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CC decoder
https://forum.lddb.com/viewtopic.php?f=50&t=224		 Page 1 of 2
Author:  naiaru [ 25 Oct 2011, 03:32 ]
Post subject:  CC decoder
Sorry if this is in the wrong section

Will a CC decoder degrade video quality? Also, are the captions adjustable (like changing font color, background size, etc.)?
Author:  publius [ 25 Oct 2011, 04:02 ]
Post subject:  Re: CC decoder
It depends on the decoder.

Some have adjustments of one kind or another, while others are very dumb. You can't insert characters into a video stream without affecting it somewhat, but a well-designed caption decoder will touch it as little as possible. An pure analog path using a simple character generator IC is probably the lowest-impact kind of manipulation there is.
Author:  naiaru [ 25 Oct 2011, 04:32 ]
Post subject:  Re: CC decoder
So how do I tell if a CC decoder uses a pure analog path with a simple character generator IC?

Also, if there are no captions present in the signal, will the CC decoder still affect image quality?
Author:  sonter [ 25 Oct 2011, 15:28 ]
Post subject:  Re: CC decoder
Im also interested in a CC decoder, can anyone recommend a good one ?
Author:  naiaru [ 30 Oct 2011, 23:59 ]
Post subject:  Re: CC decoder
The only CC decoders I'm seeing on eBay that allow for caption adjustments are TeleCaption (particularly their "100", "4000" and "3000" models) decoders, but they only have RF inputs, if I use a RF to RCA adapter will it still degrade the video quality? (I'm assuming not since I'm not including any audio, but idk)
Author:  publius [ 31 Oct 2011, 00:14 ]
Post subject:  Re: CC decoder
naiaru wrote:
The only CC decoders I'm seeing on eBay that allow for caption adjustments are TeleCaption (particularly their "100", "4000" and "3000" models) decoders, but they only have RF inputs, if I use a RF to RCA adapter will it still degrade the video quality? (I'm assuming not since I'm not including any audio, but idk)

If the input is only RF, you will run into many problems, including quality degradation. Just think, you will need to modulate the signal onto a carrier wave, then demodulate it again. This is a step you do not want.
Author:  naiaru [ 31 Oct 2011, 01:01 ]
Post subject:  Re: CC decoder
publius wrote:
naiaru wrote:
The only CC decoders I'm seeing on eBay that allow for caption adjustments are TeleCaption (particularly their "100", "4000" and "3000" models) decoders, but they only have RF inputs, if I use a RF to RCA adapter will it still degrade the video quality? (I'm assuming not since I'm not including any audio, but idk)

If the input is only RF, you will run into many problems, including quality degradation. Just think, you will need to modulate the signal onto a carrier wave, then demodulate it again. This is a step you do not want.

hmm, so what should I be looking for? on eBay, a "closed caption decoder" search only gets me a bunch of RF only TeleCaption machines, a few APICC1101 units, and a few triple digit priced machines

EDIT: Also, does anyone know of any closed caption decoders that have composite inputs and allow for customized captions (such as changing colors, fonts, etc.)
Author:  elahrairrah [ 10 Nov 2011, 20:08 ]
Post subject:  Re: CC decoder
I was thinking of getting one of these decoders when my main display was a Mitsubishi 37" computer monitor, but then I switched to a 40" Sony WEGA HD-ready TV. Glad I did because the CC decoder in those WEGAs are very nice. The text is much smaller than what i normally see from CC on other TVs and set lower as well.
Author:  kris [ 11 Nov 2011, 16:19 ]
Post subject:  Re: CC decoder
I would like to know if every CC device is capable of displaying the caption for laserdiscs. I see the "older" models from Telecaption on ebay at very low cost but indeed they only use rf in and outs.

Does the API CC-1101 work for laserdisc? they are so cheap these days so I was thinking of getting one as a spare unit...
It looks to be a basic caption decoder that is not oversized so...

The smallest available Is the Mycap Junior decoder with only composite in/out. sold it btw.

The best value for money would be the E-teck HQ-2000 has all in and outs plus customizable color/size/positioning/character caption menu
(it's very hard to find one these days) Currently I am using this unit, found it dead cheap nearby

Ligitek comes to mind.... can't remember the model

Futek .... say what? :o

Owned a few other "brands" in the past but until this day I have to see the first "good looking" unit
They all look so basic you would almost hide it out of sight in a system setup


Hope someone out there can advice on the API model question
Author:  publius [ 11 Nov 2011, 17:11 ]
Post subject:  Re: CC decoder
Closed Captions on LaserDisc are implemented exactly the same way as on broadcast NTSC. The only time there can ever be a problem, with any model of decoder, is during trick play operations. Of course, you have to match the inputs & outputs — ie, if the decoder only has RF in/out (ick), you will need a modulator/demodulator, whereas if it has composite (perhaps also S) in, you're set.

The API unit (manual here) should be fine. The only thing to observe is that you should only make the connexion you need, ie, connect via composite video & leave the RF (& audio) connectors alone. You might, if you're like me, cap off at least the RF input connector with a 75-ohm terminator, to avoid noise leakage into the unit. You will, of course, need a stepdown transformer delivering about 16 V AC.

The only problem I have ever had in this regard was when looking for a device which would allow me to feed a computer monitor from my LD player. I hunted high & low for a model with an integrated CC decoder, & wound up with a ViewSonic unit, only to find that (thanks to stupid firmware) decoding was only implemented on signals from the tuner input, not from the composite, S, or component inputs. But you will not encounter that with a stand-alone decoder.
Author:  elahrairrah [ 11 Nov 2011, 17:42 ]
Post subject:  Re: CC decoder
Aren't there some VCRs that would decode Closed Captions? Grabbing one of those used units would probably be cheaper than getting a standalone decoder with composite ins/outs.
Author:  publius [ 11 Nov 2011, 18:09 ]
Post subject:  Re: CC decoder
I don't know, I got mine for $10 or so in an electronic junk shop, missing its wall-wart. Picked up a suitable stepdown transformer for maybe $5, tinkered a little bit to match the power connectors, & Bob's your uncle.
Author:  nems [ 11 Nov 2011, 18:51 ]
Post subject:  Re: CC decoder
In a separate thread, LDDB member "rixrax" mentioned the upscaling Hitachi AVC08U. While checking out the specs, I noticed that it is also a "Closed Caption Decoder".

http://www.hitachi-america.us/supportingdocs/forhome/ubcg/ultrathin_1_5/Hitachi_AVC08U.pdf

http://www.epage.com/js/mi/c1064/b1064/r31118/3090275.html
Author:  publius [ 11 Nov 2011, 19:04 ]
Post subject:  Re: CC decoder
That's a standard feature for US TV tuners, which is what that Hitachi box is. As mentioned, occasionally one meets with a unit which isn't programmed to decode captions except through the tuner input, so you might ask him to test that.
Author:  laserbite34 [ 11 Nov 2011, 20:03 ]
Post subject:  Re: CC decoder
CC Yeah its a kinder subtitle used on DVD/bluray expect it needs an external box to extract the subtitles for hard of hearing on some laserdisc program content.

What do they normally sale for in the day and what is the reasonable going price for them today?

Is this to do with fact that PAL has limited encoding content like it can only hold one of the other analogue sound which was replaced with PCM digital yet NTSC can hold both and is this the case with CC it being able to hold more content over PAL?
Author:  publius [ 11 Nov 2011, 21:06 ]
Post subject:  Re: CC decoder
Closed Captioning is included in the video, in the "vertical blanking interval". It is similar to TeleText, but conveys less information, normally simple subtitles for the hearing-impared, plus time. (It is possible to have multiple caption channels, as for multiple languages, but this is less common.) Of course the time information is not needed on LD! Some PAL LDs do include TeleText subtitles, & LDDb does list one NTSC disc as well, although I have my doubts that the record is entirely correct here — analog audio only on a disc released in the 1990s?
Author:  laserbite34 [ 11 Nov 2011, 22:39 ]
Post subject:  Re: CC decoder
^^I have some of the PAL titles but when I looked at the title page the covers were different to the ones I have. Yes Tele-Text is common system in the UK for broadcast TV.
Cheers for the link publius
Author:  naiaru [ 15 Nov 2011, 04:34 ]
Post subject:  Re: CC decoder
So I just got that Hitachi AVC08U today from eBay.

It does decode CC from composite (haven't tried any of the other inputs yet), unfortunately it isn't customizable, but it doesn't look too bad. The black background looks a bit thinner than I'm used to and the text looks much smoother than it does with my TV's CC.

The scaling is a tad better than my TV's (definitely sharper and clearer). I'd say the scaling is at about DVD recorder quality.

The comb filter barely beat the one in my RCA DRC8335 (the Hitachi was slightly better when the pattern was moving).

It's only outputs are TOSLINK and HDMI (1080p60 or 1080i60)

Also, according to the Spears and Munsil disc, there's 26 pixels of overscan (with the composite and component 480i inputs anyways)

EDIT: Just tested running my LD player through a RCA DRC8335 (composite to component) and then through the Hitachi AVC08U.
The captions did appear, but with huge errors. They would loop lines over and over again, show the captions in flash, etc.
Admittedly this is the only test I've done of the AVC08U's component input, so I can't rule out that it's not just a problem with the RCA DRC8335
Author:  naiaru [ 22 Feb 2012, 04:27 ]
Post subject:  Re: CC decoder
elahrairrah wrote:
Aren't there some VCRs that would decode Closed Captions? Grabbing one of those used units would probably be cheaper than getting a standalone decoder with composite ins/outs.

Would you know of any models in particular?
Author:  elahrairrah [ 22 Feb 2012, 17:30 ]
Post subject:  Re: CC decoder
naiaru wrote:
Would you know of any models in particular?

Can't say for sure. I remember my first 4 head stereo VCR I bought back in 1993, an RCA model, could decode closed captions. But that VCR is long gone and I can't remember the model number.
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