HDMI, DVI and HDCP: Which is the best for me?

Buy an HDTV that supports HDCP or prepare to shake hands with the devil every time you use HDMI or DVI cables.

The reason I refer to HDCP as the devil is because HDCP is quite possibly one of the worst technologies in television because it sits at the altar of control of the way we watch digital programming. While HDCP’s intent is noble – to protect copyrighted material – the disruption it causes to law-abiding viewers is too significant to ignore.

What is HDCP?

HDCP stands for High-Bandwidth Digital Content Protection and was developed by Intel Corporation. It is nothing more than a security feature that requires compatibility between the sender and the receiver, such as the HD cable box and the TV. By compatibility, I mean the HDCP technology built into both devices.

Think of HDCP as a security license key like the one you would enter when installing a computer program. Only this security key is invisible to you and me, but not to your TV.

It works by encrypting a digital signal with a key that requires authentication of the sender and receiver of the product. If the authentication fails, then the signal fails, which means there is no picture on the TV screen.

You might be wondering, “Who wants the TV signal to fail? Isn’t the point of television to enjoy watching it?

One would think so, but HDCP is about money. The problem is that digital technology facilitates content piracy. Do you remember Napster? Have you heard of video pirates selling movies with their trench coat? This is the purpose of HDCP – not illegal reproduction.

It’s about copyright. It’s about selling content instead of giving it away. It’s no secret that the film industry is embracing HDCP over Blu-ray discs, while the TV industry has yet to get involved at this point. It is true that the television industry has its own share of problems with the implementation of digital television.

Where is HDCP?

It is essential that you understand that HDCP is a digital technology. As a result, it only works right now with DVI and HDMI cables. Hence the acronyms DVI/HDCP and HDMI/HDCP.

What is the IVC?

DVI was created by the Digital Display Working Group, which stands for Digital Visual Interface. It’s an older digital interface that has almost been superseded by HDMI in TVs, so I won’t spend much time on DVI/HDCP. Just know that if you have an HDTV with a DVI input then HDCP could become an issue at some point for you if it hasn’t already.

What is HDMI?

HDMI stands for High-Definition Multimedia Interface. It is a digital interface that you will use with your HDTV to get the best possible uncompressed digital picture. HDMI has great support from the film industry. It was created by some of the heavyweights in the consumer electronics industry: Hitachi, Matsushita, Philips, Silicon Image, Sony, Thomson, and Toshiba.

There are two significant advantages of HDMI over DVI:

  1. HDMI sends the audio and video signal in a single cable. DVI only transfers video, so a separate audio cable is required.
  2. HDMI is significantly faster than DVI, which means more information transferred to your TV screen.

About.com Guide to Home Technology, Robert Silva, has a wonderful explanation of the differences between each HDMI version.

HDCP Buying Tips

Buy an HDTV set that has HDCP capabilities. Most will have it on at least one HDMI input, but you’ll certainly check that out before you buy the TV.

Notice I wrote, “at least in one port.” Not all HDMI ports on your TV support HDCP, so be sure to read your TV’s user manual if you plan to connect an HDMI cable to your TV.

There is no firmware update that can convert a non-HDCP input to an HDCP-compliant input. If you bought an HDTV a few years ago then there is a great chance that you will get an HDCP error when connecting a Blu-ray Disc player to your HDTV with HDMI. This would force you to use non-digital cable, buy a new HDTV, or ditch the Blu-ray Disc player.