Video Processing - What Can I expect?

[rozel]

Over the past few weeks I have taken delivery of my new LCD TV, a Sky HD box to replace my trusty Sky+ box and a PS3 to play BD discs while I await the arrival of a Samsung BD-UP5000. This is my first move into the new world of Digital and a whole new world it is! Having seen a few BD films already and having streamed some 1920 x 1080 videos from my PC, I have to say the quality is breathtaking! Yesterday I stripped out all my old Scart Leads/switchers/and my faithful RGB to Component converter and replaced them with a ShinyBow Component Switch and Component leads in order to have things like they were before albeit in new High/Higher Definition.

I simply would like to know what I can expect from my various sources - maybe some kind person can tell me please? My equipment below is transmitting pictures as follows: -

1. TV - full 1080P capability
2. Projector capable of projecting 720P pictures

Questions : -

a. My Projector has 2 Component channels - namely YCrCb 15kHz and YCrCb 32 kHz. What do these outputs mean? Am I to think that the 15kHz channel can project images up to 576P with the 32kHz channel for 720P images? I "think" this is what is happening at present lol!

b. My Phillips DVDR and Azur 540D are both capable of "Progressive Scan" - so playing a standard DVD, what maximum quality of image can I expect through both my displays - 576P?

c. Playing BD discs through my PS3 I'm getting 1080P through my TV - am I correct that I will receive "downscaled" 720P images through my PJ?

d. "Upscaling" - is this another term for Progressive Scan? My PS3 can Upscale - I'm not sure whether my other 2 DVD players can - what does Upscaling really mean and what quality of picture can I expect to receive if Upscaling is invoked - say when playing standard DVD's?

e. Sky HD - playing through my TV, I get 1080i picture quality. When routing through my PJ - what can I expect to get? 720P? and will it matter whether transmissions are either SD or HD?

From all the above, you can see that I'm confused - have buried myself in all my manuals this week end and cannot understand the way each manufacturer reports it's Device's capabilities Video-wise.

Hope someone can help

Regards

roz

ps "Late Edit" With reference to the above, what would the benefit be if any to having either a Lumens or Themescene Scaler within my setup?

[rozel]

Nobody? - Please someone help a noob

roz

[Liam @ Prog AV]

I think you've confused yourself heavily by trying to tell yourself if you are getting "720p" quality or what have you. You need to seperate out what the signal is on disc/broadcast, and what the resolution is.

So with Sky HD, HD channels are 1080i resolution. The TV will show this with no downscaling of information, the projector will show this but will downscale some of the line resolution (so it won't be quite as sharp).

DVD is 576i on disc, with 576p being the deinterlaced or progressive scan output. In both cases your displays will be taking this information, and running an upscaling process to make it fit the amount of pixels that display has. So the TV will be using 1920x1080 pixels to show a 576p image, and the projector if it's a D20 will be using 1024x576 pixels. In both cases the varying performance of the rescaling circuits in each display will dictate how lossy the process will be.

The two inputs on the projector are I think one for interlaced only (576i not p) and the other for progressive scan and HD (576p, 720p, 1080i probably).

Upscaling is simply taking an image of one resolution, and stretching it over more pixels to fit a display which has a different resolution. Downscaling being the opposite, taking say 1080p and downscaling it to fit a display which only has 1024x576 resolution. You have to remember that upscaling itself adds absolutely no quality to an image. In fact it is a lossy process even at the very best of times. The reason it has become a popular subject area is because some TVs do it really badly, so having a DVD player which does it better would see some improvement (of course the marketing people love to make it sound better than it is and try to confuse you into thinking you are getting HDTV quality out of it).

[rozel]

Liam many thanks indeed for that. As I suspected the whole matter is more complicated than I had first envisaged and despite reading what you have told me, I'm still trying to digest it and to understand it better.

Yes my PJ is a Domino D20 - my supplier has confirmed that it is capable of projecting images at 720P and that the circuitry is excellent in upscaling, in this respect. Previously I was only projecting RGB signals and have not yet climatised to these Component channels.

I am confused that whilst I can easily find out what resolution my TV is displaying the images input to it are, my PJ doesn't easily provide this information.

This whole query came about by the fact that when I was playing back a BD DVD through the PJ, it projected it through it's YCrCb 32 kHz channel as it does when projecting images via the Sky HD box but the other evening I noticed that a standard DVD playing via my Azur 540D came through the PJ's YCrCb 15kHz channel. I simply thought how strange as I thought my DVD Player Upscaled and thought it would display through the YCrCb 32 kHz channel as with BD discs and the output from the Sky HD box, but it did not.

It was then that I wanted to know more. I am still confused as to the difference between Progressive Scanning and Upscaling.

And I want to know, given my existing setup, whether I would benefit form some form of Scaling device as mentioned extensively in this Forum.

Any further information/advice would be gratefully received.

roz

[Liam @ Prog AV]

To be honest with you, does it really matter what line frequency is being reported?? So long as the end result is the best image.

The Domino 20 is a 1024x576 projector. It can receive 720p, but it will downscale to it's own resolution.

Deinterlacing (converting to progressive scan) is taking an interlaced signal (e.g. 576i) and turning it into a progressive signal (e.g. 576p). Note the denotion at the end of the number. Scaling is changing the amount of pixels the signal is made up of e.g. UPscaling 576p to 720p, or DOWNscaling 1080p to 576p.

Best bet is for you to search around these forums to find in depth information on what these things mean.