Electronic Life - The Best BluRay Player Is Still… The PS3!
July 2, 2008
Hi, there! Back from reviewing a lot of data about the end of the high-definition DVD wars. Sony, with its BluRay hi-def DVD format won the marketing war for hi-def optical video players. This is the device that will supercede DVD players for playing high definition video. First, a review of standard-def TV and High-Def TV
Standard Definition TVs
Standard TVs (those big, bulky boxes about as deep as they are tall) use Cathode Ray Tubes (CRTs) to display a picture. A moving electron beam scans across the screen from left to right, reaches the far end and temporarily turns off, then resumes scanning again from left to right a little lower on the screen.
You can actually see the series of horizontal scan lines if you stand close enough to the screen of a large TV, particularly if it is an older one. There are 480 visible scan lines.
One more detail - standard-def TV has a width to height ratio of 4 to 3 (abbreviated as 4:3). The screen is a little wider than it is tall.
DVDs are actually digital signals recorded on a reflective background, a series of dots or no-dots. And the DVD signal holds values for 640 locations (that ratio of 4:3) along each scan line. Thus a standard-def TV has a resolution of 640 by 480.
Why is this important?
Have you ever noticed that if you watch a movie on TV and then watch the same movie from a VCR that the VCR image looks “softer” and less sharply defined. Look particularly at any text on the screen. The reason is that VCRs are not capable of reproducing all of those 640 by 480 locations.
TV resolution is commonly measured by “vertical lines of resolution.” These are the number of separate horizontal scan lines the device can reproduce. We know that standard-def TVs can reproduce up to 480 lines of resolution. VHS VCRs can only reproduce about half that - about 240 lines of resolution.
This means that the smallest detail the VCR can play back is about four times as large as the smallest detail a standard-def TV can display (the ratio of 240 to 480 applies in both the vertical and horizontal).
The Math of Standard-Def TVs
Standard-def TVs display only half of the picture every sixtieth of a second. This is due to the original design circuitry back in the 1940s when TVs were invented. They couldn’t cost-effectively make and keep running circuitry that could display an entire 640 x 480 TV picture (a “frame”) in one sixtieth of a second.
They solved this by cutting each “frame” in half, into two “scans” so that every odd scan line was done during the first one-sixtieth of a second (one scan) and then every even scan line during the next one-sixtieth of a second. This is called “interlaced” scan. In electronics parlance, this is also the “I” in the “1080I”, above.
NOTE: In Europe and some other parts of the world where electrical wall power runs at 50 cycles per second, they usually run their TVs at a rate of 25 “frames” per second (fps), with each scan occurring every one-fiftieth of a second.
This results in more scan lines but the amount of data overall is the same as the standards were developed at the same time with the same electronic circuits and parts. It takes just as long to scan across the screen on a 50 cycles per second TV as on a 60 cycles per second TV.
Regardless, a standard-def TV frame has only about 300,000 “dots” in it and displays that every thirtieth of a second.
Compare what you see on the movie screen to standard-def TV and…
The Math of High Definition TVs - 720P
In the USA, high-definition TV is defined as either “720P”, “1080I” or “1080P”. You’ll see that referred to in the ads and in stores. Let’s see what that means.
The 720 and 1080 you can probably guess means the number of horizontal scan lines - and you are right!
But there is an additional factor in the equation - HDTV screens are defined as having a 16:9 width to height ratio. So each scan line has a lot more info in it. The 720P scan lines have 1280 data locations along each line and the 1080I and 1080P scan lines have 1920 data locations along them.
A little quick math shows that an entire 720P screen has almost 1 million “dots” (720 x 1280) on it. This is about three times the size of a frame of standard-def TV.
But we haven’t gone into the “P” part of the “720P.”
Electronic circuits are far more advanced now and the entire “frame” can now be displayed (”painted”) in one-sixtieth of a second. Thus “frames” and “scans” are now the same. The entire frame is “painted” by starting at the upper left corner, going all of the way across, going to the very next scan line and so on, skipping all of the “odd” and “even” scan line stuff. This is called “Progressive” scan and is the “P” in the “720P” and “1080P”, above.
This means that 720P data is displaying an entire frame in one-sixtieth of a second. That is twice as fast as the standard-def TV screens, so HDTV 720P is actually displaying those 1,000,000 dots twice as often as standard-def TV displays its 300,000 dots. 720P TV actually uses six times as much data.
One of the easy ways to see the higher resolution of 720P signals is to look at the hair of the “talking heads” - you can see every strand! And any text you see will be much sharper!
The Math of High Definition TVs - 1080I
Then there is 1080I. This means that there are 1080 scan lines and each line, using that 16:9 ratio, is 1920 dots long. A little more math says this is about 2,000,000 dots, or twice as many as in 720P. But it is 1080I (interlaced!), so it only occurs half as often. The result is the same amount of data is in a 1080I signal as in 720P signals.
1080I signals give you even more on-screen resolution. The problem is that you have to be relatively close to the screen to see the difference between 720P and 1080I - about 1.5 to 2 times the diagonal measurement of the HDTV. That’s about 6 feet from the HDTV to your eye for a 42″ screen (I’ll bet you don’t sit that close!). And some motion will not look as good on 1080I as it does on 720P.
And Now The Math of 1080P
1080P obviously uses twice the data rate of 1080I, so it uses twice the data. Current broadcast standards are such that no one will likely transmit in 1080P because it requires too much data to be sent over the air. The same problem with seeing the difference between 720P and 1080P occurs as with 720P vs. 1080I although motion would be as smooth in 1080P.
But What About Prerecorded Shows?
Pre-recorded shows on optical media have no major technical problem in being displayed in 1080P, other than the very “minor” one that, up until recently, no current media could hold enough data to contain an entire movie. Thus started the marketing war over the “next generation in optical media.”
From above, we know that 1080P will require about 12 times the space as standard-def TV, so that means we need about 100GBs of storage instead of the current 8GBs maximum on DVDs. Then the scientists chimed in with a better way to compress the video data so only about one-quarter to one-third of that was needed (DVDs already compress the data a lot - hi-def video compresses it even more). Technically, a system to store and play back 30GBs of data over three hours is much easier to develop than a way to do the same with 100GB.
Two “armed” camps developed arguing over the best technical method to do this. One argued that a system that used the same equipment now used to press DVDs would be cheaper in the long run. This was the HD DVD standard pushed by Toshiba and others.
The other group, led by Sony, said that their method could store more data and that it was therefore better. And a marketing war ensued. Eventually the BluRay camp won.
Now That You Are All Asleep
I’m not going to go into the technical aspects between players here but there is some controversy about what is the best BluRay player out there. Some say Pioneer makes the best players, others say Panasonic and there are the Sony fans. But all of the good players are well over $600 USD, have slow load times and some don’t even have the latest version of the BluRay standard, version 2.0. This does not even include having the latest audio capabilities.
And The Winner Is…
There is one inexpensive player that does essentially everything you can ask a BluRay player to do, is easily updatable, has fast load times and is inexpensive - the Sony PS3 with its cheapest model for $400.
With its May 2008 update, the PS3 will be able to play both of the highest fidelity audio streams available on BluRay disks. Sony originally included support for full 7.1-channel support for Dolby’s lossless TrueHD codec, in addition to Dolby Digital and DTS. With the May ‘08 update, support for DTS’ lossless audio coding, DTS-HD Master Audio is added.
Using the PS3 as a signal source for your Hi-Def AV system is not a perfect solution unless you can handle HDMI 1.3 (High Definition Multimedia Interface) output to your amp, preamp or AV receiver. There is no separate breakout of the analog 7.1 audio signal. Also, of concern to some, the PS3 cannot upconvert DVDs or 720P signals. Your HDTV has to do that. And you have to buy a separate $30 remote to easily use it as a BluRay player.
Still, you can buy the PS3 for as little as $399.99 at Best Buy for the 40GB model that can do HDMI 1.3 output. And it can play CDs and SACDs which the BluRay players cannot. And you can play games!!!!!
You can read other reviews about using the PS3 as a BluRay player at UltimateAV, engadgetHD, PCWorld, and by Googling “PS3 as BluRay player”.
Email this article to a friend - or a nemesis, it doesn't bother us.
Subscribe now to receive notification of new Free Articulator articles like this one.
[...] His short pieces on technology are humorous, informative and fun. One of his recent articles on the PS3 and BluRay was frankly [...]