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Progressive scan and my t.v's deinterlacer (1 Viewer)

Luke*Ho

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I have a Philips 34pw8520 direct view HDTV. I couple it with a Philips 724AT progressive scan DVD player. While the 480p picture using component cables is stunning, I have found using my DVD player thru my 480i inputs produces a picture that is not a whole lot different than the progressive mode. Why is that? I would expect a significant difference between 480i and 480p. I tried using my other non-progressive DVD player, same thing, not that much of a difference. I assume that when I use my DVD player thru the 480i component inputs that my t.v.'s deinterlacer improves the picture. Can my t.v.'s deinterlacer be that good? The reason I ask is that I only have one set of 480p/1080i inputs and eventually will get a STB for HDTV and will have to move my 480p DVD player to the 480i only input. Any thoughts or insight?
 

Hanson

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If your TV's line doubler does 3:2 pulldown, you're not going to see a whole lot of difference between your player's de-interlacer and your TV's de-interlacer. Maybe some select people can sit down and see the difference if they carefully compare torture tests, but general viewing will not really bring forth any noticeable distinctions. The are certain players with Faroudja/Genesis chips that reportedly make a difference, but it's quite possible that the deinterlacer in your DVD player uses the same chip as your TV.

I myself have a old, first gen Onkyo player, and I couldn't notice the difference between a Panasonic RP-91 and my Pioneer RPTV's de-interlacer. As a result, I returned the Panny.
 

Michael Reuben

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I would expect a significant difference between 480i and 480p.
There is, but you're not seeing 480i. Your TV's circuitry produces a 480p picture, so what you're comparing is the 480p images produced by two different units (the player vs. the TV).

The player has the advantage of working solely in the digital domain, but line-doubling circuitry in TVs has improved so dramatically that the difference is much less than it used to be.

M.
 

Allan Jayne

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Many HDTV's upscale the DVD progressive scan to 1080i as opposed to display it as 960i or 480p. If the TV upscales it, there is an analog/digital conversion performed upon the incoming 480p component video. Incoming 480i has just one A/D conversion to get into the built in de-interlacer and remains in the digital domain when going to the scaler. In the latter case the progressive DVD player loses its advantage of fewer A/D conversions in the overal video signal path.

Video hints:
http://members.aol.com/ajaynejr/video.htm
 

RoyGBiv

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Steven Kempner
I also think it is much less likely that you will see a significant difference on a 34" TV than you will with a larger RPTV.

SMK
 

Bob McElfresh

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The television through the Interlace input is doing a analog->digital conversion, creating new lines, then displaying the video in a progressive fashion.

On busy scenes you can see some artifacts where the internal doubler had a bit of trouble up-converting the video.

There are some test-patterns on Avia that dont move, but should be a better test to A/B compare.

But the differences are in fine-detail, not gross picture quality. This is why you may not notice much difference. Keep in mind that a HD display is all about fine-detail so you WANT to use the best possible type of signal.

I only have one set of 480p/1080i inputs
You are not alone. A good switch box rated for HD signals runs $120-$150. This thread on Inexpensive HD Video Switching should help.
 

Michael TLV

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Greetings

Some DVD players output a 480i signal that is slightly degraded in the resolution department when compared to the 480p signal.

Regardless of how good your TV is for deinterlacing, feeding it a handicapped signal will never bring back the lost resolution.

Regards
 

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