Caption export into new container

atc98092

New member
My understanding is that VRD will only save captions contained in a WTV video back into the same container. Since none of my playback devices support WTV, and one of my players does not support MPEG2 video, I need to use convert the video and use another container. MKV seems to be the most universally accepted container for videos with multiple tracks, this seems to be the most logical one to use. Of course, MP4 would also be usable. So, I would suggest that captions be exported into containers other than WTV.

The second part of this is that broadcast television captions are almost always in EIA-608 format. Again, this caption cannot be read from anything but the WTV container with the usual players. VLC works fine on a computer, but I am using either a Roku, Blu-Ray player or Smart TV for my playback. Therefore, the captions need to be converted. One method is to convert them from the WTV file. This won't work however, since the time codes will be out of sync as soon as the file is edited (removing commercials). So the captions need to be converted after editing.

I suggest one of two methods. Either method will obviously add more time to the file save after the edits, but that should be an acceptable tradeoff for the user to determine. Method one: make a quick save of the edited file back into the WTV container. This can be accomplished quite quickly (I usually see 4 minutes or less for a 2 hour edited movie). After this is complete, run a conversion of the EIA captions into an SRT file. Finally, merge the SRT file into a completed MKV/MP4 file. I realize I could do this myself one step at a time, but I'd rather see the process automated once the conversion begins.

The second method is more complicated, but might be overall faster. This would be to convert the EIA caption during the video conversion, all in one process. While I have done a fair amount of computer programming, I know extremely little about video processing. I have no idea what sort of work this might entail, and what sort of computer hardware might be required.

I'm unfamiliar with the various caption formats. I know VobSub (used on DVDs) works with all my devices. My Samsung JU7100 appears to support something called SubStation Alpha, Advanced SubStation Alpha and SubRip in the MKV container. Other than them being labeled as text formats, I know nothing about them.

I understand that what I am suggesting may be beyond the potential of the computers/software we currently use. I just offer this as a possible feature that might be welcomed by users that record OTA TV and convert to other formats. Sometimes it just takes a suggestion for a programmer to think of a solution. I know on several programs I wrote that some improvements would never have happened without someone saying "Hey, can you make it do this?"

If I'm wrong and there's already a way to convert captions, I'm all ears! :D
 

Danr

Administrator
Staff member
A variety of caption conversion options are being worked on including (hopefully), 608 to SCC, 608 to SRT, 608/708 to a text track for MP4, and finally a 608/708 burn-in option.
 

jmc

Active member
My experience is that it is most compatible to have
external subtitles(.idx) or "Closed Caption"(CC)(.srt) files.

For instance, CC in H264.MP4 files from mpg files.
CC is there but the only program I have had that will display
the CC is VRD itself.
That CC as an external file does display in VLC and MPClassic.

Glad to see that some of this processing will (at some point) be built into VRD!

jmc
 
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atc98092

New member
A variety of caption conversion options are being worked on including (hopefully), 608 to SCC, 608 to SRT, 608/708 to a text track for MP4, and finally a 608/708 burn-in option.
An SRT file would work fine. My DLNA server (Serviio) and my devices all support them. Thanks for the heads up. When beta becomes available to support this, I'll be happy to test it out.
 
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