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There's No Such Thing as 'Wireless HDMI'
An anonymous reader writes "CE Pro magazine interviewed Steve Venuti and Les Chard of HDMI Licensing, LLC to get a preview of all things HDMI at CES. The duo addressed some of the more controversial issues surrounding HDMI, including 'Wireless HDMI' (There's no such thing); Consumer Electronics Control (There will be interoperability); competitor DisplayPort (No traction in CE); and the complications of HDMI ('It is not an HDMI problem. It's a digital issue.')"
HDMI is only a link-level protocol, electrical, cable and plug/jack specification much like 100BaseTX. HDCP is the actual DRM introduced along with HDMI and it has been adopted by both DVI and DisplayPort.
HDCP (be it over HDMI, DVI or DisplayPort) is only required for playing back DRM-infested media at full resolution on DRM-infested OSes like Vista.
HDMI is DVI video + digital audio + a DRM system called HDCP (High-bandwidth digital copy protection). HDMI cables have a different pin-out than traditional DVI connectors, but there are adapters that can take one to the other. The DRM system is not required unless the media requires it (more on this below). So, for example, I have my home theater PC connected to my HDTV via a DVI->HDMI cable, and it works just fine. The digital audio on HDMI has the ability to transmit faster than the old S/PDIF system, but other than that it's pretty straight forward.
The HDCP DRM functions by way of a system called the image constraint token. You can plug an HD-DVD or blu-ray player into a tv via analog component (RGB), but the manufacturers of those discs have the ability to activate the image constraint system on the disc if they wish. Unless the player reports that it's connected via HDMI (and thus has the ability to encrypt the signal), the output resolution on the video is reduced to 1/4th the original (960x540 vs. 1920x1080). As far as I know, no disc currently shipping implements the constraint token, and the studios stated that they planned to hold off on activating it until 2009.
In the computer world, the OS as well as your computer hardware has to support the system if you want to playback video that requires HDCP encryption for full resolution. Many video card manufacturers are currently shipping cards with DVI that has HDCP capability, but you'll need Vista to enable it as far as I know. You'll also need a monitor or television with HDCP support. This usually means purchasing a monitor with HDMI inputs, but there are many that use DVI and support HDCP over DVI. One manufacturer I know of, ASUS, is currently shipping a mainboard based on the NForce chipset that has an HDMI output that actually combines the onboard video and audio into the single cable, but for everyone else you'll generally have to run the audio over coaxial or optical digital and the video over HDCP-eqipped DVI or an HDMI connection that isn't transmitting audio.
The comical part, of course, is that they've spent so much time locking down the video stream when it's far more likely that people will crack all of the DRM at the disc level. HD-DVD has already been mostly compromised, and Blu-Ray discs have an extra level of DRM that hasn't yet been implemented but is theoretically supported in all Blu-ray player. Of course, I'm sure it will be just as foolproof as all the other DRM systems...
At the end of the day, the principle complaint that people have with HDMI is that the need to handshake for encryption sometimes gets screwed up, especially when switching inputs. So, for example, most people who plug their PS3 straight into the TV do fine, but if you plug it into an audio receiver and plug the receiver into the TV, people may experience a blank screen when they switch back to the PS3 input because the system is convinced that the link has been broken. In this situation, you have to go unplug and replug the HDMI cable to re-establish the link and get your video signal back. Highly annoying, but nothing like the ridiculous "We're closing our online video store so your purchases are now worthless because they can no longer be authenticated." In my opinion, the benefits of the single cable digital audio+video outweigh the minor and occasional annoyance, although it sucks that the annoyance only exists because of the asinine requirement for DRM on the cable.
I have a 50' HDMI cable too. My components are in a cabinet in the front corner, and the TV is mounted on the back wall. Cable has to go down through the basement.
Here's the problem. When you go long, the cable diameter increases as the wire size increases. My cable is 1/2" in diameter. It doesn't bend well, and you can't do much of a bend by the connector due to stresses. This makes it a bitch to plug in to the set.
HDMI sucks. Pro gear doesn't use it, it uses a HD version of SDI which only uses coax cables and has a MUCH longer distance capability without repeaters. Love your HDMI all you want. I hate it with a passion.
I want optical. Optical is future proof and doesn't have a distance issue (within reason.) It uses standard connectors which are MUCH easier to terminate than they used to be. It isn't reasonable to terminate your own HDMI cables in any case, so concerns about termination are moot. Prebuilt optical cables over a certain length are less expensive than HDMI too. Thinner, better capacity, etc.
The HDMI folks can take their spec and shove it. Idiots.