AuthorTopic: Sub Pixels  (Read 5435 times)

Offline Grimsane

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Re: Sub Pixels

Reply #10 on: August 08, 2012, 05:25:32 pm
I'm not entirely sure, but I recall reading about and not sure if there is a matrix difference between VA (Vertical Alignment), TN (Twisted Nematic) and IPS (In Plane Switching)  LCD types, I have a vague recollection that TN monitors have horizontal sub pixels Vs Vertical.

might be wrong here but here's my assumption based on what I can recall



and I've read IPS stuff before and It's possible it doesn't even have sub pixels, actual mechanical/electronic/hardware colour blending per display pixel

so ontop of different RBG orders there is that factor too, so It further pushes the point manual adherence to 'real sub pixels' is fruitless, further adding to what I mentioned about theoretical software, it'll probably be a runtime based animation because it'd need to do the relevant sub pixel adjustments for different monitor types, as far as I know driver monitors actually effect the rendering of font too because of the sub pixel driven nature of it.

even so cons of using real sub pixels in animation is it will only work at 1x resolution, so you'd need graphics readable at 1x on most monitors, and as actual display pixels get smaller and smaller, it won't scale and will be impractical you won't even be able to perceive it unless your nose was against your display

Offline Mr. Fahrenheit

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Re: Sub Pixels

Reply #11 on: August 10, 2012, 12:11:12 pm
I was testing out a theory I had with sub pixels yesterday and it didnt work out as planned. I made a 36x36 pixel image and i filled it with the red green blue pattern for each block of three pixels.
I made what should be a white circle with slight antialiasing around a slightly purple background. However when i shrunk it to 1/3 of its size that is not what it was. is what I came up with, a green circle. I am not sure why this happened though i believe it is because the green subpixel is the subpixel most related to brightness.

Offline API-Beast

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Re: Sub Pixels

Reply #12 on: August 10, 2012, 12:30:55 pm
Scaling simply doesn't work like that  :-X It's green because you are scaling without interpolation so he simply picks every third pixel and discards everythng else. Unfortunally there are no graphics applications I know that have a additive or subpixel scaling mode, so you have to do it manually.

Offline Ashbad

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Re: Sub Pixels

Reply #13 on: August 10, 2012, 12:43:35 pm
I was testing out a theory I had with sub pixels yesterday and it didnt work out as planned. I made a 36x36 pixel image and i filled it with the red green blue pattern for each block of three pixels.
I made what should be a white circle with slight antialiasing around a slightly purple background. However when i shrunk it to 1/3 of its size that is not what it was. is what I came up with, a green circle. I am not sure why this happened though i believe it is because the green subpixel is the subpixel most related to brightness.

Well, for one, I tried it out in MSPaint to see if that's what you used -- I got the exact same result.  I honestly wouldn't trust MSP's abilities to conduct such an experiment.  In fact, I'm unsure of the point of said experiment, since the result of the scale-down and color blend would be entirely dependent on the algorithm of the used image editor for said procedure.  To further my point, try scaling down a 3x3 block with the first column red, second one green, third one blue.  Try scaling down the same thing except mirrored backwards.  Try rotating it 90 degrees and doing it.  Try rearranging the colors in other ways.  Every time will have a different result, and in fact, none of them will yield white.

As for the green subpixel being the "source of brightness", a simple look at what you've got there confirms that the green stands out from the other colors, almost as a white in contrast to the moderate red and very dark blue.  For a related tie-in: http://en.wikipedia.org/wiki/Luma_(video)#Rec._601_luma_versus_Rec._709_luma_coefficients

Offline Grimsane

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Re: Sub Pixels

Reply #14 on: August 10, 2012, 04:10:45 pm


bluring is the only reliable way to combine RGB values, rescaling linear cubic and sinc all produce images that try to maintain detail.

also if you open this in a new window and drag it around the screen you can identify sub pixel flicker ( i get quite alot at the very top portion of my screen)



also looking closely at something that will probably produce some strange effects, besides the subpixel wobble, on my screen it has a dark shapes flowing up and down and a wavy pattern in the colours, some of which could be an interesting effect happening due to vertical tearing (which presents it self as horizontal disturbances(doesn't work if Vsynch is on, and most systems can't Vsynch on desktop/outside of a fullscreen app)