[mythtv] [mythtv-commits] Ticket #3326: Implement multiple recordings per transport

[Mark Paulus]

Stuart Morgan wrote:
> On Wednesday 16 January 2008 12:50:34 kmand wrote:
>> My understanding that this refers only to the DVB based satellite
>> multiplexes, and not the HDHomerun.
> 
> DVB-C (Cable), DVB-T (Terrestrial) and ATSC too. ATSC being the North American 
> version of DVB, used for terrestrial only?
> 
> Not sure about support for North American cable, since I don't know what 
> standard that uses, direct mpeg2 streams? (QAM is the wire transmission 
> standard not the data format and should not be likened direct to DVB/ATSC 
> which also both use QAM).
> 
> Can't answer your second question.

I'll add what I have seen, just for info sake.
I have an Air2PC card which I can use to capture free OTA ATSC
traffic.  I get about 8 channels, from 4 or 5 multiplexes.  These
seem to get captured as MPEG TS streams.

I also have an Avermedia A180 and an Dvico pcHDTV RT 5 Lite, 
which are connected to my comcast cable, and talk QAM-256.
I have access to about 40 unencrypted channels, spread across about
a dozen Multiplexes.  One of the multiplexes has 10 unencrypted channels.
This too is captured as MPEG TS.

With my current setup, I am able to do the following for diagnostics
and determination:

I can open 2 windows on my linux box: 1 runs 
'azap -c <conf file> -a <adapter> <mplexid>'.  
I have 3 adapters, and my conf_file is setup to directly
correspond to the results of dtv_multiplex table.
The 2nd window I run 'dvbstream -c <adapter> 8192', 
which sends out a udp stream to 224.0.1.2, on port 1234.
This honks my network by overflowing it, but I only do
it for diagnostics.

My myth boxen are in the basement.  Upstairs, I have a windows
box with TSReader.  I can bring up TSReader and open a 
multicast UDP stream to 224.0.1.2 / 1234, and walla, TSReader
will break out the TS Stream and show me thumbnail stills 
for each unencrypted channel, with it's serviceid.
I have configured TSReader to use vlc, and I can double-click
on a thumbnail, and watch LiveTV from the multiplex via vlc
on the upstairs pc.

One thing I noticed about this, was that I am using a 
Gigabyte GA-K8NSC-939 Mobo upstairs and downstairs, with 
onboard gigabit ethernet.  When I had a MoBo problem
and switched out the basement machine with an MSI Neo4
board, the streaming stuff quit working.  When I put the 
Gigabyte MoBo back, the streaming stuff worked again.  So,
I would say that maybe my setup isn't typical, or YMMV, but
I would think that perhaps what comes out of the HDHomeRun
shouldn't be so different, unless the HDHomeRun is doing the 
TS ==> PS/PES demuxing.  I will say that the full TS stream
coming across my local LAN seems to clog it pretty badly, such
that I can't poll email, or do much other internet stuff 
while the TS is streaming.  So, that makes me think that unless
the HDHomeRun is on a dedicated Loop, it's not sending the
full TS stream for a given multiplex.

Just my observations based upon what I can do with my
equipment.

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