commit 872fc3ded88da483e723d5aa0a19993dff191fc7
author John Koleszar <jkoleszar@google.com> Tue Mar 12 14:30:18 2013 -0700
committer John Koleszar <jkoleszar@google.com> Tue Mar 12 14:30:23 2013 -0700
tree b49b9c6b70c081cdea5b1c7d3b8819f25286ac89
parent 49d1425d1949bfee12cb07bd18ed4c32e910541b

disambiguate superframe index in vp9_stop_encode()

If the bool-coded partition naturally ends in a byte that matches the
superframe index marker, it could lead to a parse error. This commit
ensures that if such a marker is seen, it is padded out with an
additional zero byte to disambiguate it.

Change-Id: Id977de05745b6fa9ef08afb71e210a2a3ecca02e

vp9/encoder/vp9_boolhuff.c

diff --git a/vp9/encoder/vp9_boolhuff.c b/vp9/encoder/vp9_boolhuff.c
index a590902..2137421 100644
--- a/vp9/encoder/vp9_boolhuff.c
+++ b/vp9/encoder/vp9_boolhuff.c
@@ -53,6 +53,10 @@
 
   for (i = 0; i < 32; i++)
     encode_bool(br, 0, 128);
+
+  // Ensure there's no ambigous collision with any index marker bytes
+  if ((br->buffer[br->pos - 1] & 0xe0) == 0xc0)
+    br->buffer[br->pos++] = 0;
 }