From 530a867d51b9bac097286bc5d8947e91cf18d248 Mon Sep 17 00:00:00 2001
From: Robert Kausch <robert.kausch@freac.org>
Date: Mon, 20 Mar 2023 21:42:13 +0100
Subject: [PATCH] Fix division by zero in mp4trackdump.

---
 util/mp4trackdump.cpp | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/util/mp4trackdump.cpp b/util/mp4trackdump.cpp
index 6d35c13..e334d45 100644
--- a/util/mp4trackdump.cpp
+++ b/util/mp4trackdump.cpp
@@ -38,7 +38,7 @@ static void DumpTrack ( MP4FileHandle mp4file, MP4TrackId tid )
     MP4SampleId sid;
     MP4Duration time;
     uint32_t timescale;
-    uint64_t msectime;
+    uint64_t msectime = 0;
 
     uint64_t sectime, mintime, hrtime;
 
@@ -49,9 +49,12 @@ static void DumpTrack ( MP4FileHandle mp4file, MP4TrackId tid )
 
     for ( sid = 1; sid <= numSamples; sid++ ) {
         time = MP4GetSampleTime( mp4file, tid, sid );
-        msectime = time;
-        msectime *= UINT64_C( 1000 );
-        msectime /= timescale;
+        if ( timescale > 0 ) {
+            msectime = time;
+            msectime *= UINT64_C( 1000 );
+            msectime /= timescale;
+        }
+
         if ( msectime == 0 ) {
             hrtime = mintime = sectime = UINT64_C( 0 );
         }