A Beginner’s Guide to How HD Works

Yesterday I explained why you should watch HDTV – here’s a little background on the technology itself. It is commonly known that HD has better resolution than SD (standard television) so the picture is simply better. However, just because you have an HDTV, that doesn’t mean you are watching HD programming. First of all, it’s important to remember that in order to view all available HD channels, you need an HD set top box, tuned to an HD channel on an HDTV. If you aren’t doing this, you aren’t really watching HD. The easiest way to connect your HDTV to the HD set top box is with an HDMI cable. One cable carries both the video and audio signals.

You may have noticed that some HD channels and programming looks better than others. CNET has a great article that explains in detail the differences between HD resolutions (i.e. 1080 vs. 720 vs. 480) and sources (i.e. Blu-ray, 1080 programming, 720 programming, DVD, standard programming, etc.). And what about those old movies you watch on HD channels? Since most were filmed using high quality film, a process called telecine is used to convert the original film to a digital format such as HD.

Now you’re probably wondering, “How does the HD signal get to my HDTV?” Time Warner Cable in Texas has two “head ends” (one in Dallas and one in San Antonio that act as backups to each other) which connect the other Texas markets via a fiber optic “ring”. Many of the local channels transmit content to the Time Warner Cable head ends via fiber optic and most other channels are transmitted via satellite. The signals are then sent via fiber optic to “nodes” which are usually right down the street from your house. Due to the higher resolution picture, each HD channel we deliver to your home uses the bandwidth of about 3 or 4 standard definition channels. We’ve been able to add more and more HD channels by using Switched Digital Video technology.

OK, so enough about the technicalities, let’s get back to enjoying HD programming on our HDTV’s! Anyone curious what is going to happen on Mad Men this week?

Categories: Content Delivery, Cool Stuff, Texas