Evaluating Digital to Analog Converter Boxes for Users of Captioning - Page 2 - AVS Forum | Home Theater Discussions And Reviews
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post #31 of 226 Old 03-01-2008, 02:52 PM
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Quote:
Originally Posted by Konrad2 View Post

So CEA 708/608 is the analog captions??

Good info here: http://www.evertz.com/resources/eia_608_708_cc.pdf

Bob

The views expressed here are my own and do not necessarily represent those of ABC, CBS, CW, FOX, MeTv, or AntennaTv; my employer; or its parent company.
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post #32 of 226 Old 03-03-2008, 10:08 AM - Thread Starter
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Quote:
Originally Posted by blacksburg98 View Post

It's PBS. The problems is that it only displays one letter on the screen each time.

Is this digital closed captioning or analog closed captions decoded through the converter box, or closed caption data passed through to the analog TV and decoded by your TV?

The answer is useful because it would help us know whether your PBS affiliate is having trouble transmitting digital closed captions or analog closed captions.

Many people have reported problems with PBS stations on digital networks, so I suspect that many PBS affiliates don't realize they need to be transmitting both digital and analog captions for their digital programming.

In a survey I set up for the captioning@yahoogroups.com, PBS is the network with the most problems showing captions for people who have HDTVs.

That suggests that the problem that you have receiving captions for PBS is not a problem of the converter box but shows a problem with the stations' transmission of captions. If it's not transmitting digital captions properly, of course you're not going to get good digital captions through your converter box. However, if you manually switch to analog captions (use the CC button to switch to CC1 for that channel only), you may be able to get by in the interim with analog captions for that program. I don't know, however, if the CC button for the converter box will work only temporarily for the channel, however, or if it changes all captioning for all channels you receive. It would really be helpful if you could do a systematic evaluation of the converter box as outlined in the first posting of this thread.

Dana
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post #33 of 226 Old 03-03-2008, 10:27 AM - Thread Starter
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Quote:
Originally Posted by Konrad2 View Post

http://www.ntia.doc.gov/ntiahome/frn..._technical.htm

says:

"Equipment must display ... (3) Close Captioning information as required by the FCC Rules in 47 C.F.R. S:15.122 and incorporate the CEA 708/608 standard."

So CEA 708/608 is the analog captions?

No. CEA-708 captions are digital. CEA-608 captions are analog.


Quote:
Assuming for the moment that the answer is "yes", does "Equipment must
display" mean that the box must decode and display the captions, or
merely pass them through, depending on the TV to decode and display them?
Older TVs don't have captions, so you could still be stuck without captions
even with a shiny new converter box?

Despite this document from NTIA, the practice seems to be that only some converter boxes will decode the captions via the converter box itself. All of them will pass through CC1 data to the analog TV, but since analog TVs can't decode digital captions, digital captions can't be viewed if there is no decoder within the converter box itself.

I personally don't understand why the practice is NOT to automatically include decoding of digital closed captions within the converter box as this seems inconsistent with other FCC rulings and is very confusing to the public. I'm afraid many people will look at the NTIA document, which clearly indicates that all coupon-eligible converter boxes should display digital captions, and will understand from this that all converter boxes will be able to display digital closed captions, and waste their $40 coupon on an online converter box that doesn't provide the digital closed captioning features they assumed it had. Once the $40 coupon is used, the consumer may not be able to apply the value of it to a converter box that DOES provide them the features desired (since so few retailers are providing more than two different kinds of converter boxes, neither of which may have digital closed captioning).

This is very, very misleading to people who need captions, and I think all the coupon-eligible converter boxes should have been required to provide access to the digital closed caption features in the first place.

In the meantime, however, if more people would do systematic evaluations of the boxes that do offer the digital closed caption features, the more people with hearing loss can find out about how the CECBs with digital closed captions meet their needs.

Dana
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post #34 of 226 Old 03-03-2008, 10:41 AM - Thread Starter
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Quote:
Originally Posted by bdfox18doe View Post

Good info here: http://www.evertz.com/resources/eia_608_708_cc.pdf

Thanks. That's interesting and well-illustrated info.

My Sharp HDTV is sometimes not decoding digital captions that the Insignia is decoding for "Lost" and some re-runs of "Law and Order" on the MyNetworkTV network. I'm puzzled as to how this could happen. The opposite situation happens sometimes; the Sharp HDTV shows 608-style captions for SD channels from a local PBS station but the converter box doesn't decode any digital captions from the station.

There's a need for a document to explain the various possibilities for why captions might not show up over digital programming. If anyone could find something like that, or even start one, that would be terrific. (I myself don't have the necessary technical expertise in audio visual science to fully understand the interactions between all the equipment.)

Dana
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post #35 of 226 Old 03-08-2008, 04:48 PM - Thread Starter
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I've provided some significant updates to the first posting of this thread, including information about which CECBs appear to have the ability to decode digital closed captions.

Most of that information was gleaned by looking at descriptions of the CECBs which stated the box had "EIA-708," "advanced closed captions," or "digital closed captions." When there was only a statement that "closed captioning" was provided, I would examine the user manual, if it was available. (BTW, the user manual for the CASTi CECB does an exceptionally nice job of explaining digital closed captions, while the table of contents for the COSHIP's manual looks like they initially were going to use section 2.6 for digital closed captions but decided not to offer this feature at all. Troubling---and very undesirable---decision on their part.)

It's been confirmed by another user on this thread that the RCA DTA800B box provides digital closed captions (but he had problems receiving DCCs on a channel from PBS).

I emailed the web site for the MaxMedia CECB and received an email back on March 4th from info@memsen.com saying, "Our box does decode digital closed captions."

There's always the chance that a manufacturer will decide to drop an advertised feature; this has apparently already happened with at least one CECB. Before ordering a CECB, therefore, you should doublecheck whether the box does in fact have the features you think it does. If buying it online, we probably ought to print out the feature list before completing the order.

If possible, let's all try to ask the online stores selling the boxes to state clearly on the description of features whether their boxes decode EIA-708 captions (especially if they do). It worries me that they're not doing so already. Customer service people could be so confused that they provide the wrong information via email just because they really don't understand the difference between EIA-608 and EIA-708 captions. I'd feel more assured if I could examine the user manual and see a direct reference to digital closed captions and other advertised features there. If possible, then, let's try to find out how to get the online user manuals for all of these boxes.

For now, six user manuals can be found through:

http://www.ezdigitaltv.com/Converter_Box.html

The CECBs described by those manuals are:

CASTi CAX-01
COSHIP N9900T
Insignia NS-DXA1
MicroGEM MG2000
Microprose MPI-500
Zenith DTT900
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post #36 of 226 Old 03-09-2008, 03:44 AM
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Dana - not strictly relevant to the thread - but thought the way live subtitles are now produced in the UK might be of interest.

http://www.bbc.co.uk/rd/pubs/whp/whp070.shtml

Because the BBC have live subtitlers in every local TV station in the UK to live-subtitle the local news, they are also able to deploy these staff, and also those working from home (who can watch an off-air feed of the show they are subtitling!) to ensure all output is subtitled efficiently. It also gives an insight into how live subs are done.

Apologies for off-topic-ness.
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post #37 of 226 Old 03-09-2008, 11:36 AM
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I have been evaluating the converter box by trying the
box with four different analog TV sets that I have at
home.

The TV power on function button on the converter remote only
works with the Sony but not on the other two that have
the RF function. Why? I have reset the box each time to
factory settings to no avail for the other TV sets. Is it true,
that the TV power on function is very limited on the remote?

I have one TV set (Sylvania) with a broken remote. I
am in the process on trying different universal
remotes. I have one with the learning feature but I
wanted to reserve that with the Sony which is my main
TV unit that is hooked up to Cable. (BTW, the Cable
hookup is only connected to the Sony and does not have
a Cable box)

The biggest issue that I have is the DTX9900 is not
sizing the digital CCD (708) font properly. By that I
mean, the CCD font is so small even when compared with
the analog CC font is large and easy to read. I can't
even select the largest font setting. I can select the
color and font styles. BTW, only two channels are
passing the 708 CC which is the PBS channels in my
area.

I don't know if the box is not working in that regard
with the CCD menu functions (in terms of font sizing)
or if it is channel provider. I'll have to find a
neighbor who has a HDTV set who can tune in the OTA
signal. Meanwhile, I'm looking for another converter
box. Any suggestions as what to get since I do not
want to duplicate the same findings?
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post #38 of 226 Old 03-09-2008, 12:15 PM - Thread Starter
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Quote:
Originally Posted by lulu8339 View Post

The biggest issue that I have is the DTX9900 is not
sizing the digital CCD (708) font properly. By that I
mean, the CCD font is so small even when compared with
the analog CC font is large and easy to read. I can't
even select the largest font setting. I can select the
color and font styles. BTW, only two channels are
passing the 708 CC which is the PBS channels in my
area.

I don't know if the box is not working in that regard
with the CCD menu functions (in terms of font sizing)
or if it is channel provider. I'll have to find a
neighbor who has a HDTV set who can tune in the OTA
signal.

It *is* important to find out if you're getting digital captions for the digital channels in the area. Many people have reported problems with captions from PBS stations, so you may not even be getting fully digital captions from that station. For example, I get captions from the SD channels of my local PBS stations that appear in the style of analog captions (black and white with solid black background), and my digital caption settings for those captions aren't applied. That's caused by the PBS station. If you're getting fixed captions from PBS, for example, then you can't change the appearance of those captions, let alone the size of the captions. If that's what's happening, that's not the fault of the converter box.


Quote:
Meanwhile, I'm looking for another converter
box. Any suggestions as what to get since I do not
want to duplicate the same findings?

If you're not getting any real digital captions in your area, you may need to hold off on getting a converter box and to work with your local TV stations to get them to broadcast both 708 and 608 captions over their digital channels sooner rather than later. Otherwise, you could be cut off from your local TV broadcasts if they never get around to fixing these problems. Your converter box won't be able to deliver you access to digital programming if no TV station is providing the necessary captions.


Quote:
The TV power on function button on the converter remote only works with the Sony but not on the other two that have the RF function. Why? I have reset the box each time to factory settings to no avail for the other TV sets. Is it true, that the TV power on function is very limited on the remote?

Resetting the CECB isn't going to affect how the remote control is set. The remote control will only be able to store the code for one TV at a time. Doublecheck the user manual about how to change the code in the remote control for the TV. If you wanted to keep this box, you may need to contact the manufacturer (or check out their web site) if you can't change the code in the remote control for the TV.

Let me ask everyone to bring up non-captioning troubleshooting problems with the general one for all CECBs at:

http://www.avsforum.com/avs-vb/showthread.php?t=980052

or with any threads that have been created for a specific CECB.

The one for this DigitalStream CECB is at:

www.avsforum.com/avs-vb/showthread.php?t=996043

Let's use this thread only for evaluations of captioning issues with CECBs or related issues so that it doesn't get off-track.
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post #39 of 226 Old 03-09-2008, 04:17 PM
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Quote:
Originally Posted by dmulvany View Post

I do hope you'll let us know whether the digital closed captioning has a caption preview that immediately shows the changes you make in the captions, what you think of the legibility of the different caption fonts, and what pushing the CC button actually does (i.e., what kind of menu it brings up).

If you can post on that here, then I can link to it from the other thread I've set up on "Evaluating digital to analog converter boxes for users of captioning" at:
http://www.avsforum.com/avs-vb/showthread.php?t=997022

Your input would certainly be valued there as well, of course.

Figured I'd just post here. I played with the CC function some more, and I seem to have the same problems outlined above. Now, mind you, I have no knowledge of the various CC formats (I have no need for CC, but just wanted to test it on the box). There is a whole array of cryptic choices: CS1, CS2, CS3, CS4, CS5, CS6, CC1, CC2, TEXT1, TEXT2. Supposedly you can also change the size, font, color, etc. of the captions. Well, I don't know if it's my ignorance, a flaw of the box, or just what's being put out by the local stations, but the only two settings that seem to work are CS1 and CC1, and they both produce that small, hard to read font mentioned above, no matter what I setup in the menu. The captions also scroll horizontally across the screen, which is very annoying as well. (The built-in captions on the analog set itself are larger, clearer, and appear as complete sentences at a time, not scrolled like some bank's promotional marquee.)

So, FWIW, that is what I find. It's no skin off my own nose, since I don't use the captions, but I can well understand that a hearing-impaired person would certainly not want to use this unit. (Again, though, unless I'm just ignorant and am not hitting the right buttons...)
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post #40 of 226 Old 03-09-2008, 05:21 PM - Thread Starter
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Quote:
Originally Posted by Stanislav View Post

Figured I'd just post here. I played with the CC function some more, and I seem to have the same problems outlined above. Now, mind you, I have no knowledge of the various CC formats (I have no need for CC, but just wanted to test it on the box). There is a whole array of cryptic choices: CS1, CS2, CS3, CS4, CS5, CS6, CC1, CC2, TEXT1, TEXT2. Supposedly you can also change the size, font, color, etc. of the captions. Well, I don't know if it's my ignorance, a flaw of the box, or just what's being put out by the local stations, but the only two settings that seem to work are CS1 and CC1, and they both produce that small, hard to read font mentioned above, no matter what I setup in the menu. The captions also scroll horizontally across the screen, which is very annoying as well. (The built-in captions on the analog set itself are larger, clearer, and appear as complete sentences at a time, not scrolled like some bank's promotional marquee.)

Thanks very much for your input, Stanislav.

I haven't heard of "CS1" before, but "Service 1" on the Insignia box refers to the English language setting for digital captions, so my guess is that "CS1" refers to digital captions using Service 1. Users might only be able to change the size of captions if the user chooses the "CS1" setting as that is a selection of digital captions, while the CC# choices are analog only.

If you're only using the CC button, this may not work to set up permanent captioning settings. CC buttons aren't standardized and may be used by one manufacturer for a temporary change in the captions, or by another manufacturer for a very quick and easy menu. The only way to set up a permanent change may be by going into the Menu setting.

Still, it sounds like there are problems with how the DigitalStream DTX9900 has been designed with respect to digital closed captions. There's a chance that there's something abnormal about how local TV stations are transmitting their digital captions, but there should be some noticeable differences among the different stations.

I may see if I can get a local Radio Shack to demonstrate this CECB in the store. I know what the Insignia can do for the different local channels here (and I've never seen problems like what you've described), so I can compare what I see from the DigitalStream with what I've seen the Insignia do.

If those problems are duplicated here, though, that sounds really horrible for people who were counting on getting usable digital closed captions---and who may blow their $40 coupon on this CECB.

Doesn't the user manual provide any useful assistance about how to select the digital captions? (I'm hoping lulu8839 can answer this question.)
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post #41 of 226 Old 03-09-2008, 09:07 PM
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Quote:
Originally Posted by seatacboy View Post

Many American viewers who are not necessarily "hearing impaired" use closed captioning at certain times. Closed captioning is particularly effective in public lounge areas of restaurants, bars and other locations with a lot of ambient noise. Even in the home, some viewers prefer viewing as well as seeing the spoken dialogue.

While the broadcasters may bear much of the blame for these problems, I recall NTIA's specifications referred to the importance of the "robustness" of the STB design. While that may have referred to hack-resistance, it also presumably means the CECBs should be freeze-resistant and crash resistant.

I'm glad you brought this up. I love to use my closed captioning when watching movies, or when watching music programs (you get lyrics!), or sometimes just watching a show where someone's speaking with an accent I can't understand. Closed captioning's technology may have started out being just for the deaf, but that doesn't mean hearing people can't use it, as well!
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post #42 of 226 Old 03-09-2008, 09:36 PM - Thread Starter
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Quote:
Originally Posted by MissIrisMG View Post

I'm glad you brought this up. I love to use my closed captioning when watching movies, or when watching music programs (you get lyrics!), or sometimes just watching a show where someone's speaking with an accent I can't understand. Closed captioning's technology may have started out being just for the deaf, but that doesn't mean hearing people can't use it, as well!

Certainly many people use captioning who don't have a hearing loss. That's why the title of this thread is "Evaluating Digital to Analog Converter Boxes for Users of Captioning" and doesn't assume that only deaf and hard of hearing people use captioning. However, captioning is especially important for deaf and hard of hearing people who can't reliably understand spoken communication without it. (Captioning is also important for many non-native speakers of English and people with auditory processing disorders and perhaps people with other kinds of disabilities as well.)

With all these users of captioning, though, we really need systematic evaluations of the captioning features from the different CECBs. I've outlined an evaluation process and 12 questions to be answered in the first posting of this thread. Other CECBs can be purchased in stores right now that offer digital captions: the RCA and Magnavox at Walmart, the DigitalStream at RadioShack and the Zenith at Radio Shack and Circuit City. (The Insignia is at Best Buy but I've already been evaluating that in the second posting of this thread.) Nowhere else have there been systematic evaluations of captioning features, so please help out here by systematically evaluating a CECB yourself (as outlined in the first posting) and sharing your input on this thread. If we don't do it here, it may never happen, and due to the time limits of the 90-day period for coupons, those people who have coupons already or coming soon need those evaluations sooner rather than later.

Dana
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post #43 of 226 Old 03-10-2008, 03:23 AM
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It should be noted that the "analog" EIA-608 captions are not really "analog" in the ATSC signal. In fact, they are transmitted digitally just like the EIA-708 captions, and in the very same place in the MPEG-2 bitstream (video elementary stream picture user data).

In essence, all the captions in an ATSC signal are EIA-708, but the FCC has mandated that EIA-608 captions are replicated and always sent in addition to any EIA-708 captions. In the picture user data syntax, there is an identifier to indicate whether a byte is for EIA-608 captions or EIA-708 captions.

The ATSC receiver is actually reconstructing the line 21 analog captions on it's composite or s-video output based on digital information in the ATSC bitstream.

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post #44 of 226 Old 03-10-2008, 03:48 AM
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Quote:
Originally Posted by dr1394 View Post

The ATSC receiver is actually reconstructing the line 21 analog captions on it's composite or s-video output based on digital information in the ATSC bitstream.

Ron

Yep - that is the same technique used by DVB systems to provide the same teletext/subtitle services we have on PAL/SECAM analogue (World Systems Teletext) - with either the receiver decoding the WST packets and burning them into the video, or the receiver converting the WST packet stream into VBI data and inserting it in blanking on an SD signal, so that a TV with teletext decoding can display the text service itself.

Some receivers do a combination of the two - decoding subtitles and burning them into the video as text, but also re-inserting the teletext data into blanking for display decoding. (Sky receivers do this for example)

(It all gets more complex with HD interconnects - where receiver display is a must as HDMI/Component HD interconnects don't carry VBI WST in a form that can be decoded in the TV.)
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post #45 of 226 Old 03-10-2008, 01:27 PM
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Yeah, with more experimentation, it looks like (a)you have to choose "user" in the menu for it to utilize your settings and not the defaults, (b)"CS1" is indeed the only setting that works with the changes (I don't know what CS2, etc. are for -- none of them work at all -- maybe for future standards?), (c)the largest font is not very large at all, and (d)no matter what combination of font, color, background you choose, the damn letters sparkle and shimmy on the screen to the point of distraction. Sure, this is being viewed on a very inexpensive 13" analog, but similar lettering in the TV picture itself doesn't do this, just the captions, so I don't think it's the set that's the problem.

Anyway, that's probably as far as I'll go with playing around with this CC stuff. Y'all can work it out the rest of the way on your own.
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post #46 of 226 Old 03-10-2008, 01:54 PM
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Quote:
Originally Posted by Stanislav View Post

Yeah, with more experimentation, it looks like (a)you have to choose "user" in the menu for it to utilize your settings and not the defaults, (b)"CS1" is indeed the only setting that works with the changes (I don't know what CS2, etc. are for -- none of them work at all -- maybe for future standards?),

Suspect CS2 etc. are for alternate caption streams. In some territories it isn't unusual to have more than one subtitle stream on programmes (say English and Spanish in the US, English and French in Canada, English and Welsh in Wales etc.) I guess that CS1 and CS2 would let you chose between languages?

Quote:


(c)the largest font is not very large at all, and (d)no matter what combination of font, color, background you choose, the damn letters sparkle and shimmy on the screen to the point of distraction. Sure, this is being viewed on a very inexpensive 13" analog, but similar lettering in the TV picture itself doesn't do this, just the captions, so I don't think it's the set that's the problem.

Unless you are using S-video you are using a composite (either baseband via RCA phonos or via RF) connection. Composite signals suffer from cross colour and cross luma - where high frequency detail (like the sharp edges of a cheap non-/poorly-antia aliased character inserter) causes chroma interference. This isn't an issue in most internal closed caption decoders because the captions can be inserted AFTER Composite decoding, into the RGB or component internal signals before going to the tube drives - but is if you are decoding composite captions. It shouldn't be an issue with S-video.

Very fine text will also potentially "twitter" as a result of interlacing - particularly on fine vertical detail. This would be at frame, not field, rate as very fine static vertical detail is only present in alternate fields

It isn't a fault of the set top box per se (though decent anti-aliased characters will have fewer HF edges and should thus "shimmer" less) but more a function of the interconnect used - though better decoders in more expensive sets may cope better. You would probably see it on subtitles inserted by a DVD player (and not by the TV) when connected composite?
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post #47 of 226 Old 03-10-2008, 02:47 PM
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Quote:
Originally Posted by sneals2000 View Post

Suspect CS2 etc. are for alternate caption streams. In some territories it isn't unusual to have more than one subtitle stream on programmes (say English and Spanish in the US, English and French in Canada, English and Welsh in Wales etc.) I guess that CS1 and CS2 would let you chose between languages?

Could be. I haven't found any broadcasts with dual-language audio yet (although for some reason, CBS shows always show an SAC that merely turns out to be the same English audio, in poorer quality), which is where I would expect the possibility of dual-language captions. Still doesn't explain what CS3 through CS6 are for, unless there are plans afoot to do shows with subtitles in 6 different languages.

Quote:
Originally Posted by sneals2000 View Post

Very fine text will also potentially "twitter" as a result of interlacing - particularly on fine vertical detail. This would be at frame, not field, rate as very fine static vertical detail is only present in alternate fields

It isn't a fault of the set top box per se (though decent anti-aliased characters will have fewer HF edges and should thus "shimmer" less) but more a function of the interconnect used - though better decoders in more expensive sets may cope better. You would probably see it on subtitles inserted by a DVD player (and not by the TV) when connected composite?

Just for the halibut, I pulled out a DVD that had subtitles, and no, they did not twitter like the captions generated by the DTX990. They are not perfectly sharp (but then, nothing really is on a cheap set like this), but they did not do the "Twinkle, Twinkle, Little Star" number. Maybe the difference between the captions being an integral part of the original source, as opposed to being generated by the box and overlaid on an existing signal?
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post #48 of 226 Old 03-10-2008, 05:21 PM - Thread Starter
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Originally Posted by Stanislav View Post

Could be. I haven't found any broadcasts with dual-language audio yet (although for some reason, CBS shows always show an SAC that merely turns out to be the same English audio, in poorer quality), which is where I would expect the possibility of dual-language captions. Still doesn't explain what CS3 through CS6 are for, unless there are plans afoot to do shows with subtitles in 6 different languages.

I think the CS2, CS3, etc is the equivalent of Service 2, Service 3, etc. and was simply a way of future-proofing the device in case a TV station wanted to broadcast captions in languages other than English. CS2 might also be used to broadcast captions at a slower reading rate (like for young children who can't read quickly), or conversely, at a faster rate for deaf or hard of hearing parents who are watching "Sesame Street' with their hearing children. (The normal captioning for Sesame Street is at a very low reading rate and doesn't actually follow the dialog.)


Quote:


Just for the halibut, I pulled out a DVD that had subtitles, and no, they did not twitter like the captions generated by the DTX990. They are not perfectly sharp (but then, nothing really is on a cheap set like this), but they did not do the "Twinkle, Twinkle, Little Star" number. Maybe the difference between the captions being an integral part of the original source, as opposed to being generated by the box and overlaid on an existing signal?

Now, that is interesting!

I think you're talking about the same kind of problem I had noticed earlier in this thread, though it sounds worse with the DigitalStream. Perhaps the subtitles do become part of the overall video image, and the way that the captions are inserted by the DigitalStream sounds inferior.

I went to Radio Shack today to try to get a demo of the Digital Stream, but the personnel said they wouldn't do it (they don't want to open boxes to demonstrate anything). I confirmed the ONLY way I could see for myself about digital caption problems would be to buy this, even though I'd heard two other people complain about the digital captions, and that I would need to return it if I didn't like it. Then the personnel prepared to sell me a converter box which turned out to be the Zenith (without telling me they hadn't found the DigitalStream), and then said they didn't have the DigitalStream in stock. (Along the way, it was very clear none of the three personnel had any idea these converter boxes decoded digital captions.)

I decided to go ahead and buy the Zenith to check that out as there might be slight differences between that one and the Insignia, even though thy both have the same chip. More on that later.

Stanislav, thanks very much for providing us more feedback on the DigitalStream. Sounds like the digital captions are too small to compete with a TV's built-in analog captions, and that the manufacturer just didn't implement those features well. On the Insignia, the largest font, Font 7, covers the entire width of the screen when all 32 characters are used, so it's possible to make digital captions large. My Sharp HDTV doesn't make its digital captions terribly large, but at least they're easy to read.
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Quote:
Originally Posted by Stanislav View Post

Could be. I haven't found any broadcasts with dual-language audio yet (although for some reason, CBS shows always show an SAC that merely turns out to be the same English audio, in poorer quality), which is where I would expect the possibility of dual-language captions. Still doesn't explain what CS3 through CS6 are for, unless there are plans afoot to do shows with subtitles in 6 different languages.

BBC Prime, a pan-European Pay-TV operation operated by the BBC in Europe is broadcast in English language audio but with subtitles in the following languages : Swedish, Danish, Norwegian, Czech, Polish, Romanian, Hungarian, Italian, Hebrew and Serbo Croat, as the channel is broadcast in territories using these formats. Obviously there are multiple versions of the channel for different pay-TV platforms - but some platforms cover multiple language territories, and other pan-European channels do similarly - certainly Swedish, Danish and Norwegian subtitles are common on pan-Nordic channels or they were - hence DVB and the analogue Teletext system coped with a very large number of simultaneous subtitle feeds (on Teletext they appeared on different page numbers that you entered manually, on DVB receivers you usually select your native language and subtitles are flagged with their language - a bit like DVD players)

I suspect the ATSC had a similar mind set - as the ATSC regions include French, Spanish and English speaking communities in large numbers, and smaller numbers of more minority language communities ? If a show has SAP audio in Spanish or French, then it could be expected to have subtitles as well?

I suspect that one reason the DVB subtitles are bitmap based (like DVDs) rather than character based (as Teletext and ATSC and NTSC closed captions are) is that the subs are not tied to founts in the receiver - so complex character sets are handled by the broadcaster originated the captions, meaning each receiver doesn't have to have full Japanese, Chinese, Greek, Hebrew, Arabic, Russian etc. typefaces built in to be able to display subtitles in these formats.

Quote:
Just for the halibut, I pulled out a DVD that had subtitles, and no, they did not twitter like the captions generated by the DTX990. They are not perfectly sharp (but then, nothing really is on a cheap set like this), but they did not do the "Twinkle, Twinkle, Little Star" number.

Suspect the DVD player does a better insertion job - and the DVD typefaces (like DVB subtitles, chosen by the DVD mastering people not the player itself, as DVD subs are bitmapped) - even via a composite connection (component or S-video will be better still). DVD subtitles are quite "chunky" - so may not have as much "fine" detail in them?

Quote:
Maybe the difference between the captions being an integral part of the original source, as opposed to being generated by the box and overlaid on an existing signal?

DVD subtitles are generated in the DVD player (I wasn't talking about DVD replays with closed captions that are generated in the TV, nor a DVD release with "burned in" subtitles) and inserted in a very similar way to closed captions being decoded in an external set top box. Suspect the twinkling and twittering are a result of the poorer quality founts?
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post #50 of 226 Old 03-10-2008, 05:54 PM
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Quote:
Originally Posted by dmulvany View Post


----snip----

Here's my own current and not necessarily complete list of CECBs
with digital closed captioning (and some other features):
Artec T3APro
CASTi CAX-01 (CC button on remote)
Daewoo DAC-100 (according to user guide on FCC site)
DigitalSTREAM D2A1D10
DigitalSTREAM D2A1D20
DigitalSTREAM DTX9900 (Can pass through analog channels)
Insignia NS-DXA1
Magnavox TB100MW9 (Can pass through analog channels)
MaxMedia MMDTVB03 (S-video, Smart Antenna interface, may pass through analog channels)
MicroGEM MG2000
MicroProse MPI-500 (Buttons on box for menu, channels, etc. Though claimed as a feature,
Smart Antenna interface is not shown on box or documented in manual---status unclear.)
Philco TB100HH9 (Can pass through analog channels)
Philco TB150HH9 (Can pass through analog channels, Smart Antenna interface)
RCA DTA800
RCA DTA800B (Smart Antenna interface)
TATUNG TDB3000 (Smart Antenna interface)
Tivax STB-T9 (Smart Antenna interface)
Zenith DTT900
Zentech DF2000 (7 day EPG, CC button)
The links for the different CECBs are to documents that show that the CECB has
digital (EIA-708) closed captioning decoding.

----snip----

Dana Mulvany
Rockville, MD

I need to update my spread sheet with links to manufacturer or retailer websites
(preferably the horse's mouth), indicating the source of various information.
I've been able to confirm nearly all of the above and will incorporate it into next update, however
first I have a few questions:

1. There are almost no RCA DTA-800/800A reports and it uses a SoC chip from a different
manufacturer. So I'll use a question mark "?" until someone provides specific confirmation.
[Zoran's Jan2007 Press Release said RCA DTA-800A would use SupraHD 741...with Smart Antenna I/F.]
[But LATER Oct2007 VU-graph said RCA DTA-800 used SupraHD 640 with Cascade 220...go figure.]
[Quite frankly, I'm not so sure very many of these "prototypes" ever made it to retail...]

PS: Much more numerous DTA-800B model (with Broadcom SoC) has DCC.

2. Without a copy of the Philco TB150HH9 User Manual, I've been unable to confirm DCC feature.
Does anyone have a source of info for this model, or should we presume DCC is very likely since
it was in TB100HH9 model? [Works for me.....]

3. I have been unable to confirm DCC for Tatung TDB-3000 (model is missing from their website).
Anyone know source of this info, other than (the unknown sourced) info on ezddigitaltv.com?
[I'll use "DCC?" until someone provides specific confirmation.]

4. I've been unable to confirm DCC for Zentech DF2000 (Can't find on any website).
Anyone know source of this information, other than (unknown sourced) info on ezddigitaltv.com?
["Zentech" websitesss are deadendsss. Found Skardin Industrial Corp address/phone, no website.]
[I'll use "DCC?" until someone provides specific confirmation.]

============================
I'm also looking for a link to DigitalStream DTX9900, Zenith DTT900, et. al. User Manuals.
And are there any differences wrt Insignia NS-DXA1?

FYI: FCC EAS (Emissions Test) website only had the User Manual for Insignia LSX-300-4DM
(with Smart Antenna I/F). EAS website only lists (same) few boxes so far. I'll also update Daewoo
features since website is back up after weekend maintenance.

PS: Microprose originally had Smart Antenna feature listed on their website....but it has been
removed and the MPI-500 User Manual clearly does not describe this feature, nor does it show
a Smart Antenna I/F connector.
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I emailed the contact at www.convertmytv.com (info@memsen.com) for the MaxMedia CECB about nothing being said publicly about their device having analog pass-through and EIA-708 captions. Here's the response I got:

______________
Dana,

Thank you for your interest in our MMDTVB03.

As you know, our box does feature analog passthrough capability for EIA-708 captions

We are not posting a full feature yet due to some regulatory issues with some of our competitors
and their lack of this above stated capability ... its a political issue.

We will have an online USER MANUAL available shortly. Please request one at
support@maxmedia-usa.com

Thank you,
Customer Service
www.convertmy.tv
_____________________


Oh boy. The person confused pass-through of analog captions with "analog pass-through of analog channels." It's also not possible to pass-through digital caption data to an analog TV, and the person who answered didn't appear to understand the difference between EIA-708 and EIA-608 captions.

There shouldn't be any legal problem for a converter box to pass through analog channels, to decode digital captions, to have S-video output or to provide a Smart Antenna interface, so what they said about not wanting to post their full features doesn't make sense to me.

Buyer beware. I'm going to wait for the user manual to be posted online OFFICIALLY as proof of what the MaxMedia CECB's features are, and I suggest everyone demand and look at the user manual first before buying. I'm not certain this CECB actually passes through analog channels or provides digital closed captions, and I haven't seen any public proof that this CECB does so. There *may* be some language translation problems getting in the way.

Dana
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post #52 of 226 Old 03-11-2008, 12:20 PM - Thread Starter
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Quote:
Originally Posted by dr1394 View Post

It should be noted that the "analog" EIA-608 captions are not really "analog" in the ATSC signal. In fact, they are transmitted digitally just like the EIA-708 captions, and in the very same place in the MPEG-2 bitstream (video elementary stream picture user data).

In essence, all the captions in an ATSC signal are EIA-708, but the FCC has mandated that EIA-608 captions are replicated and always sent in addition to any EIA-708 captions. In the picture user data syntax, there is an identifier to indicate whether a byte is for EIA-608 captions or EIA-708 captions.

I've heard references to EIA-708B captions; perhaps those are the specific captions that are advanced, while the EIA-608 captions are supposed to be included along with the EIA-708B captions to form the entire EIA-708 standard? I'm having trouble finding clear information about this.

Quote:


The ATSC receiver is actually reconstructing the line 21 analog captions on it's composite or s-video output based on digital information in the ATSC bitstream.

Ron

The EIA-608 captions would also reconstructed via the RF output. (Most of the CECBs don't have S-video output; they're all required to have the composite video and RF output.)
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Quote:
Originally Posted by holl_ands View Post


1. There are almost no RCA DTA-800/800A reports and it uses a SoC chip from a different
manufacturer. So I'll use a question mark "?" until someone provides specific confirmation.

That sounds fine.

Quote:


2. Without a copy of the Philco TB150HH9 User Manual, I've been unable to confirm DCC feature.
Does anyone have a source of info for this model, or should we presume DCC is very likely since
it was in TB100HH9 model? [Works for me.....]

Works for me, too, especially since it's described as having DCC (digital closed captions) at ezdigitaltv.com.

I've updated the list of CECBs with DCCs at posting #1 with more links to supporting documentation, referring to user manuals whenever possible (or to a page containing a link to a user manual), and there's now a link to the user manual for the TB100HH9.

Unfortunately, there is still so much confusion about digital closed captions that some references to digital closed captions may have been erased in the list of features because the writer thought this was redundant information. So some of the pages that used to say the CECB had digital closed captions seem to have been changed and may no longer say they do---and it may be a result of the writer's confusion rather than a dropping of the feature. The Insignia page now doesn't say it has DCC, for example, and I think it used to. (The current link points to that page, which contains a link to the user manual.)


Quote:


3. I have been unable to confirm DCC for Tatung TDB-3000 (model is missing from their website).
Anyone know source of this info, other than (the unknown sourced) info on ezddigitaltv.com?
[I'll use "DCC?" until someone provides specific confirmation.]

The linked list of features states:

"Closed Captioning
EIA-708 & EIA-608"

It's up to you, but I thought that was specific enough.

I think it would be highly desirable to see the user manual for all these CECBs, but it's still useful to indicate which ones have been described as having the DCCs---and to advise people to make sure of this before buying the CECB.

Quote:


4. I've been unable to confirm DCC for Zentech DF2000 (Can't find on any website).
Anyone know source of this information, other than (unknown sourced) info on ezddigitaltv.com?
[I'll use "DCC?" until someone provides specific confirmation.]

The linked list of features from ezdigitaltv.com stated:

"Closed Caption: Digital closed captions offering multiple font sizes, colors and backgrounds."

Again, when there's that much specificity, I'm inclined to think the CECB probably does have that feature.

Quote:


============================
I'm also looking for a link to DigitalStream DTX9900, Zenith DTT900, et. al. User Manuals.
And are there any differences wrt Insignia NS-DXA1?

I'll replace the current links with links to the user manuals if that information becomes known to me.

I'm not sure what you mean about differences with respect to the Insignia. I'm currently comparing this to the Zenith DTT900, though, but need to put the two boxes in the same room for a definite comparison between the 2.

Quote:


PS: Microprose originally had Smart Antenna feature listed on their website....but it has been
removed and the MPI-500 User Manual clearly does not describe this feature, nor does it show
a Smart Antenna I/F connector.

Thanks. I erased the reference to the possibility of a Smart Antenna interface.


I have separated the MaxMedia box out of the list because I'm not comfortable relying on email from a confused-sounding customer service representative as proof that the box has DCCs.
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Quote:
Originally Posted by dmulvany View Post

With all these users of captioning, though, we really need systematic evaluations of the captioning features from the different CECBs. I've outlined an evaluation process and 12 questions to be answered in the first posting of this thread. Other CECBs can be purchased in stores right now that offer digital captions: the RCA and Magnavox at Walmart, the DigitalStream at RadioShack and the Zenith at Radio Shack and Circuit City. Nowhere else have there been systematic evaluations of captioning features, so please help out here by systematically evaluating a CECB yourself (as outlined in the first posting) and sharing your input on this thread. If we don't do it here, it may never happen, and due to the time limits of the 90-day period for coupons, those people who have coupons already or coming soon need those evaluations sooner rather than later.

Dana

Well, before I do that, I first have to evaluate whether the Magnavox box I bought from Wal-Mart will even work with my TV and DVD recorder. After that, I'll be happy to let you know my impressions of the Closed Captioning function. If the tuner's CC doesn't work well, I guess I can override it with that of my television. If it does, I'll keep it, if not, I'll look for a DVD recorder with a tuner! Wal-Mart has a liberal return policy, and I bought it even though I qualify for a coupon (which I should have been able to download rather than wait for it in the mail, but that's OT). We'll see what happens.

At any rate, I'm sorry if you took my response as threadjacking, it wasn't the intention. I'll be lurking until I find out what you need to know, unless someone posts data for it first, as it will be interesting to see what you actually do with all this data...

Thanks
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Originally Posted by MissIrisMG View Post

Well, before I do that, I first have to evaluate whether the Magnavox box I bought from Wal-Mart will even work with my TV and DVD recorder. After that, I'll be happy to let you know my impressions of the Closed Captioning function.

I'm very glad to hear you'll be evaluating a CECB. FYI, no one else has yet indicated they'd be evaluating the digital closed captioning of the Magnavox.

Unfortunately, there's been a lot of problems reported with the Magnavox CECBs not even turning on, with one person on the AVS forum saying the first two boxes he picked up were dead right out of the box. So you definitely *do* need to find out if it will even work at all, let alone with your TV! Of all the CECBs bought from stores so far, the Magnavox CECBs appear to have the highest rate by far of being "dead on arrival."

Quote:


If the tuner's CC doesn't work well, I guess I can override it with that of my television. If it does, I'll keep it, if not, I'll look for a DVD recorder with a tuner! Wal-Mart has a liberal return policy, and I bought it even though I qualify for a coupon (which I should have been able to download rather than wait for it in the mail, but that's OT). We'll see what happens.

You may be very glad you didn't buy it with a coupon since you'll be able to get your money back in full if you're not happy with it.

Quote:


At any rate, I'm sorry if you took my response as threadjacking, it wasn't the intention.

No need to apologize at all. We've gotten absolutely terrific information here related to captioning that might not be considered strictly related to evaluating converter boxes, but I think we've really benefited from them. I was worried, however, that despite dozens of messages, no one else had yet answered for any CECB the ten questions (now 12) which I had listed in the first posting of this thread. (We don't know if any other CECB's remote control is accessible to blind folks, for example.)

There are already problems surfacing (like with the DigitalStream and the RCA 800B, which might stop working properly with some TV stations if the background is set to transparent.) There's a definite need to find out more.

Quote:


I'll be lurking until I find out what you need to know, unless someone posts data for it first, as it will be interesting to see what you actually do with all this data...

What I (and millions of other people) need to know is the information requested in the first posting for all the CECBs with digital closed captioning via the systematic evaluation process outlined in that posting. The second posting shows how that was done with the Insignia. The photos are optional but certainly desirable since they can let people make their own judgments.

The questions in the first posting can be copied and pasted into a new document, with answers inserted in between the questions. (Might be safer to create the evaluation in something like Word or WordPad first so you can save it and work on it over time, rather than try to type it up online in one sitting. It could then be pasted into a new posting on this thread when finished.)

Dana
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post #56 of 226 Old 03-12-2008, 01:47 AM
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Quote:
Originally Posted by dmulvany View Post

I've heard references to EIA-708B captions; perhaps those are the specific captions that are advanced, while the EIA-608 captions are supposed to be included along with the EIA-708B captions to form the entire EIA-708 standard? I'm having trouble finding clear information about this.

The ATSC specification is available here:

http://www.atsc.org/standards/a_53-P...-w-Amend-1.pdf

See section 6.2.3

The EIA-708B specification isn't public. However, I can show you how it works with a bitstream example.



I've highlighted the caption data in red. Here's the breakdown.

00 00 01 B2 = user_data_start_code

47 41 39 34 = ATSC_identifier ("GA94" in ascii for Grand Alliance 1994)

03 = user_data_type_code (0x03 = cc_data)

54 = 01010100 = process_cc_data_flag = 1, additional_data_flag = 0, cc_count = 0x14 or 20 decimal

FF = reserved

FC = NTSC line 21 field 1 (EIA-608)

E5 6D = two characters of cc_data (the letters "em" in the CC1 service)

FD = NTSC line 21 field 2 (EIA-608)

52 BA = two characters of cc_data (some other service, possibly XDS)

FF = DTVCC packet header

46 29 = two bytes of DTVCC (EIA-708)

FE = DTVCC packet data

6C 65 = two bytes of DTVCC (EIA-708)

FE = DTVCC packet data

61 73 = two bytes of DTVCC (EIA-708)

FE = DTVCC packet data

65 20 = two bytes of DTVCC (EIA-708)

FE = DTVCC packet data

74 68 = two bytes of DTVCC (EIA-708)

FE = DTVCC packet data

03 00 = two bytes of DTVCC (EIA-708)

FA = cc_valid = FALSE

00 00 = filler

The FA 00 00 sequence is repeated 11 more times to fill out the cc_count of 20.

FF = marker_bits (end of user_data)

00 00 = stuffing to align the bitstream

Ron

HD MPEG-2 Test Patterns http://www.w6rz.net
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Quote:
Originally Posted by dmulvany View Post

This is very, very misleading to people who need captions, and I think all the coupon-eligible converter boxes should have been required to provide access to the digital closed caption features in the first place.

The Coupon-eligible boxes are required to provide the SAME functionality as current analog television provides. That means outputing NTSC-compatible video. S-video, digital captions, electronic guides, et cetera are all considered "optional" extras and are not mandatory.

Repeat: They are only required to provide the SAME functionality as televisions have now. Extras are not required.



Also, I want to correct a few minor errors. The box does not "passthrough" analog captions, because there is no analog. The signal is completely digital. Inside that digital signal is data that holds the EIA-608 captioning. The EIA-608 digital data is stripped-out and fed to line 21 on the NTSC analog video.

Thus the EIA-608 captions are digitally generated by a computer, and converted to an analog signal.

Not passed-through.
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post #58 of 226 Old 03-12-2008, 12:19 PM - Thread Starter
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Quote:
Originally Posted by rrrrrroger View Post

Also, I want to correct a few minor errors. The box does not "passthrough" analog captions, because there is no analog. The signal is completely digital. Inside that digital signal is data that holds the EIA-608 captioning. The EIA-608 digital data is stripped-out and fed to line 21 on the NTSC analog video.

Thus the EIA-608 captions are digitally generated by a computer, and converted to an analog signal.

Not passed-through.

I think the reason that the term "passed through" has been used by people and organizations other than myself is to emphasize that the EIA-608 captions must be present in the televised signal already and that the CECB is therefore required to "pass through" the EIA-608 caption data if this data exists. The CECB cannot do this for EIA-608 captions that are not already present in the televised signal. Some people have erroneously thought that the CECBs could convert EIA-708 captions to EIA-608 captions, which isn't the case.

The term "relaying" could be used with respect to the EIA-608 captioning data as I think that communicates that the EIA-608 captioning data has to exist in the first place. Deaf and severely hard of hearing people use relay services to understand spoken communication; the meaning is intended to come through intact and word-for-word even if the method of delivery is different. Thus although EIA-608 data is sent out digitally by the TV stations, the CECB relays this data to the analog TV by converting the data into a form that the analog TV can understand. The information remains exactly the same (or should).

I think the general public, however, will understand the term "pass-through" of the EIA-608 captioning data more easily than relaying; most people will absolutely not want to get into the mechanics about how this is done, and in many situations, it is kinder and more effective to speak to them in language they can understand than to insist on using technically precise language that's much too difficult, and irrelevant, for them to understand.

EIA-608 captions are often described as analog captions (even if they're sent digitally) because these are the only kinds of captions that can be decoded by analog TVs, and that language is easier for most consumers to understand. The use of the term "analog captions" should not be taken to mean that the person using this term believes they're sent via analog signals.

rrrroger, you brought in a quote of a message from another thread, which was out of context for this thread, particularly since you could have continued the discussion there and I had already addressed what you said on the other thread by stating that there are required features available from CECBs that are not available on analog TVS now. Please don't bring quotes from other threads here that are not directly related to evaluations of CECBs and which will bewilder everyone else here; if you want to continue the discussion, do so on the original thread or PM me.
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post #59 of 226 Old 03-12-2008, 05:01 PM - Thread Starter
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Quote:
Originally Posted by dr1394 View Post

The ATSC specification is available here:

http://www.atsc.org/standards/a_53-P...-w-Amend-1.pdf

See section 6.2.3

The EIA-708B specification isn't public. However, I can show you how it works with a bitstream example.

Interesting.

How can we refer just to the digital captions in a way which doesn't include the EIA-608 captions that are also expected to be part of the bitstream?

There's a lot of confusion about digital closed captions, with some people believing that ATSC tuners can downconvert EIA-708 captions that don't have EIA-608 data within them to EIA-608 captions, or that it would be easy for them to do so----and that there's no need to continue broadcasting EIA-608 data.

As I understand it, though, the CECB boxes wouldn't be able to provide EIA-608 data to analog TVs if there were no EIA-608 captions in the original broadcast. They might have the optional feature to decode EIA-708 captions, but that is different from providing the EIA-608 data to the analog TVs to decode.

BTW, does the ability to decode EIA-708 captions automatically mean the ability to decode EIA-608 captions?

Anyway, I'm wondering how clear the FCC has been about the need to provide both types of captions after the cessation of analog broadcasts. If TV station engineers haven't been made aware that they still need to be transmitting both kinds of captions, and if equipment manufacturers and other people in the industry haven't understood this either, then many people with hearing loss with CECBs that don't decode captions could be without access to captions for a significant period of time.

In the DC area, there are four stations (WJLA, WTTG, my20, WETA) that don't routinely send both types of captions over digital channels, and I'm wondering if that's because of a failure by the FCC to communicate the necessity of both kinds of captions at every point along the way of transmitting, receiving and recording TV signals.

(Analog TV users who depend on captioning may really be hurt by all this confusion, but they'd be better off if they got a CECB with good digital captioning features which can provide access to both types of captions.)

Dana
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post #60 of 226 Old 03-12-2008, 05:53 PM - Thread Starter
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Using the TiVo with a CECB for open-captioned recordings

One interesting way of using the digital closed captioning features of a converter box is to record open-captioned programs to a TiVo or other recording device. TiVo has provided a free program, TiVo Desktop, to transfer recordings to a computer, but I've never been able to access the recordings because there were never any provisions made for decoding the captions in the program. With a CECB that can "open caption" programming that can then be recorded by the TiVo, however, that problem can be circumvented.

Right now, it's not easy to set up the TiVo for recording from a CECB, but there's a work-around.

At this time, people who use the older series 2 TiVos hope that the company will develop the capability to operate the converter boxes through the IR extender just like they have for the set-top boxes used for cable and satellite TV. TiVo is already providing the menu for recording digital signals for their HD boxes, so it shouldn't be difficult to allow the Series 2 boxes to utilize those existing menus. If TiVo would provide that menu, it would be a big help, but that's probably a ways away.

In the meantime, although I'm only using an antenna to receive television signals, I've used the TiVo Guided Setup to set up my TiVo box (Series 2) to use DirecTV AND antenna; this allows me to force the TiVo to go into a tunerless or "monitor" mode in order to use the output from the set top box (which is actually the converter box) while also giving me the option to record directly from the antenna for unattended recordings. This is just a temporary work-around but allows me to use the TiVo to record digital channels that don't have good analog reception, or an analog equivalent (like multicast channels).

The RF cable from the antenna goes straight into the RF input of the TiVo while the converter box's composite video and analog cables go into the equivalent input area for the TiVo (taking the place of the virtual set-top box for the phantom satellite service). (As far as I know, no set-top box is compatible with the converter boxes, so it doesn't matter which one is selected.)

It's necessary to delete lots and lots of satellite channels that you don't receive, but to keep the HD channels that correspond to local channels. I wound up getting double channels (one for antenna and one for "satellite") that are going to be confusing at first but which will provide guide information later on for the TiVo. (For example, the second duplicate channel will be for the "monitor" setting for the Tivo, which allows it to use the converter box. The CECB will have to be tuned to the correct channel by using the converter box's remote control.) If the quality of the reception for a particular analog channel is good, however, you can eliminate most of the duplicate channels for unneeded use of the converter box, and only leave duplicate channels for the channels that come in best via the converter box. (I kept HD channels for channels like 22 and 26 as there are several subchannels for those stations.)

Some of the multicast digital channels won't have any guide information at all provided by the analog TiVos, so some of the recordings for those channels won't be correctly described, and that will undoubtedly be confusing. We'll just have to wait for the TiVo company to change this situation, if ever.

But for now, this is a way to use a converter box to send a good signal to a TiVo that can be recorded, and one can choose whether or not to turn on the digital captions for an open-captioned recording. I'm thinking I might try to record open-captioned songs, for example, which I could then choose to transfer to my computer. (I enjoy music but my hearing loss is such that I can never understand the lyrics and usually have no idea about the meaning of a song.) I might also record open-captioned home improvement shows so I can refer to them later when doing a related project.

(The best way to do open-captioned recordings would be with a CECB that has an S-video output (the TiVo has an S-video input). So far, only the MaxMedia CECB appears to have both S-video output and digital closed captioning.)

Dana
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