Thursday, March 15, 2007

WHAT IS HDCP?

You may heard the term Digital Rights Management or DRM recently. Well HDCP is a form of DRM. In an attempt to prevent users of high definition equipment from copying or displaying copied content, Intel came up with HDCP: HIGH BANDWIDTH DIGITAL CONTENT PROTECTION. HDCP is backed by the Motion Picture Association of America (MPAA), and so all new digital content from the movie studios is likely to include this protection. In its simplist form, the two hdcp devices, lets say the hdtv and the blu ray player, are trying to communicate. The blu ray player says to the tv that it wants to send some HD content to it, and lets it know that its secured with hdcp. The tv confirms that it is ALSO secured with hdcp. Both devices exchange a set of security keys until they're both happy. The result, you get HD content on screen.

If you're using blu ray, hd dvd, a satellite receiver, or any other DIGITAL source and viewing the content on an hdtv, both devices have to be "HDCP compliant." If only one device is compliant, you'll have issues, or maybe no picture at all. The older hdtv's are not hdcp compliant, and takes us back to the issue of early adopters being left in the dust. Again, this compliance issue only pertain to digital devices, so you have to be using a digital cable. Anyway, lets get to the scenarios so we can understand this better:

  • hdtv IS HDCP compliant, blu ray/hd-dvd player/satellite receiver using a digital cable IS NOT HDCP" compliant: The picture will be limited to standard defintion of 540p with hdcp compliant material.
  • hdtv IS HDCP compliant, blu ray/hd-dvd player/satellite receiver using an analog cable IS NOT HDCP" compliant: The picture will be limited to standard defintion of 540p with hdcp compliant material.
  • hdtv IS NOT HDCP compliant, but the source(player/receiver) IS: Blank Screen.
  • Using an analog and NOT a DVI or HDMI digital cable: The picture will be limited to standard defintion of 540p with hdcp compliant material.

This constaining of HD resolution to 540p is done by an "Image Constraint Token" or ICT. This is currently left to the discretion of the movie studios on what they do with each movie they release. They have agreed not to "flag" any blu ray or hd dvd movies in the near future with ICT because the studios acknowledge that it would leave a lot of current high definition consumers with either standard defintion resolutions or blank screens.

I should point out that everything is still in the process of being standardized. This is the reason why not all devices and displays you buy today have HDCP. But it is becoming increasingly more prevalent, and inevitably looks like if you're home theatre devices don't have it, you could be left behind. The xbox 360 for example, currently outputs a 1080i signal for its games and HD-DVD movies using an analog component cable. If the movie studios decided to implement HDCP in all their content and made it a complete standard, then future HD-DVD movies on the Xbox 360 would be limited to a 540p resolution!

The bottom line is, HDCP requires all your devices to be "HDCP compliant" and to use a digital cable such as DVI or HDMI to guarantee absolute compatibility. At the moment, we're still in a transition phase where manufacturers, the FCC and the MPAA are "accomodating" consumers. If they pull this plug on us now, satellite companies for example will lose 80% of their subscribers, as most use analog component cables to get a 1080i signal to their hdtv. So in place of this, they're lying low. But as time goes on, things could change drastically!


3 Comments:

Peter Chen said...

Hi Triniman,

Thanks for leaving a comment in my post How to get rid of borders from images uploaded via the photo upload icon in the Blogger post editor toolbar. I have responded to your comment.

Peter
Dummies Guide to Google Blogger

Peter Chen said...

Hi Triniman,

Just dropping by to let you know I have responded to your second comment in the post How to get rid of borders uploaded via the photo upload icon in the Blogger post editor toolbar.

Peter a.k.a. enviroman
Enviroman Says

BarbiDoll said...

I finally get it. I checked, and my lcd IS HDCP compliant. Thank you so much for all this great information!