[mythtv-commits] Ticket #12054: Local commercials confuse CEA-608 caption decoding

[MythTV]

#12054: Local commercials confuse CEA-608 caption decoding
-----------------------------------+----------------------------
 Reporter:  faginbagin <mythtv@…>  |          Owner:  stichnot
     Type:  Bug Report - General   |         Status:  new
 Priority:  minor                  |      Milestone:  0.27.4
Component:  MythTV - Captions      |        Version:  0.27-fixes
 Severity:  medium                 |     Resolution:
 Keywords:                         |  Ticket locked:  0
-----------------------------------+----------------------------

Comment (by stichnot):

 OK, I think I got to the bottom of this.  In #9829 and
 d526385aa4c1466b064e9544cdb663f357007e35, code was added such that the
 first time ATSC caption data is seen, any future SCTE caption data is
 explicitly ignored.  (By the way, this was also thanks to WOW's encoding.)
 This is reasonable when the broadcaster duplicates caption data as both
 ATSC and SCTE, but not good when the broadcaster changes from one to the
 other every so often.

 I attached a patch that lets the decoder go back to SCTE after it sees
 SCTE data 10 times in a row (approximately 10 frames, which I chose
 arbitrarily).  It fixes the Jon Stewart sample.

 Helen, could you try out the patch and check that (1) it works for these
 problematic recordings, and (2) it doesn't break anything else?  It should
 apply to both master and fixes-0.27.

--
Ticket URL: <https://code.mythtv.org/trac/ticket/12054#comment:8>
MythTV <http://www.mythtv.org>
MythTV Media Center