[Gary Merson]

DVI is the digital input of choice for digital computer displays such as industrial plasma and LCD monitors (many also do a fine job displaying HDTV) This application is a perfect use for a DVI input as it was originally designed for precisely this application, as a cost effective way to provide a digital path from source box (PC) to a computer display device.


There are many of these displays on the market or coming soon and most do not contain HDCP. This includes the new Zenith 30" & 17" Wide screen HD LCD displays. DVI si, HDCP no.


Zenith's upcoming DirecTv STB does have DVI/HDCP. The reason is simple. DirecTv is requiring it on all new HD set top boxes. It also has component and RGB analog outputs.

 

[Cambridge Bob]

Gary,


Thanks for your effort to provide some accurate information. However, I would dispute the assertion that "most do not contain HDCP." I would be shocked if any do not license HDCP.


I would hope that, by now, most AVS Forum readers are aware that the sole purpose of HDCP is to prevent anyone from recording the DVI signal. However, since there are no consumer devices to record a DVI signal (they would be very expensive to produce), nothing of any practical value is taken away. One legitimate concern about DVI/HDCP is that it will become the exclusive display connector -- i.e. that DVI/HDCP will required for viewing primo content. There are also legitimate concerns about the whole licensing & encryption-based copy control system, of which HDCP is a small part. The focus of this concern should be the satellite and cable licenses (PHILA) and, secondarily, DTCP. Unlike HDCP, the cable license is not finalized and public input may have an effect.

 

[Gary Merson]

Bob,


This was not meant as a prediction of future implementation of HDCP, just a clarification that buying a DVI display does not give the purchaser an assurance that it will have a copy protected input.


The whole subject of copy protection and what it will and will not do is still in flux.


We are in the smack in the middle of a unique part of the digital era, when new laws, industry and govt. decisions will determine the way will be able to enjoy (and pay for) the home entertainment experience for the future.


The loss of the control of content by the home user may cause the outright extinction of free HD home recording or a complete change in the utility of of some very exciting present and future products such as PVRs, HD PVRs, HD-DVDs and others.

 

[onemoretime]

I say let the studios keep their HD products to themselves, if that is needed to avoid HDCP. I think they might even find that the risk (mitigated by cost of removable digital media and their recording devices, speed of the internet, and use of simpler copy controls) is worth the reward - look at DVD's. But that's their choice, they don't push it on us.

 

[Cambridge Bob]

Look at DVDs, then. They are encrypted (next time, the encryption is going to be a wee bit harder to crack). DVD players have analog outputs that are protected by Macrovision and associated acts of Congress. Meanwhile, displays are gradually going digital. Enter DVI/HDCP. Now DVD players can go digital to the display without exposing the signal to direct digital recording (i.e. HDCP serves the same function as Macrovision). Who cares if you can't record DVDs? - not the average person.


Gary, I now see what you meant. I was thinking about the "coming soon" displays, virtually all of which use HDCP on their DVI inputs.


I'd say the copy protection issue is in flux at a high level. It's clear the DVI/HDCP (the lowest level) is ready to hit the streets. It's clear that DVI/HDCP and firewire/DTCP have their places - though it's not quite clear if a display with only firewire input will be well-supported. Watermarking schemes are being reviewed for use on analog outputs (to address the analog security problem and provide backward compatibility for existing analog-in displays). I still sense reluctance among some content providers to accept the encoding rules of DTCP, which pretty much limit the heavy-duty copy protection to PPV and the like. (There is good wisdom and hard-fought compromise in those rules, so I believe they'll have to be accepted in the end.) There are sundry issues with cable, satellite, PVRs. The biggest up in the air issue (by far) is the proposal to keep OTA broadcasts off the internet, which we'll hear more about on Friday.

 

[onemoretime]

Sorry, but HDCP is invoked by the program source. There is no regulation of this - it could be your friendly local weathercaster. You want to watch HDTV on your multi-kilobuck system? - then surely you can't object to a small toll to satisfy your want. Correct me if I'm wrong, but the FCC is mandating DTV to regain spectrum for other uses, not only HDTV, so you can wind up with a lot more SDTV channels, or GKW, and very few HDTV programs. HDCP is not about protection, it's about control


As I write this, I'm looking at an analog input LCD that is inherently a digital display, and wouldn't be any better for a DVI input. Guess what - CRT's run from "analog". The inevitability of DVI assumes CRT's die - - not!


BTW, a lot of broadcasters put their content on the internet now.


The word collaborator (someone who has, charitably, been sucked in) occurs to me when I hear that the overweening control proposed by the BPDG CP scheme is OK. I'm sorry if I'm over-reacting and misinterpreting some views. We can rationalize any wrong in this world, but we shouldn't rationalize something inherently wrong, that hasn't even happened yet. HDCP gives content providers absolute control over your use of their content and as well as your use of your hardware. The greatest wrong is they, particularly the studios, don't need it to make gigabucks.

 

[Gary McCoy]

One small correction - the analog TV spectrum has already been sold to various wireless services. The "Great Spectrum Giveaway" scandal in WJ Clinton's first term in office was actually an auction. The analog spectrum now belongs to whomever gave more $ to assorted Senabores and Congress Critters and of course Al Gore's 2000 presidential campaign. Come the magic date in 2006, we'll either find out who those anonomous folks were, or those wireless services lobbyists will find out those politicians didn't stay bought in the face of a grassroots campaign to "Save our TV sets!".


It should be entertaining to watch.


Gary

 

[Cambridge Bob]

Gary started this thread with some reasonably accurate information. I tried to continue in that spirit. Oh, well.


onemoretime,

When you use words like "inherently wrong" and "absolute control" and "collaborator" it is clear you're coming from the Ministry of Hysterical Ramblings and Paranoid Delusions. At least you admit you might be over-reacting and misinterpreting. Maybe there's hope for you yet.


Let's try not to get too far away from the facts.


Fact: HDCP is not always invoked by the program source. It depends on the upstream license, if any. For example, a DVD player would always use HDCP on its DVI output because the source (DVD) does not contain copy control information. In contrast, an OTA receiver would never use HDCP (assuming BPDG fails to get its way).


Fact: Reasonable standards for copy control are suggested in the DTCP license. There is no government regulation, but there doesn't need to be. Like any other consumer electronics product, if the design isn't right, people won't buy it.


Fact: LCDs with digital inputs are superior to LCDs with analog inputs. The image is sharper, clearer, more stable, less noisy.


Fact: Digital displays (LCD, Plasma, DLP) are decreasing in price by about 50% every two years. Significant advances are in the pipeline. Digital displays already account for a large percentage of new computer monitors. Digital displays use less power, they're lighter, they're thinner and in the long run, they tend to have fewer quality control problems. It's only a matter of time before manufacturers start dropping CRT-based displays from their lines.


Fact: Nobody here said the BPDG CP scheme was OK. Personally, I have thoroughly ridiculed it in other topics. No need to repeat that here.


Fact: HDCP prevents recording of a DVI output, in the highly unlikely event that anyone would be crazy enough to develop a HD recorder with a DVI input. Beyond that, you can't really say that HDCP does anything.


Consider this analogy: Does Macrovision give content providers absolute control over your use of SD content and hardware? If not, please explain why you think HDCP is substantially different in its purpose and scope.

 

[kelliot]

Quote:

Look at DVDs, then. They are encrypted (next time, the encryption is going to be a wee bit harder to crack). DVD players have analog outputs that are protected by Macrovision and associated acts of Congress. Meanwhile, displays are gradually going digital. Enter DVI/HDCP. Now DVD players can go digital to the display without exposing the signal to direct digital recording (i.e. HDCP serves the same function as Macrovision). Who cares if you can't record DVDs? - not the average person.

My guess is that it will take ~5-10 years for digital displays to penetrate to meaningful levels and that until then, they will have dual analog/digital outputs.


There is too much revenue being generated to publish a huge amount of material that can't be played on anlog outpust of conventional DVD players.


The bottom line: We won't see DVI/HDCP in volume until HD-DVD comes to market.

 

[onemoretime]

CB, obviously you and Gary are closer to this than some of us, so you can help me understand it better.


But first I didn't create the MHR&PD - it was the studios with their mythical wholesale piracy of HD content over the internet. Yes, it may be technically possible someday, but is it any more of a problem than piracy of DVD's today? If internet piracy of DVD's is causing the downfall of Hollywood, then I admit I'm wrong, or tell me otherwise why we shouldn't be paranoid while they plan to lock up our equipment and software.


I guess you agree that OTA should not use HDCP, and that BPDG should not get their way on this.


I'm sure there is reasonable copy/content control, as defined by the content owner, but I don't know if I would find it reasonable. Is there a section in the license that I should read again?


No doubt digital display devices are better served with DVI, but I want to keep my analog chain as is, thank you. DVI is also a protection scheme as you have pointed out. So why can't I have analog forever? It does not provide an exact digital copy. A secure digital link between the tuner and a recorder (which I may not buy, hence not need DVI) should not void analog for the rest of the system. The only reason I can see to put CP in the whole chain is to control every aspect of content.


As I understand it, macrovision prevents good copies of tapes. I also understand it is easily defeated. HDCP will not be limited to pre-recorded material (as far as I know); it is not easily defeated, and if it is, equipment is disabled and new schemes/equipment will likely be foisted on us.


I apologize if it seemed I was attacking your posts. I am attacking any hint of suggestion that what is going on is reasonable, rational or acceptable. I know, a lot of people smarter, richer and more handsome than me are going along with HDCP.


No doubt the work of the BPWG is technically sound, and that it includes respected manufacturers and broadcasters. There must be some degree of Stockholm syndrome to make some of them side with MPAA rather than their consumers. They shouldn't be afraid to walk away - they are not co-opted until they agree.

 

[sawyer]

GARY and/or BOB:


Since DVI was brought up, I would like to ask a few questions that I think are on everyone's mind for clarification:


1) When you say "DVI" input on these new HDTVs do you mean:


DVI-A (analog)

DVI-D (digital) dual link,

DVI-D (digital) single link,

DVI-I (analog & digital) dual link or

DVI-I (analog & digital) single link?


Will all DVI inputs on HDTVs be the same or different versions as mentioned above?


2) Will these DVI inputs be the same as what PC projectors have been using for years, and if not, what is the intercompatiblity of the three (five total) different types of DVI mediums?


3) Will DVI connections that are HDCP compatible also be compatible with HDMI (high definition multimedia interface) copy protection? or will this require a different medium?


4) 2 issues ago, Home Theater magazine tested a new HDTV (I think a Sony) with DVI inputs and stated that the same signal on the same sized HDTV with component inputs was not as sharp as the one carrying a DVI signal. Is this because DVI has a bandwith capacity of 360 Mhtz and allows more dynamic headroom of the video signal? (even when it is 1920 x 1080i (or 1280 x 720p) on BOTH?) or because there is never a conversion to analog to digital and then back?


This does make the investment in a DVI compatible HDTV worthwhile, if in fact it is true.


The huxian rep mentioned in a previous post that if you plan to use 1920 x 1080p resolution, 360 MHtz of bandwith will be required, which only the DVI-I has the capacity to carry. Another reason to make sure the format is DVI-D or DVI-I.


5) What is the format of DVI output on a Radeon video card, and how does this compare in format to the DVI output from the new STBs that you mention?


Gary, you briefly discussed DVI on page 18 in TPV issue #39, but didn't mention the technical specifications (bandwidth) and the three different formats mentioned above.


Any clarification much appreciated.

 

[onemoretime]

Ooops - in re-reading my post, it seems aggressive. I intend to aggressively approach the topic of HDCP and not persons. No offense intended. The curse of e-mail applies here too. Sawyer's post is a logical continuation of this thread.

 

[Cambridge Bob]

Quote:

Originally posted by sawyer 1) When you say "DVI" input on these new HDTVs do you mean...

If this helps: "Interoperability. Licensed Products shall be constructed to support full interoperability by fully implementing all mandatory aspects of the Digital Visual Interface (DVI) Revision 1.0, April 2, 1999 (or such later version as may be in effect at the time of Adopter’s design of the Licensed Products) with the exception of those expressly identified as optional or informative. Licensed Products and Licensed Source Components shall not apply HDCP encryption to Video Content transmitted to outputs other than DVI outputs. HDCP shall not be implemented in any Licensed Product or Licensed Source Component in a manner so as to cause such Licensed Product or any Licensed Product incorporating such Licensed Source Component to be non-interoperable with other Licensed Products."
Quote:

Originally posted by sawyer 2) Will these DVI inputs be the same as what PC projectors have been using for years, and if not, what is the intercompatiblity of the three (five total) different types of DVI mediums?

Legally, it's governed by licenses we can't get our hands on. HDCP does not prohibit this. DTCP allows it, more or less, as long as the image is constrained when and if directed. But the key is the source device's governing license, which is proprietary in the case of D-Theater or satellite companies. Technically, I have no idea whether or not its feasible.
Quote:

Originally posted by sawyer 3) Will DVI connections that are HDCP compatible also be compatible with HDMI (high definition multimedia interface) copy protection? or will this require a different medium?

Yes. Definitely! A cable adapter (or special cable) is required.
Quote:

Originally posted by sawyer 4) 2 issues ago, Home Theater magazine tested a new HDTV (I think a Sony) with DVI inputs and stated that the same signal on the same sized HDTV with component inputs was not as sharp as the one carrying a DVI signal. Is this because DVI has a bandwith capacity of 360 Mhtz and allows more dynamic headroom of the video signal? (even when it is 1920 x 1080i (or 1280 x 720p) on BOTH?) or because there is never a conversion to analog to digital and then back?

Thanks for pointing me to that article. This seems to verify what I've been telling people all along - that digital transmission will aid even tube-based sets. It eliminates noise from the transmission along with the need for the display to filter noise. The display can perform scaling (if necessary) and do graphic overlay in the digital domain. The final conversion to analog can be customized for the tubes. Basically, the relative lack of analog processing means less additional noise. Furthermore, all analog circuitry is in the same box, under a single designer's control. Personally, I plan to get a 32" Sony with DVI/HDCP as soon as it is available - next month, hopefully.
Quote:

Originally posted by sawyer 5) What is the format of DVI output on a Radeon video card, and how does this compare in format to the DVI output from the new STBs that you mention?

Sorry. I'm more of a software guy than a hardware guy.

 

[Cambridge Bob]

onemoretime,


Here is an excerpt from the DTCP spec, showing the relatively reasonable encoding requirement I referred to in a previous message.
Quote:

2.1 Encoding Rules. Adopter acknowledges that Content Participants may only encode Commercial Audiovisual Content using DTCP to prevent or limit copying as set out Sections 2.1.1 and 2.1.2. 2.1.1 Copy Never. Commercial Audiovisual Content delivered as follows may be encoded and transmitted as Copy Never Content: 2.1.1.1 Prerecorded Media, 2.1.1.2 Pay-Per-View, 2.1.1.3 Subscription-On-Demand, 2.1.1.4 Video-on-Demand, 2.1.1.5 New business models that are comparable to 2.1.1.1 - 2.1.1.4. 2.1.2 Copy One Generation. Commercial Audiovisual Content delivered as follows may be encoded and transmitted as Copy One Generation Content: 2.1.2.1 Prerecorded Media, 2.1.2.2 Pay-Per-View, 2.1.2.3 Subscription-On-Demand, 2.1.2.4 Video-on-Demand, 2.1.2.5 Pay Television Transmission, 2.1.2.6 Non-Premium Subscription Television, 2.1.2.7 Free Conditional Access Delivery, 2.1.2.8 New business models that are comparable to 2.1.2.1 - 2.1.2.7. 2.1.3 No More Copies. Licensed Products shall only encode as "No More Copies" content received as Copy One Generation and stored via a method set out in, or approved pursuant to, Exhibit B, Part 1, Section 2.2. 2.1.4 Encryption Plus Non-assertion Encoding. Adopter acknowledges that EPN Encoding may not be asserted by Content Participants with respect to EPN Eligible Non-Conditional Access Delivery, except by such eligible Content Participants that are identified by DTLA. “EPN Encoding†means such encoding used by or at the direction of a Content Participant so as to cause a service or Program to be encrypted with DTCP but not to be subject to copy control restrictions. 2.2 Image Constraint. Adopter acknowledges that Content Participants are not permitted to encode, or direct to be encoded, Commercial Audiovisual Content so as to require Decrypted DT Data to be output as a Constrained Image except with respect to Prerecorded Media, Pay Television Transmission, Video-on-Demand, Subscription-on-Demand, Pay-Per-View, a new business model comparable to any of the foregoing or any other Conditional Access Delivery of a Program that (i) had a theatrical release or was released direct-to-video and (ii) is transmitted or delivered uninterrupted by Commercial Advertising Messages. Licensed Products that have a Source Function (a “Source Deviceâ€) shall set, in accordance with the Specification, the Image Constraint Token associated with a Program so as to permit any Licensed Product with a Sink Function to output such Program in High Definition Analog Form if such Source Device outputs such Program in unprotected High Definition Analog Form other than as permitted in Section 4.3.3 of Part 1 of Exhibit B. In addition, a Source Device shall set, in accordance with the Specification, the Image Constraint Token associated with a Program so as to permit any Licensed Product with a Sink Function to output such Program in High Definition Analog Form if such Program was not specifically encoded to output such Program as a Constrained Image when received by the Source Device.

I know, it's hard to read legalese. Basically "copy never" = PPV or pre-recorded media = image constraint on unsecure outputs. If the content providers agree to DTCP, that's the worst case. The oddball is "Pay Television Transmission," which includes HBO. They are required to allow at least one generation recording. However, they could use image constraint (not that they would any time soon).

 

[onemoretime]

Thanks. I do find it hard to say it has merit, when I strongly oppose CP. It solves someone else's paranoia, and triggers mine - which I take very personally. It can be implemented in a changing, unfriendly way. I hope there are less intrusive solutions, and this is deep-sixed. As I understand it, federal regulation won't be needed, (nor its well established process) since the standards will be supported directly by legislation. No manufacturer can put anything in the pipeline that doesn't properly handle protected content, licensed or not. Not much if anything left to the marketplace.