Strange Audio Problem with "some" IPTV channels

[jaddi01]

Hello Guys!

 

It's been a while since I was last active on these forums...didn't need to as DVBViewer was always rock solid!

 

However, I have found an interesting and annoying problem with some IPTV Streams.

 

For the Irish TV channels RTE, RTE they both have AAC audio streams and these work with no issues.  However the Virgin Media 1 - 4 channels, which also have AAC audio do not.  Interestingly the AAC Audio image in the DVBViewer footer only becomes visable when starting with an RTE channel and then switching to a Virgin channel. 

 

All of the audio and video channels work in VLC Player.

 

I have the AAC Wrapper and LAV codecs installed.  I have also tried post-processing with AC3Filter, FFDshow etc...same issues.  No audio on Virign channels in DVBViewer, but all work in VLC Player.

 

 

https://github.com/iptv-org/iptv

https://iptv-org.github.io/iptv/countries/ie.m3u

Edited January 6 by jaddi01

[Griga]

vor 2 Stunden schrieb jaddi01:

For the Irish TV channels RTE, RTE they both have AAC audio streams and these work with no issues.  However the Virgin Media 1 - 4 channels, which also have AAC audio do not. 

 

The streams are buggy. When DVBViewer requests

 

GET /s3/virgin_one/index_7/00054/index_7_09958.aac HTTP/1.1

 

the server response is

 

HTTP/1.1 200 OK
Content-Type: video/MP2T
Content-Length: 143978
Connection: keep-alive

...

 

video/MP2T indicates a transport stream, though it actually is a pure audio elementary stream. The Content-Type should be audio/aac. This is misleading and lets DVBViewer fail, because it assumes a wrong format.

 

Of course there are ways to work around it, e.g. by performing checks in a different order (first for an AAC elementary stream, which will succeed due to the .aac extension, then for a transport stream). Or by regarding the file extension as more significant than the Content-Type in the server response. However, implementing such work-arounds for just one faulty provider is an awkward thing, because other cases may require just the opposite... anyway, I will think about it.

 

 

[gwr]

It works with LAV-Splitter. If it is installed. (32 bit)
To do this, in the channel list editor in the properties of Virgin Media Three, for example, check "play as file".
Then in Settings->Options->Playback Components->DVBViewer Filter: File Types Use ...: *.m3u8 (HLS) -> uncheck-> apply
After that, I get Virgin Media Three with sound.
But that's actually just a stopgap solution. no timeshift, recordings have no sound

 

@Griga was faster

 

 

Edited January 6 by gwr

[jaddi01]

Thanks Griga / Gwr!

 

I understand your reluctance to implement a fix for such a small issue.  But I do appreciate you taking it into consideration. 

 

Gwr - Thanks for the workaround. Yes, the loss of Timeshift is a bit of an issue.

[Griga]

vor 5 Stunden schrieb gwr:

It works with LAV-Splitter. If it is installed. (32 bit)

 

LAV Splitter and VLC are using the FFmepg library, that contains powerful format detection code. It doesn't solely rely on file extensions, Content-Type and similar potential liars, but takes a look into the video/audio data and tries to find characteristical headers  indicating the format. However, this requires to first download a portion of the video/audio data and examine it carefully before playback can be configured and started, which takes time, particularly if the server or internet connection is lagging.

 

DVBViewer rather uses a faster method, in order to accelerate playback start. It works reliably as long as the provider adheres to international standards. In this very case it does not - well, life would be boring if erverybody would stick to the rules, wouldn't it?

 

Avoiding the issue is quite easy. I just have to move two lines of code (the check for a transport stream) a bit down, so it is executed after the check for audio elementary formats. I've just tried. It works. You can have a test version if you want. It requires an existing DVBViewer 7.3.1 installation. I'm still looking for a better solution, though...

 

[jaddi01]

Quote

You can have a test version if you want.

 

Wow, I'd love that!  Thanks Griga!  Yes, I'm also on the latest DVBViewer.

[Griga]

Please check your personal forum messages. I've invited you to a conversation where I'm providing a test version with fixes as attachment.

 

[jaddi01]

Test version working perfectly!  Thanks!