What is HDCP?

HDCP stands for High-Bandwidth Digital Content Protection. In short, it’s a method of Digital Rights Management (DRM) used to protect digital audio and video signals that are generally sent over DVI and HDMI cables.

The importance of HDCP has been downplayed until recently, because almost no content providers (this would include HD cable, HD-DVD, and Blu-Ray) have content protection enabled. These providers however, can enable HDCP protection at any time. This is something that you as consumers must pay attention to in order to safe-guard your equipment investments.

Why now? With high-definition content becoming more popular, it’s just a matter of time before the studios start protecting their media. HDCP is their chosen mechanism and it is part of the specifications for both HD-DVD and Blu-Ray. Both formats currently don’t have HDCP protection enabled so as not to hinder adoption. When they'll start protecting their media is something no one knows.

If HDCP is used and you don’t have compatible devices one of two things can happen:

• Nothing – you get a blank screen or an error message
• Automatic degradation – that’s right; your beautiful high-def picture and sound can be downgraded to standard TV quality or some other lower-than-optimal quality

LCDs and Plasmas

Anyone thinking of purchasing a brand new plasma or LCD television has little to worry about. All plasma and LCD TVs with HDMI connectors are HDCP compliant. With DVI connectors things aren’t so simple.

Just about any current plasma and LCD television with a DVI connector is HDCP compliant. Notice the emphasis on “current” and “television”.

With DVI-connected displays many of the older units were not HDCP compliant. This is either because the standard did not yet exist when the set was designed or the manufacturer didn’t consider support for the standard important at that time. Be wary if purchasing used gear. If the display is one to two years old there is a small chance that the set is not HDCP compliant. Older sets have a much higher chance of not being compliant. Make sure to do your homework if you’re considering buying used inventory.

“Televisions” was also emphasized because of LCD monitors (for computers). With the low cost of wide-screen LCD monitors it has become popular to purchase one for use as a low-cost display. Be wary because, even today, the number of manufacturers releasing HDCP compliant LCD monitors can be counted on one hand. I don’t know of a single HDCP compliant LCD monitor sold before this year.

Tip of the Iceberg

Let me briefly mention that HDCP isn’t just part of your display – it’s part of any digital device used in conjunction with HDCP content.

In order to watch an HDCP encrypted movie in full quality on a Blu-Ray device you need a Blu-Ray player that’s HDCP compliant (all are) and a TV that’s HDCP compliant.

If you’re running digital audio into your receiver, that receiver will also need to be HDCP compliant. Quality buffs using dedicated video scalers also need to ensure those devices are HDCP compliant. The same goes for home theater PC users – your video card needs to be HDCP compliant.

Yes, that’s right; anything the digital data touches has to be HDCP compliant or you face an undesirable outcome.

In the Digital Realm Only

So if the digital signal is so protected why not convert it into analog? After all, an analog component video cable can handle full resolution 1080i high-definition signals!

Well, HDCP has the “analog hole” covered as well. When an HDCP encrypted signal is converted from digital to analog, the analog output is treated as a non-HDCP compliant device… so your signal will automatically be downgraded, or potentially even discarded.

Conclusion

The folks in charge of HDCP have their bases covered. It’s only a matter of time before it comes into use so you also have to have your bases covered as well. As soon as the switch is flipped any non-HDCP compliant device is more-or-less an expensive door-stop.

-- Stan

Stan is the lead designer and founder of Binary Metal. Binary Metal is a leading-edge designer of control and automation software for homes, home theaters, and computer-based media systems.