[mythtv-users] Vintage TV - a UK Freeivew/Data Channel and MythTV

[John Pilkington]

On 06/01/15 19:07, Paul Harrison wrote:
>
> On 06/01/15 13:21, John Pilkington wrote:
>> On 05/01/15 23:49, Paul Harrison wrote:
>>>
>>>
>>> I assume they are using MHEG to kickstart the streaming similar to what
>>> the BBC iPlayer does.
>>>
>>> There are a couple of settings to enable MHEG and the IC (Interative
>>> Channel) that will need to be turned  on.
>>>
>>> There have been some updates to the MHEG stuff to enable the IC on
>>> Freeview. Don't have time to check right now but can't remember if they
>>> were back ported to fixes or not so you may have better luck with
>>> master.
>>>
>>> Running with -v mheg may give a clue why it's failing in the logs.
>>>
>>> Paul H
>>
>> I just enabled MHEG and IC on my SL6 installation of master-pre-2456
>> (2 Jan) with a PCTV-290e usb tuner.
>>
>> Ch 242 works in LiveTV after several tens of seconds 'taking too long
>> to be allowed to read' and 'enabling buffer optimisations for low
>> bitrate stream'.  544x576 H264 AAC/LATM 2ch
>>
>> Starting a recording from the EIT Programme Guide produced a growing
>> file, but attempting to view it caused an apparent system hang for
>> more tens of seconds; it then started playing happily.
>>
>> Restarting playback while recording caused another apparent hangup and
>> the backend reported problems with previewgen.  The recording
>> continued to grow. The frontend initially reported zero bytes but
>> seems to have caught up after recording finished.
>>
>> It would seem best not to try this yet on a production box.
>>
>> As a followup, my tv offers a small selection of unfamiliar channels
>> via Ch 241, but the associated website appears to offer live streaming
>> of many Freeview channels.
>>
>> John P
>
> Probably what is happening is you are just recording the MHEG stream
> which is just a data stream that contains the MPEG carousel. It's the
> same thing you get when you see "Press Red" for some channels often
> called interactive TV. When you switch to a channel like this or
> playback a recording of it Myth has to wait for the app object to come
> around in the carousel again so it can load it and run it, it's similar
> to the old teletext service when after entering a page number you would
> have to wait for the page to come around again before it would show.
> Once the MHEG app is loaded it must be starting to download/stream the
> actual video/audio streams from the internet which is what Myth then
> starts to play. So this accounts for the delay and the strange behaviour
> you are seeing.
>
> It would be interesting to know if a FreeviewHD PVR can record this
> stream. It it can then there must be an extension to the MHEG spec that
> allows for this so we could if we can get the spec add the same option
> to record these internet streams. Of cause it may not be possible to
> record these streams even using an official FreviewHD PVR.
>
> Paul H.

I got a recording of around 90 MB;  almost all of it is FF padding. 
There are occasional probably 188 byte packets of content, some 
including snippets of text like 'rogues.lst' and 'config.txt'

It clearly doesn't include any video.

John P