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Oh here I go laying my head on the block..


I've researched this for a while and I feel I'm missing something. Can someone confirm or clear up somethings for me?


1). Line Doubler, Tripler, Quader --- Holds signal for a short time and sends more lines at once, making an interlaced signal into progressive.


True / False / explain


2). Scaler --- Takes the native format of the signal and converts it into a different picture size. Such as regular DVD into 720p.


True / False / Explain


3). HTPC --- Does both of the above based on configuration. No need for above hardware.


True / False / Explain




Now with that said is there anything that takes say 4:3 and changes it into 16:9? Also what is the device that deals with keeping the pulldown correct? Is the a Curt Palme type guide for this?


I ask becuase I'm thinking of just getting V880n and I wonder if I will need any of the above if I do so.
 

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1) - Not qualified to answer


2) - Yes. Can also change the framerate, aspect ratio, etc. Most of the newer scalers will let you configure custom resolutions - I'm running 660P - so you can optimize the PQ on your display device.


Also, most will accept multiple video sources - Component, S-Video, RGBHV, DVI, and act as your switcher - though some restrictions apply due to HDCP compliance.


3) - Yes, but many find them to be tedious and requiring as much set up and twiddling as a CRT PJ.


I recently got a scaler and have been pleased with the improvement it can make in my PQ.


There is a good forum here on AVS "Video Processors". There are many helpful people there and a lot of good information - sometime WAY TOO MUCH information - I mean like "What is the difference between video source de-interlacing and film-based deinterlacing and do I care???" LOL


Hope this helps some,


Good luck and have fun learning!!!
 

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As I have said before.....an HTPC is not complicated. It doesn't have to be anything more than a regular PC with a decent video card....and you plug your projector in just like a monitor....it is actually quite SIMPLE.


It doesn't REQUIRE tweaking.....but allows you to do all sorts of tweaks that aren't available with stand-alone doublers/scalers/etc. Without my HTPC....the PQ would be worse.


And you can play all of your dvds right on the computer without needing a DVD player.


If you have a PC that you can try it with....I would encourage you to do so.
 

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OK! Let me take a swing at it.


First let's talk about interlaced and progressive scan. This feeds into other things.

Here's a visual. These are lines:


1

2

3

4

5

6

7

8


With an interlaced images, lines 1,3,5,7 are displayed top to bottom. Then lines 2,4,6,8 are displayed top to bottom. So not all lines are displayed in one pass.


With progressive, lines 1,2,3,4,5,6,7,8 are displayed top to bottom. All lines are displayed in one pass.


Progressive is also called line doubling. Its kind of like splitting a deck of cards and shuffling them back together.


Line tripling or quaduling (sp?) is different. There's no additional lines to shuffle together. The information, pixels if you will, is looked at and an algorithm determines what pixel WOULD have been there IF there were more lines. It's doing interpolation. So it's making up extra pixels based on what's around this blank spot. This is also called upscaling in the DVD player world.


Since line doubling is really a different process than line tripling or quaduling, it causes confusing. I think I've got it straight now.


Other things you can do with the picture is change the frequency. From 60 kHz to 48kHz to 50 kHz.


You can also convert from NTSC to PAL format.


You can also convert the aspect ratio - 4:3 stretched to 16:9, 2:35:1 compressed to 4:3. It's usually pretty ugly.


You can also letter box a 16:9 or 2.35:1 rectangluar image to fit onto a 4:3 square screen or the opposite (pillar box). You'll have black horizatal bars with letter boxing and black vertical columns with pillar boxing. But the image will fit on your screen.


You can ajust the gamma or brightness or contrast or video noise reduction or ...


You can transcode (convert) component (3 cables) to RGB (5 cables or VGA).


You can switch between various sources - VCR, DVD, Cable, etc.


Plus more


A scaler can do several of this tasks. Which ones depends on the scaler.


A line doubler will usually convert interlaced to progressive. It may do more tasks. As a product type or definition or label, I'd say this as fallen out of favorite. Replaced by the term scaler. Yes older line doublers still exist.


A line tripler or quaduler will do the interpolation and maybe more tasks. Most likely interlaced to progressive and then the interpolation. As a product type or definition or label, I'd say this as fallen out of favorite. Replaced by the term scaler. Yes older line triplers/quadulers still exist.


I don't have experience with HTPC but bet they can do it all.


A Momitsu V880N can do some of these - progressive scan, upscale 480 to 720 or 580 or custom resolution, change the frequency, letter box, pillar box, etc. It can NOT control gamma. The Momitsu is an decent, inexpensive option that give you lots of options and power. There are more expensive options (better DVD player and scaler or DVD player and MP-5 transcoder or HTPC) that can give you a better PQ.
 

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Quote:
Originally Posted by GEBrown
I recently got a scaler and have been pleased with the improvement it can make in my PQ.
Gary, I though you sold your Lumagen? What are you using now?
 

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Quote:
Originally Posted by PAW
Gary, I though you sold your Lumagen? What are you using now?
Umm . . well at the same time I got a really good deal on a DVDO iScan HD (not plus).


I tried them both. Kept the iScan, even though I shouldn't have - should use the money to pay other bills, but, well, you know "He who dies with the most toys . . "


:D
 

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Susan - while an HTPC isn't complicated, per se, there are complications. One needs to find a decent software dvd player, one that works with both the sound card and the video card. One may have to upgrade to a different sound card, in order to get dts over spdif. OR find the software player that indeed does output dts and DD over the soundcards SPDIF out. and if you are using a CRT, chances are excellent that you will have to reconverge a new memory block for each of those cool resolutions that you output using the HTPC.


I don't consider all of the above tweaking - but it is a lot effort, just to get a picture, at which point one can BEGIN to tweak (powerstrip, TT, ffdshow, ....) When I got my first Barco, I was just dumb lucky that the first doubler I bought was an Iscan Pro - I connected everything up, and it all worked. :) Which was good - I sure didn't know enough to do anything about it, if it hadn't worked, and I had not found this forum, so had no source whatsoever for answers to questions.


Don - nothing "changes 4:3 into 16:9, but many units will STRETCH 4:3 into widescreen format - even my ancient DVDO Iscan Pro has a "normal" and "squeezed" switch. And naturally, with all the custom formats on a modern scaler, that can be done. Or you can use a memory block on your pj to do the same thing. What I would like is a scaler like on some of the newer digital pjs, that does a variable stretch, leaving the center mostly untouched, and just stretching the edges to fill out my 16:9 screen.
 

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Quadrupler. The term is Quadrupler. Although a decent scaler should be more flexible than just giving multiples like doubling, tripling, quadrupling.
 
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