[mythtv] [mythtv-commits] Ticket #13292: LiveTV Channel Switching - DVB-T/T2 UK Freeview

[Mike Bibbings]

On 07/06/18 14:01, John Pilkington wrote:
> On 07/06/18 08:42, MythTV wrote:
>> #13292: LiveTV Channel Switching - DVB-T/T2 UK Freeview
>> ----------------------------------+------------------------------
>>   Reporter:  Mike Bibbings         |          Owner:  (none)
>>       Type:  Bug Report - General  |         Status:  new
>>   Priority:  minor                 |      Milestone: needs_triage
>> Component:  MythTV - DVB          |        Version:  Master Head
>>   Severity:  medium                |     Resolution:
>>   Keywords:                        |  Ticket locked:  0
>> ----------------------------------+------------------------------
>>
>> Comment (by Mike Bibbings):
>>
>>   transport dumps for skynews, single channel and full mux are 
>> available at
>> https://www.dropbox.com/sh/0n0t3ebp4nwiy3g/AACeC4WijoHLzj6Mrq1pgdmDa?dl=0
>>
>
> I'm getting read-only access to Trac at present.
>
> I don't use 'live' much, but viewing SkyNews does seem to have 
> hang-ups.  Entering via 'Watch this channel,' it often works for me, 
> but sometimes no sound: quit by ^C.
>
> {{{
> 2018-06-07 13:43:18.924803 N  Player(0): Waited 1396ms for video 
> buffers uLLAAAAAAAAAAAAAAAAAAAAAAAAAAAAP
> 2018-06-07 13:43:19.032085 N  Player(0): Waited 1503ms for video 
> buffers uLLAAAAAAAAAAAAAAAAAAAAAAAAAAAAP
> 2018-06-07 13:43:19.139402 N  Player(0): Waited 1611ms for video 
> buffers uLLAAAAAAAAAAAAAAAAAAAAAAAAAAAAP
> 2018-06-07 13:43:19.246688 N  Player(0): Waited 1718ms for video 
> buffers uLLAAAAAAAAAAAAAAAAAAAAAAAAAAAAP
> 2018-06-07 13:43:19.345546 W  AFD: Audio 56200113 ms behind video but 
> already 220 video frames queued. AV-Sync might be broken.
> 2018-06-07 13:43:19.346439 W  AFD: Audio 56200153 ms behind video but 
> already 220 video frames queued. AV-Sync might be broken.
> 2018-06-07 13:43:19.347502 W  AFD: Audio 56200193 ms behind video but 
> already 220 video frames queued. AV-Sync might be broken.
> 2018-06-07 13:43:19.353942 N  Player(0): Waited 1825ms for video 
> buffers UuUULLAAAAAAAAAAAAAAAAAAAAAAAAAP
> 2018-06-07 13:43:19.461140 N  Player(0): Waited 1933ms for video 
> buffers UuUULLAAAAAAAAAAAAAAAAAAAAAAAAAP
> }}}
>
> and sometimes the Decoder fails.  That's master-pre-ff4.  Doesn't seem 
> much different with ff4.
>
> And playing a radio channel (I think the ^C probably stopped the 
> expected channel update) needed another ^C to quit.
> _______________________________________________ 


I have done some more investigation and traced the problem to audio 
stream detection and have updated trac ticket with my findings.

With a debug patch applied channel switching is ok and much faster. 
Stream detection now happens  in a few 100 ms, and no longer defaults to 
in-file.

Mike