RGB Color Model question
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I got a question that i've wanna know since a very long time. Why did we use the
RGB model on a computer screen or something like that if the 3 principal color
in the world are Red, YELLOW and blue??? Can somebody explain it to me?
Are eyes see red green and blue. Yellow is red and green combinded. You may be thinking of paint which works differently than light. The screen emits light so it uses RGB. I hope that made sence.
No. Our eyes have cones and rods inside. I cant remember which but one of them has three types. One red one green and one blue. The screen emits RGB because thats what we see. If the screen emited yellow we wouldnt be able to see green on it (yellow light + blue light != green light). Maybe you should look up how the eye and light works.
It might also help to think about the differences between paint and light. An object appear green to us because red and blue light are absorbed by the object while the green light is reflected. This is why as you mix paint colors together you get a darker result, less light is reflected and the paint tends towards black (or dark brown). With light however you get the opposite results. As you mix more lights together the color gets brighter, trending towards white.
The primary colors of pigment are actually cyan, yellow and magenta, and if you mix these together you (should) get black. Each of these is the same as a mixture of two primary colors of light: yellow = red + green, cyan = blue + green, magenta = red + blue. Yellow paint absorbes blue light, reflecting roughly equal ammounts of red and green. Cyan paint on the other hand absorbs red light, reflecting blue and green. If you mix these paints you'll get a color which absorbs both red and blue light, appearing green.
The primary colors of pigment are actually cyan, yellow and magenta, and if you mix these together you (should) get black. Each of these is the same as a mixture of two primary colors of light: yellow = red + green, cyan = blue + green, magenta = red + blue. Yellow paint absorbes blue light, reflecting roughly equal ammounts of red and green. Cyan paint on the other hand absorbs red light, reflecting blue and green. If you mix these paints you'll get a color which absorbs both red and blue light, appearing green.
We use a lot of different color models in everyday life. RGB is only one, and it's used because we can get crisp and consistent images on a computer monitor by using explicit values for the three photon emitters your monitor uses.
Television, on the other hand, is really black and white, with this really neat little "hack" to produce color. The common brightness channel ("Y") is just as it would be for black & white, but then two more channels ("Cr" and "Cb") are snuck into the packet stream, which color TV detects and adds to the image, and black & white TV just ignores because it doesn't know to look for these packets.
If you've got a GameCube, they use a cute trick to reduce memory usage. The final to-screen rendering buffer actually stores only one CrCb value pair for each two pixels, and stores one Y value for each and every pixel. Why? Because the human eye can't really tell, especially on a low-resolution and color-bled display like a TV. There's a photo compression technique which converts the image to YCrCb, and then stores only one Cr and Cb entry for each 4x4 block of pixels, simply because in a photo-like image you can't tell the difference.
Either on Google or Wikipedia, you should be able to find out lots about different color models.
Television, on the other hand, is really black and white, with this really neat little "hack" to produce color. The common brightness channel ("Y") is just as it would be for black & white, but then two more channels ("Cr" and "Cb") are snuck into the packet stream, which color TV detects and adds to the image, and black & white TV just ignores because it doesn't know to look for these packets.
If you've got a GameCube, they use a cute trick to reduce memory usage. The final to-screen rendering buffer actually stores only one CrCb value pair for each two pixels, and stores one Y value for each and every pixel. Why? Because the human eye can't really tell, especially on a low-resolution and color-bled display like a TV. There's a photo compression technique which converts the image to YCrCb, and then stores only one Cr and Cb entry for each 4x4 block of pixels, simply because in a photo-like image you can't tell the difference.
Either on Google or Wikipedia, you should be able to find out lots about different color models.
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