commit c23ad632049ff1a61e10250ff61c54d384018a43
author Imdad Sardharwalla <imdad.sardharwalla@argondesign.com> Tue Nov 28 14:12:38 2017 +0000
committer Peter de Rivaz <peter.derivaz@argondesign.com> Wed Dec 20 09:45:46 2017 +0000
tree 73358f44c8a71331aae0cdbc62bd2d42b02fcdfc
parent b260f44fd2ce0bddef0a0f514a089ff87e3381eb

Fix inconsistent use of ref_mv_idx.

"+ 1" has been added in a few locations to match the indices for the
context for the CDFs and the motion vectors.

Suggested fix (of removing +1s entirely) can then be implemented
without further affecting the overall behaviour of the encoder and
decoder.

BUG=aomedia:858

Change-Id: I650a618d3fda1d27bd3550d25ad1ac52e4365061

av1/encoder/bitstream.c

diff --git a/av1/encoder/bitstream.c b/av1/encoder/bitstream.c
index 8afb572..b96a0ca 100644
--- a/av1/encoder/bitstream.c
+++ b/av1/encoder/bitstream.c
@@ -1453,18 +1453,18 @@
       }
     } else if (mode == NEAREST_NEWMV || mode == NEAR_NEWMV) {
       int8_t rf_type = av1_ref_frame_type(mbmi->ref_frame);
-      int nmv_ctx =
-          av1_nmv_ctx(mbmi_ext->ref_mv_count[rf_type],
-                      mbmi_ext->ref_mv_stack[rf_type], 1, mbmi->ref_mv_idx);
+      int nmv_ctx = av1_nmv_ctx(
+          mbmi_ext->ref_mv_count[rf_type], mbmi_ext->ref_mv_stack[rf_type], 1,
+          mbmi->ref_mv_idx + (mode == NEAR_NEWMV ? 1 : 0));
       nmv_context *nmvc = &ec_ctx->nmvc[nmv_ctx];
       av1_encode_mv(cpi, w, &mbmi->mv[1].as_mv,
                     &mbmi_ext->ref_mvs[mbmi->ref_frame[1]][0].as_mv, nmvc,
                     allow_hp);
     } else if (mode == NEW_NEARESTMV || mode == NEW_NEARMV) {
       int8_t rf_type = av1_ref_frame_type(mbmi->ref_frame);
-      int nmv_ctx =
-          av1_nmv_ctx(mbmi_ext->ref_mv_count[rf_type],
-                      mbmi_ext->ref_mv_stack[rf_type], 0, mbmi->ref_mv_idx);
+      int nmv_ctx = av1_nmv_ctx(
+          mbmi_ext->ref_mv_count[rf_type], mbmi_ext->ref_mv_stack[rf_type], 0,
+          mbmi->ref_mv_idx + (mode == NEW_NEARMV ? 1 : 0));
       nmv_context *nmvc = &ec_ctx->nmvc[nmv_ctx];
       av1_encode_mv(cpi, w, &mbmi->mv[0].as_mv,
                     &mbmi_ext->ref_mvs[mbmi->ref_frame[0]][0].as_mv, nmvc,