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  • Mixed MPEG and H264 on the same satellite mux

    From NY@21:1/5 to All on Fri Feb 10 09:42:04 2023
    On terrestrial, a T1 mux only contains SD (or sub-SD) channels, and these
    use the MPEG-1 codec. A T2 mux (PSB3 and, previously, COM7/8) contains HD
    and a few SD, and *both* use the H264 codec.

    On satellite it seems that rules are more relaxed: you can get HD channels
    on an S1 mux and you can get a mixture of SD (MPEG) and HD (H264) in the
    same mux.

    Is there anything in the T1/T2 and S1/S2 standards which stipulates the
    codec to be used and the fact that all channels must use the same mux? Is it just convention that terrestrial has no mixed-codec muxes?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Mark Carver@21:1/5 to All on Fri Feb 10 10:14:43 2023
    On 10/02/2023 09:42, NY wrote:
    On terrestrial, a T1 mux only contains SD (or sub-SD) channels, and
    these use the MPEG-1 codec. A T2 mux (PSB3 and, previously, COM7/8)
    contains HD and a few SD, and *both* use the H264 codec.

    On satellite it seems that rules are more relaxed: you can get HD
    channels on an S1 mux and you can get a mixture of SD (MPEG) and HD
    (H264) in the same mux.

    Is there anything in the T1/T2 and S1/S2 standards which stipulates
    the codec to be used and the fact that all channels must use the same
    mux? Is it just convention that terrestrial has no mixed-codec muxes?

    DVB modulation standards (T/2/S/S2) are agnostic I think regarding the
    coding standards, which are a different layer.

    People forget that DAB+ is a coding and not a modulation layer, which is
    why DAB muxes can (and do) carry a mixture of DAB and DAB+ stations

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Brian Gaff@21:1/5 to Mark Carver on Sat Feb 11 09:52:34 2023
    Yes its just data as far as the transmitter is concerned. As long as the receiver can tell the difference and decode them accordingly of course.
    Looking at my old Pure the other day, there are now very few dab stations
    out there compared with the plus. Do we think eventually, DAB will close all the old format stations down and use plus for everything?
    Brian

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    "Mark Carver" <[email protected]d> wrote in message news:[email protected]...
    On 10/02/2023 09:42, NY wrote:
    On terrestrial, a T1 mux only contains SD (or sub-SD) channels, and these
    use the MPEG-1 codec. A T2 mux (PSB3 and, previously, COM7/8) contains HD
    and a few SD, and *both* use the H264 codec.

    On satellite it seems that rules are more relaxed: you can get HD
    channels on an S1 mux and you can get a mixture of SD (MPEG) and HD
    (H264) in the same mux.

    Is there anything in the T1/T2 and S1/S2 standards which stipulates the
    codec to be used and the fact that all channels must use the same mux? Is
    it just convention that terrestrial has no mixed-codec muxes?

    DVB modulation standards (T/2/S/S2) are agnostic I think regarding the
    coding standards, which are a different layer.

    People forget that DAB+ is a coding and not a modulation layer, which is
    why DAB muxes can (and do) carry a mixture of DAB and DAB+ stations

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Dave W@21:1/5 to All on Sat Feb 11 11:07:05 2023
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    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Mark Carver@21:1/5 to Dave W on Sun Feb 12 13:24:09 2023
    On 11/02/2023 11:07, Dave W wrote:
    On Sat, 11 Feb 2023 09:52:34 -0000, "Brian Gaff"
    <[email protected]> wrote:

    Yes its just data as far as the transmitter is concerned. As long as the
    receiver can tell the difference and decode them accordingly of course.
    Looking at my old Pure the other day, there are now very few dab stations
    out there compared with the plus. Do we think eventually, DAB will close all >> the old format stations down and use plus for everything?
    Brian
    What do you mean "very few"? All BBC channels are still DAB.
    <pedant mode>

    Except for BBC Radio Cumbria, Jersey, and Guernsey.
    All 64 k DAB+ Stereo HE-AAC v1

    </pedant mode>

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Brian Gregory@21:1/5 to Brian Gaff on Mon Feb 13 00:42:03 2023
    On 11/02/2023 09:52, Brian Gaff wrote:
    Do we think eventually, DAB will close all
    the old format stations down and use plus for everything?

    I hope so.
    Though it won't be that great if we just get dozens and dozens of weird,
    each only very slightly different, DAB+ stations all using 32 or even
    24kb/s.

    If the BBC DAB mux could change to DAB+ and keep the same bitrates then
    they could, finally, again say truthfully that DAB is near CD quality.

    --
    Brian Gregory (in England).

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Andy Burns@21:1/5 to Brian Gregory on Mon Feb 13 11:00:46 2023
    Brian Gregory wrote:

    If the BBC DAB mux could change to DAB+

    Previously that would have bothered me, as it would have killed-off my
    Evoke3 at home and my older car radio. Newer car radio is now DAB+ and
    Evoke3 has been retired in favour of internet streaming at home.

    But I presume there's still plenty of non-DAB+ listeners out there?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Mark Carver@21:1/5 to Andy Burns on Mon Feb 13 11:09:34 2023
    On 13/02/2023 11:00, Andy Burns wrote:
    Brian Gregory wrote:

    If the BBC DAB mux could change to DAB+

    Previously that would have bothered me, as it would have killed-off my
    Evoke3 at home and my older car radio.  Newer car radio is now DAB+
    and Evoke3 has been retired in favour of internet streaming at home.

    But I presume there's still plenty of non-DAB+ listeners out there?

    In the words of Patrick Moore; 'we simply don't know !'

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)