LiveTv auto subtitle (1 Viewer)

[te3hpurp]

Hi


I noticed small, but a bit annoying thing while switching channels back and forth. Autosubtitles are not allways working.
Kids especially dont like this, calling "Daad!, there is no subtitles", allthough I know there is. I tried to reproduce that and finally
made it happen when switching from "BBC Brit" to "History channel H2". logs contain two attempts to swich from "bbc brit" to "h2".
On first switch both channels show correct subtitle. On a second attempt(ie, swicing ftom "h2" from the first attemtp to "bbc brit") subtitle is also okay.
But on a second tune to "h2" there is no subtitle visible and subtitle context menu has "AUTO:none", but correct finnis subtitle is availabe as last subtitle in list.

I wonder it it's timing issue, or.....

 

[mm1352000]

Hi

I wonder it it's timing issue, or.....

Yep, it seems to be exactly that.

BBC Brit HD has the following sub-streams:
[collapse][2016-04-24 12:00:51,753] [3cca5d8] [6a8] - Recorder: TIMESHIFT add audio stream pid: 0xcb0 fake pid: 0x40 stream type: 0x6 logical type: 0x81 descriptor length: 9
[2016-04-24 12:00:51,753] [3cca5d8] [6a8] - Recorder: TIMESHIFT add subtitle stream pid: 0x19a3 fake pid: 0x50 stream type: 0x6 logical type: 0x6 descriptor length: 10
[2016-04-24 12:00:51,753] [3cca5d8] [6a8] - Recorder: TIMESHIFT add subtitle stream pid: 0x19a5 fake pid: 0x51 stream type: 0x6 logical type: 0x6 descriptor length: 10
[2016-04-24 12:00:51,753] [3cca5d8] [6a8] - Recorder: TIMESHIFT add video stream pid: 0x4db fake pid: 0x30 stream type: 0x1b logical type: 0x1b descriptor length: 0[/collapse]

H2 HD has the following sub-streams:
[collapse][2016-04-24 12:01:28,521] [3cca5d8] [6e4] - Recorder: TIMESHIFT add teletext stream pid: 0x18e3 fake pid: 0x62 stream type: 0x6 logical type: 0x56 descriptor length: 22
[2016-04-24 12:01:28,521] [3cca5d8] [6e4] - Recorder: TIMESHIFT add audio stream pid: 0xd2f fake pid: 0x40 stream type: 0x6 logical type: 0x81 descriptor length: 19
[2016-04-24 12:01:28,521] [3cca5d8] [6e4] - Recorder: TIMESHIFT add video stream pid: 0x525 fake pid: 0x30 stream type: 0x1b logical type: 0x1b descriptor length: 0[/collapse]

From this we can see that the BBC Brit HD subtitles are DVB subtitles, while the H2 HD subtitles are teletext subtitles. The problem only affects teletext subtitles.

If the "OnZapping" occurs before the teletext service information is received ("found preferred subtitle language...") then preferred teletext subtitle selection will be okay. For example:
[2016-04-24 12:01:27,505] [Log ] [MPMain ] [INFO ] - TVHome.ViewChannelAndCheck(): View channel=H2 HD
...
[2016-04-24 12:01:27,676] [Log ] [MPMain ] [INFO ] - TSReaderPlayer: OnZapping :128
...
[2016-04-24 12:01:29,141] [Log ] [MPMain ] [INFO ] - TSReaderPlayer: OnZapping :3
...
[2016-04-24 12:01:29,241] [Log ] [10 ] [DEBUG] - Page 691 is of type 2 and in lang swe
[2016-04-24 12:01:29,242] [Log ] [10 ] [DEBUG] - Page 692 is of type 2 and in lang nor
[2016-04-24 12:01:29,243] [Log ] [10 ] [DEBUG] - Page 693 is of type 2 and in lang dan
[2016-04-24 12:01:29,243] [Log ] [10 ] [DEBUG] - Page 694 is of type 2 and in lang fin
[2016-04-24 12:01:29,243] [Log ] [10 ] [DEBUG] - Found preferred subtitle language fin on page 694 with index 0
...
[2016-04-24 12:01:31,652] [Log ] [10 ] [DEBUG] - Has 5 options
[2016-04-24 12:01:31,653] [Log ] [10 ] [DEBUG] - Teletext Lang swe page : 691 Pref index -1
[2016-04-24 12:01:31,654] [Log ] [10 ] [DEBUG] - Teletext Lang nor page : 692 Pref index -1
[2016-04-24 12:01:31,654] [Log ] [10 ] [DEBUG] - Teletext Lang dan page : 693 Pref index -1
[2016-04-24 12:01:31,654] [Log ] [10 ] [DEBUG] - Teletext Lang fin page : 694 Pref index 0
[2016-04-24 12:01:31,655] [Log ] [10 ] [DEBUG] - Setting as pref

If the "OnZapping" occurs after the teletext service information is received then preferred teletext subtitle selection will fail (...unless the preferred subtitles are provided on page 999). For example:
[2016-04-24 12:02:00,955] [Log ] [MPMain ] [INFO ] - TVHome.ViewChannelAndCheck(): View channel=H2 HD
...
[2016-04-24 12:02:01,055] [Log ] [MPMain ] [INFO ] - TSReaderPlayer: OnZapping :128
...
[2016-04-24 12:02:02,445] [Log ] [10 ] [DEBUG] - Page 691 is of type 2 and in lang swe
[2016-04-24 12:02:02,446] [Log ] [10 ] [DEBUG] - Page 692 is of type 2 and in lang nor
[2016-04-24 12:02:02,446] [Log ] [10 ] [DEBUG] - Page 693 is of type 2 and in lang dan
[2016-04-24 12:02:02,447] [Log ] [10 ] [DEBUG] - Page 694 is of type 2 and in lang fin
[2016-04-24 12:02:02,447] [Log ] [10 ] [DEBUG] - Found preferred subtitle language fin on page 694 with index 0
[2016-04-24 12:02:02,451] [Log ] [MPMain ] [INFO ] - TSReaderPlayer: OnZapping :3

 

[te3hpurp]

Thanks!!

I'll try to see i'm able to create some sort of notification mecanism into my branch that I use to build new Mp versions with tbs CI support, to delay parsing teletext subtitles until OnZapping is done.

Or some other solution.

Br,

 

[mm1352000]

I'll try to see i'm able to ... delay parsing teletext subtitles until OnZapping is done.

I don't think it will be easy.

Another way of explaining the problem is that it only occurs when the teletext service information is received before both video and audio have been received. Order of TS packet reception entirely depends on the broadcast encoder/multiplexer...

 

[te3hpurp]

I'll try to see i'm able to ... delay parsing teletext subtitles until OnZapping is done.

I don't think it will be easy.

Another way of explaining the problem is that it only occurs when the teletext service information is received before both video and audio have been received. Order of TS packet reception entirely depends on the broadcast encoder/multiplexer...

Thanks a lot.

Need to think a bit that.

Br,