commit 5d5bd0c726a79dd9888328b9ba76416079eb050d
author Debargha Mukherjee <debargha@google.com> Mon Jan 23 08:37:35 2023 -0800
committer Debargha Mukherjee <debargha@google.com> Mon Jan 23 22:45:59 2023 +0000
tree 0c84fdae5fc5422666b666a9792c6d7df7cbdd06
parent 25c8479cd245613e6b948e28a9dd6bee17e8d600

Correct scaled ref indices in compound motion search

Change-Id: I81621c1730ed1793398274de8ea61b694a5b3e4c

av1/encoder/motion_search_facade.c

diff --git a/av1/encoder/motion_search_facade.c b/av1/encoder/motion_search_facade.c
index 2a2ad2e..d232f27 100644
--- a/av1/encoder/motion_search_facade.c
+++ b/av1/encoder/motion_search_facade.c
@@ -738,7 +738,11 @@
     }
     const int mi_row = xd->mi_row;
     const int mi_col = xd->mi_col;
-    av1_setup_pre_planes(xd, ref_idx, scaled_ref_frame, mi_row, mi_col, NULL,
+    // The index below needs to be 0 instead of ref_idx since we assume the
+    // 0th slot to be used for subsequent searches. Note that the ref_idx
+    // reference buffer has been copied to the 0th slot in the code above.
+    // Now we need to swap the reference frame for the 0th slot.
+    av1_setup_pre_planes(xd, 0, scaled_ref_frame, mi_row, mi_col, NULL,
                          num_planes);
   }
 
@@ -767,9 +771,9 @@
                                   &best_mv.as_fullmv, NULL);
 
   if (scaled_ref_frame) {
-    // Swap back the original buffers for subpel motion search.
+    // Swap back the original buffers for subpel motion search for the 0th slot.
     for (int i = 0; i < num_planes; i++) {
-      xd->plane[i].pre[ref_idx] = backup_yv12[i];
+      xd->plane[i].pre[0] = backup_yv12[i];
     }
   }