The VideoLAN Forums

Greetings:

I have a windows / Mac / iOS Device household. We have a range of media in various formats, however it is WTV that is causing grief. More specifically the video is jittery (its like it forgets every 3 frames out of 4)... kinda like slow motion playback - however the audio is fine. But as I've been troubleshooting, I've stumbled upon a variant that makes this problem very interesting.

Firstly:
- I initially thought the network was at fault, however I copied various files to my local MAC (VLC 2.1.1 Ricewind) and the same problem manifests
- If I run a windows virtual machine (via Fusion) on my Mac and use windows media player to playback the WTV file - either locally or from any of the other PC's (or NAS) in the house - it works fine.
- I tried VLC iOS and the same problem.
- I installed VLC 2.1.1 in my Windows virtual machine - it works FINE (either with local or network source)
- if I open any other source (eg: ripped DVD (mpeg2), MKV, etc) - they all work fine

But here's the weird variant:
- Being in Australia, we have a variety of free-to-air television stations.
- The problem ONLY manifests with WTV files recorded from channel 2.
- If I open content recorded from other channels, say 7 or 9, it works fine

So to summarise:
- the problem manifests with iOS / Mac VLC using WTV files from channel 2 only
- the problem DOES NOT manifest using Windows VLC

I'm using Windows 7 media centre to do all the recording.

Please share the file that has the issue.
Seriously.

Um, seriously, they are all over 12GB. I'll record some smaller segments and post accordingly.

I'm still trying to solve this problem, I haven't found a way of uploading the large file, but perhaps what I have found removes VLC from the list of suspects.

I tried to re-encode a smaller (1.3GB) WTV file to MP4 using handbrake. The WTV had the same playback issues in VLC
The resulting MP4 had exactly the same symptoms. During the conversion process, I noticed the following in the logs

[09:42:30] sync: video time didn't advance - dropped 7 frames (delta 2080 ms, current 169927479, next 169937952, dur 10473)
[09:42:30] sync: video time didn't advance - dropped 1 frames (delta 247 ms, current 169958897, next 169969370, dur 10473)
[09:42:30] sync: video time didn't advance - dropped 7 frames (delta 2080 ms, current 169970679, next 169981152, dur 10473)
[09:42:30] sync: video time didn't advance - dropped 1 frames (delta 247 ms, current 170002097, next 170012570, dur 10473)
[09:42:30] sync: video time didn't advance - dropped 7 frames (delta 2080 ms, current 170013879, next 170024352, dur 10473)
[09:42:30] sync: video time didn't advance - dropped 1 frames (delta 247 ms, current 170045297, next 170055770, dur 10473)
[09:42:30] sync: video time didn't advance - dropped 7 frames (delta 2080 ms, current 170057079, next 170067552, dur 10473)
[09:42:30] sync: video time didn't advance - dropped 1 frames (delta 247 ms, current 170088497, next 170098970, dur 10473)
[09:42:30] sync: video time didn't advance - dropped 7 frames (delta 2080 ms, current 170100279, next 170110752, dur 10473)
....
[09:42:44] sync: got 18262 frames, 53112 expected

I'm still researching, if I find more info, I'll report it. I'd like to find out if VLC/Handbrake share any of the same underlying tools.

they do.