Why I'm Not Going With Blu-ray

Just wanted to toss in this link for folks not up to speed on what is being discussed in 1080p24 30 etc frame rates'
The link to the Wiki page about frame rates in 1080p
http://en.wikipedia.org/wiki/1080p

 

The Upscaling Process

Upscaling is a process that mathematically matches the pixel count of the output of the DVD signal to the physical pixel count on an HDTV, which is typically 1280x720 (720p) or 1920x1080 (1080p). Depending on the upscaling DVD player used determines what upscaling signal output options are available. However, almost all upscaling DVD players now have the ability to output in 720p, 1080i, or 1080p. Then, depending on the TV, that upscaled signal can be displayed as is it comes in, or may require additional processing before the image can be displayed on the screen


This might help explain why many DVD's (but far from all) look pretty close to true hi-def on my system.

 

Define temporal resolution and explain to me how a signal with less information stored in it will have a higher resolution of any kind. What you are saying is making no sense to me from a theoretical stand point.

 

Upscaling is interpolation only and no substitute for real data. Take the latest release on BluRay and upscaled DVD and you will notice a difference provided you are sitting close enough to the display.

 

My vehicles the last three decades have been motorcycles: two BMWs, and two Harley Davidsons. I'd say these are high performance vehicles.

I consider the difference between DVD and Blu-ray to be more than just a little bit. There is a mellowness to the look of Blu-ray that I find far more relaxing than the edginess and sense of 'lines' that DVD, even upscaled to the max, presents. Less fatiguing. I consider it important as I spend a lot of time watching, just as I consider the resolution of my audio system important. I can kill time with a boombox or a tv with a basic dvd player, but. . . the sense of involvement is heightened with my main stereo system and my Blu-rays.

 

How does the car you drive have anything to do with bwy BluRay is better? Illogical

 

Upscaling is a necessity, not a feature. The only difference is what device does what:

1) The player outputs 576i -> TV deinterlaces to 576p and scales to 1080p
2) The player scales to 1080i -> TV deinterlaces to 1080p
3) The player deinterlaces to 576p and scales to 1080p -> TV shows 1080p

Method 1 or 3 is generally best. Entirely depends on what TV and player you have. Method 2 is inferior because deinterlacing should be done before scaling for maximum quality.

 

True, but most of my favorite DVD's (Beatles related) are not available in blu-ray or because they are older footage don't show a dramatic improvement on my system.

 

These car analogies would make more sense if all cars cost about the same amount of money. They don't - you can get a decent Civic for $16,000 but you pay much more for a "high performance" car.

On the other hand, a Blu-ray player isn't a lot more expensive than a DVD player. If DVD players were $50 and BD players were $500, the analogy would fit, but that's not the case.

As I've said, I don't care if anyone here has BD or not. If you're happy with DVD, that's cool. The comments that grate are those that feel they must disparage BD and say it's not better than DVD...

 

Temporal resolution is how smooth it is. A 50/60 fps video looks a lot smoother and more life-like than a 25/30 fps video.

In terms of what we're talking about, 1080i doesn't have less information than 1080p, it just has different information. Let's take an example:

1080p/25: 1920x1080 frames, 25 frames per second. Each frame is complete and 1/25 seconds apart, so pixels per second = 1920x1080x25 = 51840000.

1080i/25: 1920x1080 frames, 50 fields per second, 25 frames per second. Each 1920x1080 frame is made up of two 1920x540 fields. Each field is half of a frame and separated by 1/50 seconds. So, pixels per second = 1920x540x50 = 51840000. This will be deinterlaced to 1080p50 (see below) but obviously since this is interpolation, it won't look as good as pure 1080p/50

1080p/50: 1920x1080 frames, 50 frames per second. Each frame is complete and 1/50 seconds apart, so pixels per second = 1920x1080x50 = 103680000.

The first two are what exists today. Both have the same information, it's just that one has higher spatial resolution and one has higher temporal resolution. The former is used for films (albeit at 24 fps instead of 25), dramas and anything else where you want that "film" (i.e. not-smooth) effect. The latter is used for most things, where it should look as life-life as possible (news, comedies, talk shows, whatever) and/or requires smooth video due to fast-moving stuff on the screen (sports).

1080p/50 and 1080p/60 aren't used today but are much better.

 

I agree.

 

Divide that by two for the deinterlacing and one only gets half the bits displayed on the screen. I still don't see a definition for temporal resolution.

 

I don't think you understand what deinterlacing is. Where does this "divide by two" come from? You don't chuck away any information when deinterlacing, you add more information by interpolating the fields to full frames! In other words, you don't go from 1080i/25 to 1080p/25, you go from 1080i/25 to 1080p/50, which has twice the temporal resolution as 1080p/25.

I also can't see how you don't get what temporal resolution is. 1080p/50 has twice the temporal resolution of 1080p/25, since the frame rate is doubled. You see? Spatial resolution is sampling in space - the image is essentially infinite pixels but you're sampling it at 1920x1080. Temporal resolution is sampling in time - the motion happens over, say, a second and you're sampling it 25 or 50 times over that second. If you sample 10 times per second, it wouldn't look very smooth at all. If you sample 1000 times per second it'd look ridiculously smooth (but no playback system supports such frame rates).

 

Well according to this article, we're both wrong.

http://www.hometheater.com/content/1080i-v-1080p-0

 

I do understand what deinterlacing is. My mistake was in that CRT tubes displayed the even numbered rows followed by the odd numbered rows, hence teh divid by two. LCD, and Plasma's don't deinterlace like CRTs. Me bad.

 

Sure they do. Plasmas and LCDs have to take the even numbered lines (from interlaced sources like TV), and the odd numbered lines (aka Fields), then combine them into Frames, i.e. progressive scan.

 

Yes but CRTs before progressive scan only displayed 480i or only 240 frames per second. That's what I was referring too.

 

Yes, CRTs just display interlaced content as it is - interlaced. LCDs and plasmas are natively progressive so must deinterlace first.

That article is talking about films being sent to the TV via 1080p or 1080i, which I would agree makes no discernible difference. There's two ways of doing it:

- 1080p/24 over 1080i/30 using pulldown. This should be reversed by the TV and is thus lossless.
- 1080p/25 over 1080i/25 by essentially "wrapping" the 1080p content in a 1080i stream. This happens with all films on PAL DVDs. Any deinterlacer worth its salt will notice that there is no temporal difference between the fake "fields" and will deinterlace it back to the original 1080p/25 with little-to-no loss.

Natively 1080i/25 or 1080i/30 content is different though. The article also rather old - it says that TVs have to convert 1080p/24 to 1080p/60 before display anyway, which hasn't been the case for years. Most TVs now display 1080p/24 at 48 Hz, 72 Hz or some other exact multiple, which is essentially the same as displaying it at 24 Hz.

 

Im getting the sense you may not totally understand "Upscaling" if you truly believe that.

Upscaling happens on ALL HD tv sets, not just in the DVD player. Its function is ONLY to get the best possible resolution "match" from a SD source and convert it to be able to be displayed on a HD screen with a larger resolution.

It doesnt actually "increase" or add to the resolution or even make it appear to be HD at all, but its simply like making a small picture fit a larger screen with the least amount of degradation, when converting from one size to another. Sure some upscalers look better, But ALL HD tvs themselves are able to upconvert a low resolution image as a built in feature.


The best it can do, in the end, is "Get the best" from the low resolution SD source with the least amount of degradation.

It DOES NOT increase resolution in any way, and in fact simply interpolates elements to give low resolution DVD a less scraggly appearance. There is no jump in resolution, not does it "Create" an HD picture" from SD.

 

Actually you are back peddling elizabeth.


WE all KNOW blu ray is quite a bit better. Not a "little bit". Why not just say you know its a lot better, but dont care. I can easily understand that, but to disparage it and make comments like that is what is keeping your lack of understanding going, or making you out to be a "Semi-Troll"

 

All HDTVs do have their own internal scalers. This fact often gives way to comments that upscaling DVD players aren't needed, because a HDTV will upscale all incoming signals to its native display resolution anyway.

In response, you have to keep in mind that the scalers built into most HDTVs are usually very basic and often times do not have advanced processing to eliminate scaling artifacts, such as jagged edges, motion adaptive noise reduction, mosquito noise, and detection of various video and film cadences. All things considered, chances are that an upscaling DVD player will have better video upscaling capability than a typical HDTV. Such as my Denon 3910.

 

Traditional (non progressive scan) CRTs can't display framer-per-second. They display 60 fields per second, aka 60i.

 

The DTS MA on it is just as big a leap from the DVD version which I shall never play again.

 

At 240 lines alyernating between odd and even lines. Are we on the same page now?

 

I guess? There's a big difference between 240fps and 60 interlaced fields per second. Just trying to help, for those reading on, who are at the cusp of grasping some of these terms.