Playing back of BBC 4 HD with Lav Video Decoders

[robbyp]

Hi,

Version 4.2.2

So If i play back a BBC4 HD file using LAV Video Decoders (0.71) selected for H264 inside NPVR (EVR Renderer), its unstable, crashing, not moving forward, etc.

If I play back a another HD file from another source, it seems well behaved.

If I play back the same BBC4 HD file using VLC player - it plays okay. Its stable.

This seems repeatable.

So,

1. What's the difference between BBC4 HD and other HD streams which is causing the difference?

2. Is there any debug I can turn on to help diagnose the problem?

3. Should I use another set of video decoders?

Thanks

Rob

[sub]

Can you supply a sample recording, so I can try playing it here?

[Petrovski]

BBC4 HD is worst channel for me too. I think it has more errors in stream because it's a lower power multiplex and I am some distance from the Winter Hill transmitter.
I don't know if that is a countrywide thing though.
BTW I have been meaning to post for a while that NPVR hangs sometimes on selecting BBC4HD during daytime (BBC4HD is evenings only) - also if BBC4 HD is the last channel watched then when NPVR is launched during daytime using LiveTV on remote NPVR hangs and has to be closed (sometimes forcefully).
I think this probably occurs on any channel that is not currently transmitting?

[sub]

BBC4 HD is worst channel for me too. I think it has more errors in stream because it's a lower power multiplex and I am some distance from the Winter Hill transmitter.

That would be my guess too. I was hoping to confirm it by looking at a recording.

BTW I have been meaning to post for a while that NPVR hangs sometimes on selecting BBC4HD during daytime (BBC4HD is evenings only) - also if BBC4 HD is the last channel watched then when NPVR is launched during daytime using LiveTV on remote NPVR hangs and has to be closed (sometimes forcefully).

I would suspect some questionable behaviour when you try to watch it when it's off air. Unfortunately we don't have any similar channels here in NZ, with part time transmission, so it's not something I've explicitly been able to test.

[robbyp]

I'll try and capture a short recording tomorrow..

[robbyp]

I have PMed you a link to the google recording showing this behaviour Sub ;-) Many thanks.

[sub]

Thanks. I've downloaded it. As suspected - the file is full of continuity errors, indicating missing packets, and a large percentage of the packets that there have the TEI flag set, indicating those packets contained unrecoverable transmission errors.

The only fix is really to improve your reception.

[sub]

The first 15% of the file had 22000 missing bits (made up of one or more packets), and 105000 packets with errors. So, pretty severely damaged.

[Bobins]

This is likely to be associated with the recent frequency changes affecting BBC4HD and the fact that many users will have group A or B aerials which don't cope well with low power transmissions which are outside the rated frequency band for the aerial.
The only current fix would be an aerial change and/or a signal amplifier. Of course this assumes that the current low signal problem isn't being caused by a damaged aerial/cable or cable splitter.

[robbyp]

So, bbc4 is nearly out of band for me, on 586 MHz, from my previous group E set (Mendip).

So there are two problems - one is my antenna problem.

The second is NPVR/Lame response to this bad data.. i've seen NPVR/Lame crashing with this sort of data. Did you see that behaviour?