Em Fri, 28 Nov 2014 22:23:13 -0500 Devin Heitmueller <dheitmueller@xxxxxxxxxxxxxx> escreveu: > > I realize captions is an application-layer function, and intend to work with > > the CCExtractor team. Do any other applications already have ISDB caption > > support? I never actually checked how CC works on ISDB-T. On the MPEG-TS tables I worked so far, ISDB-T is very close to DVB, so I would expect that CC would also be close to the DVB descriptors for it, but, as I said, I never actually read that part of the ARIB/ABNT specs. > Based on a Google search, it looks like dvbviewer can decode them: > > http://www.dvbviewer.tv/forum/topic/41933-brazilian-terrestrial-isdb-tb-subtitles-closed-caption/ > http://www.dvbviewer.com/en/index.php > > It's not open source, and it's not Linux, but at least it may give you > something to compare against if you want to build the functionality > yourself. > > > For DVB and ATSC there's quite a bit of code written by several people for > > teletext and captions -- has anything at all been done for ISDB captions? > > Not to my knowledge. I've done a ton of work with CC decoding in VLC, > but haven't poked around at the other formats. > > > It's used in nearly all of Central and South America, plus the Philippines > > and of course Japan -- you would have thought someone has started on the > > task? > > From what I understand, most terrestrial TV in Japan is encrypted, so > you're likely to not find many open source solutions which targeted at > that market. Presumably there is less of that in Brazil (why else > would Mauro be doing all that ISDB-T work if there was no way to watch > the actual video?). > > > We're looking for a good solution for capturing television in Brazil, when > > the signal is encrypted -- are there set-top boxes or tv capture cards that > > handle the decryption so that the decoded signal is passed on with the > > ISDB-Tb caption stream intact? I'm not aware of any device that handles encryption in Brazil. Cryptography is used only in Japan standard, as far as I know. All channels here are in clear, at least for video/audio streams, but, as I said, I never tried to work with CC for ISDB-T. Yet, I would find really weird if just CC is encrypted. > > This would be very unusual. Satellite captioning often has the same > issues - the decoders only support overlaying the captions over the > video and provide no means to access the underlying data. > > Devin > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
