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Old 21st February 2015, 13:00   #40  |  Link
Arm3nian
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Join Date: Jul 2014
Location: Las Vegas
Posts: 177
Quote:
Originally Posted by Asmodian View Post
I have updated the chart.



I do not want to recommend particular resize methods or go into the subjective differences between them. The bar graphs in madVR already do a good job of that. The reason it might look messy on a mobile device is only because it uses bilinear, nearest neighbor, or similar which are also options in madVR.

Resizing methods are not codecs. Codec is short for "coder decoder" and usually referrers to software which codes images, video, or audio in a different format like JPEG, H.264, or MP3 and can then decode it back to the original format.



No. Imagine you start with an image at 3840x2160. You scale it down to 1920x1080. Now you want to upscale it so it looks as much like the original 3840x2160 image as it can. Nearest neighbor does not get very close. You want it to look as if it was the same content but at 2x the resolution, you do not want to represent the lower resolution source perfectly.

Also it is 2x the resolution, not 4x. 4x would be 8K or 7680x4320. A scaling factor of 1.414213562393095 is not a 2x upscale.

Image doubling generates 4 times the number of pixels. Image quadrupling generates 16 times the number of pixels.



I want to collect feedback on it for a bit before adding it to the end of the first post.
Yes, algorithm would be the correct term to use. However, your grammar lesson regarding resolution is incorrect. 4x the resolution of 1920x1080 is 3840x2160. Resolution implies the total number of the pixels. 7680x4320 is 4x horizontally and vertically, making it 8 times the resolution. It makes no sense to refer to resolution in only one dimension, there is 4x the amount of information, making it 4x the amount of resolution. Yes image doubling works in both directions, as Nev has stated to me in the past. Maybe madshi can explain why he calls it image doubling, I'm sure he has his reasons. Probably because to properly double an image, you would have to change the horizontal and vertical together, it would make no sense to say I doubled a 1920x1080 image to 3840x1080 even though the amount of pixels is 2x.

Anyway, a 1080p video looks quite good on my 1440p nexus 6, even though the renderer most likely uses crap interpolation. The 493ppi density hides artificats, not the same as a desktop monitor.
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