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Old 22nd February 2015, 01:44   #50  |  Link
Arm3nian
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Join Date: Jul 2014
Location: Las Vegas
Posts: 177
Quote:
Originally Posted by Asmodian View Post
Because we are talking about spacial resolution. If an image has 4x the information as another, it is 2x the resolution. This is based on the definition of resolution used by everyone except digital camera makers who want to be able to say they quadrupled the resolution when they really only doubled it.

Using your nomenclature 2x the resolution implies an irrational scaling factor of square root of 2 or only doubling one dimension. It sounds great for people trying to sell new models of digital cameras but no one else talks about resolution this way.

I am describing a standard so everyone uses the same words to mean the same thing. madshi obviously agrees given image doubling and as this thread is about madVR options let us stick to the terminology madVR uses. Everyone else who works with digital image processing thinks madshi got it right so this should not cause confusion. When you scale an image in Photoshop to "200%" you get 4 times the number of pixels.



No it isn't, that is 2x SSAA. 4x SSAA uses 16 times the pixels. 2x SSAA does not only filter the vertical or horizontal dimension and you cannot have square root of two pixel sampling.

I have not been able to find a statement from AMD or Nvidia but this is representative of what I was able to find:
Replace resolution with 'information'. If something has 4x the information of another thing, saying it has 2x instead makes no sense. If you want to say 2x the resolution, then you would have to independantly define and state that resolution x is 2 times greater horizontally and 2 times greater vertically than resolution y.

You are correct that we are talking about spacial resolution. If an image is 3840x2160, but its spacial resolution is lower, meaning the pixels are much more spread out, it might look the same as the same image at 1920x1080 at the correct distance. But, the 3840x2160 image still has more information, it just displayed incorrectly/differently.

Photoshop refers to 200% as 4x the pixels because it scales the horizontal and vertical together. Just like nnedi3. If it only scaled in one dimension, what would you call it? What is 3840x1080 compared to 1920x1080... using your defintion? You can't describe it. But you can say it is 2x the resolution, and 3840x2160 is 4x the resolution. It makes sense to refer to "scaling" as 2x, because you scale both directions together. But it does not make sense to refer to the entire resolution as 2x.

In triple A games, 4xSSAA is 4x the resolution. If 4xSSAA was 16x the pixels, it wouldn't exist in any games, you would need 4 gtx 980s running at 2200mhz cooled by ln2, obviously not realistic to implement.

Also, check the dynamic super resolution in your nvidia control panel. I am currently on a 1920x1200 monitor, and 4x the resolution is referred to as 3840x2400. Same multiplier scale is used for all the other dynamic super resolutions. 2x the resolution is 2715x1697.
Picture here: http://i.imgur.com/ID3XoBc.png

Quote:
Originally Posted by vivan View Post
So you should think not about resolution, but about directions. It's just that keeping separate settings for 2 directions doesn't make much sence, so they're combined.
Questionable. Nvidia inspector, as shown in my next post, allows you to configure the horizontal and vertical independantly of each other. This can provide better image quality without destroying your frame rate, as the picture rendered at the higher resolution is downsampled. Obviously this might not work properly in some games, or madvr for that matter, which is why it isn't an option in the applications itself, but rather the drivers. A 1920x1080 image scaled by 4x, is now 400% larger. Photoshop refers to it as 200% because Photoshop is an image editing tool. You can select to only the scale the horizontal or vertical by 200%, doesn't mean the amount of pixels increased fourfold. The 200% that results in 4x the pixels just means you increased the resolution by 2 in both directions.

Last edited by Arm3nian; 22nd February 2015 at 02:37.
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