diff --git a/libavcodec/aacps.c b/libavcodec/aacps.c
index 1165d9be3f..ccc79ffc1d 100644
--- a/libavcodec/aacps.c
+++ b/libavcodec/aacps.c
@@ -940,7 +940,7 @@ static void stereo_processing(PSContext *ps, INTFLOAT (*l)[32][2], INTFLOAT (*r)
             LOCAL_ALIGNED_16(INTFLOAT, h_step, [2], [4]);
             int start = ps->border_position[e];
             int stop  = ps->border_position[e+1];
-            INTFLOAT width = Q30(1.f) / (stop - start);
+            INTFLOAT width = Q30(1.f) / ((stop - start) ? (stop - start) : 1);
 #if USE_FIXED
             width <<= 1;
 #endif