HD1080i De-mystify HDTV 1080i ::: know why before you buy

Friday, December 08, 2006

1080 - Upscaling to HD from lower resolutions

I get 2 specific format related questions. I get way too many search result hits from this.

1) How does a 1366 x 768 resolution Monitor display 1080i?
2) How does regular DVD (480) display on 1080?

HD1080i on a 1366 x 768 display
Short answer is that 1080 sources are scaled down and therefore are no longer 1080. There are people that say the alternate 720p HD is perfect for 1366 x 768 displays, but quite frankly, 1366 x 768 is enough different from 1280 x 720 ( 720p resolution ) that regardless of what your inputs are getting, you will be at the mercy of the HD display scaling firmware. Rescaling and de-interlacing any source video is non trivial and can produce really poor results.

Pixel for Pixel ...Numbers:
1366 x 768 display resolution is neither 1080 or 720, and doesnt exist in broadcast specifications. It is just a convenient size for manufacturers and thats why it exists.

The methods of scaling downward from 1080i ( 1920 x 1080 ) to 1366 x 768 typical resolution should a nice enough image, since more pixels are available than are needed. Newer displays generally do better than older designs, but in most cases de-interlacing is the first step in the down scaling process, and you need to see it live and in the store to determine if you like how any given HDTV performs. That is my advice because i have seen such a huge disparity in scaling quality that no general answer will be correct, except perhaps to say that in 50" or larger HD displays, 1366 x 768 plasma will look less crisp side by side with lets say a 50" 1080p SXRD.

UPSCALING: 1080 and the 480i standard DVD
Your basic DVD is 1/6th the resolution of a 1080 display.
You can do something about it. Process the DVD image quality and prepare it for your 1080 Screen, hook it up with component, or HDMI connector and FILL THAT SCREEN, with progressive processed, clean 1080.

Upsampling Scalers.
This task is of scaling larger images from smaller sources is complex, and in best case situations it produces the ideal scenario for the 1080p display owner, since a nicely upsampled DVD in an HD1080 monitor can fill the screen properly as opposed to a pillarbox 4:3 or letterbox 16:9 "zoom" scaled image which is just low-resolution blocky stuff made bigger. You need some technology, and an easy way to recognize that it is there.

Enabling Technology ::: Short answer;
DCDi by Faroudja. If the device/player has this firmware feature, then you will love it, award winning de-interlacing and Directional Correlation edge detection and managament at the per-pixel level , or in other words, proven high tech that looks great, but you need a new DVD player to get this happenning for you. A sample of what i suggest...

OPPO DV981HD Product Webpage for $230 or less.
DCDi Progressive Scan DVD player with HDMI into a nice 1080p image.

Yamaha DVD s2500 Product Webpage for $750 or less
DCDi Progressive Scan DVD player with HDMI, well liked by the pros.

DCDi Faroudja Processing performs the magic of de-interlacing a source and then processing that, frame by frame, in real-time, for scaling. It has been the choice of film makers and high-end projection systems for years. It takes almost anything in - and creates 1080p.

I'm not going into detail further but The Pioneer Elite -(No DCDi) , - works well, this unit is superb at a substantial price, and The Denon highest-end progressive DVD player unit, always a favorite, is pricey and many times preferred over anything else.

Lets discuss just a bit, since a lot of things have to happen for a lower resolution to be converted to a higher resolution. For one thing, the source low-resolution must be detected and made into a complete image first, this is called progressive display. ALL DVD stuff is interlaced Mpeg2 so basically it must be sampled and stored into memory in the player for processing, making it available for pixel level analysis, in short, the process requires computing memory and horsepower.

Problems arise when images are upscaled and converted, jaggy edges, especially fast moving angular edges, will look bad. DCDi by Faroudja handles that with Directional Correlation math-whiz processing that detects and fixes the upsampled and scaled image edge to remain smooth, eliminating the shaky dot crawl zig-zag of simple bicubic digital image processing. Actually it does a lot more than that, but what you need to know is that the best stuff has DCDi by Faroudja to handle scaling.

So for the Case of regular DVD play into 1080 display, it is proper to get a thouroughly enjoyable experience and well worth your existing DVD libary investment to have an OPPO player or DCDi by Faroudja enabled playback unit. Harry Potter and Lord of the Rings DVDs in widescreen DVD will be truely a see again and love it's look kind of experience.

Yes , if you have a nice 1080p LCD screen, it may do all your scaling for you.
In such a case i have found that Component Input scaling behavior with a DCDi equipped monitor behaves just slightly better. Usually you can scale the display with a couple methods.

One would be at the cable/dish subscriber box in thier ZOOM mode, which is not usually very good, another is at the monitor if it has a ZOOM scaling option.

Genesis Display Perfection® technology
This is the best implementation of DCDi

Westinghouse Digital and LG use this in thier 1080p display product lines.
I have seen and tested both and they are for me at this moment, the best solution for input resolution display scaling. Although this information is not well known or even featured in marketing these products, the Genesis DCDi DIsplay Perfection chipset rules what you will see.

Is superb, they have a tuned solution that is specific to the unique display management of color and process, so a tech discussion here is not something i can do, suffice to say it can be trusted. If your have a Bravia or Grand Wega XBR than you are going to want to let the display do your upscaling for you. My personal best-of bang for the buck is still the SXRD XBR stuff. Sony has a sence for price-point performance that beats almost everyone but Westinghouse digital.

Life is Good... these people have superb R&D.
Face it... LG / Phillips combination of euro-brilliance and korean manufacturing, have so got this situation under control that my other posts cover it in more detail. ANY top of the line LG 1080p display made recently is going to do a fantastic scaling job, just plug the DVD players-video in and let your LG do it all. I insist that you go see LG stuff for yourself. Currently my chipset of choice is in the LG 1080p lines. http://www.lge.com/

very good is all i can say, it deserves more attention from me but i will get there.

Does very good svideo upscaling, but i have no indepth knowlege on how they are doing it, and that is only in the 1080p stuff i have seen... they seem still to be interested in plasma which at 1080p is rather pricey

excellent - but i dont know how they do it yet. The Pioneer Elite has fooled several people into thinking they are seeing an HD source when looking at widescreen Lord of the Rings regular ols DVD. Yes its that nice, but you probably have enough wallet for this to also afford anything else you want.


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