HDMI: The non-standard standard

TVs and video equipment used to be very easy to connect: you'd take a SCART cable and plug one end into your video device and one end into your TV and it would all work. The standard, while hardly easy to connect, never changed and there was never any trouble where one bit of kit wouldn't work with another.

Then along came HDMI, which gave us a way to digitally connect our devices together. It seemed like a brilliant advance. Sadly, it suffers from exactly the same problems as all other digital devices: a confusing and bewildering away of versions and standards, which leaves manufacturers open to creating devices that are incompatible with each other.

HDMI should be as simple as plugging one simple cable that carries sound and picture in, but somehow manages to turn this into a long drawn-out nightmare if you've chosen kit that doesn't want to work with each other. Take PCs, for example. If I plug my PC into my LCD TV via HDMI and set the refresh rate to 50Hz (the standard for this country), DVDs judder when played; switch to 60Hz (the American standard) or 24Hz (the standard for films) and they play correctly. Yet, plug in a DVD or Blu-ray player via HDMI at 50Hz and all is well. So, two devices connected via the same cable produce two radically different results.

It would be easy to simply dismiss this problem as PCs being a bit rubbish and not outputting video correctly, but the pain of HDMI doesn't stop there. We had a recent situation at work where a brand-new Samsung Virgin V+ box wouldn't work with a brand-new Panasonic projector. After a few engineer visits, the conclusion was that as the projector didn't take sound the V+ got confused and refused to output anything. The fix: a specially-written software patch to get the HDMI port on the V+ box talking to the projector.

That's not the only problem we've had. At Shopper we use an HDMI splitter, which can distribute one playback device (a Blu-ray player in this case) to four televisions, so that we can compare quality side-by-side. That's all well and good, except we recently had one television that refused to work with this system and, by doing so, stopped all of the other TVs plugged into the splitter from working too. The strange thing was that unplugging the first TV would cause the other televisions to start working, only the audio track was suddenly out of synch.
The biggest problem there's ever been was when Sky launched its HD service. Anyone with a Pioneer plasma screen was at risk of severe damage, as using HDMI to connect to the Sky HD box could fry a chip on the television, requiring a new (expensive) circuit board to fix it. You definitely wouldn't get that kind of problem with SCART.

A lot of the problems seem to be down to the way that HDMI has been developed, going through several versions of the standard, all of which support newer features. In addition, HDMI was also developed to be more than just something that carried audio and video, it was also designed to offer copy protection with HDCP (high-bandwidth digital content protection).

The idea behind HDCP is that it can prevent unprotected high-definition audio and video from being produced, in turn stopping people from making a perfect copy of a movie by recording the output. It's a nice idea in theory, but why would you bother recording something in real-time? Surely (by surely, I mean, actually), the easiest way to copy HD content, such as from a Blu-ray disc is to break the encryption and rip it as fast as your computer will let you, using the countless tools that are easily available on the internet.

Finally, HDMI is designed to allow other signals to be sent over it, such as control signals to let you control all devices made by one manufacturer using just one remote. Great idea in practice, but why let extra junk be pumped over this connection? Surely, it's just going to lead to more problems.

HDMI's a great idea, but it really needs to be a carefully considered standard that all manufacturers have to closely adhere too, and it should only be there for transmitting audio and video, nothing else. Rather than updating the standard as we progress, why not simply make sure that everything that's needed is included in the original standard in the first place?