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raygun on 27 July 2010
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Ssenkahdavic said:
raygun said:
Ssenkahdavic said:
raygun said:

Actually....1080i doesn't equal 720p, pixel wise. Maybe close if your just looking at one interlaced frame, but with 2 frames, 1080i is 1920x1080 pixels. Each interlace frame is 1920x540, but they are different interlaced slices of the total 1920x1080 frame. 720p is just 1280x720 pixels.

But, I don't think we can say that the "1920x1080p @ 59.94/60Hz (Top-and-Bottom) mode is interlaced, wouldn't they call it such? They are averaging every 2 vertical lines in a1920x1080 frame (subsampling) to end up with frames that are 1920x540. How can they call this a 1080p mode, I wonder? May be it's cross eye interlacing, the left eye gets the even lines, the right eye the odd lines? Seems I remember this being done in the past. 

Anyway, I would be totally content with a 1080p game running at 30hz, or better yet at 1080i at 60hz. 30 hz is what most console games run at anyway, and have trouble even getting that. Sure there's a few 60hz exceptions, StardustHD, WipeoutHD. But WipeoutHD, the sneaky bastards, uses 'variable horizontal resoulution', 1280 to 1920, and it still tears every now and then. 

Getting back to the OP, I personally am ready for a new TV, I like 3d, and will be buying one. It's either a panasonic vt20 or the new Vizio 480hz lcd's, depending on the reviews. A 60" laser or dlp is just too big for my apt., and I just saw the 3d adapter for samsung 3d dlp's listed at $300, without glasses. And i'm one of those people that notice the dlp rainbows.

You are confusing Hertz (Cycles per second) with FPS (frames per second)  While sometimes they are interchangable, for the most part they are not.  One is how many times your screen "redraws itself" per second (hz) and the other is how many different Frames are drawn Per second.  When they are equal (or FPS > Hz) a much smoother picture is born.

 

And for top/bottom (from page 7 on the 3D HDMI white sheet)

"For Top-and-Bottom, the original full left and right pictures are sub-sampled to half

resolution on the vertical axis. Sub-sampled pictures are arranged in Top-and-Bottom

layout. See Figure 8-6."

Ssenkahdavic, I mentioned the subsampling above," They are averaging every 2 vertical lines in a1920x1080 frame (subsampling) to end up with frames that are 1920x540" My point is how can they call this a 1080p format, when it's actually only 540p???? Do they just double the verticle lines at the tv to make it 1080p, or are they some how interlacing to get back up to 1080p? Just doubling the 540 to get back to 1080, then calling it 1080, is...lame.

I wasn't confusing the two, they are the same spec. applied to different things. 60hz refresh means 60 frames drawn per second. If a monitors refresh rate is 60hz, it's entire screen is redrawn 60 times a second. If a game runs at 320fps, and you have it hooked up to a 60hz monitor, your still only going to see 60 fps. I meant that if the maximum a tv could show was 1080p at 30hz, which is 30 1080 frames per second. That would be more than enough for 95 % of the games on consoles, that struggle to do even 720 at 30fps. 

Just read up on the 480hz refresh backlight trickery of those new Vizios coming next month, i'll just have to wait until the reviews come in.

Interlacing means every other line (odd then even) per pass (ie 2 cycles for 1 full frame).  This method is not interlacing anything.  The top is all the scan lines 1-540, just as the bottom is 1-540.  They call it top/bottom (one is on top of the other) and together they equal 1920x1080p (it does not say anywhere it is per eye, that is limited to framepacking)  This is still progressive since they are not interlacing anything in the signal.

Go and look at the framepacking example.  That is the only true way to get full 1080p PER eye.

Have you ever run a game at 320fps on a 60hz monitor (without a limiter) ?  They are in no way the same.  Your monitor will only redraw 60 times per second, but your machine is outputting 320frames in that same second.  This means that you are getting 4 frames per cycle (or only 1 in every 4 frames is being displayed).  What does this look like? Fast forwarding a movie.

fps is from source (computer, ps3, dvd player, etc)

refreshrate (in Hz) is from destination (monitor/tv/etc)

They are not interchangable unless they are equal.  (ie 30fps game will display 1frame per 2 cycles, while a 60fps game will display 1frame for every unique cycle, while a 120fps game will drop every other frame per cycle)


Ssenkahdavic: "They call it top/bottom (one is on top of the other) and together they equal 1920x1080p (it does not say anywhere it is per eye,"   Well, look at Figure 8-6 3D structure (Top-and-Bottom), it shows L on top, and Ron bottom! Am I, or are you, missing something? Which brings us back to my question, how can they call this a 1080p mode, when it's just 1920x540?

I'm totally aware of what 60hz means and 60fps means, your totally missing my point. I know what interlacing is, I know what FPS is, and I know what monitor refresh is. Your stating the obvious. If you do a timedemo in a game it removes the 60fps lock and runs the engine at full speed to give you the maximum average framerate that the engine can put out, and yes it looks like a speed up movie. This is all common knowledge. My point was this, most console games run at 30fps at 720p, if they can at all, and only a handfull have higher framerates/resolutions, SO, a tv that can only accept 1080p at up to 30hz is fine, most console games could not do that anyway!