Make mv storage independent of ref frame index

The motion vector storage location in the reference frame is set
to be dependent on the relative frame position, instead of the
reference frame index.

Change-Id: Id8f7d1e6ba32a5ed9e182194178fd2a70094a309

av1/common/mvref_common.c

@@ -34,10 +34,27 @@ void av1_copy_frame_mvs(const AV1_COMMON *const cm, MODE_INFO *mi, int mi_row,
   for (h = 0; h < y_mis; h++) {
     MV_REF *mv = frame_mvs;
     for (w = 0; w < x_mis; w++) {
+#if CONFIG_MFMV
+      mv->ref_frame[0] = NONE_FRAME;
+      mv->ref_frame[1] = NONE_FRAME;
+      mv->mv[0].as_int = 0;
+      mv->mv[1].as_int = 0;
+
+      for (int idx = 0; idx < 2; ++idx) {
+        MV_REFERENCE_FRAME ref_frame = mi->mbmi.ref_frame[idx];
+        if (ref_frame > INTRA_FRAME) {
+          int8_t ref_idx = cm->ref_frame_side[ref_frame];
+          if (ref_idx < 0) continue;
+          mv->ref_frame[ref_idx] = ref_frame;
+          mv->mv[ref_idx].as_int = mi->mbmi.mv[idx].as_int;
+        }
+      }
+#else
       mv->ref_frame[0] = mi->mbmi.ref_frame[0];
       mv->ref_frame[1] = mi->mbmi.ref_frame[1];
       mv->mv[0].as_int = mi->mbmi.mv[0].as_int;
       mv->mv[1].as_int = mi->mbmi.mv[1].as_int;
+#endif
       // (TODO:yunqing) The following 2 lines won't be used and can be removed.
       mv->pred_mv[0].as_int = mi->mbmi.pred_mv[0].as_int;
       mv->pred_mv[1].as_int = mi->mbmi.pred_mv[1].as_int;
@@ -1689,6 +1706,19 @@ void av1_setup_motion_field(AV1_COMMON *cm) {
     alt2_frame_index =
         cm->buffer_pool->frame_bufs[alt2_buf_idx].cur_frame_offset;
 
+  memset(cm->ref_frame_side, 0, sizeof(cm->ref_frame_side));
+  for (int ref_frame = LAST_FRAME; ref_frame < INTER_REFS_PER_FRAME;
+       ++ref_frame) {
+    int buf_idx = cm->frame_refs[ref_frame - LAST_FRAME].idx;
+    int frame_index = -1;
+    if (buf_idx >= 0)
+      frame_index = cm->buffer_pool->frame_bufs[buf_idx].cur_frame_offset;
+    if (frame_index > cur_frame_index)
+      cm->ref_frame_side[ref_frame] = 1;
+    else if (frame_index == cur_frame_index)
+      cm->ref_frame_side[ref_frame] = -1;
+  }
+
   if (alt_frame_index < cur_frame_index) return;
 
   int ref_stamp = MFMV_STACK_SIZE - 1;

av1/common/onyxc_int.h

@@ -577,6 +577,8 @@ typedef struct AV1Common {
 #endif
 #if CONFIG_MFMV
   TPL_MV_REF *tpl_mvs;
+  // TODO(jingning): This can be combined with sign_bias later.
+  int8_t ref_frame_side[TOTAL_REFS_PER_FRAME];
 #endif
 
 #if TXCOEFF_TIMER