_prob[i] = adapt_prob(pre_fc->intra_inter_prob[i],
+                                         counts->intra_inter[i]);
   for (i = 0; i < COMP_INTER_CONTEXTS; i++)
-    fc->comp_inter_prob[i] = update_ct(pre_fc->comp_inter_prob[i],
-                                       counts->comp_inter[i]);
+    fc->comp_inter_prob[i] = adapt_prob(pre_fc->comp_inter_prob[i],
+                                        counts->comp_inter[i]);
   for (i = 0; i < REF_CONTEXTS; i++)
-    fc->comp_ref_prob[i] = update_ct(pre_fc->comp_ref_prob[i],
-                                     counts->comp_ref[i]);
+    fc->comp_ref_prob[i] = adapt_prob(pre_fc->comp_ref_prob[i],
+                                      counts->comp_ref[i]);
   for (i = 0; i < REF_CONTEXTS; i++)
     for (j = 0; j < 2; j++)
-      fc->single_ref_prob[i][j] = update_ct(pre_fc->single_ref_prob[i][j],
-                                            counts->single_ref[i][j]);
+      fc->single_ref_prob[i][j] = adapt_prob(pre_fc->single_ref_prob[i][j],
+                                             counts->single_ref[i][j]);
 
   for (i = 0; i < INTER_MODE_CONTEXTS; i++)
-    update_mode_probs(INTER_MODES, vp9_inter_mode_tree,
-                      counts->inter_mode[i], pre_fc->inter_mode_probs[i],
-                      fc->inter_mode_probs[i], NEARESTMV);
+    adapt_probs(vp9_inter_mode_tree, pre_fc->inter_mode_probs[i],
+                counts->inter_mode[i], NEARESTMV, fc->inter_mode_probs[i]);
 
   for (i = 0; i < BLOCK_SIZE_GROUPS; i++)
-    update_mode_probs(INTRA_MODES, vp9_intra_mode_tree,
-                      counts->y_mode[i], pre_fc->y_mode_prob[i],
-                      fc->y_mode_prob[i], 0);
+    adapt_probs(vp9_intra_mode_tree, pre_fc->y_mode_prob[i],
+                counts->y_mode[i], 0, fc->y_mode_prob[i]);
 
   for (i = 0; i < INTRA_MODES; ++i)
-    update_mode_probs(INTRA_MODES, vp9_intra_mode_tree,
-                      counts->uv_mode[i], pre_fc->uv_mode_prob[i],
-                      fc->uv_mode_prob[i], 0);
+    adapt_probs(vp9_intra_mode_tree, pre_fc->uv_mode_prob[i],
+                counts->uv_mode[i], 0, fc->uv_mode_prob[i]);
 
   for (i = 0; i < PARTITION_CONTEXTS; i++)
-    update_mode_probs(PARTITION_TYPES, vp9_partition_tree, counts->partition[i],
-                      pre_fc->partition_prob[i], fc->partition_prob[i], 0);
+    adapt_probs(vp9_partition_tree, pre_fc->partition_prob[i],
+                counts->partition[i], 0, fc->partition_prob[i]);
 
   if (cm->mcomp_filter_type == SWITCHABLE) {
     for (i = 0; i < SWITCHABLE_FILTER_CONTEXTS; i++)
-      update_mode_probs(SWITCHABLE_FILTERS, vp9_switchable_interp_tree,
-                        counts->switchable_interp[i],
-                        pre_fc->switchable_interp_prob[i],
-                        fc->switchable_interp_prob[i], 0);
+      adapt_probs(vp9_switchable_interp_tree, pre_fc->switchable_interp_prob[i],
+                  counts->switchable_interp[i], 0,
+                  fc->switchable_interp_prob[i]);
   }
 
   if (cm->tx_mode == TX_MODE_SELECT) {
@@ -425,23 +413,24 @@ void vp9_adapt_mode_probs(VP9_COMMON *cm) {
     for (i = 0; i < TX_SIZE_CONTEXTS; ++i) {
       tx_counts_to_branch_counts_8x8(counts->tx.p8x8[i], branch_ct_8x8p);
       for (j = 0; j < TX_SIZES - 3; ++j)
-        fc->tx_probs.p8x8[i][j] = update_ct(pre_fc->tx_probs.p8x8[i][j],
-                                            branch_ct_8x8p[j]);
+        fc->tx_probs.p8x8[i][j] = adapt_prob(pre_fc->tx_probs.p8x8[i][j],
+                                             branch_ct_8x8p[j]);
 
       tx_counts_to_branch_counts_16x16(counts->tx.p16x16[i], branch_ct_16x16p);
       for (j = 0; j < TX_SIZES - 2; ++j)
-        fc->tx_probs.p16x16[i][j] = update_ct(pre_fc->tx_probs.p16x16[i][j],
-                                              branch_ct_16x16p[j]);
+        fc->tx_probs.p16x16[i][j] = adapt_prob(pre_fc->tx_probs.p16x16[i][j],
+                                               branch_ct_16x16p[j]);
 
       tx_counts_to_branch_counts_32x32(counts->tx.p32x32[i], branch_ct_32x32p);
       for (j = 0; j < TX_SIZES - 1; ++j)
-        fc->tx_probs.p32x32[i][j] = update_ct(pre_fc->tx_probs.p32x32[i][j],
-                                              branch_ct_32x32p[j]);
+        fc->tx_probs.p32x32[i][j] = adapt_prob(pre_fc->tx_probs.p32x32[i][j],
+                                               branch_ct_32x32p[j]);
     }
   }
 
   for (i = 0; i < MBSKIP_CONTEXTS; ++i)
-    fc->mbskip_probs[i] = update_ct(pre_fc->mbskip_probs[i], counts->mbskip[i]);
+    fc->mbskip_probs[i] = adapt_prob(pre_fc->mbskip_probs[i],
+                                     counts->mbskip[i]);
 }
 
 static void set_default_lf_deltas(struct loopfilter *lf) {
diff --git a/vp9/common/vp9_entropymv.c b/vp9/common/vp9_entropymv.c
index 3ebb701a7..b061cdb38 100644
--- a/vp9/common/vp9_entropymv.c
+++ b/vp9/common/vp9_entropymv.c
@@ -194,57 +194,44 @@ static vp9_prob adapt_prob(vp9_prob prep, const unsigned int ct[2]) {
   return merge_probs(prep, ct, MV_COUNT_SAT, MV_MAX_UPDATE_FACTOR);
 }
 
-static unsigned int adapt_probs(unsigned int i,
-                                vp9_tree tree,
-                                vp9_prob this_probs[],
-                                const vp9_prob last_probs[],
-                                const unsigned int num_events[]) {
-  const unsigned int left = tree[i] <= 0
-          ? num_events[-tree[i]]
-          : adapt_probs(tree[i], tree, this_probs, last_probs, num_events);
-
-  const unsigned int right = tree[i + 1] <= 0
-          ? num_events[-tree[i + 1]]
-          : adapt_probs(tree[i + 1], tree, this_probs, last_probs, num_events);
-  const unsigned int ct[2] = { left, right };
-  this_probs[i >> 1] = adapt_prob(last_probs[i >> 1], ct);
-  return left + right;
+static void adapt_probs(const vp9_tree_index *tree, const vp9_prob *pre_probs,
+                        const unsigned int *counts, vp9_prob *probs) {
+  tree_merge_probs(tree, pre_probs, counts, 0,
+                   MV_COUNT_SAT, MV_MAX_UPDATE_FACTOR, probs);
 }
 
-
 void vp9_adapt_mv_probs(VP9_COMMON *cm, int allow_hp) {
   int i, j;
 
-  const FRAME_CONTEXT *pre_fc = &cm->frame_contexts[cm->frame_context_idx];
-
-  nmv_context *ctx = &cm->fc.nmvc;
-  const nmv_context *pre_ctx = &pre_fc->nmvc;
-  const nmv_context_counts *cts = &cm->counts.mv;
+  nmv_context *fc = &cm->fc.nmvc;
+  const nmv_context *pre_fc = &cm->frame_contexts[cm->frame_context_idx].nmvc;
+  const nmv_context_counts *counts = &cm->counts.mv;
 
-  adapt_probs(0, vp9_mv_joint_tree, ctx->joints, pre_ctx->joints, cts->joints);
+  adapt_probs(vp9_mv_joint_tree, pre_fc->joints, counts->joints,
+                     fc->joints);
 
   for (i = 0; i < 2; ++i) {
-    ctx->comps[i].sign = adapt_prob(pre_ctx->comps[i].sign, cts->comps[i].sign);
-    adapt_probs(0, vp9_mv_class_tree, ctx->comps[i].classes,
-                pre_ctx->comps[i].classes, cts->comps[i].classes);
-    adapt_probs(0, vp9_mv_class0_tree, ctx->comps[i].class0,
-                pre_ctx->comps[i].class0, cts->comps[i].class0);
+    nmv_component *comp = &fc->comps[i];
+    const nmv_component *pre_comp = &pre_fc->comps[i];
+    const nmv_component_counts *c = &counts->comps[i];
+
+    comp->sign = adapt_prob(pre_comp->sign, c->sign);
+    adapt_probs(vp9_mv_class_tree, pre_comp->classes, c->classes,
+                comp->classes);
+    adapt_probs(vp9_mv_class0_tree, pre_comp->class0, c->class0, comp->class0);
 
     for (j = 0; j < MV_OFFSET_BITS; ++j)
-        ctx->comps[i].bits[j] = adapt_prob(pre_ctx->comps[i].bits[j],
-                                           cts->comps[i].bits[j]);
+      comp->bits[j] = adapt_prob(pre_comp->bits[j], c->bits[j]);
 
     for (j = 0; j < CLASS0_SIZE; ++j)
-      adapt_probs(0, vp9_mv_fp_tree, ctx->comps[i].class0_fp[j],
-                  pre_ctx->comps[i].class0_fp[j], cts->comps[i].class0_fp[j]);
+      adapt_probs(vp9_mv_fp_tree, pre_comp->class0_fp[j], c->class0_fp[j],
+                  comp->class0_fp[j]);
 
-    adapt_probs(0, vp9_mv_fp_tree, ctx->comps[i].fp, pre_ctx->comps[i].fp,
-                cts->comps[i].fp);
+    adapt_probs(vp9_mv_fp_tree, pre_comp->fp, c->fp, comp->fp);
 
     if (allow_hp) {
-      ctx->comps[i].class0_hp = adapt_prob(pre_ctx->comps[i].class0_hp,
-                                           cts->comps[i].class0_hp);
-      ctx->comps[i].hp = adapt_prob(pre_ctx->comps[i].hp, cts->comps[i].hp);
+      comp->class0_hp = adapt_prob(pre_comp->class0_hp, c->class0_hp);
+      comp->hp = adapt_prob(pre_comp->hp, c->hp);
     }
   }
 }
diff --git a/vp9/common/vp9_treecoder.h b/vp9/common/vp9_treecoder.h
index 3cc9ce198..9c776d61c 100644
--- a/vp9/common/vp9_treecoder.h
+++ b/vp9/common/vp9_treecoder.h
@@ -91,5 +91,37 @@ static INLINE vp9_prob merge_probs(vp9_prob pre_prob,
   return weighted_prob(pre_prob, prob, factor);
 }
 
+static unsigned int tree_merge_probs_impl(unsigned int i,
+                                          const vp9_tree_index *tree,
+                                          const vp9_prob *pre_probs,
+                                          const unsigned int *counts,
+                                          unsigned int count_sat,
+                                          unsigned int max_update_factor,
+                                          vp9_prob *probs) {
+  const int l = tree[i];
+  const unsigned int left_count = (l <= 0)
+                 ? counts[-l]
+                 : tree_merge_probs_impl(l, tree, pre_probs, counts,
+                                         count_sat, max_update_factor, probs);
+  const int r = tree[i + 1];
+  const unsigned int right_count = (r <= 0)
+                 ? counts[-r]
+                 : tree_merge_probs_impl(r, tree, pre_probs, counts,
+                                         count_sat, max_update_factor, probs);
+  const unsigned int ct[2] = { left_count, right_count };
+  probs[i >> 1] = merge_probs(pre_probs[i >> 1], ct,
+                              count_sat, max_update_factor);
+  return left_count + right_count;
+}
+
+static void tree_merge_probs(const vp9_tree_index *tree,
+                             const vp9_prob *pre_probs,
+                             const unsigned int *counts, int offset,
+                             unsigned int count_sat,
+                             unsigned int max_update_factor, vp9_prob *probs) {
+  tree_merge_probs_impl(0, tree, pre_probs, &counts[-offset],
+                        count_sat, max_update_factor, probs);
+}
+
 
 #endif  // VP9_COMMON_VP9_TREECODER_H_