Opened 14 years ago

Closed 11 years ago

#3546 closed defect (wontfix)

MythTV doesn't support mixed sistandards

Reported by: anonymous Owned by: danielk
Priority: trivial Milestone: unknown
Component: MythTV - ATSC Version: head
Severity: low Keywords:
Cc: Ticket locked: no


When performing a fresh channel scan using Hdhomerun, a couple of channels which the hdconfig_gui receives, is not received by the myth scan code. Additionally, when adding the necessary data points to the channel table, myth is still unable to tune the channel. I'm not sure if this should be a new ticket or a reopen of 3305.

The scanning and tuning behavior described above is happening in the .20 fixes branch as well as the trunk.

A case in point is this channel as represented from the hdhomerun_config scan. The second program is the one which fails to be tuned:

SCANNING: 711000000 (us-cable:110, us-irc:110) LOCK: qam256 (ss=97 snq=100 seq=100) PROGRAM: 1: 57.1 WPSG-DT PROGRAM: 2: 0.0

After I tweaked the channel table and manually inserted the frequency and serviceid info, when mythbackend tries to record using program 2, it displays the following errors in the log:

2007-06-02 14:48:29.269 Could not find channel 110_2 in CVCT 2007-06-02 14:48:29.280 VCT Cable: channels(1) tsid(0x8145) seclength(45) Channel #0 name(WPSG-DT) 57-1 mod(SCTE mode 2) cTSID(0x8145)

pnum(1) ETM_loc(0) access_ctrl(0) hidden(0)

path_select(0) out_of_band(0) hide_guide(1) service_type(2) source_id(196)

Change History (6)

comment:1 Changed 14 years ago by danielk

Owner: changed from Isaac Richards to danielk
Priority: minortrivial
Severity: mediumlow
Version: unknownhead

MythTV doesn't support a mix of ATSC and non-ATSC channels on the same transport. You can probably get this to work by creating a duplicate dtv_multiplex row (but with a different mplexid) and using that for the second channel.

This counts as a defect and I've long thought about fixing it, but it's pretty low priority since you are the first person to even report running into this defect in situ.

comment:2 Changed 14 years ago by danielk

Summary: Hdhomerun channel scan missing a few subchannelsMythTV doesn't support mixed sistandards

Just in case someone runs into this ticket in the future let me add to the last comment. After creating the duplicate row the sistandard would need to be set to 'mpeg' for the 0.0 channel's version, and the serviceid in the channel row for the 0.0 channel would need to be set to the MPEG program number. The sistandard of the original dtv_multiplex row would remain 'atsc'.

Also the channel scan is not the problem, the scan is doing what it must to create only tunable channels which are consistent with the MythTV DB schema, the above hack is a work-around and not the correct solution to the problem. The correct solution is to put the sistandard column in the channel table instead of the dtv_multiplex table (it will be added in addition to that column though, for backward compatibility).

comment:3 Changed 14 years ago by Derek Atkins <warlord@…>

Hmm, I wonder if this is related to my HDHomeRun issue where the scan turns up no channels at all. ALL of my channels look like:

SCANNING: 657000000 (us-cable:101, us-irc:101) LOCK: qam256 (ss=89 snq=90 seq=100) PROGRAM: 3: 0.0 PROGRAM: 7: 0.0

Could the "0.0" be why Myth doesn't like my HDHR?

comment:4 Changed 13 years ago by Dibblah

Status: newassigned

comment:5 Changed 12 years ago by stuartm

Component: mythtvMythTV - ATSC

comment:6 Changed 11 years ago by danielk

Resolution: wontfix
Status: assignedclosed

This problem is rare and there is a viable workaround, marking as wontfix.

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