HDTV-DVI Protocol Interpretation? 15
ignipotentis asks: "I have recently been looking into getting a Sony 50" Grand Wega. However, the one thing that deters me is the lack of obvious PC support. I would like to use the TV as a monitor for a living room PC as well as a TV. So I set off to do some investigation. I came across the ATI Component Adapters and then came across the reviews stating their overscan problems. Next I decided to check out the details on DVI (DVI & HDCP) and I've become rather confused. From what I gather, HDTV-DVI is nothing but DVI-D + HDCP. Now, being DVI-D, it can accept a signal from any DVI-I video card as long as a DVI-D male to male cable is used. Where I become confused is in the HDCP protocol. The way I read it, the Host (my computer) in this case, initiates the authenticity check whenever it wants. If it doesn't receive a valid reply, it can stop the stream. However, nothing is stated (that I can see) as to what would happen if no check was ever performed. If the Client (the TV) just continues to display what it receives, then all is good. If it does not, then I guess I'm back to the drawing board looking for other TVs. My question to Slashdot regards that of the protocol. I've emailed info@digital-cp.com only to getan automated response as a reply and I'm hoping that someone a bit more technically savvy than myself can interpret the HDCP protocol better than I have been able to."
The TV doesn't reject (Score:5, Informative)
I haven't tried looking for the right kind of cable -- I know there are different kinds of DVI connectors, and the TV's connector is likely different from what's on my video card. One of these days, I'll probably give it a shot.
BTW, I was surprised when I dug into the DVI spec -- it's nothing more than a digitized raster signal. I'd expected something a bit more structured, somehow, like (x,y,r,g,b) data. (though I didn't see anything about how HDCP worked).
It seems the real advantage of DVI over, say, an RGB/VGA connection, is that the pixel levels are exact-digital (as opposed to a varying voltage level) and the digital format (with error correction) is less prone to noise. Or am I missing something? Because unless it allows for direct mapping of pixels, I don't see why DVI would be more precise for, say, an LCD panel, than a very clean VGA signal.
david.
Re:The TV doesn't reject (Score:2, Insightful)
With the clocked digital DVI signal, the intended value for each pixel can be determined exactly.
Re:The TV doesn't reject (Score:2)
Component video out.... (Score:1, Informative)
You can probably ignore the HDCP (Score:5, Informative)
There are better forums to ask this question, such as The AVS Forum [avsforum.com] and The Home Theater Forum [hometheaterforum.com]
The TV is fine (Score:5, Informative)
Just buy a 64Mb version of the 8500 (fairly cheap and falling fast) and one of these things here. [ati.com] And off you go to HDTV PC viewing.
That's not a bad investment next to a $4000 TV.
ACRONYM tag (Score:2, Insightful)
Re:ACRONYM tag (Score:1)
Link to the official specification (Score:3, Informative)
Of interest, also, may be Niels Ferguson's paper [macfergus.com]in which he details the cryptographic weaknesses in HDCP. Unfortunately, he won't publish the document due to fears of being prosecuted under the US DMCA.
HDCP (Score:1)
bob
Was in this same situation (Score:1)
I had my nice little ~2k tax return (I claim 2) burning a hole in my pocket, and decided on doing the same thing, Picked up a Wega, ATI's component video adapter, and an 8500 LE.
Of course, soon discovered that the component video adapter is not worth a cent(you can never see your entire desktop), and it often just doesn't plain work..
Looking into this furthur, I discovered something strange. The component video adapter was 2x the shipping and handling as some of ATI's larger videoCard bundle packages.. Mind you that the adapter is a small thing and came in a "letter" type box. It costs twice as much to ship and handle something twice as small? (when I tried to return it, they mentioned I would pay the shipping, and a small 'handling' fee. They also mentioned that yes the current drivers would not support most TV's, and that a future driver version would enable this) Of course that's also when they told me that with ATI, after 30 days, you pay for customer support. Bad driver/Hardware problem with your card, or anything else? $2.99 a minute(of course you wait the obligatory 10 minutes before you speak to someone).
I honestly felt a little extorted.....really felt like there was a little bit of a bad conspiracy..The component did not do what they said, and raised shipping and handling charges, so that if people did return it, they still came out in the black... (also the 30 day thing is atrocious, (This is a real quote)
ME:"You say that it probably won't work without the newer drivers, and the newer drivers ETA >30 days, so I'll have to pay you to help me get it working the first time?"
ATI Support Rep: "Unforunately, Yes".
I'll admit Iwandered right into a rant, but ATI has a history of bad drivers....Before Buying something from them, do a LOT of research.
YMMV, but I say stay away...