Closed Captions
Closed Captions
The current version of MakeMKV will not allow one to download "Closed Captions"...It appears that you are limited to download/copy "Subtitles" only....Is there a work around for this...Or will this be brought into the fire with next update of MakeMKV?...
Re: Closed Captions
Matroska currently doesn't allow for a 608 caption codec, although that doesn't mean MakeMKV can't invent a method.
The iTunes/Final Cut method may be a good example to follow but currently the decoding support for 608 captions seems borked.
I spent a week with an iTunes m4v and google and apparently that makes me the ripping scenes expert on 608 captions.
Subtitle Edit is currently pretty much useless at decoding 608 and it's method for writing them is based on ignorance. I don't know what the hell CCExtractor is doing, they've either jumped on board this 60 characters a second theory (that really is a dumbass interpretation of 608 bandwidth) or they're adjusting the time-codes for whatever reason suits them. VLCs implementation of 608 is also borked, apparently they're going to have to rewrite the thing to get iTunes files to play properly.
I've informed the Subtitle Edit developers of how captions are supposed to be interpreted and I believe they're working on it. I'm not sure what's happening with VLC at the moment, they went quiet after I showed them an example of 608 captions and it's decoding and have simply reactivated the ticket I was posting on and switched it from a Demuxer problem to a Decoder problem. I don't know if it's going to get fixed any time soon.
Basically, understanding of 608 captions seems to be non-existent in our circles, I haven't asked but I'm pretty sure the MakeMKV team have no idea how the bloody things work, so expecting them to figure out how to add them to a file is a pretty big ask at this stage.
The iTunes/Final Cut method may be a good example to follow but currently the decoding support for 608 captions seems borked.
I spent a week with an iTunes m4v and google and apparently that makes me the ripping scenes expert on 608 captions.
Subtitle Edit is currently pretty much useless at decoding 608 and it's method for writing them is based on ignorance. I don't know what the hell CCExtractor is doing, they've either jumped on board this 60 characters a second theory (that really is a dumbass interpretation of 608 bandwidth) or they're adjusting the time-codes for whatever reason suits them. VLCs implementation of 608 is also borked, apparently they're going to have to rewrite the thing to get iTunes files to play properly.
I've informed the Subtitle Edit developers of how captions are supposed to be interpreted and I believe they're working on it. I'm not sure what's happening with VLC at the moment, they went quiet after I showed them an example of 608 captions and it's decoding and have simply reactivated the ticket I was posting on and switched it from a Demuxer problem to a Decoder problem. I don't know if it's going to get fixed any time soon.
Basically, understanding of 608 captions seems to be non-existent in our circles, I haven't asked but I'm pretty sure the MakeMKV team have no idea how the bloody things work, so expecting them to figure out how to add them to a file is a pretty big ask at this stage.
Re: Closed Captions
OK, let's see...
In the case of iTunes captions Subtitle Edit can't read them properly yet, VLC can't read them properly yet, I just got confirmation that CCExtractor doesn't read them properly either.
FFMPEG can't read them and neither can MPC-HC.
Handbrake can't make them, can't even pass them through to another mp4 apparently.
I haven't tried LAV FFMPEG yet.
I THINK most of them can decode Captions from a DVD to some extent, I haven't tested it properly though. It depends on if someone actually had some specs at some point or if they just made the decoding process up based on what they found in files. Anyway, I'm pretty sure figuring out the timings for 30000/1001 fps video would be easy enough, but I'm not sure how 24000/1001 timings are being determined. It may be an insignificant difference but if there's 30 frames worth of data contained within only 24 actual frames then the data still needs to be distributed in the timeline at two bytes per frame at 30fps as if they were being written into line 21 which is how they're designed to be, if they don't do that then it's not technically correct.
The main problem is that one "stream" of captions contains 4(2x2) "subtitle tracks" plus a bunch of other metadata, you'll be unlikely to find the other metadata on a DVD but any proper implementation of 608 captions would have to include the possibility of their existence.
Based on what happened to TrueHD, Matroska is only supposed to hold ONE track per stream and I don't see any way of adding the captions to an MKV short of separating them in to individual components and adding headers for each set of data. But of course 608 captions are designed to be written into line 21, so any player capable of reading them SHOULD be able to recreate the original 608 stream so that it can write the captions back into Line 21, which can't be guaranteed if you split the things up.
Basically, it gets complicated...
In the case of iTunes captions Subtitle Edit can't read them properly yet, VLC can't read them properly yet, I just got confirmation that CCExtractor doesn't read them properly either.
FFMPEG can't read them and neither can MPC-HC.
Handbrake can't make them, can't even pass them through to another mp4 apparently.
I haven't tried LAV FFMPEG yet.
I THINK most of them can decode Captions from a DVD to some extent, I haven't tested it properly though. It depends on if someone actually had some specs at some point or if they just made the decoding process up based on what they found in files. Anyway, I'm pretty sure figuring out the timings for 30000/1001 fps video would be easy enough, but I'm not sure how 24000/1001 timings are being determined. It may be an insignificant difference but if there's 30 frames worth of data contained within only 24 actual frames then the data still needs to be distributed in the timeline at two bytes per frame at 30fps as if they were being written into line 21 which is how they're designed to be, if they don't do that then it's not technically correct.
The main problem is that one "stream" of captions contains 4(2x2) "subtitle tracks" plus a bunch of other metadata, you'll be unlikely to find the other metadata on a DVD but any proper implementation of 608 captions would have to include the possibility of their existence.
Based on what happened to TrueHD, Matroska is only supposed to hold ONE track per stream and I don't see any way of adding the captions to an MKV short of separating them in to individual components and adding headers for each set of data. But of course 608 captions are designed to be written into line 21, so any player capable of reading them SHOULD be able to recreate the original 608 stream so that it can write the captions back into Line 21, which can't be guaranteed if you split the things up.
Basically, it gets complicated...