Recent Posts

Friday, July 6, 2007

Pain in the Aspect Ratio! Why Do I Still Have Black Bars On My HDTV?

The consumer electronics manufacturers and motion picture industry have teamed up to bring you a point of confusion regarding aspect ratios and the simple task of watching TV. Black bars and stretched images due to mismatched aspect ratios give unexpected results for new TV buyers. Laced with many new benefits, the High Definition Television (HDTV) standards brought us three new features: (1) higher resolution pictures that provide greater detail, (2) surround sound output that can be directed to multiple speakers, and (3) a new aspect ratio for the screen. It is the "strange but true" topic of the aspect ratio that has brought confusion and is addressed here.

First of all, the aspect ratio is not the size of one’s buttocks in relation to one’s overall height (in the sense that Jennifer Lopez would have a higher aspect ratio than Paris Hilton), but rather the relationship of your TV’s width to its height. The standard aspect ratio that has been used on TVs since their inception has now changed with the new HDTV standards. Original TVs had a 4:3 aspect ratio, which means for every 4 inches wide, they are 3 inches tall. This gives the appearance of a rectangle that is almost as tall as it is wide – close to a square. This ratio may also be written with reference to a single unit of height, or 1.33:1 (4 divided by 3 = 1.33). In contrast, the new HDTV standard uses a 16:9 aspect ratio or 16 inches of width for every 9 inches of height. This ratio, also known as 1.78:1, is much broader and is referenced as a widescreen format.

The reason for the move to the wider screen is to provide a much more theater-like experience. Back in the 1950s, the motion picture studios were fearful of television’s ability to erode the attendance at movie theaters (Sound familiar? Now HDTVs are further eroding theater attendence). In response, the studios changed the aspect ratio on movies from 4:3 to a much wider stance. This allowed movie-goers to feel much more immersed. It is not until recently that a wider aspect ratio has been brought to the home. Now, thanks to HDTV, we have the widescreen 16:9 format. Peculiar enough, however, is the fact that the 16:9 ratio is unlike anything produced by movie studios. Hmmm. Will this cause problems?

According to a Consumer Electronics Association (CEA) study released in April 2007, about 28% of U.S. households have HDTVs (see TVweek.com). Despite this growing number, only a small percentage of channels available on cable and satellite provide HD programs. A clear majority of the programming is still in standard definition with the original 4:3 aspect ratio. Most television content providers are showing less than 20 HD channels, often amounting to less than 10% of its programming. So if we must live with it, how do we display a 4:3 program on a 16:9 television? There are three basic ways to do this. The first method is to zoom the picture and crop the top and bottom. Be careful, though, because close ups can give Clint Eastwood a flattop. The second method is to s-t-r-e-t-c-h the picture to fill the screen. This is what makes Brad Pitt look like Jack Black (see post on non-HD content on HDTVs). Lastly, you can maintain the full image and 4:3 aspect ratio by showing black bars at the side. This is called a pillarbox effect. For those concerned about preserving the original image without distortion, pillarboxing is the best alternative.

So it would appear that we have this aspect ratio thing understood. Now I can go out and spend $5,000 on a 50-inch HDTV for my bathroom. Since I usually watch movies from my bathtub (I call it my “pruning” time), I’ll also plan to hook up a DVD player to it. This will allow me to show widescreen movies on my widescreen TV: a perfect match. I will purchase G.I. Jane, featuring the best bald-headed chick since Ripley in Aliens 3, and pop it into the player. To my surprise, I will not have escaped the annoying black bars. The bars have merely rotated ninety degrees and pushed themselves to the top and bottom. What the…? Does this TV need to go back to the manufacturer? Not so fast.

The movie G.I. Jane is presented in a 2.35:1 theatrical aspect ratio. The motion picture industry now has a few different standards, many of which are even wider than 16:9. The 1.85:1 ratio is another popular ratio for movies, but much closer to our TV’s 16:9 ratio. When you display a video with an aspect ratio wider than 16:9, you get black bars at the top and bottom, giving a letterbox display. So let's review. We have a 1.33:1 standard aspect ratio (aka 4:3), a 1.78:1 HDTV widescreen ratio (aka 16:9) and several theatrical aspect ratios such as 1.85:1 and 2.35:1. Whew!

Now here’s the bad news. When you have a 16:9 widescreen TV and display a standard definition program in 4:3, the black bars on the side mean that 25% of the screen you recently purchased goes unused. When you watch a movie filmed in the 2.35:1 ratio, the black bars are at the top and bottom, but again 25% of the screen is always black. The 1.85:1 ratio is the closest to 16:9 and translates into a mere 4% loss. Those other numbers are pretty big, though. This is like buying a car that can only use three tires on most roads? It’s the price we all pay for the variety of aspect ratios out there. Now you know why I consider this topic a “pain in the aspect ratio!”

Despite all of this complexity surrounding aspect ratios, the HDTV standards do bring many benefits to those who upgrade their equipment. In the near future, high definition 16:9 programs will be prevalent among the viewing options. We will eventually be much happier as we use 100% of our television screen and Brad Pitt will look like…well…Brad Pitt. Then the only worry we have left is watching our dessert consumption so we don’t increase our own body’s aspect ratio. The last thing we want is to develop a personal widescreen format. A pillarbox shirt is not slimming.

[Note: This is a revised version of the original post, 5/3/07]

No comments: