Closed Captioning with SkyStar 2 PCI

[m4bwav]

I'm looking to capture the closed captioning from a Skystar 2 PCI card and put it into a text file.

 

Can you use DVB to do this?

 

Can you use the "B2C2 MPEG-2 Source" filter to do this?

 

In the directX utility graphedit if you right click on the filter and click on filter properties there is a text field next to CC under the heading PID, also there is a CC checkbox.

 

What are these options and how do they relate to Closed Captioning?

 

Do the pins of the filter correspond to the PID text boxes in the order they appear in the properties dialog?

 

Is there any documentation on Closed Caption with SkyStar 2?

 

 

 

If you can give me any answers to the above questions, please do not hesitiate to do so.

Edited August 1, 2005 by m4bwav

[Derrick]

isn't that a contradiction to have closed captioning and dvb?

[Mr. Bun]

Maybe this thread is of help to you.

Unless, of course, we're talking about closed captioning in North America which is, AFAIK, similar but different from the teletext-based subtitles used in Europe.

[m4bwav]

Sorry for the confusion I meant closed captioning in the general sense. I am trying to dump the captions of UK MHEG-5 digital teletext using either the DVB Source filter or the B2C2 MPEG-2 Source filter into a text file.

I know that digital teletext contains many pages of information as well as captions for tv programs. I don't want the pages, just the captioning, and I think one of the two filters might provide a way to do this.

 

Does anyone have any information of anykind on this?

 

Does anyone know where I might look to find information on this?

 

Thanks for your time

[Griga]

I've never heard of any ppossibility to get a pure text stream out of the B2C2 Filter. There's nothing about it in the SDK.

 

What you can get for sure are the teletext transportstream packets. But there's still a lot to do: Extract the data out of the TS and PES packets, unham it (= remove the error protection bits, since teletext data comes with Hamming Error Protection), read the headers, extract the desired teletext pages, parse them for control code characters etc... then you'll probably achieve what you want. But I tell you, it's a hard job - would be much easier to retrieve the teletext pages from the COM interface of DVBViewer Pro (I'm quite sure it provides them).

 

And DVBViewer Filter doesn't connect to the DVB card at all. It is supplied by the host application. So you can't use it "stand alone".

[m4bwav]

Thanks so much for the information. I will begin to look for documentation and information on the COM interface of the DVBViewer Pro,

 

If anyone knows the some good sources of information on this or any of the aforementioned questions please post them.

 

Thanks

Edited August 2, 2005 by m4bwav

[Griga]

There are already two COM threads in this forum:

 

http://www.DVBViewer.com/forum/index.php?showtopic=8449

 

http://www.DVBViewer.com/forum/index.php?showtopic=7349

 

and you may contact Lars_MQ, who created the whole stuff.

 

On the DirectShow level, you'd need a teletext decoder filter, that receives a teletext transportstream and delivers some kind of TXT format, like a video decoder, that transforms a compressed video elementary stream into BMP, or an audio decoder, that transforms an audio elementary stream into WAV. AFAIK DVB source filters do nothing but receiving and demuxing... no decoding.

 

Unfortunately I don't know such a teletext decoder, so you will have to write it yourself - or ask Google e.g. with

 

"DirectShow DVB teletext decoder filter"

 

There are some results, but at the moment I have no time to check them.

[Derrick]

Unfortunately I don't know such a teletext decoder, so you will have to write it yourself - or ask Google    e.g. with

 

"DirectShow DVB teletext decoder filter"

 

There are some results, but at the moment I have no time to check them.

 

..well have a look here http://www.no-access.de/en/en_software_data.html

[m4bwav]

Thanks for all your help here, I was able to figure out how to do what I want with the COM interface.

 

I wasn't able to find any documentation on the COM interface, maybe i didn't look hard enough. But I think it's a well done interface and if you put some links to the documentation for it somewhere, it could really help to show of the COM interface, and the DVBViewer in general.

 

You guys have done a pretty professional job with that DVBViewer program, and I wanted to thank everyone again who helped provide me with information.

 

 

Have a nice day,

Mark

Edited August 4, 2005 by m4bwav

[Guest Lars_MQ]

But I think it's a well done interface and if you put some links to the documentation for it somewhere, it could really help to show of the COM interface, and the DVBViewer in general.

But there is a documentation in the membersarea for the COM-Interface.

[m4bwav]

Oh well, my bad I guess I must have missed it.