commit f178329191f668aeb78ed63f2fa02c1bb21b8ac3
author Sarah Parker <sarahparker@google.com> Wed Apr 05 11:55:27 2017 -0700
committer Debargha Mukherjee <debargha@google.com> Fri Apr 07 22:39:42 2017 +0000
tree f2cbb8f05fb858e1b7835699ee35bc2c9bc83c87
parent 9d53302c3682d0372b7f1e24b11539b444727dc5

Add gm parameter coding based on ref parameters

Change-Id: Ic2344a6475b967fa07f70b3ffad2714de657bb49

av1/encoder/bitstream.c

diff --git a/av1/encoder/bitstream.c b/av1/encoder/bitstream.c
index 382d5cc..8ebbedc 100644
--- a/av1/encoder/bitstream.c
+++ b/av1/encoder/bitstream.c
@@ -4598,6 +4598,7 @@
 
 #if CONFIG_GLOBAL_MOTION
 static void write_global_motion_params(WarpedMotionParams *params,
+                                       WarpedMotionParams *ref_params,
                                        aom_prob *probs, aom_writer *w,
                                        int allow_hp) {
   TransformationType type = params->wmtype;
@@ -4610,31 +4611,40 @@
     case HORTRAPEZOID:
     case VERTRAPEZOID:
       if (type != HORTRAPEZOID)
-        aom_write_primitive_symmetric(
-            w, (params->wmmat[6] >> GM_ROW3HOMO_PREC_DIFF),
-            GM_ABS_ROW3HOMO_BITS);
+        aom_write_signed_primitive_refsubexpfin(
+            w, GM_ROW3HOMO_MAX + 1, SUBEXPFIN_K,
+            (ref_params->wmmat[6] >> GM_ROW3HOMO_PREC_DIFF),
+            (params->wmmat[6] >> GM_ROW3HOMO_PREC_DIFF));
       if (type != VERTRAPEZOID)
-        aom_write_primitive_symmetric(
-            w, (params->wmmat[7] >> GM_ROW3HOMO_PREC_DIFF),
-            GM_ABS_ROW3HOMO_BITS);
+        aom_write_signed_primitive_refsubexpfin(
+            w, GM_ROW3HOMO_MAX + 1, SUBEXPFIN_K,
+            (ref_params->wmmat[7] >> GM_ROW3HOMO_PREC_DIFF),
+            (params->wmmat[7] >> GM_ROW3HOMO_PREC_DIFF));
     // fallthrough intended
     case AFFINE:
     case ROTZOOM:
-      aom_write_primitive_symmetric(
-          w,
-          (params->wmmat[2] >> GM_ALPHA_PREC_DIFF) - (1 << GM_ALPHA_PREC_BITS),
-          GM_ABS_ALPHA_BITS);
+      aom_write_signed_primitive_refsubexpfin(
+          w, GM_ALPHA_MAX + 1, SUBEXPFIN_K,
+          (ref_params->wmmat[2] >> GM_ALPHA_PREC_DIFF) -
+              (1 << GM_ALPHA_PREC_BITS),
+          (params->wmmat[2] >> GM_ALPHA_PREC_DIFF) - (1 << GM_ALPHA_PREC_BITS));
       if (type != VERTRAPEZOID)
-        aom_write_primitive_symmetric(
-            w, (params->wmmat[3] >> GM_ALPHA_PREC_DIFF), GM_ABS_ALPHA_BITS);
+        aom_write_signed_primitive_refsubexpfin(
+            w, GM_ALPHA_MAX + 1, SUBEXPFIN_K,
+            (ref_params->wmmat[3] >> GM_ALPHA_PREC_DIFF),
+            (params->wmmat[3] >> GM_ALPHA_PREC_DIFF));
       if (type >= AFFINE) {
         if (type != HORTRAPEZOID)
-          aom_write_primitive_symmetric(
-              w, (params->wmmat[4] >> GM_ALPHA_PREC_DIFF), GM_ABS_ALPHA_BITS);
-        aom_write_primitive_symmetric(w,
-                                      (params->wmmat[5] >> GM_ALPHA_PREC_DIFF) -
-                                          (1 << GM_ALPHA_PREC_BITS),
-                                      GM_ABS_ALPHA_BITS);
+          aom_write_signed_primitive_refsubexpfin(
+              w, GM_ALPHA_MAX + 1, SUBEXPFIN_K,
+              (ref_params->wmmat[4] >> GM_ALPHA_PREC_DIFF),
+              (params->wmmat[4] >> GM_ALPHA_PREC_DIFF));
+        aom_write_signed_primitive_refsubexpfin(
+            w, GM_ALPHA_MAX + 1, SUBEXPFIN_K,
+            (ref_params->wmmat[5] >> GM_ALPHA_PREC_DIFF) -
+                (1 << GM_ALPHA_PREC_BITS),
+            (params->wmmat[5] >> GM_ALPHA_PREC_DIFF) -
+                (1 << GM_ALPHA_PREC_BITS));
       }
     // fallthrough intended
     case TRANSLATION:
@@ -4643,10 +4653,14 @@
       trans_prec_diff = (type == TRANSLATION)
                             ? GM_TRANS_ONLY_PREC_DIFF + !allow_hp
                             : GM_TRANS_PREC_DIFF;
-      aom_write_primitive_symmetric(w, (params->wmmat[0] >> trans_prec_diff),
-                                    trans_bits);
-      aom_write_primitive_symmetric(w, (params->wmmat[1] >> trans_prec_diff),
-                                    trans_bits);
+      aom_write_signed_primitive_refsubexpfin(
+          w, (1 << trans_bits) + 1, SUBEXPFIN_K,
+          (ref_params->wmmat[0] >> trans_prec_diff),
+          (params->wmmat[0] >> trans_prec_diff));
+      aom_write_signed_primitive_refsubexpfin(
+          w, (1 << trans_bits) + 1, SUBEXPFIN_K,
+          (ref_params->wmmat[1] >> trans_prec_diff),
+          (params->wmmat[1] >> trans_prec_diff));
       break;
     case IDENTITY: break;
     default: assert(0);
@@ -4665,9 +4679,9 @@
       set_default_gmparams(&cm->global_motion[frame]);
     }
 #endif
-    write_global_motion_params(&cm->global_motion[frame],
-                               cm->fc->global_motion_types_prob, w,
-                               cm->allow_high_precision_mv);
+    write_global_motion_params(
+        &cm->global_motion[frame], &cm->prev_frame->global_motion[frame],
+        cm->fc->global_motion_types_prob, w, cm->allow_high_precision_mv);
     /*
     printf("Frame %d/%d: Enc Ref %d (used %d): %d %d %d %d\n",
            cm->current_video_frame, cm->show_frame, frame,