A couple weeks ago I looked in depth at the different sound formats and technologies you will, or have already seen (or should I say heard?) in viewing your DVDs. This week I will take a look at the different ways video is presented in the format, what to look for, and what the differences are. We will look at Widescreen (1.85:1 and 2.35:1 and anamorphic), Full Screen (1.33:1) and Progressive Scan, and THX.
Full screen pictures are what most of the population has become accustomed too, as it is the most common form of TV size, and therefore most broadcast entertainment is presented in the 4:3 ratio, or 4 inches wide for every 3 inches tall (more simply 1.33:1). Most VHS movies were presented in this format as well. Yet, one must realize that this is not the way movies are presented in a theater; therefore, to get to this full screen ratio the producers must strategically crop the movies sides (a process known as pan-and-scan, or pan-and-scam for the people who dread the format) so that it fills the viewer’s standard TV. The main point here is that this is, for the most part, NOT the way (see Stanley Kubrick) the director wanted it viewed. Thankfully, for those that cannot stand black bars on their TV sets, most DVDs present the user with both options of viewing full screen or widescreen.
“Why are those black bars there?” Yes…Widescreen is just what you probably think it is, giving you a wider picture then you are used to, and in return, your television (non-widescreen TV) will give you black bars at the top and bottom of your screen. Many people will complain about this, thinking that since there entire screen is not filled that they must be missing what is going on behind those black bars; the reality is that absolutely nothing is going on behind these bars. In fact, you are gaining considerable side information that a full frame version of a given movie does not let you see. Granted, the picture is marginally smaller on non-widescreen TVs, but you are getting the full picture; the way the director (most at least) wanted it to be.
Widescreen is normally referred to as having a 16:9 ratio; most widescreen Televisions you will see will have this ratio. This simply means that for every 16 inches wide the picture, there are 9 inches of height (or simply 1.78:1). Most DVDs though do not perfectly fall into this; common widescreen aspect ratios on DVDs you will probably see will be 1.85:1 (Academy Flat) and 2.35:1 (Scope). The wider the aspect ratio the larger the black bars will be on a normal TV; but in the same turn the wider the picture the more information you would have lost if it were just presented in full frame.
Anamorphic widescreen helps to preserve the DVD format as technology advances throughout the years; namely for those who will be purchasing widescreen and digital TVs. Anamorphic widescreen is similar to widescreen when viewed on a standard 4:3 TV, yet very different when viewed on a 16:9 widescreen TV. The technology itself is created by placing higher resolution video on a DVD, which will end up being essentially filtered by DVD players not attached to a widescreen set. Because your standard TV does not have enough lines of resolution, the video would not be represented correctly; therefore, the player will remove one out of every four lines of resolution from the video until the standard aspect ratio is represented correctly (therefore the black lines you see on the screen of an anamorphic presentation are in fact digitally added). Now when a DVD player playing an anamorphic widescreen presentation is attached to a widescreen TV, the picture is no longer filtered, and essentially (yet not completely), fills up the entire resolution of the screen, while gaining image quality in the process. A non-anamorphic widescreen presentation on a widescreen TV does not do this; instead, it will leave the bars on the sides and the top, unless the user zooms in on the picture. The problem with zooming is that the picture is degraded in the process; this is what makes anamorphic presentations so nice, as image quality is actually gained in the expansion process. To make sure a given DVD is anamorphic, check for things like “Enhanced for Widescreen TVs,” “Anamorphic (of course),” or “Enhanced for 16x9.”
Progressive scan is a technology that helps to make DVDs look better then they already do. To take advantage of this technology you are going to need a progressive scan capable TV and a progressive scan DVD player (although all progressive scan capable DVD players have standard outputs as well that can be used until you upgrade your TV). Progressive scan converts interlaced video which non-progressive capable TVs use, and converts it into progressive video (or 480i to 480p). This allows for much better video quality with highly increased vertical resolution. There are many technologies for doing this conversion, varying wildly in the price versus performance category, which is largely why you will notice some players claiming progressive scan abilities for under $300, whereas others cost upwards of $1000 and greater. On a side note, every PC DVD player is progressive scan capable as all PC monitors are progressive; quality here though is dependant on many other things that most set top boxes do not have to take into account (processor speed, decoder, etc…).
The THX certification does not really fit into this article very well, as it is not a video format; rather it is more of a quality control label, guaranteeing “THX quality” video and sound. This is a certification given by Lucas Films Ltd., which implies that a given DVD video track’s quality reaches their standard for optimal viewing quality. Theoretically, to fully achieve THX quality sound, your entire system will need to bear the THX logo.
What does the future hold for DVD video? Anamorphic widescreen will definitely become the de-facto way to present widescreen video for its ability to greatly enhance the picture on digital and widescreen televisions. In the future high-definition DVD (or HD-DVD) may become a standard; but, do not expect that any time soon. As for technology, who knows where it will go, but it is going to look better and better as we move forward.