The VideoLAN Forums

I recall from some time ago there was some discussion in the forum somewhere that closed captioning was going to be included in a future version of VLC. I just downloaded VLC 0.7.2 and I cannot find that feature anywhere. It's different from subtitle and something I sorely need to be able to view my tv shows in mpeg format.

Where can I find the feature to turn on captioning?

TIA

It is still not implemented. closed captions pose a problem in that they are encoded in the video stream. This makes them harder to handle...

But to be honest, the information on how closed captioning is supposed to be done is just so sketchy, that it is a bit of a mess. We kinda got lost

We will try again in the future, when our core is more able to handle this.

DJ

Hello,

I work for a company that makes MPEG-2 Encoders and I recently added CC support to our AVN200 product. It is a little hard to find detailed info on, but it is out there we went according to the ATSC standard.

I am curious how far along you are in development, or even interest for that matter in offering CC support in VLC at least for MPEG-2. I would be interested in trying to help if you are already started and stuck or just looking for some geek to pawn it off on. I have not dove into any VLC source yet so I am not sure what I might be signing up for, but it is something that I may want to implement to compliment our software for the AVN200 in the future.

It seems that it would basically consist of extracting the encoding CC data from the Picture Headers in the Video Elmentary Stream Data and passing it somewhere...

the first part is where I think I could be of some help, but how to use the data once retrieved is the tricky part for me.

In my world:
Source->Analog->MPEG->IP------------>Decoder-->Analog-->Display

the end result for the data would be destined for an Analog display output such as a TV or security monitor. In this case the CC data once extracted by the decoder is passed to the DtoA to be encoded onto line 21 of the analog signal for the monitor to again decode and display.

In the world of VLC and VGA output I am not sure how you embed the CC data in the display, but I would hope that you could take advantage of an existing sub-system such as the subtitles functionality to accomplish such a task

ok, i have since then looked into it and even started working on it. However, i'm currently sidetracked into another project (which actually pays ).

The conslusion is that for DVB it's not that hard. I have been looking at EBU teletext myself (ETSI EN 300 472)
What needs to be done:

1: Identify VBI data streams in DVB (libdvbpsi etc)
(done this for EBU teletext in modules/demux/ts.c recently. VBI data and VBI teletext yet to be done)
2: catch these data from the tracks and pass it into a ES with the correct FOURCC (telx for EBU teletext)
3: feed this data into a VBI subtitle decoder (Yet to be done. should look something like a cross of logo.c and freetype.c. VBI decoding can use the ZVBI library to make picture data from the VBI data)

For CC and VBI in analog encoded video, it's harder i guess, but I haven't seen that very much to be honest. In this case you need the decoder to feed you the VBI data, a concept VLC will honest to god not like.

Have you looked at the following availble source for Teletext?

http://www.doom9.org/index.html?/DigiTV/projectx.htm

Sorry, but I posted the wrong link.

http://www.lucike.info/page_projectx.htm

This project does among other things extract Teletext from a
Mpeg-2 stream. The source code is also available, and its
GNU General Public License.

What is the current status for closed captioning implementation? Is anybody working on it? Just curious...

It is already over 2 years since I posted if there will be Closed Caption support. Is anyone have idea will this will happen ?

Most likely when one of the developers runs into an assignment where it is required to implement this, and not much earlier.

No CC yet?

Then this software is no good for the million hearing impaired folks like myself.


Sorry to hear you have not add a CC support yet or it would been one great software to use.

Damn I installed it thinking it will have CC support and I didn't find that feature so I went and did a search in the forum finding this statement from one of the developer so off to remove the software I go.


Bill

Bill, patches for CC support are welcome. I have never seen CC stuff (as these kinds of subtitles aren't used where i live) and thus have no intrest in developing this. I guess that other developers feel like me. We already have too much stuff to do in VLC. Sorry

As another deaf user looking for broader support for closed-captioning, I'd like to add my voice to those looking for CC in VLC.

Someone should look into the way EyeTV's player resolves closed-captioning - the El Gato product is designed for recording t.v. shows, and it uses MPEG-2 encoding; EyeTV can display captions encoded in those recordings, and even preserves them when outputting for DVD.

On a related note, does anyone know if CC is supported in any of the flavors of MPEG-4/DivX/3ivx/Xvid? Or is the recourse to somehow converting CC into a subtitle stream?

I was just wondering if there was an update to Closed captioning support in VLC. More specifically can VLC decode closed captioning according to the EIA-708 spec or DTVCC (digital television closed captioning). If not does anyone know of a program that will decode these type of captions?

dont know if it works yet or not, but wanted to post that someone
did put a patch out there.

https://trac.videolan.org/vlc/ticket/77

Teletext support has already been added. As you can see the ticket is closed.

I see the ticket, but it looks open to me. I'm particularly interested in EIA-608 CC support for TV/PVR input. Interested enough to volunteer to help if I can.

Hi,

VideoLan does already have support for Displaying Closed Captioning of various types done on line 21.

The video stream or file you play must already be Closed Captioned on line 21, if it is, then simply play the video output to any TV set and the TV set will display the CC characters if you set the display of the TV set to show the Closed Captioning.

What most people do NOT understand is that in order for the source video to be Closed Captioned it MUST be at least 720x486 or there is NO line 21 to write to !!!! Dah!

There is only one software program, MacCaption, that has a patent on its method of writing to line 21 and the file dimension must be large enough to have a vertical blanking interval or line 21. That program sells for, I think about $10,000.

I am in the process of writing a program that will open a quicktime file in memory and write directly to line 21 of each frame at the correct column position for AVID and Media 100 non-linear editing systems.

If anyone would like to help me, please let me know... my email is:
tvmogul1@yahoo.com

Once I write such a program, it should be easy to write a plugin for VLC that will read line 21 if it exists which i would be glad to do and make it available for free.

Bill Sergio

Have you tried checking out DVD lab Pro?
http://www.mediachance.com/dvdlab/dvdlabpro.html

this allows you to use subtitles to use as CC

and this FREE program for creating subtitles?

http://www.urusoft.net/products.php?cat=sw&lang=1

and here is a tutorial

http://forum.videohelp.com/topic314307.html

this uses existing subtitles or you can download subtitles for most tv shows and movies in these locations if you dont have them

1. http://www.subtitlesbox.com
2. http://www.tvsubtitles.net/
3. http://www.divxtitles.com/

If not you can create them for your own show in the Subtitle Workshop and then add to DVD lab Pro.

maybe its not convenient to first have on DVD but you can always use it to sell a copy to your viewers for a extra source of income .

You can download subtitles from http://www.all4divx.com/

Closed caption support was added in the development version a few months ago. You can give it a try here: http://nightlies.videolan.org

Can VLC decode any Teletext page? like magazine page 100 and browse though the teletext on the same way as a TV set? (EBU Teletext)

Yes, on linux.

will it be available on windows as well?
regards

Not until someone makes the port.

Hey,

Anyone know whether Closed Captioning (EIA-608) is working in the latest builds. It appears as though something may be working in Linux but not in Windows (no port yet). I am working on a project and have found very few players supporting CC.

Thanks