How many individual pixels are there on the iPhone X screen?


MattXDA

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Aug 18, 2014
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Many people think that because the screen is higher resolution, the X will require more power to render objects on the display than the Plus models. However, this is not the case. The Plus models already render at the same 3x resolution as the X, yet then downsample this image for the 1080p display. This is an added step in the rendering process and means that the X will actually be more efficient than the Plus models in this aspect.

The iPhone X renders 2,740,500 pixels and the Plus models render 2,742,336, then downsample this

1*vysYQoG5R1dqDC_-d7JQAA.png
 

JPack

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Mar 27, 2017
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Thank you for this.

Myth #1: "iPhone X has more pixels to push than 8 Plus." False.

Myth #2: "iPhone X has a larger display area than the Plus series." False.

Myth #3: "iPhone 8 Plus has a larger battery capacity than the X." False.
 
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MacDevil7334

macrumors 65816
Oct 15, 2011
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You’re assuming it takes more battery power to computationally downsample the rendered pixels than it does driving the physical display. The two phones have to compute virtually the same number of pixel values (there are slightly more on the plus than on the X, but the difference is very small). The plus then has to mathematically downsample the image to 1920x1080 and then push that number of pixels on the screen. The X doesn’t have that middle downsampling step, instead driving the image at the native 1125x2436. I am definitely not an expert, but I’m guessing the power requirements for the downsampling step are dwarfed by the power needed to drive the 666,900 additional pixels on the physical display of the X since the downsampling is a mathematical computation and the A11 is quite power efficient. So, while both devices render roughly the same number of virtual pixels, the X has to push about 2/3rd of a million more physical pixels than the plus does. That’s definitely going to impact battery life, even if the X isn’t having to downsample the image first.
 
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DNichter

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Apr 27, 2015
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Philadelphia, PA
You’re assuming it takes more battery power to computationally downsample the rendered pixels than it does driving the physical display. The two phones have to compute virtually the same number of pixel values (there are slightly more on the plus than on the X, but the difference is very small). The plus then has to mathematically downsample the image to 1920x1080 and then push that number of pixels on the screen. The X doesn’t have that middle downsampling step, instead driving the image at the native 1125x2436. I am definitely not an expert, but I’m guessing the power requirements for the downsampling step are dwarfed by the power needed to drive the 666,900 additional pixels on the physical display of the X since the downsampling is a mathematical computation and the A11 is quite power efficient. So, while both devices render roughly the same number of virtual pixels, the X has to push about 2/3rd of a million more physical pixels than the plus does. That’s definitely going to impact battery life, even if the X isn’t having to downsample the image first.
Yea I would imagine. Apple laid this out as the X is 1 less hour in internet usage and video playback. Overall, I don't think it'll be an issue for anyone.
 

MattXDA

macrumors 6502
Aug 18, 2014
429
268
UK
You’re assuming it takes more battery power to computationally downsample the rendered pixels than it does driving the physical display. The two phones have to compute virtually the same number of pixel values (there are slightly more on the plus than on the X, but the difference is very small). The plus then has to mathematically downsample the image to 1920x1080 and then push that number of pixels on the screen. The X doesn’t have that middle downsampling step, instead driving the image at the native 1125x2436. I am definitely not an expert, but I’m guessing the power requirements for the downsampling step are dwarfed by the power needed to drive the 666,900 additional pixels on the physical display of the X since the downsampling is a mathematical computation and the A11 is quite power efficient. So, while both devices render roughly the same number of virtual pixels, the X has to push about 2/3rd of a million more physical pixels than the plus does. That’s definitely going to impact battery life, even if the X isn’t having to downsample the image first.
I meant CPU power :) People keep asking if the X will lag compared to the 8 Plus
 
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MattXDA

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Aug 18, 2014
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The Geekbench scores of the X are slightly lower than the 8 Plus, if that means anything.
Yeah I noticed that. I think the score will be higher when people try it for themselves though as it was most likely running beta software. If not, then it's still very high. None of the hardware specs would suggest it should be lower
 

Milese3

macrumors 6502
Aug 11, 2014
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Southampton - United Kingdom
Thank you for this.

Myth #1: "iPhone X has more pixels to push than 8 Plus." False.

Myth #2: "iPhone X has a larger display area than the Plus series." False.

Myth #3: "iPhone 8 Plus has a larger battery capacity than the X." False.
First point is interesting. Whilst the iP8 will render more pixels than the iPX, the iPX displays far more physical pixels. That and a (very very very slightly) larger battery is likely to make for a more vivid display without compromising on battery life. 1080p on the iP8+/.../6+ always seemed discontinuous to me.
 
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flat five

macrumors 603
Feb 6, 2007
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newyorkcity
Many people think that because the screen is higher resolution, the X will require more power to render objects on the display than the Plus models. However, this is not the case. The Plus models already render at the same 3x resolution as the X, yet then downsample this image for the 1080p display. This is an added step in the rendering process and means that the X will actually be more efficient than the Plus models in this aspect.

The iPhone X renders 2,740,500 pixels and the Plus models render 2,742,336, then downsample this

View attachment 725893
for the missing 'physical pixels' number on that chart..

the X looses about 2.4% of pixels due to the corners and notch.. say 65,750px
so its physical pixel count is somewhere around 2,675,000

no point really :)
just trying to fill in the blank where it says "the device screen may have lower pixel resolution than the image rendered in the previous step"