Incorrect program duration

**Peter** · 01-30-2017, 09:46 AM

Hi,
we recently encountered a similar problem using using merged vob files, sometimes the timestamps are restarted in one of the vob files and this results in the incorrect duration being detected. So for vob 1 and 2 the duration is correct but in vob 3 the timestamps restart and when ffmpeg tries to get the duration it reads the last packet from the stream to get the timestamp and subtracts the timestamp in the first packet to get the duration. This can result in a rollover if the last timestamp is very large and result in a value like 10 hours or if the value is very small it can show 5 minutes, either way it is wrong. I suspect that when recording the stream the timestamps may be reset at some point and this is causing the problem, re-encoding the file will correct the timestamps. We made a change in Mezzmo 5.1 for multi-file DVDs to fix the timestamps on the fly when streaming, if you can send us one of the files with the bad timestamps we can possibly do the same procedure when streaming the file. Please upload a sample file to a sharing site like dropbox or google drive and send us a download link to support [at] conceiva [dot] com

**paul49** · 01-31-2017, 08:25 AM

Hi Peter,

Thanks for the response. I suspected a timestamp issue which was perhaps a result of the occasionally poor signal quality of the channel in question. I haven't been using MediaPortal to record TV for very long - perhaps it disturbs/resets the timestamps when a significant loss of signal occurs. Previously I was using WMC but, since I always ran every recording through VideoRedo before it was offered to Mezzmo, I have no idea if the issue occurred in that environment as well.

The only curious thing is that ffmpeg is reporting slightly more than 10 hours for all the corrupt files. I might have expected a more random spread of (incorrectly calculated) durations.

As I said, it's no more than a curiosity. If it becomes an annoyance, I'll just write some code to fix it.