Livetime Ultra Caption Problem

[danlo]

It is really annoying that my Livetime Ultra receiver can not display correct English caption (any caption actually). Is there any trick? Actually, the caption has never been displayed correctly since I bought the Livetime Ultra receiver. It only displays some garbage text segments. Thanks!

[pmb1010]

Originally Posted by danlo

It is really annoying that my Livetime Ultra receiver can not display correct English caption (any caption actually). Is there any trick? Actually, the caption has never been displayed correctly since I bought the Livetime Ultra receiver. It only displays some garbage text segments. Thanks!

What channel are you trying to get, that has captions?

(I never tried captioning, suppose I could try on mine see if it does the same)

[danlo]

Originally Posted by pmb1010

What channel are you trying to get, that has captions?

(I never tried captioning, suppose I could try on mine see if it does the same)

There 4 pbs channels in AMC3 that come with captions.
I suspect there is some defect about the caption programming in Livetime Ultra receiver!

[pmb1010]

Sorry, I can't figure out how to turn on captioning on the Ultra.
I looked around, and cant seem to find any option to do so.
how do you do it?

[wejones]

Originally Posted by danlo

There 4 pbs channels in AMC3 that come with captions.
I suspect there is some defect about the caption programming in Livetime Ultra receiver!

I don't know the answer, however, I'm curious how you know that the 4 PBS channels are in fact sending captioning? Ie have you seen the captions on some other DVB receiver? Or is it just that you see the captioning on OTA PBS and assume that it must be on these signals?
The closed captioning is generally sent on line 21 of the video. It would seem like as long as all the video lines are regenerated by the sat receiver, whatever brand it is, that your TV could display CC, provided that is, that your TV is so equipped. However, if the line 21 info is somehow stripped out, or somehow degraded by the MPEG conversions, that it wouldn't get through.
Those PBS channels you mention are also available via DCII channels on the same sat. I just tuned in one channel via DCII, and I was able to see CC on my TV, so it seems like the DCII system does not destroy the CC info. However, I have 4 different DVB receivers, and I don't see any captions on the DVB version of this signal. I've even used my Twinhan card with TSREADER to send the video to my Roku and to my TV, and get no captions.
So this seems to leave at least 2 possibilities, either PBS isn't sending captioning as part of the DVB video, or perhaps the DVB system is somehow stripping out this info?? I'm wondering if to save bandwidth that maybe they are only sending the visible video lines in the DVB signal??? Or perhaps there is something about the data in line 21 that the DVB process isn't able to reproduce it or something.
Anyway, interesting question, which I've seen asked several times, but have never seen a definitive answer to. Hopefully, someone can answer.

So anyway, back to my initial question, how do you know that the CC info is indeed in these DVB signals, have you seen it displayed from another DVB receiver? If so what receiver?

[DruzeTito]

there's no way to "turn on" captions on the fortec. As wejones said, if a channel has captions it is integrated in the video signal, therefore all you have to do is turn on the captions for your TV. But i don't know if the PBS DVB stream has any captions.

[pmb1010]

Originally Posted by DruzeTito

there's no way to "turn on" captions on the fortec.

yeah, DUH what was I thinking... built into the tv set not the converter box...

[wejones]

I posted this question over on satforums, and got one knowledgeable response which suggested that most of the signals in DVB format have the line 21 stripped out of the video, so it's not likely that any DVB receiver will pass the CC info on to the TV.
CC info can be sent on a separate stream, and re-constructed by the DVB receiver, but apparently this is complicated.
I did do some experimenting of a half dozen signals which when tuned via a PCI card and brought up in in TSREADER, they show that CC info is indeed present, however when TSREADER transfers the video to be viewed, the line 21 is not present, so apparently the info was sent separately, and TSREAER didn't try to re-construct it, even though it detected it. Hoping to hear a reply from the author of TSREADER to verify.
Interesting.

[danlo]

Originally Posted by wejones

I posted this question over on satforums, and got one knowledgeable response which suggested that most of the signals in DVB format have the line 21 stripped out of the video, so it's not likely that any DVB receiver will pass the CC info on to the TV.
CC info can be sent on a separate stream, and re-constructed by the DVB receiver, but apparently this is complicated.
I did do some experimenting of a half dozen signals which when tuned via a PCI card and brought up in in TSREADER, they show that CC info is indeed present, however when TSREADER transfers the video to be viewed, the line 21 is not present, so apparently the info was sent separately, and TSREAER didn't try to re-construct it, even though it detected it. Hoping to hear a reply from the author of TSREADER to verify.
Interesting.

Yes. You are right! The line 21 data area is used to store caption information. Each frame of video can transmit two characters of captioning information. There is a decoder on most TVs to decode caption information and display it. However, the receiver must handle this information carefully. For all PBS programs, the caption is indeed transmitted to TV but the Fortec receiver somehow does not handle it well. The TV can only display scrambled characters. For programs without captions, the TV displays no captions. Therefore, I strongly suspect the Fortec receiver does not handle the line 21 data area correctly! Can some body from the manufacturer of Fortec check this issue (bug)? Let us know!

[wejones]

For more info, look at Rod's post in satforums, ie:
http://forums.satforums.com/SatForum...0678.4#10678.4
and the earlier post of Hans.
They make it clear that line 21 and the other blanking lines are just not sent intact with the visible video lines, as evidenced by the fact that the video generally has only 480 lines rather than 525 (this is true for the PBS signals for example), so it's apparently not a "bug" that the fortec is not "passing" the CC info to the TV since line 21 is not part of the "video" in the mpg file being sent. Apparently, the CC info is in fact being sent, but not as line 21, but rather as a separate digital packet, and it is up to the receiver to read this and reconstruct the line 21 coding, which is not an easy thing to do. It would be nice if the fortec would reconstruct this data, but I'm guessing that the receiver would be more expensive if it did.
It sounds like it could possibly be something that could be added in a future software version, but I'm not sure that Fortec would think it was worth the investment.

[danlo]

Originally Posted by wejones

For more info, look at Rod's post in satforums, ie:
http://forums.satforums.com/SatForum...0678.4#10678.4
and the earlier post of Hans.
They make it clear that line 21 and the other blanking lines are just not sent intact with the visible video lines, as evidenced by the fact that the video generally has only 480 lines rather than 525 (this is true for the PBS signals for example), so it's apparently not a "bug" that the fortec is not "passing" the CC info to the TV since line 21 is not part of the "video" in the mpg file being sent. Apparently, the CC info is in fact being sent, but not as line 21, but rather as a separate digital packet, and it is up to the receiver to read this and reconstruct the line 21 coding, which is not an easy thing to do. It would be nice if the fortec would reconstruct this data, but I'm guessing that the receiver would be more expensive if it did.
It sounds like it could possibly be something that could be added in a future software version, but I'm not sure that Fortec would think it was worth the investment.

Well, do you really have a Fortec receiver!
The CC signal is there and Fortec does work on it but the CC is not not displayed correctly! For example, "yes" is displayed as "ys" and so on.
There must have a EIA-608/708 closed caption decoder. Otherwise, the TV would not show any characters! BTW, the problem is just like AC3 stream that Fortec simply bypasses it without trying to decode it. However, with the digital packets to get the caption out and feed it to the TV is much easier than an AC3 decoder. Yes, you are right. This can be done in software and hope Fortec will give us an update soon!

[wejones]

Originally Posted by danlo

Well, do you really have a Fortec receiver!
The CC signal is there and Fortec does work on it but the CC is not not displayed correctly! For example, "yes" is displayed as "ys" and so on.
There must have a EIA-608/708 closed caption decoder. Otherwise, the TV would not show any characters!

Actually, I have 2 Fortec receivers, which was my problem. I didn't see any hint of CC on channels that were transmitting them, on my main receiver, which is why I responded as I did. However, before responding to this message, I thought that I should try on my 2nd receiver, which is a newer one, and is one that I don't watch TV on, but use only for searching. Well, it turns out that on that receiver I get the symptoms you describe. So it looks like you're right, that the Ultra is at least trying to "encode" line 21.

Originally Posted by danlo

BTW, the problem is just like AC3 stream that Fortec simply bypasses it without trying to decode it. However, with the digital packets to get the caption out and feed it to the TV is much easier than an AC3 decoder. Yes, you are right. This can be done in software and hope Fortec will give us an update soon!

It would be "easier" if the Fortec itself put the captions on the screen, however it is not easier if the Fortec tries to reconstruct the line-21 info so that the TV can display it, which is preferred, and what it seems to be trying to do. I think encoding line 21 is much harder than just passing through AC3 info. I assume that there must be hardware solutions to this, but that is probably more expensive, so they are probably doing it via software, which I would guess is tricky. Since they are at least trying to impliment this, I'd assume that they will eventually get it right.

[danlo]

Originally Posted by wejones

It would be "easier" if the Fortec itself put the captions on the screen, however it is not easier if the Fortec tries to reconstruct the line-21 info so that the TV can display it, which is preferred, and what it seems to be trying to do. I think encoding line 21 is much harder than just passing through AC3 info. I assume that there must be hardware solutions to this, but that is probably more expensive, so they are probably doing it via software, which I would guess is tricky. Since they are at least trying to impliment this, I'd assume that they will eventually get it right.

Let me clearify one thing! Closed caption decoder is part of TV. Fortec doesn't need to encode anything, nor does it decode anything because the caption information is digitalized (ASCII code actually). What Fortec does is recognize CC packets and passes them to TV along with video signals. Since we can see some CC, Fortec does have a singal mixer. My gut feeling is Fortec can make it work by carefully examining CC packets. Maybe the CC is in unicode not ASCII because some foreign languages need two bytes for encoding. Anyhow, it is a BUG!

[Admin]

I hope Fortec Techies are watching this thread so that they can look into this issue and fix it in the next f/w release. Thanks Danlo for raising this question.

[wejones]

Originally Posted by danlo

Let me clearify one thing! Closed caption decoder is part of TV.

I agree.

Originally Posted by danlo

Fortec doesn't need to encode anything, nor does it decode anything because the caption information is digitalized (ASCII code actually).
What Fortec does is recognize CC packets and passes them to TV along with video signals. Since we can see some CC, Fortec does have a singal mixer.

This is where I hope we'll be able to agree to disagree. I agree that the Fortec doesn't need to "decode" anything, however, the process that you describe as passing the info to the TV is in reality quite complicated, and is an encoding process. Since the CC info in the sat signals is in a separate packet of info in the transport stream rather than part of a 525 line video signal, it is necessary for the Fortec to encode the CC into line 21. The "TV" video transmitted in the satellite signal is only the 480 visible lines, which doesn't include line 21 or the other VBI lines in the 525 line video sent to the TV.
It's not just mixing, because I think they have to convert the ascii data that they get from the CC packets in the sat signal into a signal with quite specific timing parameters before inserting it into line 21. I think this timing thing is likely to be their problem. I have a line grabber device with which I can extract any video line, and display it on an oscilloscope, and for example, CC data on line 21 looks much different timing wise than teletext info which can be carried on earlier scan lines, and if the timing is wrong, the TV won't display it properly.
I would guess that insertion of the CC info would be easy if the receiver had hardware specifically designed to insert the line 21 info, with crystals to accurately generate the proper timing, etc, but I'm guessing that they are doing it via software, and it just isn't working yet. My older Lifetime receiver doesn't even attempt to do it. I get nothing at all displayed on the TV, no jibberish, no black boxes, etc. I'm assuming that it just mixes the 480 lines of visible video with blank VBI lines to get the 525 video signal, and sends that to the TV, however the newer Ultra seems to be attempting to add the CC data to the VBI lines it is inserting.
Bottom line though is that whatever the reason, what they are trying to do isn't working, but at least they are trying, because of the 4 DVB receivers I have, the Ultra is the only one that even tries to encode CC info in the signal. As mentioned in other post, hopefully Fortec people can fix this in future software versions.

[quote="danlo"]

[danlo]

Originally Posted by danlo

Let me clearify one thing! Closed caption decoder is part of TV. Fortec doesn't need to encode anything, nor does it decode anything because the caption information is digitalized (ASCII code actually). What Fortec does is recognize CC packets and passes them to TV along with video signals. Since we can see some CC, Fortec does have a singal mixer. My gut feeling is Fortec can make it work by carefully examining CC packets. Maybe the CC is in unicode not ASCII because some foreign languages need two bytes for encoding. Anyhow, it is a BUG!

Here are some symptoms for Fortec development crew to revise the firmware:
"U YO" should be "YOU".
"CABLTON , OWO" should be "CAN , BLOW TOO".
"S?YE" should be "YES".
"MYOOS GESDN OH!" should be "OH! MY GOODNESS".
These instances show that the characters are correctly display but their positions are not correct! It looks like there is a 4-byte distance between any 2-byte characters. Because each frame is embedded 2 characters, the above results confirm this fact. However, the sequence of frames obviously is not consideredd in Fortec's imlementation. Can someone pass this bug report to Fortec and ask for a firmware revision?