Entropy coding for dynamic ref mv modes

This commit enables entropy coding for dynamic reference motion
vector modes. The probability model is contexted on the ranking
categories of the reference motion vector candidates.

Change-Id: I09b58d98a409d63ec1a407331e29f8945b7ef17d

vp10/common/entropymode.c

@@ -184,6 +184,10 @@ static const vpx_prob default_refmv_prob[REFMV_MODE_CONTEXTS] = {
     220, 220, 200, 200, 180, 128, 30, 220, 30,
 };
 
+static const vpx_prob default_drl_prob[DRL_MODE_CONTEXTS] = {
+    128, 128, 128,
+};
+
 #if CONFIG_EXT_INTER
 static const vpx_prob default_new2mv_prob = 180;
 #endif
@@ -1292,6 +1296,8 @@ static void init_mode_probs(FRAME_CONTEXT *fc) {
   vp10_copy(fc->newmv_prob, default_newmv_prob);
   vp10_copy(fc->zeromv_prob, default_zeromv_prob);
   vp10_copy(fc->refmv_prob, default_refmv_prob);
+  vp10_copy(fc->drl_prob0, default_drl_prob);
+  vp10_copy(fc->drl_prob1, default_drl_prob);
 #if CONFIG_EXT_INTER
   fc->new2mv_prob = default_new2mv_prob;
 #endif  // CONFIG_EXT_INTER
@@ -1360,6 +1366,13 @@ void vp10_adapt_inter_frame_probs(VP10_COMMON *cm) {
     fc->refmv_prob[i] = mode_mv_merge_probs(pre_fc->refmv_prob[i],
                                             counts->refmv_mode[i]);
 
+  for (i = 0; i < DRL_MODE_CONTEXTS; ++i)
+    fc->drl_prob0[i] = mode_mv_merge_probs(pre_fc->drl_prob0[i],
+                                           counts->drl_mode0[i]);
+  for (i = 0; i < DRL_MODE_CONTEXTS; ++i)
+    fc->drl_prob1[i] = mode_mv_merge_probs(pre_fc->drl_prob1[i],
+                                           counts->drl_mode1[i]);
+
 #if CONFIG_EXT_INTER
   fc->new2mv_prob = mode_mv_merge_probs(pre_fc->new2mv_prob,
                                         counts->new2mv_mode);

vp10/common/entropymode.h

@@ -68,6 +68,9 @@ typedef struct frame_contexts {
   vpx_prob newmv_prob[NEWMV_MODE_CONTEXTS];
   vpx_prob zeromv_prob[ZEROMV_MODE_CONTEXTS];
   vpx_prob refmv_prob[REFMV_MODE_CONTEXTS];
+  vpx_prob drl_prob0[DRL_MODE_CONTEXTS];
+  vpx_prob drl_prob1[DRL_MODE_CONTEXTS];
+
 #if CONFIG_EXT_INTER
   vpx_prob new2mv_prob;
 #endif  // CONFIG_EXT_INTER
@@ -121,6 +124,8 @@ typedef struct FRAME_COUNTS {
   unsigned int newmv_mode[NEWMV_MODE_CONTEXTS][2];
   unsigned int zeromv_mode[ZEROMV_MODE_CONTEXTS][2];
   unsigned int refmv_mode[REFMV_MODE_CONTEXTS][2];
+  unsigned int drl_mode0[DRL_MODE_CONTEXTS][2];
+  unsigned int drl_mode1[DRL_MODE_CONTEXTS][2];
 #if CONFIG_EXT_INTER
   unsigned int new2mv_mode[2];
 #endif  // CONFIG_EXT_INTER

vp10/common/enums.h

@@ -231,6 +231,7 @@ typedef enum {
 #define NEWMV_MODE_CONTEXTS  7
 #define ZEROMV_MODE_CONTEXTS 2
 #define REFMV_MODE_CONTEXTS  9
+#define DRL_MODE_CONTEXTS    3
 
 #define ZEROMV_OFFSET 3
 #define REFMV_OFFSET  4
@@ -251,6 +252,7 @@ typedef enum {
 #define MAX_MV_REF_CANDIDATES 2
 #if CONFIG_REF_MV
 #define MAX_REF_MV_STACK_SIZE 16
+#define REF_CAT_LEVEL  160
 #endif
 
 #define INTRA_INTER_CONTEXTS 4

vp10/common/mvref_common.c

@@ -329,6 +329,9 @@ static void setup_ref_mv_list(const VP10_COMMON *cm, const MACROBLOCKD *xd,
 
   nearest_refmv_count = *refmv_count;
 
+  for (idx = 0; idx < nearest_refmv_count; ++idx)
+    ref_mv_stack[idx].weight += REF_CAT_LEVEL;
+
   if (prev_frame_mvs_base && cm->show_frame && cm->last_show_frame
       && rf[1] == NONE) {
     int ref;

vp10/common/mvref_common.h

@@ -257,6 +257,24 @@ static INLINE int16_t vp10_mode_context_analyzer(
   else
     return mode_context[rf[0]];
 }
+
+static INLINE uint8_t vp10_drl_ctx(const CANDIDATE_MV *ref_mv_stack,
+                                   int ref_idx) {
+  if (ref_mv_stack[ref_idx + 1].weight > REF_CAT_LEVEL &&
+      ref_mv_stack[ref_idx + 2].weight > REF_CAT_LEVEL)
+    return 0;
+
+  if (ref_mv_stack[ref_idx + 1].weight > REF_CAT_LEVEL &&
+      ref_mv_stack[ref_idx + 2].weight < REF_CAT_LEVEL)
+    return 1;
+
+  if (ref_mv_stack[ref_idx + 1].weight < REF_CAT_LEVEL &&
+      ref_mv_stack[ref_idx + 2].weight < REF_CAT_LEVEL)
+    return 2;
+
+  assert(0);
+  return 0;
+}
 #endif
 
 typedef void (*find_mv_refs_sync)(void *const data, int mi_row);

vp10/common/thread_common.c

@@ -379,6 +379,15 @@ void vp10_accumulate_frame_counts(VP10_COMMON *cm, FRAME_COUNTS *counts,
     for (j = 0; j < 2; ++j)
       cm->counts.refmv_mode[i][j] += counts->refmv_mode[i][j];
 
+
+  for (i = 0; i < DRL_MODE_CONTEXTS; ++i)
+    for (j = 0; j < 2; ++j)
+      cm->counts.drl_mode0[i][j] += counts->drl_mode0[i][j];
+
+  for (i = 0; i < DRL_MODE_CONTEXTS; ++i)
+    for (j = 0; j < 2; ++j)
+      cm->counts.drl_mode1[i][j] += counts->drl_mode1[i][j];
+
 #if CONFIG_EXT_INTER
   for (j = 0; j < 2; ++j)
     cm->counts.new2mv_mode[j] += counts->new2mv_mode[j];

vp10/decoder/decodeframe.c

@@ -132,6 +132,10 @@ static void read_inter_mode_probs(FRAME_CONTEXT *fc, vpx_reader *r) {
     vp10_diff_update_prob(r, &fc->zeromv_prob[i]);
   for (i = 0; i < REFMV_MODE_CONTEXTS; ++i)
     vp10_diff_update_prob(r, &fc->refmv_prob[i]);
+  for (i = 0; i < DRL_MODE_CONTEXTS; ++i)
+    vp10_diff_update_prob(r, &fc->drl_prob0[i]);
+  for (i = 0; i < DRL_MODE_CONTEXTS; ++i)
+    vp10_diff_update_prob(r, &fc->drl_prob1[i]);
 #if CONFIG_EXT_INTER
   vp10_diff_update_prob(r, &fc->new2mv_prob);
 #endif  // CONFIG_EXT_INTER

vp10/decoder/decodemv.c

@@ -147,6 +147,45 @@ static PREDICTION_MODE read_inter_mode(VP10_COMMON *cm, MACROBLOCKD *xd,
 #endif
 }
 
+#if CONFIG_REF_MV
+static void read_drl_idx(const VP10_COMMON *cm,
+                         MACROBLOCKD *xd,
+                         MB_MODE_INFO *mbmi,
+                         vpx_reader *r) {
+  uint8_t ref_frame_type = vp10_ref_frame_type(mbmi->ref_frame);
+  mbmi->ref_mv_idx = 0;
+
+  if (xd->ref_mv_count[ref_frame_type] > 2) {
+    uint8_t drl0_ctx = vp10_drl_ctx(xd->ref_mv_stack[ref_frame_type], 0);
+    vpx_prob drl0_prob = cm->fc->drl_prob0[drl0_ctx];
+    if (vpx_read(r, drl0_prob)) {
+      mbmi->ref_mv_idx = 1;
+      if (xd->counts)
+        ++xd->counts->drl_mode0[drl0_ctx][1];
+      if (xd->ref_mv_count[ref_frame_type] > 3) {
+        uint8_t drl1_ctx =
+            vp10_drl_ctx(xd->ref_mv_stack[ref_frame_type], 1);
+        vpx_prob drl1_prob = cm->fc->drl_prob1[drl1_ctx];
+        if (vpx_read(r, drl1_prob)) {
+          mbmi->ref_mv_idx = 2;
+          if (xd->counts)
+            ++xd->counts->drl_mode1[drl1_ctx][1];
+
+          return;
+        }
+
+        if (xd->counts)
+          ++xd->counts->drl_mode1[drl1_ctx][0];
+      }
+      return;
+    }
+
+    if (xd->counts)
+      ++xd->counts->drl_mode0[drl0_ctx][0];
+  }
+}
+#endif
+
 #if CONFIG_EXT_INTER
 static PREDICTION_MODE read_inter_compound_mode(VP10_COMMON *cm,
                                                 MACROBLOCKD *xd,
@@ -1056,17 +1095,8 @@ static void read_inter_block_mode_info(VP10Decoder *const pbi,
 #endif  // CONFIG_REF_MV && CONFIG_EXT_INTER
                                    r, mode_ctx);
 #if CONFIG_REF_MV
-      if (mbmi->mode == NEARMV) {
-        uint8_t ref_frame_type = vp10_ref_frame_type(mbmi->ref_frame);
-        if (xd->ref_mv_count[ref_frame_type] > 2) {
-          if (vpx_read_bit(r)) {
-            mbmi->ref_mv_idx = 1;
-            if (xd->ref_mv_count[ref_frame_type] > 3)
-              if (vpx_read_bit(r))
-                mbmi->ref_mv_idx = 2;
-          }
-        }
-      }
+      if (mbmi->mode == NEARMV)
+        read_drl_idx(cm, xd, mbmi, r);
 #endif
     }
   }

vp10/encoder/bitstream.c

@@ -177,6 +177,28 @@ static void write_inter_mode(VP10_COMMON *cm,
 #endif
 }
 
+#if CONFIG_REF_MV
+static void write_drl_idx(const VP10_COMMON *cm,
+                          const MB_MODE_INFO *mbmi,
+                          const MB_MODE_INFO_EXT *mbmi_ext,
+                          vpx_writer *w) {
+  uint8_t ref_frame_type = vp10_ref_frame_type(mbmi->ref_frame);
+  if (mbmi_ext->ref_mv_count[ref_frame_type] > 2) {
+    uint8_t drl0_ctx =
+        vp10_drl_ctx(mbmi_ext->ref_mv_stack[ref_frame_type], 0);
+    vpx_prob drl0_prob = cm->fc->drl_prob0[drl0_ctx];
+    vpx_write(w, mbmi->ref_mv_idx != 0, drl0_prob);
+    if (mbmi_ext->ref_mv_count[ref_frame_type] > 3 &&
+        mbmi->ref_mv_idx > 0) {
+      uint8_t drl1_ctx =
+          vp10_drl_ctx(mbmi_ext->ref_mv_stack[ref_frame_type], 1);
+      vpx_prob drl1_prob = cm->fc->drl_prob1[drl1_ctx];
+      vpx_write(w, mbmi->ref_mv_idx != 1, drl1_prob);
+    }
+  }
+}
+#endif
+
 #if CONFIG_EXT_INTER
 static void write_inter_compound_mode(VP10_COMMON *cm, vpx_writer *w,
                                       PREDICTION_MODE mode,
@@ -312,7 +334,12 @@ static void update_inter_mode_probs(VP10_COMMON *cm, vpx_writer *w,
   for (i = 0; i < REFMV_MODE_CONTEXTS; ++i)
     vp10_cond_prob_diff_update(w, &cm->fc->refmv_prob[i],
                                counts->refmv_mode[i]);
-
+  for (i = 0; i < DRL_MODE_CONTEXTS; ++i)
+    vp10_cond_prob_diff_update(w, &cm->fc->drl_prob0[i],
+                               counts->drl_mode0[i]);
+  for (i = 0; i < DRL_MODE_CONTEXTS; ++i)
+    vp10_cond_prob_diff_update(w, &cm->fc->drl_prob1[i],
+                               counts->drl_mode1[i]);
 #if CONFIG_EXT_INTER
   vp10_cond_prob_diff_update(w, &cm->fc->new2mv_prob, counts->new2mv_mode);
 #endif  // CONFIG_EXT_INTER
@@ -994,15 +1021,8 @@ static void pack_inter_mode_mvs(VP10_COMP *cpi, const MODE_INFO *mi,
                          mode_ctx);
 
 #if CONFIG_REF_MV
-        if (mode == NEARMV) {
-          uint8_t ref_frame_type = vp10_ref_frame_type(mbmi->ref_frame);
-          if (mbmi_ext->ref_mv_count[ref_frame_type] > 2) {
-            vpx_write_bit(w, mbmi->ref_mv_idx != 0);
-            if (mbmi_ext->ref_mv_count[ref_frame_type] > 3 &&
-                mbmi->ref_mv_idx > 0)
-              vpx_write_bit(w, mbmi->ref_mv_idx != 1);
-          }
-        }
+        if (mode == NEARMV)
+          write_drl_idx(cm, mbmi, mbmi_ext, w);
 #endif
       }
     }

vp10/encoder/encodeframe.c

@@ -1822,6 +1822,28 @@ static void update_stats(VP10_COMMON *cm, ThreadData *td
                                 has_second_ref(mbmi),
 #endif  // CONFIG_EXT_INTER
                                 mode_ctx);
+
+        if (mode == NEARMV) {
+          uint8_t ref_frame_type = vp10_ref_frame_type(mbmi->ref_frame);
+          if (mbmi_ext->ref_mv_count[ref_frame_type] > 2) {
+            uint8_t drl0_ctx =
+                vp10_drl_ctx(mbmi_ext->ref_mv_stack[ref_frame_type], 0);
+            if (mbmi->ref_mv_idx == 0)
+              ++counts->drl_mode0[drl0_ctx][0];
+            else
+              ++counts->drl_mode0[drl0_ctx][1];
+
+            if (mbmi_ext->ref_mv_count[ref_frame_type] > 3 &&
+                mbmi->ref_mv_idx > 0) {
+              uint8_t drl1_ctx =
+                  vp10_drl_ctx(mbmi_ext->ref_mv_stack[ref_frame_type], 1);
+              if (mbmi->ref_mv_idx == 1)
+                ++counts->drl_mode1[drl1_ctx][0];
+              else
+                ++counts->drl_mode1[drl1_ctx][1];
+            }
+          }
+        }
 #if CONFIG_EXT_INTER
         }
 #endif  // CONFIG_EXT_INTER

vp10/encoder/encoder.h

@@ -474,6 +474,8 @@ typedef struct VP10_COMP {
   int newmv_mode_cost[NEWMV_MODE_CONTEXTS][2];
   int zeromv_mode_cost[ZEROMV_MODE_CONTEXTS][2];
   int refmv_mode_cost[REFMV_MODE_CONTEXTS][2];
+  int drl_mode_cost0[DRL_MODE_CONTEXTS][2];
+  int drl_mode_cost1[DRL_MODE_CONTEXTS][2];
 #if CONFIG_EXT_INTER
   int new2mv_mode_cost[2];
 #endif  // CONFIG_EXT_INTER

vp10/encoder/rd.c

@@ -382,6 +382,16 @@ void vp10_initialize_rd_consts(VP10_COMP *cpi) {
       cpi->refmv_mode_cost[i][0] = vp10_cost_bit(cm->fc->refmv_prob[i], 0);
       cpi->refmv_mode_cost[i][1] = vp10_cost_bit(cm->fc->refmv_prob[i], 1);
     }
+
+    for (i = 0; i < DRL_MODE_CONTEXTS; ++i) {
+      cpi->drl_mode_cost0[i][0] = vp10_cost_bit(cm->fc->drl_prob0[i], 0);
+      cpi->drl_mode_cost0[i][1] = vp10_cost_bit(cm->fc->drl_prob0[i], 1);
+    }
+
+    for (i = 0; i < DRL_MODE_CONTEXTS; ++i) {
+      cpi->drl_mode_cost1[i][0] = vp10_cost_bit(cm->fc->drl_prob1[i], 0);
+      cpi->drl_mode_cost1[i][1] = vp10_cost_bit(cm->fc->drl_prob1[i], 1);
+    }
 #if CONFIG_EXT_INTER
     cpi->new2mv_mode_cost[0] = vp10_cost_bit(cm->fc->new2mv_prob, 0);
     cpi->new2mv_mode_cost[1] = vp10_cost_bit(cm->fc->new2mv_prob, 1);

vp10/encoder/rdopt.c

@@ -6380,7 +6380,9 @@ void vp10_rd_pick_inter_mode_sb(VP10_COMP *cpi,
         int ref_idx;
         int ref_set = VPXMIN(2, mbmi_ext->ref_mv_count[ref_frame_type] - 2);
 
-        rate2 += vp10_cost_bit(128, 0);
+        uint8_t drl0_ctx =
+            vp10_drl_ctx(mbmi_ext->ref_mv_stack[ref_frame_type], 0);
+        rate2 += cpi->drl_mode_cost0[drl0_ctx][0];
 
         if (this_rd < INT64_MAX) {
           if (RDCOST(x->rdmult, x->rddiv, rate_y + rate_uv, distortion2) <
@@ -6440,9 +6442,13 @@ void vp10_rd_pick_inter_mode_sb(VP10_COMP *cpi,
                                            dummy_filter_cache);
           }
 
-          tmp_rate += vp10_cost_bit(128, 1);
-          if (mbmi_ext->ref_mv_count[ref_frame_type] > 3)
-            tmp_rate += vp10_cost_bit(128, ref_idx);
+          tmp_rate += cpi->drl_mode_cost0[drl0_ctx][1];
+
+          if (mbmi_ext->ref_mv_count[ref_frame_type] > 3) {
+            uint8_t drl1_ctx =
+                vp10_drl_ctx(mbmi_ext->ref_mv_stack[ref_frame_type], 1);
+            tmp_rate += cpi->drl_mode_cost1[drl1_ctx][ref_idx];
+          }
 
           if (tmp_alt_rd < INT64_MAX) {
             if (RDCOST(x->rdmult, x->rddiv,