From d98bd80ed3ac2c7274654247daa7b821e2ed6478 Mon Sep 17 00:00:00 2001
From: David Conrad <lessen42@gmail.com>
Date: Tue, 18 May 2010 21:21:28 +0000
Subject: [PATCH] matroskadec: Ensure time_scale is nonzero, fixes
 divide-by-zero if the file has 0 written

Based on a Chromium patch

Originally committed as revision 23167 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavformat/matroskadec.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
index 556d6b9eb8..4d18d99e15 100644
--- a/libavformat/matroskadec.c
+++ b/libavformat/matroskadec.c
@@ -1154,6 +1154,8 @@ static int matroska_read_header(AVFormatContext *s, AVFormatParameters *ap)
         return -1;
     matroska_execute_seekhead(matroska);
 
+    if (!matroska->time_scale)
+        matroska->time_scale = 1000000;
     if (matroska->duration)
         matroska->ctx->duration = matroska->duration * matroska->time_scale
                                   * 1000 / AV_TIME_BASE;