Adds a zero check in model_rd function

Avoids divide-by-zero when variance is 0.

Change-Id: I3c7f526979046ff7d17714ce960fe81d6e1442a0

diff --git a/vp9/encoder/vp9_rdopt.c b/vp9/encoder/vp9_rdopt.c
index 1b222429b3bb50799049bd6b93804e2b39f31260..7eff2d04d0c7aec2677e2eaf695ff1a15d0beae4 100644 (file)
--- a/vp9/encoder/vp9_rdopt.c
+++ b/vp9/encoder/vp9_rdopt.c
@@ -1803,7 +1803,10 @@ static void model_rd_from_var_lapndz(int var, int n, int qstep,
   // TODO(debargha): Implement the functions by interpolating from a
   // look-up table
   vp9_clear_system_state();
-  {
+  if (var == 0 || n == 0) {
+    *rate = 0;
+    *dist = 0;
+  } else {
     double D, R;
     double s2 = (double) var / n;
     double s = sqrt(s2);