Some DVB channels seen as SCTE

[Klaas de Waal]

A channelscan of the DVB-C signal of Ziggo in The Netherlands reports a number of channels as scte channels instead of as dvb channels. This is most likely a bug because the output of mythtv-setup is not correct for these channels. For example, this is the result of the multiplex at 826.75MHz:

qam_256:826750000:24Kitchen:24:5555:1536:20001:2049=2049:dvb	0:cnt(pnum:1,channum:1)
qam_256:826750000:Animal Planet HD:208:5555:1536:20002:2049=2049:dvb	0:cnt(pnum:1,channum:1)
qam_256:826750000:SBS9:19:0-0:20004:0=0=2049:scte	0:cnt(pnum:1,channum:1)
qam_256:826750000:FOX:11:5555:1536:20006:2049=2049:dvb	0:cnt(pnum:1,channum:1)
qam_256:826750000:RTL 4:4:5555:1536:20010:2049=2049:dvb	0:cnt(pnum:1,channum:1)
qam_256:826750000:RTL 5:5:5555:1536:20011:2049=2049:dvb	0:cnt(pnum:1,channum:1)

The first two and the last three channels are shown as dvb channels but the third channel, SBS9, is shown as an scte channel; the channel number 19 is correct but the network ID is shown as 0-0 instead of 5555 and the remainder of the line until the last = does also look wrong.

After a fix in channelscan_sm.cpp the channel SBS9 is correctly shown as a dvb channel:

qam_256:826750000:SBS9:19:5555:1536:20004:2049=2049:dvb	0:cnt(pnum:1,channum:1)

The fix in channelscan_sm.cpp changes the statement "info.is_opencable = true;" to "info.could_be_opencable = true;", as shown here:

        for (uint i = 0; i < descs.size(); ++i)
        {
            RegistrationDescriptor reg(descs[i]);
            if (reg.FormatIdentifierString() == "CUEI" ||
                reg.FormatIdentifierString() == "SCTE")
                info.could_be_opencable = true;           // KdW  was: "info.is_opencable = true;"
        }

The channels that are recognized as scte channels do have an SCTE registration descriptor in the PMT, as verified with the DVB-Inspector analysis tool. However, this should not necessarily make them, as far as I know, into opencable or atsc channels.

Note that the backend can record all channels found, irrespective whether they are identified as scte or as dvb channels.

[Klaas de Waal]

Output of mythtv-setup with the original code, showing some channels as scte instead of dvb.

[Klaas de Waal]

Output of mythtv-setup with the fixed code, showing all channels as dvb.

[Klaas de Waal]

Fix for channelscan_sm.cpp as described now also as a patch.

[Klaas de Waal <klaas.de.waal@…>]

In 3bddcd642/mythtv:

Fixes #13359 - Some DVB Channels seen as SCTE

Signed-off-by: Stuart Auchterlonie <stuarta@…>