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I was reading reviews on a JVC XVS65GD progressive scan player and noticed a lot a people saying it has "true" progressive scan? What do they mean by this? Are some progressive scan players just line doublers? And is there anything wrong with this player? I have seen sell for 120 bucks. Must not be that good of a player.
 

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I believe it might be in reference to whether the DVD player's de-interlacer performs the inverse 2/3 pulldown function. As I've understand it, various DVD players vary in their performance, as it supposed to properly recognize both film based and video based material as found on the disc. Some player's de-interlacer can introduce picture or motion artifacts if it doesn't deal with the information properly. Actually no extra information is added on the disc, the DVD contains the orginal 24 frames per second that was originaly captured. Algorithms or what the industry calls "flags" are stored along with the picture information to not also save space but help the player return the picture to it's orginial form.

For interlaced DVD players, they essentially look for the flags to help them retrive and display the picture to a non-digital(or High Def) television monitor. For true progressive scan DVD players they must not also feed the 31.5khz(double the speed of analog TV's) signal to the monitor but SHOULD know exactly when to ignore the "flags" hence the name inverse 2/3. But this has been known to confuse the player around chapter breaks, and when the scenes in the movie change from being captured with a film camera to a video model.
 

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"True" progressive means the manufacturer has a bold marketing department! It's a progressive signal or it's interlaced; there aren't shades of grey, and an oscilloscope will answer the question quickly. I'd love to see an example of a "false" progressive player.


That said, the way(s) the player makes progressive frames out of the (always) interlaced DVD source is a matter of some craft, and good players do a nicer job than bad players. If you're curious, there's a very nice (if often linked) treatment of the topic here:

http://www.hometheaterhifi.com/volum...e-10-2000.html
 

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Having said that, whether it properly performs 3/2 pulldown (via analysis, flags, etc.) is very important--as was pointed out.
 
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